Chronic physical diseases and depressive symptoms : insight into the association of long QT syndrome and type 2 diabetes with depressive symptoms
Year: 2018
Type: dissertation
Study design: Observational Study
Abstract: Individuals diagnosed with chronic physical diseases, such as coronary artery disease (i.e., a cardiac condition being a risk factor for ventricular arrhythmias) and type 2 diabetes (T2D; i.e., a metabolic condition characterized by high glucose levels), are at risk of developing mental health problems. In parallel, people with mental health problems, including depressive symptoms, have an increased risk of being diagnosed with a chronic physical disease. The co-occurrence of physical and mental conditions is a major public health concern, since it can significantly decrease quality of life, contribute to worse health outcomes and a higher rate of mortality, and bring enormous economic costs to society. Thus, identifying the concomitance of physical and mental health problems as well as understanding its underlying mechanisms are primary steps in developing strategies to prevent and treat the incidence of comorbid conditions. The main aim of this study was to examine: 1) whether long QT syndrome (LQTS; i.e., a genetic heart condition which can predispose to ventricular arrhythmias) mutation carrier status is associated with the risk of depressive symptoms (Study I); 2) whether depressive symptoms are associated with the risk of arrhythmic events in women and men with LQTS (Study I); 3) whether depressive symptoms predict glucose levels, or vice versa, in women and men (Study II); 4) whether changes in body fat, inflammation, alcohol consumption, or tobacco or cigarette smoking are likely to mediate these possible associations (Study II); and 5) whether elevated glucose is likely to be a causal risk factor for depressive symptoms (Study III). In Study I, the participants were derived from the Finnish LQTS registry (the 2011 follow-up). The sample consisted of 782 participants. There were 369 genetically defined LQTS mutation carriers (169 with and 200 without arrhythmic events). The control group comprised 413 relatives without a familial LQTS mutation. Depressive symptoms were assessed using the Beck Depression Inventory-II. The participants in Study II (n = 2534; data from the 2001, 2007, and 2012 follow-ups) and Study III (n = 1217; data from 2012) were from the Cardiovascular Risk in Young Finns Study, a Finnish prospective, population-based study. Depressive symptoms were assessed with a modified Beck Depression Inventory. Blood glucose levels were based on the single measurement of fasting serum glucose concentrations. The results of Study I revealed that LQTS mutation carrier status was not associated with the risk of depressive symptoms. Depressive symptoms were, however, associated with an increased risk of arrhythmic events in men but not in women with LQTS. Furthermore, Study II showed that depressive symptoms in 2001 were positively associated with glucose in 2012 in women but not in men. This sex difference was significant. Glucose in 2001 did not predict depressive symptoms in 2012 in either sex. Moreover, changes (from 2001 to 2007) in body fat, inflammation, alcohol consumption, or tobacco or cigarette smoking did not mediate the observed association in women. In Study III, glucose was not associated with depressive symptoms in the standard linear regression, but the instrumental-variable regression showed a negative association between glucose and depressive symptoms. The difference between the estimates derived from these two regression models was significant. The findings suggest that depressive symptoms can be a risk factor for arrhythmic events in men but not in women with LQTS. Further, the results indicate that women with depressive symptoms but not men may have elevated glucose concentrations, and thus may be at increased risk for the development of T2D. The mechanisms underlying this association, however, still remain unclear. Moreover, elevated glucose is unlikely to be a causal risk factor for depressive symptoms. Therefore, the association from T2D to depressive symptoms might not be due to chronically elevated glucose. It is, however, possible that this relationship may result from low glucose concentrations. Given these findings, prevention and treatment of depressive symptoms might be beneficial for prevention of arrhythmic events in men with LQTS and blood glucose abnormalities among women in the general population.
Source: Työväentutkimus Vuosikirja
Author: Karolina Wesołowska
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2906233604