Clinical Depression, Antidepressant Use, and Metabolic Syndrome-related Comorbidities among Canadian Older Adults: A Cross-sectional Analysis of Baseline Data from the Canadian Longitudinal Study of Aging
Background: Clinical depression is associated with a number of biological alterations and behaviours that can increase the risk of metabolic syndrome (MetS). Antidepressant medications (AD) are frequently used to treat depressed patients, but it often has side effects such as metabolic abnormalities. MetS is a well-known risk factor for multiple chronic diseases including cancer, and cardiovascular disease (CVD). However, it is unclear how clinical depression, AD use, and MetS are associated with cancer and CVD. Objective: To explore the relationship between clinical depression, AD use, and MetS-related chronic disorders, with a specific focus on cancer and CVD, and to assess how associations differ by MetS status, among Canadian older adults. Methods: The baseline data of the Canadian Longitudinal Study on Aging Comprehensive Cohort of 29,366 men and women aged 45 years and older was used in the analysis. Clinical depression was defined by self-reported clinical diagnosis of depression. Current depression treatment type was categorized into three groups: AD use only, other types of depression therapy, and no current depression therapy. MetS was defined by the harmonized criteria developed by the International Diabetes Federation, and American Health Association/National Heart, Lung, and Blood Institute. Logistic regression was used to estimate the associations of cancer or CVD on the basis of distribution of depression, current treatment types, and MetS. Results: The overall prevalence of clinical depression was 17.3%, and AD use was 8.1%. Compared to non-depressed individuals, depressed individuals taking AD had higher odds of colorectal cancer, and lung cancer. Depressed individuals using AD had higher odds of CVD, except peripheral vascular disease. Regardless of depression status, MetS showed no association with cancers. Among non-depressed individuals, MetS was associated with CVD compared to those without MetS. Within depressed individuals using AD, MetS did not appear to be associated with CVD. Conclusion: Clinical depression and AD use are associated with colorectal cancer, but the association may be independent of MetS. The positive associations between clinical depression, AD, and lung cancer or CVD were mitigated by comorbidity. MetS did not appear to play a role in the association between clinical depression, AD, and MetS-related chronic diseases.