Claims‐Based Frailty and Outcomes: Applying an Aging Measure to Older Adults with Parkinson's Disease

Background Frailty is a geriatric syndrome with negative health impacts not captured by comorbidity and disability alone. The prevalence of frailty in Parkinson's disease (PD) has been described, but data on frailty‐associated outcomes are limited. Objective To describe the level of frailty and investigate the association between frailty and outcomes in a Medicare sample of persons diagnosed with PD. Methods We used the claims‐based frailty index to assess frailty in a cohort of Medicare beneficiaries with PD in 2013. Frailty was categorized as non‐frail/pre‐frail, mildly frail, moderately frail, and severely frail. Adjusted logistic regression models examined the relationship between frailty and mortality, hospitalization, emergency department visits, and fall‐related injuries through 2014. Results Of 62,786 beneficiaries with PD in 2013, 55.3% were frail. Frail individuals were more likely to be female, older, Black, metropolitan dwelling, without neurologist care, nursing facility residents, or multimorbid. The average daily levodopa equivalent dose initially increased, then decreased from the pre‐frail to the severely frail groups. Compared to non‐frail/pre‐frail persons, severely frail persons had higher adjusted odds of 1‐year mortality (AOR 2.74, 95% CI 1.98, 3.78), hospitalization (AOR 2.34, 95% CI 1.74, 3.14), emergency department visits (AOR 2.97, 95% CI 2.14, 4.13), and fall‐related injury (AOR 1.43, 95% CI 0.90, 2.26). Conclusions Frailty is common and differentially distributed among older adults with PD. Frailty in PD is associated with adverse health outcomes and death. Observational study analyses may benefit from adjustment for frailty; claims‐based frailty surveillance may identify vulnerable PD patients in health system, registry, or administrative data. © 2021 International Parkinson and Movement Disorder Society