Study Finds Diabetes Complications and Mental Health Disorders Are a 2-Way Street

Brian Callaghan, MD, MS
Credit: Michigan Medicine

New research from Michigan Medicine and the University of Michigan (U-M School of Public Health is shedding further light on the relationship between diabetes complications and mental health disorders, with results suggesting the relationship goes both ways.¹

“We wanted to see if chronic diabetes complications led to mental health disorders or if mental health disorders led to those diabetes complications – but we found that both relationships are true,” said senior investigator Brian Callaghan, MD, MS, the Eva L. Feldman, MD, PhD, Professor of Neurology at U-M Medical School.² “The findings highlight a need for clinicians to actively screen for mental health disorders in patients with diabetes in addition to screening for chronic complications, which is the recommended standard of care in diabetes.”

Citing an interest in the further exploration of the relationship between mental health disorders and chronic diabetes complications, Callaghan and a team of colleagues designed the current research endeavor as an analysis of insurance claims data from the Optum Clinformatics Data Mart Database from 2001 through 2018. Using ICD-9 and -10 codes, investigators identified 44,735 individuals with type 1 diabetes and 152,187 individuals with type 2 diabetes for inclusion in the study. Investigators used common-referent group propensity scoring to match individuals with type 1 diabetes to individuals with type 2 diabetes and individuals without diabetes, with matching stratified by age group and propensity scores calculated using age at study entry, sex, race/ethnicity, geographic region, education level, net worth, insurance plan type, high-deductible health plan status, modified Charlson comorbidity index, starting year of enrollment, and length of follow-up.¹

In total, 356,630 patients without diabetes were identified for inclusion in the study. Investigators pointed out characteristics of individuals were closely matched across the 3 groups. Investigators also pointed out the proportion of female participants was 47.5%, 46.0%, and 51.8% for the type 1, type 2, and no diabetes groups, respectively, and the majority of each group, 74.1%, 76.5%, and 76.7%, respectively, identified as White.¹

For the purpose of analysis, investigators fit Cox proportional hazards models with time-varying diagnoses of chronic diabetes complications or mental health disorders to investigate their associations with developing mental health conditions or chronic diabetes complications, respectively. Mental health disorders of interest for the study included anxiety and depression. The chronic diabetes complications of interest for the study included neuropathy, retinopathy, nephropathy or diabetic kidney disease, stroke, myocardial infarction, peripheral vascular disease, and amputation.¹

Upon analysis, results indicated having a chronic diabetes complication was associated with a near doubling or more for risk of developing a mental health disorder, with the greatest risk observed among the oldest age group.¹

• Age 0 to 19 years: HR, 2.1; 95% CI, 1.4 to 3.2
• Age 20 to 39 years: HR, 1.9; 95% CI, 1.6 to 2.4
• Age 40 to 59 years: HR, 2.1; 95% CI, 1.8 to 2.5
• Age 60+ years: HR 2.9; 95% CI, 2.4 to 3.4

When assessing risk of chronic diabetes complication with mental health disorders, investigators found risk was significantly increased all groups, but the magnitude of effect decreased age 0 to 19 years (HR, 2.5; 95% CI, 1.7 to 3.7) to 20 to 39 years (HR, 1.5; 95% CI, 1.2 to 2.9) but remained relatively stable to age 40 to 59 years (HR, 1.4; 95% CI, 1.2 to 1.7) and 60 years or older (HR, 1.6; 95% CI, 1.3 to 1.8).¹

Further analysis demonstrated less than 60 years of age, people with type 1 diabetes were more likely to have chronic diabetes complications while their counterparts with type 2 diabetes were more likely to have mental health disorders. However, investigators noted the relationship between chronic diabetes complications and mental health disorders in either direction was not affected by diabetes type (P > 0.05 for interaction effects).¹

“Most likely, a combination of direct and indirect effects and shared risk factors drive the association we are seeing,” said lead investigator Maya Watanabe, MD, a biostatistician at the Harvard T.H. Chan School of Public Health and former graduate student research assistant at U-M.² “Diabetes care providers may be able to simultaneously prevent the risk of multiple complications by providing interventions to treat these shared risk factors.” 

References:

1. Watanabe M, Reynolds EL, Banerjee M, et al. Bidirectional Associations Between Mental Health Disorders and Chronic Diabetic Complications in Individuals With Type 1 or Type 2 Diabetes. Diabetes Care. Published online July 15, 2024. doi:10.2337/dc24-0818
2. Michigan Medicine. Mental health and chronic diabetes complications strongly linked both ways, study finds. Michigan Medicine. August 22, 2024. Accessed August 26, 2024. https://www.michiganmedicine.org/health-lab/mental-health-and-chronic-diabetes-complications-strongly-linked-both-ways-study-finds.