Background: Advances in antiretroviral therapy have extended the lifespan of people living with HIV, increasing age-related comorbidities and polypharmacy. This study aimed to examine how frailty is associated with co-medication network structure and anticholinergic burden in adults living with HIV.
Methods: This cross-sectional study analysed co-medication networks across robust, prefrail, and frail states using data from the Positive Brain Health Now cohort of adults aged ≥35 years. Frailty was assessed using a modified Fried Frailty Phenotype. Network metrics such as density (proportion of observed to possible medication-medication connections), clustering coefficient, and assortativity were calculated to characterize structural differences. Exponential Random Graph Models (ERGMs) assessed the relationship between anticholinergic burden and co-medication patterns, and permutation tests evaluated differences in network metrics between frailty states.
Results: Network density was very similar across frailty groups (0.148 in the robust group vs 0.160 in the prefrail and frail groups). The clustering coefficient increased slightly from robust (0.42) to frail (0.44) states (p < 0.001), indicating somewhat tighter connectivity among medications in frail individuals. ERGM analyses showed that a one-unit increase in anticholinergic burden reduced the likelihood of co-medication by 43.8% in robust individuals, 44.3% in prefrail individuals, and 47.7% in frail individuals, with significant differences between robust and frail groups (p < 0.001).
Conclusion: Frailty is associated with modest but distinct differences in co-medication network structure and the influence of anticholinergic burden. Early interventions in robust and prefrail states, along with tailored strategies for frail individuals, might help mitigate medication-related risks.
Keywords: Anticholinergics; Frailty; HIV; Network analysis; Polypharmacy.
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