Healthcare costs in patients with diabetes mellitus and comorbid mental disorders—a systematic review

Abstract

Aims/hypothesis We systematically reviewed the impact of comorbid mental disorders on healthcare costs in persons with diabetes. Method We conducted a comprehensive search for studies investigating adult persons (≥18 years old) with diabetes mellitus. All studies that allowed comparison of healthcare costs between diabetic patients with mental disorders and those without were included. Results We identified 4,273 potentially relevant articles from a comprehensive database search. Of these, 31 primary studies (39 publications) fulfilled inclusion criteria, of which 27 examined comorbid depression. Hospitalisation rates and hospitalisation costs, frequency and costs of outpatient visits, emergency department visits, medication costs and total healthcare costs were mainly increased with small to moderate effect sizes in patients with diabetes and comorbid mental disorders compared with diabetic patients without such problems. Frequency (standardised mean difference [SMD]=0.35-1.26) and costs (SMD= 0.33-0.85) of mental health specialist visits were increased in the group with mental health comorbidity. Results regarding diabetes-related preventive services were inconsistent but point to a reduced utilisation rate in diabetic patients with comorbid mental disorders. Statistical heterogeneity between studies was high (I 2 range 64-98%).Pooled overall effects are therefore not reported. Studies included differ substantially regarding sample selection, assessment of diabetes and comorbid mental disorders, as well as in assessment of cost variables. Conclusions/interpretation In light of the increased healthcare costs and inadequate use of preventive services, comorbid mental disorders in patients with diabetes must become a major focus of diabetes healthcare and research.

Depression in Adults in the T1D Exchange Clinic Registry

“…Of those we assessed, female sex, African American race or Hispanic ethnicity, low education (i.e., less than high school), being unemployed, being without health insurance coverage, low socioeconomic status, and medical illness are consistently viewed as significant risk factors (24,30), as they were shown to be in this study. For patients with type 2 diabetes, the literature shows that those who are poorer, less educated, unemployed, without insurance, and who have more complications are more likely to be depressed (6)(7)(8)(9)(10)(11)13,14). We found similar results in our sample of adults with T1D.…”

“…, greater risk of severe hypoglycemia (SH) (12), higher healthcare costs (13,14), and poorer quality of life (15). Most studies and meta-analyses include only people with type 2 diabetes or combine type 1 and type 2 diabetic participants without reporting data separately for each group.…”

Implications of comorbidity for primary care costs in the UK: a retrospective observational study

“…Studies looking at the impact of comorbid mental health problems on the use of healthcare resources by patients with diabetes have found that in general primary care and secondary care costs increase in the presence of comorbid mental health problems. 22,23,24 The combination of diabetes and depression was found to be greatly cost-increasing; diabetes and mental health was cost-limiting in the study sample, however, mental health as defined under the QOF relates to more severe conditions (for example schizophrenia and long-term psychosis) rather than common mental health problems such as depression. Nichols and Brown 9 found patients with both diabetes and cardiovascular disease had higher total costs than the sum of costs for patients with only cardiovascular disease or only diabetes.…”

Medical expenditures associated with major depressive disorder among privately insured working-age adults with diagnosed diabetes in the United States, 2008

“…Because of the severity of depression, persons with ITDM may be vulnerable to self-monitoring their blood glucose less frequently than they should [16] and to subsequent diabetes complications [11,15]. Thus, excess costs are very likely to be influenced by the interaction between depression and diabetes treatment mode [17]. In terms of antidepressant medication use, those who were on medication might have more severe depression symptoms, thus they might incur larger costs than those who were not on antidepressant medication.…”