Among adults with type 2 diabetes, a combination of heavy alcohol consumption and depression increases the risk for coronary artery disease and neuropathy, according to findings published in Diabetes.
“When examining the association between alcohol consumption and complications, it may be relevant to consider depression, given that heavy alcohol use is more common in individuals with high depressive symptoms than in the general population,” Norbert Schmitz, PhD, a professor in the department of psychiatry and an associate member in the department of epidemiology and biostatistics at McGill University in Montreal, and colleagues wrote. “Moreover, high depressive symptoms are more common in individuals with [type 2 diabetes] compared to the general population and are also associated with complications.”
Schmitz and colleagues analyzed data from 1,413 adults with type 2 diabetes aged 40 to 76 years participating in five waves of the Evaluation of Diabetes Treatment study, an annual telephone survey conducted in Quebec, Canada (mean age, 60 years; 50% women). Respondents provided information on alcohol use (assessed via the Alcohol Use Disorders Identification Test-Concise), depressive symptoms (assessed via the Patient Health Questionnaire-9) and diabetes-related complications (via the Diabetes Complications Index) annually. Researchers used multiple logistic regression analyses with generalized estimating equations to examine associations between frequency of alcohol use, depressive symptoms and risk for incident diabetes-related complications.
Within the cohort, 958 reported drinking within the past year. The mean depressive symptom score was 4.1 (scores range from 0-27, with higher scores indicating more severe depression).
Researchers observed a 9% increase in the odds of developing neuropathy for every unit increase in depressive symptoms and a 10% decrease in the odds of developing neuropathy for every unit increase in alcohol frequency. The interaction between depressive symptoms and alcohol frequency was positively associated with increased odds of developing neuropathy.
Similarly, researchers observed a 9% increase in risk for developing CAD for every unit increase in depressive symptoms, but there was no association observed between alcohol frequency and odds of developing CAD. The interaction between alcohol frequency and depressive symptoms was positively related to increased odds of developing CAD. After adjustment for covariates, odds for developing CAD were no longer related to depressive symptoms, but researchers observed an 18% decrease in odds of developing CAD for every unit increase in alcohol frequency, with the interaction between depressive symptoms and alcohol frequency with CAD remaining positively significant.
Those with depression who reported drinking most frequently had the highest risk for neuropathy (OR = 1.02; 95% CI, 1-1.04) and CAD (OR = 1.02; 95% CI, 1-1.04) vs. those who did not consume alcohol and did not have depression, with results persisting after adjustment for age, sex, level of education, marital status, diabetes duration and smoking status.
The researchers noted that several mechanisms may link alcohol consumption to diabetes-related complications.
“Whereas acute alcohol consumption may not have any significant long-term effects on glucose in individuals with [type 2 diabetes], chronic heavy alcohol use may result in changes in glucose levels, insulin resistance, changes in lipid levels, mitochondrial dysfunction and interference in cell signaling,” the researchers wrote. “Additionally, individuals with [type 2 diabetes] who drink heavily are also more likely to engage in poorer self-management behaviors, including poorer medication adherence, diet and exercise, compared to those who drink less. Through these metabolic, cell signaling and self-management changes, heavy alcohol use can increase the risk of complications.”
Neither depressive symptoms nor alcohol frequency was associated incidence of retinopathy, and there was no observed interaction between depressive symptoms and alcohol frequency on the odds of developing nephropathy, according to researchers.
“The present results suggest that individuals should be screened not only for frequency of alcohol consumption, but also for depressive symptoms when evaluating risk of diabetes-related complications, as the combination of high alcohol frequency and high depressive symptoms could lead to an even greater risk of neuropathy and CAD,” the researchers wrote. – by Regina Schaffer
Disclosures: The authors report no relevant financial disclosures.