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Sleep-Opt-In: A Randomized Controlled Pilot Study to Improve Sleep and Glycemic Variability in Adults With Type 1 Diabetes.
Martyn-Nemeth, P, Duffecy, J, Quinn, L, Steffen, A, Baron, K, Chapagai, S, Burke, L, Reutrakul, S
The science of diabetes self-management and care. 2023;49(1):11-22
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Insufficient sleep (insufficient total sleep time) and irregular sleep timing (variability in the occurrence of sleep within a 24-hour period) are increasingly recognized as important contributors to glycaemic control and variability in type 1 diabetes (T1D). The aims of this study were to evaluate the feasibility and acceptability of a sleep intervention (Sleep-Opt-In) targeted for adults with type 1 diabetes with short or irregular sleep and to examine the effects of Sleep-Opt-In on sleep duration and regularity, glucose indices, and patient-reported outcomes. This study was a randomised controlled parallel trial design. Participants (n=14) were randomly assigned to either the Sleep-Opt-In intervention or a Healthy Living attention control group. Results showed that: - Sleep-Opt-In was feasible and acceptable to the target population. - participants with objectively confirmed short or irregular sleep, sleep irregularity improved by 25 minutes on average, whereas sleep duration improved only negligibly (8 minutes). - the control group experienced an increase in sleep duration but no change in sleep regularity. Authors conclude that Sleep-Opt-In is feasible, acceptable, and promising for further evaluation to improve sleep duration or regularity, glucose parameters and important patient reported outcomes of diabetes distress, daytime sleepiness, fatigue and depressive mood in the T1D population.
Abstract
PURPOSE The purpose of this study was to evaluate the feasibility and acceptability of a technology-assisted behavioral sleep intervention (Sleep-Opt-In) and to examine the effects of Sleep-Opt-In on sleep duration and regularity, glucose indices, and patient-reported outcomes. Short sleep duration and irregular sleep schedules are associated with reduced glycemic control and greater glycemic variability. METHODS A randomized controlled parallel-arm pilot study was employed. Adults with type 1 diabetes (n = 14) were recruited from the Midwest and randomized 3:2 to the sleep-optimization (Sleep-Opt-In) or Healthy Living attention control group. Sleep-Opt-In was an 8-week, remotely delivered intervention consisting of digital lessons, sleep tracker, and weekly coaching phone calls by a trained sleep coach. Assessments of sleep (actigraphy), glucose (A1C, continuous glucose monitoring), and patient-reported outcomes (questionnaires for daytime sleepiness, fatigue, diabetes distress, and depressive mood) were completed at baseline and at completion of the intervention. RESULTS Sleep-Opt-In was feasible and acceptable. Those in Sleep-Opt-In with objectively confirmed short or irregular sleep demonstrated an improvement in sleep regularity (25 minutes), reduced glycemic variability (3.2%), and improved time in range (6.9%) compared to the Healthy Living attention control group. Patient-reported outcomes improved only for the Sleep-Opt-In group. Fatigue and depressive mood improved compared to the control. CONCLUSIONS Sleep-Opt-In is feasible, acceptable, and promising for further evaluation as a means to improve sleep duration or regularity in the population of people with type 1 diabetes.
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Improving perinatal sleep via a scalable cognitive behavioural intervention: findings from a randomised controlled trial from pregnancy to 2 years postpartum.
Bei, B, Pinnington, DM, Quin, N, Shen, L, Blumfield, M, Wiley, JF, Drummond, SPA, Newman, LK, Manber, R
Psychological medicine. 2023;53(2):513-523
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Sleep disturbance is a universal experience during the pregnancy and postpartum periods. Sleep disturbance is linked to a range of negative consequences. Literature shows that cognitive behavioural Therapy for Insomnia (CBT-I) is an effective treatment, with comparable short-term and superior long-term effects to sleep medication alone. The aim of this study was to evaluate the short-, medium-, and long-term efficacy of a non-pharmacological sleep intervention in the perinatal periods. The study was a longitudinal randomised controlled trial based on the SEED (Sleep Eat Emotions and Development) project which was a two-arm, parallel-group, single-blind, superiority randomised controlled trial. Participants were pregnant women enrolled in Childbirth Education and were randomised 1:1 to the intervention or a comparison condition. Results showed that compared to receiving an attention- and time-matched control, receiving a cognitive behavioural sleep intervention was associated with lower symptoms of insomnia, sleep disturbance, and sleep-related impairment during late pregnancy. Moreover, the intervention had long-term benefits to gestational parents’ sleep at 2-year postpartum. Authors conclude that a scalable cognitive behavioural sleep intervention, tailored for the perinatal periods, is feasible, acceptable, and efficacious in buffering against the natural increase in sleep complaints during the 3rd trimester.
Abstract
BACKGROUND Sleep disturbance is common in gestational parents during pregnancy and postpartum periods. This study evaluated the feasibility and efficacy of a scalable cognitive behavioural therapy (CBT) sleep intervention tailored for these periods. METHODS This is a two-arm, parallel-group, single-blind, superiority randomised controlled trial. Nulliparous females without severe medical/psychiatric conditions were randomised 1:1 to CBT or attention- and time-matched control. All participants received a 1 h telephone session and automated multimedia emails from the third trimester until 6 months postpartum. Outcomes were assessed with validated instruments at gestation weeks 30 (baseline) and 35 (pregnancy endpoint), and postpartum months 1.5, 3, 6 (postpartum endpoint), 12 and 24. RESULTS In total, 163 eligible participants (age M ± s.d. = 33.35 ± 3.42) were randomised. The CBT intervention was well accepted, with no reported adverse effect. Intention-to-treat analyses showed that compared to control, receiving CBT was associated with lower insomnia severity and sleep disturbance (two primary outcomes), and lower sleep-related impairment at the pregnancy endpoint (p values ⩽ 0.001), as well as at 24 months postpartum (p ranges 0.012-0.052). Group differences across the first postpartum year were non-significant. Participants with elevated insomnia symptoms at baseline benefitted substantially more from CBT (v. control), including having significantly lower insomnia symptoms throughout the first postpartum year. Group differences in symptoms of depression or anxiety were non-significant. CONCLUSIONS A scalable CBT sleep intervention is efficacious in buffering against sleep disturbance during pregnancy and benefitted sleep at 2-year postpartum, especially for individuals with insomnia symptoms during pregnancy. The intervention holds promise for implementation into routine perinatal care.
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An Energy-Reduced Mediterranean Diet, Physical Activity, and Body Composition: An Interim Subgroup Analysis of the PREDIMED-Plus Randomized Clinical Trial.
Konieczna, J, Ruiz-Canela, M, Galmes-Panades, AM, Abete, I, Babio, N, Fiol, M, Martín-Sánchez, V, Estruch, R, Vidal, J, Buil-Cosiales, P, et al
JAMA network open. 2023;6(10):e2337994
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The Mediterranean diet (MedDiet), which focuses on whole grains, lean meat, fruits, vegetables, and low amounts of minimally processed foods has been shown in previous research to improve body composition and decrease fat storage around the middle. This randomised control trial of 1556 older adults aimed to determine the effects of combining a 30% lower energy version of the MedDiet in combination with physical exercise on body composition. After 3 years, the results showed that compared to a normal MedDiet without exercise, the lower energy version in combination with exercise improved body composition by decreasing total fat, and the fat stored around the organs and increasing muscle mass. However, benefits were more pronounced after 1 year and decreased slightly at 3 years. It was concluded that a low energy MedDiet in combination with physical activity may be able to improve the body composition of overweight and older adults with obesity. This study could be used by healthcare professionals to recommend a low energy MedDiet to older adults to promote weight loss, whilst attenuating muscle loss associated with ageing.
Expert Review
Conflicts of interest:
None
Take Home Message:
- The addition of exercise to an energy-reduced diet, which focuses on whole grains, healthy fats, lean protein, and fruits and vegetables can emphasise positive effects on body composition in older adults.
- However, there is a loss of lean mass associated with this type of diet (contrary to author conclusions) and measures should be taken to monitor and increase protein intake to prevent or limit this loss.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
This study aimed to determine the long-term effects of an energy reduced MedDiet in combination with physical activity on body composition.
Methods
- This is a predetermined 3-year interim analysis of a 6-year single-blind, randomised control trial of 1556 individuals aged 55-75 who are overweight or obese with metabolic syndrome.
- 760 individuals on 30% energy reduced MedDiet with limited processed foods, plus 45 minutes walking 6 days per week and behavioural and motivational support. [Intervention group]
- 761 on standard MedDiet without physical activity. [Control]
Results
Within group comparisons showed that individuals in the intervention group lost (P value represents baseline vs year 3):
- Total fat mass percentage (1-year vs baseline, −1.14%; 95% CI, −1.32% to −0.96%; 3-year vs baseline, −0.52%; 95% CI, −0.71% to −0.33% P=<0.001)
- Absolute visceral fat (1-year vs baseline, −154 g; 95% CI, −191 to −116 g; 3-year vs baseline, −75.1 g, 95% CI, −115 to −35.3 g P=<0.001)
- Absolute total fat after 1 year (mean change at 1 year vs baseline, −1677 g; 95% CI, −1930 to −1424 g) but regained some at year 3 (mean change at 3 years vs baseline, −1018 g; 95% CI, −1280 to −756 g P=<0.001)
- Absolute lean mass (mean change at 1 year vs baseline −300 g; 95% CI, −439 to −162 g) with further losses at year 3 (−626 g; 95% CI, −770 to −483 g P=0.001).
Within group comparisons also showed significantly increased:
- Total lean mass percentage, which was greater at year 1 than year 3 (1-year vs baseline, 1.07%; 95%CI, 0.90%-1.25%; 3-year vs baseline, 0.47%; 95% CI, 0.29%-0.65% P=<0.001).
As a result of total fat loss and some lean mass in the intervention group, the lean:fat mass ratio improved and was unchanged in the control group (between group differences (P=<0.001).
Compared to women, men may find the MedDiet + exercise more beneficial as it was shown that body composition changes were slightly more pronounced in men.
Conclusion
An energy-reduced MedDiet plus exercise emphasised positive changes to body composition compared to standard MedDiet in older adults who are overweight or have obesity.
Clinical practice applications:
- The recommendation of a reduced energy MedDiet in combination with physical activity to older people who are overweight or obese may improve body composition.
- Although lean mass loss slowed between years 1 and 3, other practices should be employed to attenuate the loss of lean mass associated with an energy-reduced MedDiet and ageing.
Considerations for future research:
- The research has not yet concluded but when it does, it will address the incidence of cardiovascular disease along with body composition changes.
- It will also look at long-term effects of the diet to determine longevity.
- Future research could focus on how to limit lean mass loss through the possibility of changing the type of exercise that accompanies the MedDiet.
Abstract
IMPORTANCE Strategies targeting body composition may help prevent chronic diseases in persons with excess weight, but randomized clinical trials evaluating lifestyle interventions have rarely reported effects on directly quantified body composition. OBJECTIVE To evaluate the effects of a lifestyle weight-loss intervention on changes in overall and regional body composition. DESIGN, SETTING, AND PARTICIPANTS The ongoing Prevención con Dieta Mediterránea-Plus (PREDIMED-Plus) randomized clinical trial is designed to test the effect of the intervention on cardiovascular disease prevention after 8 years of follow-up. The trial is being conducted in 23 Spanish research centers and includes men and women (age 55-75 years) with body mass index between 27 and 40 and metabolic syndrome. The trial reported herein is an interim subgroup analysis of the intermediate outcome body composition after 3-year follow-up, and data analysis was conducted from February 1 to November 30, 2022. Of 6874 total PREDIMED-Plus participants, a subsample of 1521 individuals, coming from centers with access to a dual energy x-ray absorptiometry device, underwent body composition measurements at 3 time points. INTERVENTION Participants were randomly allocated to a multifactorial intervention based on an energy-reduced Mediterranean diet (MedDiet) and increased physical activity (PA) or to a control group based on usual care, with advice to follow an ad libitum MedDiet, but no physical activity promotion. MAIN OUTCOMES AND MEASURES The outcomes (continuous) were 3-year changes in total fat and lean mass (expressed as percentages of body mass) and visceral fat (in grams), tested using multivariable linear mixed-effects models. Clinical relevance of changes in body components (dichotomous) was assessed based on 5% or more improvements in baseline values, using logistic regression. Main analyses were performed in the evaluable population (completers only) and in sensitivity analyses, multiple imputation was performed to include data of participants lost to follow-up (intention-to-treat analyses). RESULTS A total of 1521 individuals were included (mean [SD] age, 65.3 [5.0] years; 52.1% men). In comparison with the control group (n=761), participants in the intervention arm (n=760) showed greater reductions in the percentage of total fat (between group differences after 1-year, -0.94% [95% CI, -1.19 to -0.69]; 3 years, -0.38% [95% CI, -0.64 to -0.12] and visceral fat storage after 1 year, -126 g [95% CI, -179 to -73.3 g]; 3 years, -70.4 g [95% CI, -126 to -15.2 g] and greater increases in the percentage of total lean mass at 1 year, 0.88% [95% CI, 0.63%-1.12%]; 3-years 0.34% [95% CI, 0.09%-0.60%]). The intervention group was more likely to show improvements of 5% or more in baseline body components (absolute risk reduction after 1 year, 13% for total fat mass, 11% for total lean mass, and 14% for visceral fat mass; after 3-years: 6% for total fat mass, 6% for total lean mass, and 8% for visceral fat mass). The number of participants needed to treat was between 12 and 17 to attain at least 1 individual with possibly clinically meaningful improvements in body composition. CONCLUSIONS AND RELEVANCE The findings of this trial suggest a weight-loss lifestyle intervention based on an energy-reduced MedDiet and physical activity significantly reduced total and visceral fat and attenuated age-related losses of lean mass in older adults with overweight or obesity and metabolic syndrome. Continued follow-up is warranted to confirm the long-term consequences of these changes on cardiovascular clinical end points. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN89898870.
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Docosahexaenoic acid (DHA) intake estimated from a 7-question survey identifies pregnancies most likely to benefit from high-dose DHA supplementation.
Christifano, DN, Crawford, SA, Lee, G, Brown, AR, Camargo, JT, Kerling, EH, Gajewski, BJ, Valentine, CJ, Gustafson, KM, DeFranco, EA, et al
Clinical nutrition ESPEN. 2023;53:93-99
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Preterm birth (PTB) is the primary cause of infant mortality worldwide; and infants who survive have a higher risk of child disability. A recent Cochrane Review concluded that there is strong evidence that omega-3 fatty acids, especially docosahexaenoic acid (DHA), reduce early PTB (EPTB, <34 weeks gestation) and PTB (<37 weeks gestation) by 42% and 11%, respectively. The aim of this study was to investigate whether DHA intake at baseline alone could identify pregnancies for which high dose DHA supplementation lowered risk of EPTB and PTB. This study used the results from two randomised clinical trials of DHA supplementation during pregnancy in which participants completed the DHA-Food Frequency Questionnaire (FFQ) before randomisation to 200mg/day or high dose DHA, i.e., 800mg/day or 1000mg/day. A total of 1400 participants were enrolled in the two trials. Results show that the DHA-FFQ predicted participants whose risk of EPTB and PTB was reduced by consuming a DHA supplement of 800mg/day or 1000mg/day compared to 200mg/day. In fact, participants who started the study with an average daily DHA intake of <150mg had a 64% lower rate of EPTB and a 24% lower rate of PTB if they were assigned to 800mg/day or 1000mg/day compared to 200mg/day DHA. Authors conclude that the DHA-FFQ identifies women who could benefit from high dose DHA supplementation at least as effectively as a blood measure of DHA but with far fewer barriers for clinical implementation.
Abstract
BACKGROUND Two randomized trials found women with low blood docosahexaenoic acid (DHA; an omega 3 fatty acid) had fewer early preterm births (<34 weeks gestation) if they were assigned to high dose DHA supplementation, however, there is currently no capacity for clinicians who care for pregnancies to obtain a blood assessment of DHA. Determining a way to identify women with low DHA intake whose risk could be lowered by high dose DHA supplementation is desired. OBJECTIVE To determine if assessing DHA intake can identify pregnancies that benefit from high dose DHA supplementation. STUDY DESIGN This secondary analysis used birth data from 1310 pregnant women who completed a 7-question food frequency questionnaire (DHA-FFQ) at 16.8 ± 2.5 weeks gestation that is validated to assess DHA status. They were then randomly assigned to a standard (200 mg/day) or high dose (800 or 1000 mg/day) DHA supplement for the remainder of pregnancy. Bayesian logistic regressions were fitted for early preterm birth and preterm birth as a function of DHA intake and assigned DHA dose. RESULTS Participants who consumed less than 150 mg/day DHA prior to 20 weeks' gestation (n = 810/1310, 58.1%) had a lower Bayesian posterior probability (pp) of early preterm birth if they were assigned to high dose DHA supplementation (1.4% vs 3.9%, pp = 0.99). The effect on preterm birth (<37 weeks) was also significant (11.3% vs 14.8%, pp = 0.97). CONCLUSION The DHA-FFQ can identify pregnancies that will benefit most from high dose DHA supplementation and reduce the risk of preterm birth. The DHA-FFQ is low burden to providers and patients and could be easily implemented in obstetrical practice.
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Associations between plant-based dietary patterns and risks of type 2 diabetes, cardiovascular disease, cancer, and mortality - a systematic review and meta-analysis.
Wang, Y, Liu, B, Han, H, Hu, Y, Zhu, L, Rimm, EB, Hu, FB, Sun, Q
Nutrition journal. 2023;22(1):46
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According to the World Health Organization, type 2 diabetes (T2D), cardiovascular disease (CVD), and cancer account for nearly one in every two deaths globally. These diseases have significant clinical and public health implications. This study's aim was to assess the association of adherence to plant-based dietary patterns and changes in them with risks of major chronic diseases, including T2D, CVD, and cancer, and mortality. This study was a systematic review and meta-analysis of 55 prospective studies. Results showed that greater adherence to a plant-based dietary pattern was inversely associated with risks of T2D, CVD, cancer and all-cause mortality. Associations for T2D, CVD, and cancer were strengthened when the plant-based diets further emphasised healthful plant-based foods, such as vegetables, fruits, whole grains, and legumes. Authors concluded that their findings support the current recommendations that emphasise consuming high-quality plant-based foods for achieving optimal health.
Abstract
BACKGROUND Plant-based dietary patterns are gaining more attention due to their potential in reducing the risk of developing major chronic diseases, including type 2 diabetes (T2D), cardiovascular disease (CVD), cancer, and mortality, while an up-to-date comprehensive quantitative review is lacking. This study aimed to summarize the existing prospective observational evidence on associations between adherence to plant-based dietary patterns and chronic disease outcomes. METHODS We conducted a systematic review and meta-analysis of evidence across prospective observational studies. The data sources used were PubMed and MEDLINE, Embase, Web of Science, and screening of references. We included all prospective observational studies that evaluated the association between adherence to plant-based dietary patterns and incidence of T2D, CVD, cancer, and mortality among adults (≥ 18 years). RESULTS A total of 76 publications were identified, including 2,230,443 participants with 60,718 cases of incident T2D, 157,335 CVD cases, 57,759 cancer cases, and 174,435 deaths. An inverse association was observed between higher adherence to a plant-based dietary pattern and risks of T2D (RR, 0.82 [95% CI: 0.77-0.86]), CVD (0.90 [0.85-0.94]), cancer (0.91 [0.87-0.96]), and all-cause mortality (0.84 [0.78-0.92]) with moderate to high heterogeneity across studies (I2 ranged: 47.8-95.4%). The inverse associations with T2D, CVD and cancer were strengthened when healthy plant-based foods, such as vegetables, fruits, whole grains, and legumes, were emphasized in the definition of plant-based dietary patterns (T2D: 0.79 [0.72-0.87]; CVD: 0.85 [0.80-0.92]; cancer: 0.86 [0.80-0.92]; I2 ranged: 53.1-84.1%). Association for mortality was largely similar when the analyses were restricted to healthy plant-based diets (0.86 [0.80-0.92], I2 = 91.9%). In contrast, unhealthy plant-based diets were positively associated with these disease outcomes. Among four studies that examined changes in dietary patterns, increased adherence to plant-based dietary patterns was associated with a significantly reduced risk of T2D (0.83 [0.71-0.96]; I2 = 71.5%) and a marginally lower risk of mortality (0.95 [0.91-1.00]; I2 = 0%). CONCLUSIONS Better adherence to plant-based dietary patterns, especially those emphasizing healthy plant-based foods, is beneficial for lowering the risks of major chronic conditions, including T2D, CVD, cancer, as well as premature deaths. REGISTRATION OF REVIEW PROTOCOL This review was registered at the PROSPERO International Prospective Register of Systematic Reviews ( https://www.crd.york.ac.uk/PROSPERO/ ) with the registration number CRD42022290202.
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Effects of a low-carbohydrate diet on insulin-resistant dyslipoproteinemia-a randomized controlled feeding trial.
Ebbeling, CB, Knapp, A, Johnson, A, Wong, JMW, Greco, KF, Ma, C, Mora, S, Ludwig, DS
The American journal of clinical nutrition. 2022;115(1):154-162
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Diets high in carbohydrates and particularly processed carbohydrates can increase the risk for developing a dysfunction in the body’s ability to take up sugar from the blood, known as insulin resistance. However how this relates to insulin resistance can contribute to the development of many diseases such as type 2 diabetes, heart disease and stroke, which highlights the importance in preventing this dysfunction. This randomised control trial of 148 individuals aimed to determine the role of low, medium, and high carbohydrate diets with varying saturated fat content on measures for insulin resistance. The results showed that regardless of the fat content, it was the level of carbohydrate that determined the effect on measures of insulin resistance. High saturated fat and low-carbohydrate diets improved insulin resistance and low saturated fat high carbohydrate diets worsened insulin resistance. Improvements were also observed in blood lipids with a high fat low carbohydrate diet. It was concluded that a diet low in carbohydrates, but high in saturated fat improved insulin resistance and blood lipid levels. This study could be used by healthcare professionals to understand that a diet, which replaces fat with carbohydrates may be worsening insulin resistance and that low carbohydrate diets may be of benefit.
Abstract
BACKGROUND Carbohydrate restriction shows promise for diabetes, but concerns regarding high saturated fat content of low-carbohydrate diets limit widespread adoption. OBJECTIVES This preplanned ancillary study aimed to determine how diets varying widely in carbohydrate and saturated fat affect cardiovascular disease (CVD) risk factors during weight-loss maintenance. METHODS After 10-14% weight loss on a run-in diet, 164 participants (70% female; BMI = 32.4 ± 4.8 kg/m2) were randomly assigned to 3 weight-loss maintenance diets for 20 wk. The prepared diets contained 20% protein and differed 3-fold in carbohydrate (Carb) and saturated fat as a proportion of energy (Low-Carb: 20% carbohydrate, 21% saturated fat; Moderate-Carb: 40%, 14%; High-Carb: 60%, 7%). Fasting plasma samples were collected prerandomization and at 20 wk. Lipoprotein insulin resistance (LPIR) score was calculated from triglyceride-rich, high-density, and low-density lipoprotein particle (TRL-P, HDL-P, LDL-P) sizes and subfraction concentrations (large/very large TRL-P, large HDL-P, small LDL-P). Other outcomes included lipoprotein(a), triglycerides, HDL cholesterol, LDL cholesterol, adiponectin, and inflammatory markers. Repeated measures ANOVA was used for intention-to-treat analysis. RESULTS Retention was 90%. Mean change in LPIR (scale 0-100) differed by diet in a dose-dependent fashion: Low-Carb (-5.3; 95% CI: -9.2, -1.5), Moderate-Carb (-0.02; 95% CI: -4.1, 4.1), High-Carb (3.6; 95% CI: -0.6, 7.7), P = 0.009. Low-Carb also favorably affected lipoprotein(a) [-14.7% (95% CI: -19.5, -9.5), -2.1 (95% CI: -8.2, 4.3), and 0.2 (95% CI: -6.0, 6.8), respectively; P = 0.0005], triglycerides, HDL cholesterol, large/very large TRL-P, large HDL-P, and adiponectin. LDL cholesterol, LDL-P, and inflammatory markers did not differ by diet. CONCLUSIONS A low-carbohydrate diet, high in saturated fat, improved insulin-resistant dyslipoproteinemia and lipoprotein(a), without adverse effect on LDL cholesterol. Carbohydrate restriction might lower CVD risk independently of body weight, a possibility that warrants study in major multicentered trials powered on hard outcomes. The registry is available through ClinicialTrials.gov: https://clinicaltrials.gov/ct2/show/NCT02068885.
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Oxidative Stress and Inflammation Are Associated With Age-Related Endothelial Dysfunction in Men With Low Testosterone.
Babcock, MC, DuBose, LE, Witten, TL, Stauffer, BL, Hildreth, KL, Schwartz, RS, Kohrt, WM, Moreau, KL
The Journal of clinical endocrinology and metabolism. 2022;107(2):e500-e514
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Serum testosterone declines gradually with age at a rate of ~1% per year after the third decade. Vascular aging, featuring endothelial dysfunction mediated by oxidative stress and inflammation, is a major risk factor for the development of age-associated cardiovascular disease (CVD). The aim of this study was to examine the effects of low testosterone on cardiovascular aging in men. This study is a cross-sectional study which recruited 58 healthy men of all races/ethnic backgrounds aged 50-75 years (middle-aged/older) and 18-40 years (young). Results show that middle-aged/older men with lower testosterone have evidence of “accelerated” vascular aging, as indicated by a greater age-associated endothelial dysfunction of large arteries compared with their age-matched peers. The greater macrovascular endothelial dysfunction in middle-aged/older men with chronically low testosterone was independent of CVD risk factors or symptoms of androgen deficiency. Furthermore, increased systemic oxidative stress and inflammation are mechanistically linked to the greater age-associated endothelial dysfunction in middle-aged/older men with lower testosterone. Authors conclude that normal physiological levels of testosterone may be beneficial to cardiovascular health by attenuating the age-related decline in endothelial function.
Abstract
CONTEXT Vascular aging, including endothelial dysfunction secondary to oxidative stress and inflammation, increases the risk for age-associated cardiovascular disease (CVD). Low testosterone in middle-aged/older men is associated with increased CVD risk. OBJECTIVE We hypothesized that low testosterone contributes to age-associated endothelial dysfunction, related in part to greater oxidative stress and inflammation. METHODS This cross-sectional study included 58 healthy, nonsmoking men categorized as young (N = 20; age 29 ± 4 years; testosterone 500 ± 58 ng/dL), middle-aged/older with higher testosterone (N = 20; age 60 ± 6 years; testosterone 512 ± 115 ng/dL), and middle-aged/older lower testosterone (N = 18; age 59 ± 8 years; testosterone 269 ± 48 ng/dL). Brachial artery flow-mediated dilation (FMDBA) was measured during acute infusion of saline (control) and vitamin C (antioxidant). Markers of oxidative stress (total antioxidant status and oxidized low-density lipoprotein cholesterol), inflammation (interleukin [IL]-6 and C-reactive protein [CRP]), and androgen deficiency symptoms were also examined. RESULTS During saline, FMDBA was reduced in middle-aged/older compared with young, regardless of testosterone status (P < 0.001). FMDBA was reduced in middle-aged/older lower testosterone (3.7% ± 2.0%) compared with middle-aged/older higher testosterone (5.7% ± 2.2%; P = 0.021), independent of symptoms. Vitamin C increased FMDBA (to 5.3% ± 1.6%; P = 0.022) in middle-aged/older lower testosterone but had no effect in young (P = 0.992) or middle-aged/older higher testosterone (P = 0.250). FMDBA correlated with serum testosterone (r = 0.45; P < 0.001), IL-6 (r = -0.41; P = 0.002), and CRP (r = -0.28; P = 0.041). CONCLUSION Healthy middle-aged/older men with low testosterone appear to have greater age-associated endothelial dysfunction, related in part to greater oxidative stress and inflammation. These data suggest that low testosterone concentrations may contribute to accelerated vascular aging in men.
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Circulating levels of maternal vitamin D and risk of ADHD in offspring: results from the Vitamin D Antenatal Asthma Reduction Trial.
Chu, SH, Huang, M, Kelly, RS, Kachroo, P, Litonjua, AA, Weiss, ST, Lasky-Su, J
International journal of epidemiology. 2022;51(3):910-918
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Acting as both a nutrient and a hormone, vitamin D has been found to play a critical role in neurodevelopment across sensitive periods in utero, infancy and early childhood. Among neurodevelopmental and behavioural disorders in early life, attention-deficit/hyperactivity disorder (ADHD) is the most common among children worldwide. Low levels of circulating 25-hydroxy-vitamin D [25(OH)D] have been shown to associate with prevalent ADHD. The aims of this study were to (i) determine the association between maternal vitamin D levels in the first and third trimesters of pregnancy and the risk of offspring ADHD by age 6 years or later; and (ii) to identify potential sensitive periods in utero during which vitamin D levels might be most important for reducing risk of ADHD. This is an ancillary study of the Vitamin D Antenatal Asthma Reduction Trial (VDAART). The VDAART was a randomised, double-blinded, multicentre, clinical trial in which 876 participating mothers were recruited between 10–18 weeks of gestation and assigned to receive either 4400 or 400 IU/day of vitamin D throughout pregnancy. Results show protective associations between maternal 25(OH)D sufficiency in the third trimester and child ADHD, but not at baseline. Furthermore, both at baseline and in the third trimester, there were higher odds of ADHD in male offspring as compared with female offspring with 25(OH)D insufficient mothers (analyses limited by small sample sizes) Authors conclude that higher levels of maternal vitamin D during pregnancy may play a protective role against risk of ADHD in offspring, but further studies are needed to confirm this association and any therapeutic potential therein.
Expert Review
Conflicts of interest:
None
Take Home Message:
Ensure that women in pregnancy, and possibly also those seeking to conceive, have adequate vitamin D status in order to reduce the risk of ADHD in offspring.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Background
This paper describes a secondary data analysis from an RCT that looked at the effect of prenatal vitamin D supplementation on risk of childhood asthma in offspring. Enrolled women aged 18–39 years with a history of asthma, eczema or allergic rhinitis, or whose partner (biological father of child) had a history of the aforementioned condition, received either 400 IU or 4400 IU vitamin D daily for the duration of their pregnancy. Offspring follow-up is still ongoing.
Aims
The current study aims were twofold: (i) to determine the association between maternal vitamin D levels in trimesters 1 and 3 and the risk of attention deficit/hyperactivity disorder (ADHD) in offspring diagnosed by age 6 years or later; and (ii) to identify potentially sensitive periods during gestation in which vitamin D levels may be especially important for reducing risk of ADHD.
Methods
The analytical sample included 679 mother-child pairs, from the original sample of 876 participating mothers. No sample size calculation was reported, though the sample was considered representative of the overall RCT study population.
Maternal vitamin D (serum 25(OH)D) was classified as follows
- Highly deficient <12 ng/mL
- Deficient 12 ng/mL to 19.9 ng/mL
- Insufficient 20 ng/mL to 29.9 ng/mL
- Sufficient ≥30 ng/mL
ADHD status was assessed through parental reporting between ages 6 and 9 years.
Results
No baseline associations between a vitamin D sufficient status and offspring ADHD in maternal samples collected during trimester 1 were observed (OR 1.06, 95% CI 0.51–2.19; P.0.871), though this association became statistically significant at trimester 3 (OR 0.47, 95% CI 0.26–0.84; P.0.011). This translated to a 53% less chance of having a child with ADHD at age 6 or later among mothers with vitamin D sufficiency compared with children of mothers with vitamin D deficiency. There was also a linear trend in the protective association of vitamin D sufficiency (≥30 ng/mL) on reduced risk of offspring ADHD at age 6 years or later in data from trimester 3. Stratified analyses revealed a protective association for sufficient maternal vitamin D status and offspring ADHD among males (OR 0.47, 95% CI 0.23–0.94).
Conclusions
The authors concluded that vitamin D sufficiency (≥30 ng/mL) in the 3rd trimester of gestation may decrease the risk of ADHD development in offspring.
Notes: The authors reported no relevant conflicts of interest.
Clinical practice applications:
Ensuring a sufficient vitamin D status by the 3rd trimester of pregnancy may help to lessen the risk of ADHD in offspring. Nutritional therapists and other clinicians working with pregnant women or women looking to conceive should consider checking vitamin D status and providing corrective supplementation and lifestyle advice to augment vitamin D levels where indicated.
Considerations for future research:
The authors of this study postulated that the statistically significant protective association between vitamin D at trimester 3 and ADHD in offspring was not significant in trimester 1 due to a low observed variability in vitamin D status (>75% of women were vitamin D insufficient), and thus the statistical test being underpowered to see difference between groups with sufficient or insufficient status.
Further research could expand upon this hypothesis to test whether vitamin D status in trimester 1, or preconceptually, may offer a protective association for ADHD and other related neurological conditions that may manifest in early life.
Abstract
BACKGROUND Low levels of circulating 25-hydroxy-vitamin D [25(OH)D] have been shown to associate with prevalent attention-deficit/hyperactivity disorder (ADHD), but few studies have examined the association between 25(OH)D during fetal development and risk of childhood ADHD. METHODS Maternal plasma 25(OH)D was measured at 10-18 and 32-38 weeks of gestation, with sufficiency defined as 25(OH)D ≥ 30 ng/ml. Offspring ADHD status between ages 6-9 years was measured by parent report of clinical ADHD diagnosis among 680 mother-child pairs from the Vitamin D Antenatal Asthma Reduction Trial. Association between maternal 25(OH)D and child ADHD was assessed using logistic regression, adjusting for maternal age, race and ethnicity. Effect modification by offspring sex was also assessed. RESULTS No associations between maternal 25(OH)D at 10-18 weeks of gestation and offspring ADHD were observed. In the third trimester, we observed associations between maternal vitamin D sufficiency and offspring ADHD [odds ratio (OR) 0.47, 95% confidence interval (CI) 0.26-0.84], in addition to maternal 25(OH)D sufficiency category, comparing the deficient (OR 0.34, 95% CI 0.12-0.94), insufficient (OR 0.41, 95% CI 0.15-1.10) and sufficient (OR 0.20, 95% CI 0.08-0.54) categories against highly deficient 25(OH)D, respectively. Stratified analyses revealed a protective association for sufficient maternal 25(OH)D and child ADHD among males (OR 0.47, 95% CI 0.23-0.94); the synergy index for additive effect modification of risk was 1.78 (95% CI 0.62-5.08). CONCLUSIONS Higher levels of maternal vitamin D in the third trimester are associated with lower risk of ADHD in offspring, with modest evidence for a stronger effect among male offspring. However, larger studies will be necessary to confirm these findings.
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9.
Cardiometabolic Risk Factors and Incident Cardiovascular Disease Events in Women vs Men With Type 1 Diabetes.
Braffett, BH, Bebu, I, El Ghormli, L, Cowie, CC, Sivitz, WI, Pop-Busui, R, Larkin, ME, Gubitosi-Klug, RA, Nathan, DM, Lachin, JM, et al
JAMA network open. 2022;5(9):e2230710
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In the general population, women have a lower absolute risk of cardiovascular disease (CVD) compared with men. However, among individuals with type 1 or type 2 diabetes, the relative risk of CVD is similar or higher in women compared with men. The aim of this study was to assess sex differences in achieving recommended CVD risk management targets and associations with CVD events. This is a cohort study which included a total of 1441 (men n= 736) participants with type 1 diabetes. Results show that the prevalence and mean levels of most cardiometabolic risk factors (except for pulse rate and haemoglobin A1c) were consistent with a less atherogenic profile among women compared with men. Furthermore, achieving treatment targets for blood pressure, lipids, and glucose was associated with significantly decreased risk of CVD in both women and men. Authors conclude that their findings argue for a recalibration of CVD risk factor stratification in revised clinical care guidelines and therapeutic recommendations by sex for individuals with type 1 diabetes.
Abstract
IMPORTANCE The lower risk of cardiovascular disease (CVD) among women compared with men in the general population may be diminished among those with diabetes. OBJECTIVE To evaluate cardiometabolic risk factors and their management in association with CVD events in women vs men with type 1 diabetes enrolled in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study. DESIGN, SETTING, AND PARTICIPANTS This cohort study used data obtained during the combined DCCT (randomized clinical trial, conducted 1983-1993) and EDIC (observational study, conducted 1994 to present) studies through April 30, 2018 (mean [SD] follow-up, 28.8 [5.8] years), at 27 clinical centers in the US and Canada. Data analyses were performed between July 2021 and April 2022. EXPOSURE During the DCCT phase, patients were randomized to intensive vs conventional diabetes therapy. MAIN OUTCOMES AND MEASURES Cardiometabolic risk factors and CVD events were assessed via detailed medical history and focused physical examinations. Blood and urine samples were assayed centrally. CVD events were adjudicated by a review committee. Linear mixed models and Cox proportional hazards models evaluated sex differences in cardiometabolic risk factors and CVD risk over follow-up. RESULTS A total of 1441 participants with type 1 diabetes (mean [SD] age at DCCT baseline, 26.8 [7.1] years; 761 [52.8%] men; 1390 [96.5%] non-Hispanic White) were included. Over the duration of the study, compared with men, women had significantly lower body mass index (BMI, calculated as weight in kilograms divided by height in meters squared; β = -0.43 [SE, 0.16]; P = .006), waist circumference (β = -10.56 cm [SE, 0.52 cm]; P < .001), blood pressure (systolic: β = -5.77 mm Hg [SE, 0.35 mm Hg]; P < .001; diastolic: β = -3.23 mm Hg [SE, 0.26 mm Hg]; P < .001), and triglyceride levels (β = -10.10 mg/dL [SE, 1.98 mg/dL]; P < .001); higher HDL cholesterol levels (β = 9.36 mg/dL [SE, 0.57 mg/dL]; P < .001); and similar LDL cholesterol levels (β = -0.76 mg/dL [SE, 1.22 mg/dL]; P = .53). Women, compared with men, achieved recommended targets more frequently for blood pressure (ie, <130/80 mm Hg: 90.0% vs 77.4%; P < .001) and triglycerides (ie, <150 mg/dL: 97.3% vs 90.5%; P < .001). However, sex-specific HDL cholesterol targets (ie, ≥50 mg/dL for women, ≥40 mg/dL for men) were achieved less often (74.3% vs 86.6%; P < .001) and cardioprotective medications were used less frequently in women than men (ie, angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker: 29.6% [95% CI, 25.7%-33.9%] vs 40.0% [95% CI, 36.1%-44.0%]; P = .001; lipid-lowering medication: 25.3% [95% CI, 22.1%-28.7%] vs 39.6% [95% CI, 36.1%-43.2%]; P < .001). Women also had significantly higher pulse rates (mean [SD], 75.2 [6.8] beats per minute vs 71.8 [6.9] beats per minute; P < .001) and hemoglobin A1c levels (mean [SD], 8.3% [1.0%] vs 8.1% [1.0%]; P = .01) and achieved targets for tighter glycemic control less often than men (ie, hemoglobin A1c <7%: 11.2% [95% CI, 9.3%-13.3%] vs 14.0% [95% CI, 12.0%-16.3%]; P = .03). CONCLUSIONS AND RELEVANCE These findings suggest that despite a more favorable cardiometabolic risk factor profile, women with type 1 diabetes did not have a significantly lower CVD event burden than men, suggesting a greater clinical impact of cardiometabolic risk factors in women vs men with diabetes. These findings call for conscientious optimization of the control of CVD risk factors in women with type 1 diabetes.
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10.
Effect of a Personalized Diet to Reduce Postprandial Glycemic Response vs a Low-fat Diet on Weight Loss in Adults With Abnormal Glucose Metabolism and Obesity: A Randomized Clinical Trial.
Popp, CJ, Hu, L, Kharmats, AY, Curran, M, Berube, L, Wang, C, Pompeii, ML, Illiano, P, St-Jules, DE, Mottern, M, et al
JAMA network open. 2022;5(9):e2233760
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Postprandial glycaemic response (PPGR) to foods can be different from person to person. This could be the reason why people experience different weight loss outcomes with standardised diets such as a low glycaemic index diet, low-fat diet or a low carbohydrate diet. In this single-centre, population-based, randomised, blinded clinical trial, 204 participants with irregular glucose metabolism and obesity were randomised to consume either a low-fat or personalised diet for six months in combination with fourteen behavioural change counselling sessions. The participants in the personalised diet group received a colour-coded meal score to indicate their estimated PPGR for different foods. The results of this study showed no significant weight reduction in the personalised diet group compared to the low-fat diet. Further robust studies are required to develop appropriate precision nutrition interventions for weight loss and energy balance. However, healthcare professionals can use the results of this study to understand that both a low-fat diet and a personalised diet, coupled with behavioural counselling, may be effective in promoting weight loss in obese populations with irregular glucose metabolism.
Abstract
IMPORTANCE Interindividual variability in postprandial glycemic response (PPGR) to the same foods may explain why low glycemic index or load and low-carbohydrate diet interventions have mixed weight loss outcomes. A precision nutrition approach that estimates personalized PPGR to specific foods may be more efficacious for weight loss. OBJECTIVE To compare a standardized low-fat vs a personalized diet regarding percentage of weight loss in adults with abnormal glucose metabolism and obesity. DESIGN, SETTING, AND PARTICIPANTS The Personal Diet Study was a single-center, population-based, 6-month randomized clinical trial with measurements at baseline (0 months) and 3 and 6 months conducted from February 12, 2018, to October 28, 2021. A total of 269 adults aged 18 to 80 years with a body mass index (calculated as weight in kilograms divided by height in meters squared) ranging from 27 to 50 and a hemoglobin A1c level ranging from 5.7% to 8.0% were recruited. Individuals were excluded if receiving medications other than metformin or with evidence of kidney disease, assessed as an estimated glomerular filtration rate of less than 60 mL/min/1.73 m2 using the Chronic Kidney Disease Epidemiology Collaboration equation, to avoid recruiting patients with advanced type 2 diabetes. INTERVENTIONS Participants were randomized to either a low-fat diet (<25% of energy intake; standardized group) or a personalized diet that estimates PPGR to foods using a machine learning algorithm (personalized group). Participants in both groups received a total of 14 behavioral counseling sessions and self-monitored dietary intake. In addition, the participants in the personalized group received color-coded meal scores on estimated PPGR delivered via a mobile app. MAIN OUTCOMES AND MEASURES The primary outcome was the percentage of weight loss from baseline to 6 months. Secondary outcomes included changes in body composition (fat mass, fat-free mass, and percentage of body weight), resting energy expenditure, and adaptive thermogenesis. Data were collected at baseline and 3 and 6 months. Analysis was based on intention to treat using linear mixed modeling. RESULTS Of a total of 204 adults randomized, 199 (102 in the personalized group vs 97 in the standardized group) contributed data (mean [SD] age, 58 [11] years; 133 women [66.8%]; mean [SD] body mass index, 33.9 [4.8]). Weight change at 6 months was -4.31% (95% CI, -5.37% to -3.24%) for the standardized group and -3.26% (95% CI, -4.25% to -2.26%) for the personalized group, which was not significantly different (difference between groups, 1.05% [95% CI, -0.40% to 2.50%]; P = .16). There were no between-group differences in body composition and adaptive thermogenesis; however, the change in resting energy expenditure was significantly greater in the standardized group from 0 to 6 months (difference between groups, 92.3 [95% CI, 0.9-183.8] kcal/d; P = .05). CONCLUSIONS AND RELEVANCE A personalized diet targeting a reduction in PPGR did not result in greater weight loss compared with a low-fat diet at 6 months. Future studies should assess methods of increasing dietary self-monitoring adherence and intervention exposure. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT03336411.