Impact of dementia on costs of modifiable comorbid conditions.

Objectives: To use the CMS 5% data sample to explore the impact of Alzheimer disease and other dementias (ADOD) on individual and population costs of certain potentially modifiable comorbid conditions, in order to assist in the design of population health management (PHM) programs for individuals with ADOD.

Study Design: A cross-sectional retrospective analysis was performed on parts A and B claims data of 1,056,741 Medicare beneficiaries 65 years and older with service dates in 2010.

Methods: The primary analysis compared the prevalence and costs of 15 comorbid conditions among those with and without ADOD in the entire sample of 1,056,741; in addition, a subset of beneficiaries without ADOD were matched by age, sex, and race on a 1:1 basis to beneficiaries with ADOD. Prevalence and cost ratios were calculated to examine the impact of potentially modifiable study comorbid conditions in both populations.

Results: The prevalence of ADOD in the entire sample was 9.4%, and their costs represented 22.8% of the total. In the matched sample, all 15 comorbid conditions chosen for the study were more prevalent and showed higher mean individual costs in beneficiaries with ADOD compared with those without. The ADOD population also had higher costs and prevalence than the non-ADOD population when single comorbid conditions were examined separately. Study conditions with the highest individual cost ratios were urinary tract infections (UTIs), diabetes with complications, and fractures. Study conditions with the highest population cost ratios were fractures, UTIs, and diabetes without complications.

Conclusions: Prevalence and costs of all study comorbidities were higher in beneficiaries with ADOD compared with those without. Individual cost ratios and population cost ratios may be useful for PHM programs trying to cost-effectively manage individuals with ADOD and comorbid chronic conditions.