Neuroimmune mechanisms of depression in heart failure

Depressive symptoms in asymptomatic stage B heart failure with Type II diabetic mellitus

BACKGROUND

The presence of concomitant Type II diabetic mellitus (T2DM) and depressive symptoms adversely affects individuals with symptomatic heart failure (HF).

HYPOTHESIS

In presymptomatic stage B HF, this study hypothesized the presence of greater inflammation and depressive symptoms in T2DM as compared to non-T2DM Stage B patients.

METHODS

This cross-sectional study examined clinical parameters, inflammatory biomarkers, and depressive symptoms in 349 T2DM and non-T2DM men with asymptomatic stage B HF (mean age 66.4 years ±10.1; range 30-91).

RESULTS

Fewer diabetic HF patients had left ventricular (LV) systolic dysfunction (P < .05) although more had LV diastolic dysfunction (P < .001). A higher percentage of T2DM HF patients were taking ACE-inhibitors, beta-blockers, calcium channel blockers, statins, and diuretics (P values < .05). T2DM HF patients had higher circulating levels of interleukin-6 (IL-6) (P < .01), tumor necrosis factor-alpha (P < .01), and soluble ST2 (sST2) (P < .01) and reported more somatic/affective depressive symptoms (Beck Depression Inventory II) (P < .05) but not cognitive/affective depressive symptoms (P = .20). Among all patients, in a multiple regression analysis predicting presence of somatic/affective depressive symptoms, sST2 (P = .026), IL-6 (P = .010), B-type natriuretic peptide (P = .016), and sleep (Pittsburgh Sleep Quality Index [P < .001]) were significant predictors (overall model F = 15.39, P < .001, adjusted R2 = .207).

CONCLUSIONS

Somatic/affective but not cognitive/affective depressive symptoms are elevated in asymptomatic HF patients with T2DM patients. Linkages with elevated inflammatory and cardiac relevant biomarkers suggest shared pathophysiological mechanisms among T2DM HF patients with somatic depression, and these conditions are responsive to routine interventions, including behavioral. Copyright © 2019 John Wiley & Sons, Ltd.

The Role of Gratitude in Spiritual Well-being in Asymptomatic Heart Failure Patients

Spirituality and gratitude are associated with wellbeing. Few if any studies have examined the role of gratitude in heart failure (HF) patients or whether it is a mechanism through which spirituality may exert its beneficial effects on physical and mental health in this clinical population. This study examined associations bet ween gratitude, spiritual wellbeing, sleep, mood, fatigue, cardiac-specific self-efficacy, and inflammation in 186 men and women with Stage B asymptomatic HF (age 66.5 years ±10). In correlational analysis, gratitude was associated with better sleep (r=-.25, p<0.01), less depressed mood (r=-.41, p<0.01), less fatigue (r=-.46, p<0.01), and better self-efficacy to maintain cardiac function (r=.42, p<0.01). Patients expressing more gratitude also had lower levels of inflammatory biomarkers (r=-.17, p<0.05). We further explored relationships among these variables by examining a putative pathway to determine whether spirituality exerts its beneficial effects through gratitude. We found that gratitude fully mediated the relationship between spiritual wellbeing and sleep quality (z=-2.35, SE=.03, p=.02) and also the relationship between spiritual wellbeing and depressed mood (z=-4.00, SE=.075, p<.001). Gratitude also partially mediated the relationships between spiritual wellbeing and fatigue (z=-3.85, SE=.18, p<.001), and between spiritual wellbeing and self-efficacy (z=2.91, SE=.04, p=.003). In sum, we report that gratitude and spiritual wellbeing are related to better mood and sleep, less fatigue, and more self-efficacy, and that gratitude fully or partially mediates the beneficial effects of spiritual wellbeing on these endpoints. Efforts to increase gratitude may be a treatment for improving wellbeing in HF patients' lives and be of potential clinical value.

Depressive symptoms and spiritual wellbeing in asymptomatic heart failure patients

Depression adversely predicts prognosis in individuals with symptomatic heart failure. In some clinical populations, spiritual wellness is considered to be a protective factor against depressive symptoms. This study examined associations among depressive symptoms, spiritual wellbeing, sleep, fatigue, functional capacity, and inflammatory biomarkers in 132 men and women with asymptomatic stage B heart failure (age 66.5 years ± 10.5). Approximately 32 % of the patients scored ≥10 on the Beck Depression Inventory, indicating potentially clinically relevant depressive symptoms. Multiple regression analysis predicting fewer depressive symptoms included the following significant variables: a lower inflammatory score comprised of disease-relevant biomarkers (p < 0.02), less fatigue (p < 0.001), better sleep (p < 0.04), and more spiritual wellbeing (p < 0.01) (overall model F = 26.6, p < 0.001, adjusted R square = 0.629). Further analyses indicated that the meaning (p < 0.01) and peace (p < 0.01) subscales, but not the faith (p = 0.332) subscale, of spiritual wellbeing were independently associated with fewer depressive symptoms. Interventions aimed at increasing spiritual wellbeing in patients lives, and specifically meaning and peace, may be a potential treatment target for depressive symptoms asymptomatic heart failure.

Depression and cardiac disease: epidemiology, mechanisms, and diagnosis

In patients with cardiovascular disease (CVD), depression is common, persistent, and associated with worse health-related quality of life, recurrent cardiac events, and mortality. Both physiological and behavioral factors—including endothelial dysfunction, platelet abnormalities, inflammation, autonomic nervous system dysfunction, and reduced engagement in health-promoting activities—may link depression with adverse cardiac outcomes. Because of the potential impact of depression on quality of life and cardiac outcomes, the American Heart Association has recommended routine depression screening of all cardiac patients with the 2- and 9-item Patient Health Questionnaires. However, despite the availability of these easy-to-use screening tools and effective treatments, depression is underrecognized and undertreated in patients with CVD. In this paper, we review the literature on epidemiology, phenomenology, comorbid conditions, and risk factors for depression in cardiac disease. We outline the associations between depression and cardiac outcomes, as well as the mechanisms that may mediate these links. Finally, we discuss the evidence for and against routine depression screening in patients with CVD and make specific recommendations for when and how to assess for depression in this high-risk population.