Metabolic syndrome does not accurately predict chronicity or severity in older adults with a formal diagnosis of depression, according to study results published in the Journal of Affective Disorders.
Investigators pooled data from older adults, aged ≥ 60 years, with (n=378) and without (n=132) a depressive disorder from the Netherlands Study of Depression in Old Age (NESDO). At baseline and at two- and six-year follow-up, investigators assessed depression and metabolic syndrome using written questionnaires, face-to-face interviews, physical examinations, and blood tests. Patients received postal questionnaires every six months during the study period.
Cox regression analysis showed that depressed patients with metabolic syndrome did not differ from depressed patients without metabolic syndrome in time to remission (hazard ratio, 1.03; 95% CI, 0.74-1.44; P =.85). In addition, individual metabolic syndrome components or the number of metabolic syndrome components was not associated with time to remission. Remission was defined as the absence of a six-month diagnosis of depression at two- or six-year follow-up. Using linear mixed models, investigators found that metabolic syndrome was also not associated with depression severity (B=0.02; standard error=0.04; P =.64) or course of depressive symptoms (B=−0.01; standard error= 0.01; P =.23).
The study was limited by a high attrition rate (46.8%) and a lack of information about total duration and course of both metabolic syndrome and depression at baseline.
Investigators noted, “It is possible that pathophysiological processes inherent to ageing conceal underlying associations between biomarkers and depression. Large, long-term cohort studies that follow vulnerable persons through different life stages may provide a better opportunity to disentangle the complex [etiology] of late-life depression.”
Dekker IP, Marijnissen RM, Giltay EJ, et al. The role of metabolic syndrome in late-life depression over 6 years: the NESDO study. J Affect Disord. 2019;257:735-740.