– There is no significant increased risk of dementia among patients who use proton pump inhibitors, compared with those who don’t, results from a systematic meta-analysis suggest.

Dr. Saad Alrajhi, McGill University, Montreal Doug Brunk/MDedge News

Dr. Saad Alrajhi

The finding runs counter to recent studies, including a large pharmacoepidemiological claims data analysis from Germany, that propose an association between proton pump inhibitor (PPI) use and the development of dementia (JAMA Neurol. 2016;73[4]:410-6). “The issue with these studies is that they’re based on retrospective claims data and pharmacoepidemiological studies and insurance databases that don’t really give you a good causality basis,” lead study author Saad Alrajhi, MD, said in an interview at the annual Digestive Disease Week.

In an effort to better characterize the association between PPI exposure and dementia, Dr. Alrajhi, a gastroenterology fellow at McGill University, Montreal, and colleagues conducted a meta-analysis of all fully published randomized clinical trials or observational studies comparing use of PPIs and occurrence of dementia. The researchers queried Embase, MEDLINE, and ISI Web of Knowledge for relevant studies that were published from 1995 through September 2018. Next, they assessed the quality of the studies by using the Cochrane risk assessment tool for RCTs or the Newcastle-Ottawa Scale for observational studies.

As the primary outcome, the researchers compared dementia incidence after PPI exposure (experimental group) versus no PPI exposure (control group). Development of Alzheimer’s dementia was a secondary outcome. Sensitivity analyses consisted of excluding one study at a time, and assessing results among studies of highest qualities. Subgroup analyses included stratifying patients by age. To report odds ratios, Dr. Alrajhi and colleagues used fixed or random effects models based on the absence or presence of heterogeneity.

Of 549 studies assessed, 5 met the criteria for inclusion in the final analysis: 3 case-control studies and 2 cohort studies, with a total of 472,933 patients. All of the studies scored 8 or 9 on the Newcastle-Ottawa scale, indicating high quality. Significant heterogeneity was noted for all analyses. The researchers found that the incidence of dementia was not significantly increased among patients in the PPI-exposed group (odd ratio, 1.08 (95% confidence interval, 0.97-1.20; P = .18). Sensitivity analyses confirmed the robustness of the results. Subgroup analysis showed no between-group differences among studies that included a minimum age above 65 years (three studies) or less than age 65 (two studies). PPI exposure was not associated with the development of Alzheimer’s dementia (two studies) (OR, 1.32 (95% CI, 0.80-2.17; P = .27).

“In the absence of randomized trial evidence, a PPI prescribing approach based on appropriate utilization of guideline-based prescription should be done without the extra fear of the association of dementia,” Dr. Alrajhi said.

The researchers reported having no financial disclosures.