Patients who have diabetes with depression are at higher risk; patients who have diabetes should be screened for psychological risk factors.
Diabetes can influence a patient’s life dramatically, including their state of mind. Social isolation and negative impacts on mental health can be a result of having diabetes. Previous studies had found an association with type 2 diabetes and depression. They showed that patients who have both are at higher risk for all-cause mortality and cardiovascular mortality compared to patients who do not have depression. A previous meta-analysis that assessed 5 studies from 2005-2012 showed that there is a 39% increased risk of cardiovascular mortality in patients who have both conditions.
This meta-analysis was designed to provide an update to further analyze the relationship between type 2 diabetes and depression. They reviewed PUBMED/MEDLINE, Medscape, Cochrane Library, CINAHL, EMBASE, and Scopus for articles that contained the following keywords: “depression” or “depressive disorder,” combined with “cardiac mortality” or “cardiovascular disease” or “macrovascular complications” or “stroke.” They included observational studies that enrolled patients with type 2 diabetes and a clinical history of depression, and were written in English. Those studies were published from 1985 until 2018. For statistical analysis, they used studies that reported hazard ratios to assess patients with type 2 diabetes and depression vs type 2 diabetes alone. Heterogeneity between studies was assessed by using I-squared statistics (I2). They used Meta-regression models to assess for mean age, duration of diabetes, mean follow-up, mean BMI, % female, and % white.
They included 9 prospective cohort studies with a total of 346,037 people who had diabetes and depression. The studies’ mean follow up period was 8.3 years, with a mean age of 60.4 years. Certain studies used self-reporting measures for depression and others used medical diagnosis. For studies that observed cardiovascular mortality, the pooled hazard ratio was 1.48 (95% CI: 1.185, 1.845), p=0.001 and heterogeneity of (I2= 43.4%). For studies that observed coronary heart disease, the pooled hazard ratio was 1.37 (95% CI: 1.165, 1.605), p<0.001 and heterogeneity of (I2= 15%). For studies that observed stroke, pooled hazard ratio was 1.33 (95% CI: 1.291, 1.369), p<0.001 and a heterogeneity of (I2= 84.7%). A study had found that over a 10 year follow up period, depression significantly accelerated the presentation of coronary heart disease (P<0.01), while another study did not find a significant difference. As a result, they found that there is a 47.9% increase in cardiovascular mortality, a 36.8% increase in coronary heart disease, and a 32.9% increase in stroke in people who have diabetes and depression. Regarding sensitivity analyses, a large discrepancy was found from assessing depression by self-reporting vs. clinical interview. Higher all-cause mortality risk was found with self-reports vs. a clinical interview.
This study provided an update of previous reviews and focused on the leading causes of morbidity and mortality in patients with type 2 diabetes in association with depression. They showed an increased risk of cardiovascular outcomes in patients who have both diabetes and depression. Therefore, it is crucial we that we provide appropriate management to patients who have diabetes with depression. Cardiovascular rehabilitation, exercise, and stress management may provide an improvement in depression and mortality associated with diabetes. Patients who have diabetes should be screened for psychological risk factors. Limitations of this analysis included a lack of assessment of baseline cardiovascular risk in those studies that it observed, making it less generalizable. Another limitation was the lack of assessment of confounding by antidepressant use. Antidepressants were found to be associated with cardiovascular outcomes. Lastly, the use of different assessments of depression (self-reporting vs. clinical interview) is another limitation to this analysis.
- Suffering from both diabetes mellitus and depression is significantly associated with the risk of cardiovascular mortality, coronary heart disease, and stroke.
- Cardiovascular disease prevention should be an integral part of treatment in this patient population.
- Assessment of the patient’s overall health including mental health is integral in treating the patient as a whole to prevent unfavorable outcomes.
Farooqi, A., et al. “Comorbid Depression and Risk of Cardiac Events and Cardiac Mortality in People with Diabetes: A Systematic Review and Meta-Analysis.” Diabetes Research and Clinical Practice, 2019
Nour Salhab, Pharm.D. Candidate, USF College of Pharmacy