An analysis of protective health behavior and polypharmacy among older patients: a nationwide cohort study

This study analyzed the relationship between protective health behaviors and polypharmacy in individuals aged 65 years and older.

We used data from a nationwide survey (KNHANES) from 2012 to 2016 in conjunction with the health insurance claims databases. A total of 3297 adults aged 65 or older were included in the study. Polypharmacy was defined as more than 30 prescription days in 6 months with five or more different drugs. Health-related behaviors (BMI, smoking, drinking, regular walking, and living alone) were extracted for 6 months before measuring polypharmacy. We used multivariable logistic regression on polypharmacy for each protective health behavior, as well as a composite score of protective health behavior. Subgroup analysis was also conducted by age and sex.

Among protective health behaviors, BMI < 25 (OR, 0.76; 95% CI, 0.66-0.88) and never smoking (OR, 0.78; 95% CI, 0.62-0.98) were associated with a lower risk of polypharmacy. Polypharmacy was significantly associated with BMI < 25 in both sex subgroups (male: OR, 0.71; 95% CI, 0.56-0.88; female: OR, 0.81; 95% CI, 0.67-0.99) and 65-79 subgroup (OR, 0.74; 95% CI, 0.63-0.86). The association between never smoking and polypharmacy was only significant in the 65-79 subgroup (OR, 0.71; 95% CI, 0.55-0.91). Participants with five protective health behaviors had a lower risk of polypharmacy than participants with zero or one health behavior, which was only statistically significant in the subgroup analysis of participants aged 65-79 years (OR, 0.52; 95% CI, 0.29-0.94).

This study finds that health behaviors such as obesity and smoking are associated with a higher risk of polypharmacy. Furthermore, we confirm that a high score of protective health behaviors is associated with a lower risk of polypharmacy. Our findings indicate the need for geriatric-centered management of protective health behaviors to prevent polypharmacy.