The costs of treating dementia among American Indians with diabetes within the Indian Health Service and Tribal health programs

Abstract Background American Indian and Alaska Native (AI/AN) adults have one of the highest prevalence of diabetes (14.7%) in the United States, nearly double that of the White population. As AI/ANs age, they are at high risk for chronic diseases that have diabetes as a well‐established risk factor, such as cardiovascular complications and dementia. Approximately half of AI adults with dementia have diabetes, but little is known about their treatment costs. Our aims were to profile treatment costs of AI adults with diabetes, with and without dementia, and to understand how dementia influences costs by type of service. Method We analyzed fiscal year 2013 treatment cost data from the Indian Health Service and Tribal health programs for American Indian (AI) adults aged ≥65 years with diabetes. Using data for 921 adults with dementia and a matched sample without dementia (n = 921), matched by age, sex, and location, we report actual and adjusted total treatment costs and costs by service type. Adjusted costs were estimated using a generalized linear model with a log link function and gamma distribution. Results The morbidity burden of AI adults with both diabetes and dementia was high. Over seventy percent (71.4%) had cardiovascular disease (CVD) and 39.4% had renal disease. The prevalence of these conditions was lower (57.8% and 30.6%, respectively) among adults with diabetes without dementia. Mean total treatment cost was higher for adults with dementia ($15,978) than for adults without dementia ($8,857), a difference of $7,121. The difference in adjusted total treatment costs between adults with and without dementia was $3,891 (95% confidence interval [CI]: $2,122‐$5,659), most of which was due to the difference in hospital inpatient costs ($3,754; 95% CI: $2,221‐$5,286). Furthermore, among adults with both dementia and CVD, adjusted hospital inpatient costs were $8,114 (95% CI: $6,018‐$10,211), significantly higher than that among adults with dementia only ($2,075; 95% CI: $992‐$3,158) and among adults with CVD only ($3,050; 95% CI: $2,399‐$3,701) (Figure 1). Conclusion Knowing CVD is strongly associated with high inpatient costs among AI adults with both diabetes and dementia may inform enhancements to outpatient and home‐based services that address their CVD health risks.