UMMS Affiliation

Department of Quantitative Health Sciences; Center for Health Policy and Research

Publication Date


Document Type



Aged; Aged, 80 and over; Alzheimer Disease; Cohort Studies; Comorbidity; Cost of Illness; Diagnosis-Related Groups; Emergency Medical Services; Female; Health Care Costs; Humans; Male; Medicare; Patient Admission; United States; Utilization Review


Biostatistics | Epidemiology | Health Services Research


BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disorder incurring significant social and economic costs. This study uses a US administrative claims database to evaluate the effect of AD on direct healthcare costs and utilization, and to identify the most common reasons for AD patients' emergency room (ER) visits and inpatient admissions.

METHODS: Demographically matched cohorts age 65 and over with comprehensive medical and pharmacy claims from the 2003-2004 MEDSTAT MarketScan Medicare Supplemental and Coordination of Benefits (COB) Database were examined: 1) 25,109 individuals with an AD diagnosis or a filled prescription for an exclusively AD treatment; and 2) 75,327 matched controls. Illness burden for each person was measured using Diagnostic Cost Groups (DCGs), a comprehensive morbidity assessment system. Cost distributions and reasons for ER visits and inpatient admissions in 2004 were compared for both cohorts. Regression was used to quantify the marginal contribution of AD to health care costs and utilization, and the most common reasons for ER and inpatient admissions, using DCGs to control for overall illness burden.

RESULTS: Compared with controls, the AD cohort had more co-morbid medical conditions, higher overall illness burden, and higher but less variable costs ($13,936 s. $10,369; Coefficient of variation = 181 vs. 324). Significant excess utilization was attributed to AD for inpatient services, pharmacy, ER visits, and home health care (all p < 0.05). In particular, AD patients were far more likely to be hospitalized for infections, pneumonia and falls (hip fracture, syncope, collapse).

CONCLUSION: Patients with AD have significantly more co-morbid medical conditions and higher healthcare costs and utilization than demographically-matched Medicare beneficiaries. Even after adjusting for differences in co-morbidity, AD patients incur excess ER visits and inpatient admissions.

DOI of Published Version



BMC Health Serv Res. 2008 May 22;8:108. Link to article on publisher's site

Journal/Book/Conference Title

BMC health services research

PubMed ID


Related Resources

Link to Article in PubMed



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