When performing retrospective studies, many times a potential association can be found with medications or diet and specific problems. When these risks/associations are low (i.e. relative risks <2), often, these findings do not hold up, particularly with prospective studies which are much more able to control for confounding variables.
For proton pump inhibitors (PPIs), many potential complications have been suggested at low relative risk findings in poorly-controlled studies. A recent study has contradicted previous findings suggesting that PPIs increase the risk of dementia.
Goldstein FC, et al. J Am Geriatr Soc. 2017;doi:10.1111/jgs.14956. (Thanks to Ben Gold for this reference)
A link and an excerpt from a summary of this study from Healio Gastroenterology:
They evaluated 10,486 volunteers within the NIH-supported Alzheimer’s Disease Centers who were aged 50 years and older and had either normal cognition or mild cognitive impairment at baseline. Participants underwent neuropsychological evaluations and self-reported PPI use at two to six annual visits between 2005 and 2015.
Overall, 884 reported they were taking PPIs at every visit, 1,925 reported they took PPIs intermittently, and 7,677 never reported taking PPIs.
Those who reported continuous PPI use showed a lower risk for cognitive function decline compared with those who never reported using PPIs (HR = 0.78; 95% CI, 0.66-0.93) as well as a lower risk for developing mild cognitive impairment or Alzheimer’s disease (HR = 0.82; 95% CI, 0.69-0.98).
Those who reported using PPIs intermittently also showed a lower risk for cognitive function decline (HR = 0.84; 95% CI, 0.76–0.93) and for developing mild cognitive impairment or Alzheimer’s disease (HR = 0.82; 95% CI, 0.74–0.91).
My take: This study provides reassurance that PPIs are unlikely to result in cognitive decline. Particularly when a study suggests a low risk of an association, further studies are needed to clarify the true risks.
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