CHARLESTON, SC — Costs of treating diabetes increase when patients also have mental health issues, according to a new VHA study.

The study, which was published recently in the American Journal of Managed Care, looked at the prevalence and specific costs associated with discrete multimorbid mental health disease clusters in adults with diabetes mellitus (DM).1

Researchers from the Center for Health Disparities Research at the Medical University of South Carolina in Charleston conducted a longitudinal analysis of a retrospective cohort of 733,071 VA patients with DM between 2002 and 2006. Mental health comorbidities (MHCs) included in the study were depression, substance abuse, and psychosis.

Study authors said their primary outcomes of interest were total inpatient, outpatient and pharmacy costs measured in 2012 dollars from the perspective of the VHA.

Results indicated that DM was present with comorbid depression, substance abuse and psychosis in 12.1%, 3.7% and 4.2% of patients, respectively. Overall, 13.5% of patients had 1 MHC, 2.5% had 2 MHCs, and 0.5% had all MHCs.

The study pointed out that total inpatient ($1,435,651,415), outpatient ($366,137,435) and pharmacy ($90,064,725) costs were highest for patients with DM and comorbid depression alone. At the per-patient level, DM plus psychosis and substance abuse had the highest inpatient cost, with $35,518.

At the same time, DM plus all MHCs had the highest outpatient costs ($6,962), and DM plus depression and psychosis had the highest pharmacy costs ($1753).

“DM with comorbid depression is the most prevalent MHC combination and is associated with the highest total VHA healthcare costs,” study authors wrote. “However, other comorbidity clusters are associated with higher mean per patient costs, and may therefore benefit from more intensive intervention. Analysis of healthcare expenditures by multi-morbid disease clusters can be a useful tool for healthcare policy planning.”

  1. Egede LE, Gebregziabher M, Zhao Y, Dismuke CE, Walker RJ, Hunt KJ, Axon RN. Differential impact of mental health multimorbidity on healthcare costs in diabetes. Am J Manag Care. 2015 Aug;21(8):535-44. PubMed PMID: 26295353.