Health service utilization among Alzheimer's disease patients: evidence from managed care.

BACKGROUND: The objective of this study was to assess the disease burden of Alzheimer's disease (AD) in a commercial managed care setting by comparing direct health care costs and adverse event outcomes between patients with AD and without AD.
METHODS: The study design used eligibility, medical, and pharmacy claims data from a large, national, geographically diverse, fee-for-service U.S. managed health plan. Commercially insured patients aged 65 years and older with a pharmacy benefit with evidence of AD (n = 4,450) and a control group without AD (n = 13,650) were matched by age, gender, plan location, and length of enrollment. Adverse event outcomes, comorbid conditions, and annualized health care costs were compared. Incremental costs were calculated by using a two-part model to estimate the burden of illness; incremental cost confidence intervals were estimated by bootstrap analysis.
RESULTS: Patients with AD had generally higher health care costs and higher risk of acute adverse outcomes than the control cohort. Annual adjusted total health care costs per patient were approximately $1,418 greater for the AD cohort. Patients with AD had an unadjusted fracture risk of 14.6% versus 6.2% in the matched cohort and accidental injury/falls risk of 27.4% versus 11.4%.
CONCLUSIONS: Few studies have examined the disease burden of AD in commercial managed care settings. Similar to results of comparative studies with Medicare data, the disease burden is greater for patients with AD compared with a matched control cohort, with a different mix and a greater number of comorbid health care conditions partially accounting for this difference. As membership in commercial and Medicare managed care plans increases, plans will need to develop effective mechanisms to manage the health care of high-risk, high-cost patients with AD.