Effect of Gastric Acid Suppressants on Response to a Physical Activity Intervention and Major Mobility Disability in Older Adults: Results from the Lifestyle Interventions for Elders (LIFE) Study

Objectives Proton pump inhibitors (PPIs) and histamine(2) receptor antagonists (H2RAs) are associated with pharmacologic effects that may be detrimental to mobility and response to physical activity. Mobility disability and injurious fall outcomes in PPI and H(2)RA users were compared with nonusers in this secondary analysis of data from the Lifestyle Interventions for Elders (LIFE) study. Methods Participants ages 70-89 years were randomized to a physical activity (PA) or successful aging intervention and evaluated by medication use. Confounders included baseline demographic characteristics, physical function, cognitive function, sleep quality, and acid reflux symptoms that were adjusted via propensity score weighting. Outcomes were incident and persistent major mobility disability (MMD and pMMD) and injurious falls. Weighted proportional hazard models evaluated independent and interaction effects of PPIs and H2RAs. Results No interaction was found between PPIs and H2RAs and the PA intervention. Drug use associations were significant for H2RAs (hazard ratio [HR] 1.74 [95% confidence interval [CI] 1.12-2.68]) and PPIs (HR 1.32 [95% CI 1.02-1.70]) compared with nonusers for pMMD. PPIs were associated with increased injurious falls compared with nonusers (HR 1.44 [95% CI 1.06-1.96]). Pooling of data from the H(2)RA and PPI exposure groups showed a 26% increase in MMD (HR 1.26 [95% CI 1.07-1.48]), a 44% increase in pMMD (HR 1.44 [95% CI 1.16-1.77]), and a 48% increase in injurious falls (HR 1.48 [95% CI 1.15-1.91]) compared with nonusers. All direct comparisons between PPIs and H2RAs were nonsignificant. Conclusions Compared with nonusers, participants using either PPIs or H2RAs had an increased risk of MMD, pMMD, and injurious falls. It is not known if these effects are related to the individual pharmacology of each medication, reduced acid secretion, or the underlying disease state. Further study is required to determine causality.