Plain language summary
Helicobacter pylori (H. pylori) is a bacterium that can cause infection in the digestive tract. H. pylori can reduce the uptake of nutrients such as folate and iron and cause inflammation. The aim of this study was to explore potential interactions between certain nutrients and H. pylori in cognitive function. Blood samples were taken from adults aged 60 to 85, and tested for H. pylori, active folate as 5-Methyltetrahydrofolate (5-MTHF), vitamin B12 and homocysteine. Cognitive function was measured using a digit symbol coding (DSC) test. 41% of the participants tested positive for H. pylori. H. pylori, 5-MTHF, vitamin B-12 and homocysteine were not associated individually with performance on the DSC task. However, H. pylori interacted with 5-MTHF concentration to predict performance on the DSC task; those with H. pylori performed worse on the DSC task as 5-MTHF concentration decreased. The authors concluded that the interaction between H. pylori and 5-MTHF might impair aspects of cognitive function. This finding might be especially relevant to vulnerable groups such as pregnant women and the elderly.
Abstract
OBJECTIVE To explore potential interactions between folate-cycle factors and Helicobacter pylori seropositivity in the prediction of cognitive function. METHODS We used data obtained from the 1999-2000 continuous National Health and Nutrition Examination Survey produced by the United States' Centers for Disease Control and Prevention. Using Ordinary Least Squares regression, we tested for associations between multiple folate-cycle factors, Helicobacter pylori seropositivity, and cognitive function assessed by the digit symbol coding subtest of the Wechsler Adult Intelligence Scale-III. We then tested for interactions between each of the folate-cycle factors and Helicobacter pylori in the prediction of cognitive function. RESULTS Although Helicobacter pylori seropositivity, 5-methyltetrahydrofolate, vitamin B-12, and homocysteine were not associated with performance on the digit symbol coding task, Helicobacter pylori seropositivity interacted with 5-methyltetrahydrofolate concentration to predict performance on the digit symbol coding task. The Helicobacter pylori seropositive group performed worse on the digit symbol coding task as 5-methyltetrahydrofolate concentration decreased. CONCLUSION The interaction between Helicobacter pylori seropositivity and reduced folate-cycle factor 5-methyltetrahydrofolate might impair aspects of cognitive function.
Methodological quality
Allocation concealment
:
Not applicable
