Association of Healthy Lifestyle and Incident Polypharmacy.

Background: Polypharmacy, commonly defined as taking ≥5 medications, is an undesirable state associated with lower quality of life. Strategies to prevent polypharmacy may be an important priority for patients. We sought to examine the association of healthy lifestyle, a modifiable risk factor, with incident polypharmacy.

Methods: We performed a secondary analysis of the REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort study, including 15,478 adults aged ≥45 years without polypharmacy at baseline. The primary exposure was healthy lifestyle at baseline as measured by the Healthy Behavior Score (HBS), a cumulative assessment of diet, exercise frequency, tobacco smoking, and sedentary time. HBS ranges from 0-8, whereby 0-2 indicates low HBS, 3-5 indicates moderate HBS, and 6-8 indicates high HBS. We used multinomial logistic regression to examine the association between HBS and incident polypharmacy, survival without polypharmacy, and death.

Results: Higher HBS (i.e., healthier lifestyle) was inversely associated with incident polypharmacy after adjusting for sociodemographic and baseline health variables. Compared with participants with low HBS, those with moderate HBS had lower odds of incident polypharmacy (odds ratio [OR] 0.85; 95% confidence interval [CI], 0.73-0.98) and lower odds of dying (OR 0.74; 95% CI, 0.65-0.83). Participants with high HBS had even lower odds of both incident polypharmacy (OR 0.75; 95% CI, 0.64-0.88) and death (OR 0.62; 95% CI, 0.54-0.70). There was an interaction for age, where the association between HBS and incident polypharmacy was most pronounced for participants aged ≤65 years.

Conclusions: Healthier lifestyle was associated with lower risk for incident polypharmacy.