Treated Behavioral Symptoms and Mortality in Medicare Beneficiaries in Nursing Homes with Alzheimer's Disease and Related Dementias

OBJECTIVES: To assess changes in behavioral symptoms associated with Alzheimer's disease and related dementias (ADRDs) after antipsychotic (AP) or antidepressant (AD) treatment and to estimate the effect of treatment response on mortality risk. DESIGN: Retrospective cohort study using 2006-2009 Medicare administrative and prescription drug claims data linked to Minimum Data Set 2.0. SETTING: Long-stay (>= 101 days) nursing home residents. PARTICIPANTS: Continuously enrolled fee-for-service Medicare beneficiaries who had ADRDs, initiated (no use in prior 6 months) AP (n = 2,035) or AD (n = 1,661) treatment during or after one or more behavioral symptoms (verbally abusive, physically abusive, socially inappropriate or disruptive behavior) presented, and had reassessment of behavioral symptoms after 3 consecutive months of the initiated treatment. MEASUREMENTS: Behavioral symptom change was measured according to score (range 0-9, based on number and frequency of symptoms) change between baseline and reassessment (improved, <0; unchanged, 0; worsened, >0). Survival analyses were conducted on time to death after reassessment, comparing residents whose symptoms improved with those whose symptoms remained unchanged or worsened. RESULTS: APs and ADs were comparable in treatment effectiveness, as evidenced by more than 85% of the behavioral symptom episodes in each cohort improving or remaining stable. Mortality risk was lower in both cohorts (AP: adjusted hazard ratio (aHR(AP)) = 0.93, 95% confidence interval (CI) = 0.81-1.07; AD: aHR(AD) = 0.82, 95% CI = 0.70-0.97) for residents whose symptoms improved than for those whose symptoms unchanged or worsened. CONCLUSION: ADs may be reasonable pharmacological alternatives to APs in clinical management of ADRD-related behavioral symptoms. Initial treatment response may alter medication-associated mortality risk. Further study is needed to confirm findings using other data and behavioral symptom-specific instruments.