Can disease management target patients most likely to generate high costs? The impact of comorbidity.

Context: Disease management programs are increasingly used to manage costs of patients with chronic disease.

Objective: We sought to examine the clinical characteristics and measure the health care expenditures of patients most likely to be targeted by disease management programs.

Design: Retrospective analysis of prospectively obtained data.

Setting: A general medicine practice with both faculty and residents at an urban academic medical center.

Participants: Five thousand eight hundred sixty-one patients enrolled in the practice for at least 1 year.

Main Outcomes: Annual cost of diseases targeted by disease management.

Measurements: Patients' clinical and demographic information were collected from a computer system used to manage patients. Data included diagnostic information, medications, and resource usage over 1 year. We looked at 10 common diseases targeted by disease management programs.

Results: Unadjusted annual median costs for chronic diseases ranged between $1,100 and $1,500. Congestive heart failure ($1,500), stroke ($1,500), diabetes ($1,500), and cancer ($1,400) were the most expensive. As comorbidity increased, annual adjusted costs increased exponentially. Those with comorbidity scores of 2 or more accounted for 26% of the population but 50% of the overall costs.

Conclusions: Costs for individual chronic conditions vary within a relatively narrow range. However, the costs for patients with multiple coexisting medical conditions increase rapidly. Reducing health care costs will require focusing on patients with multiple comorbid diseases, not just single diseases. The overwhelming impact of comorbidity on costs raises significant concerns about the potential ability of disease management programs to limit the costs of care.