The Interaction of Oxytocin and Social Support, Loneliness, and Cortisol Level in Major Depression

OBJECTIVE: Loneliness is a specific risk factor for depressive symptoms and suicidal behavior. The present study examined whether the serum oxytocin level would interact with social support and buffers loneliness and hypothalamic-pituitary-adrenal (HPA)-axis activity in drug-naïve patients with major depressive disorder (MDD). METHODS: Twenty-six patients with MDD (male:female = 3:23; mean age, 45.54 ± 12.97 years) were recruited. The 17-item Hamilton Depression Rating Scale, UCLA Loneliness Scale and self-reported Measurement of Support Function Questionnaire were administered. Serum oxytocin and cortisol levels were assessed using a commercial immunoassay kits. RESULTS: In MDD patients, a negative association was found between degrees of social support and loneliness (β = −0.39, p = 0.04). The interaction between social support and serum oxytocin level was negatively associated with loneliness (β = −0.50, p = 0.017) and serum cortisol level (β = −0.55, p = 0.020) after adjusting for age. Follow-up analyses showed that the association between higher social support and lower loneliness was observed only in the higher-oxytocin group (r = −0.75, p = 0.003) but not in the lower group (r = −0.19, p = 0.53). The significance remained after further adjusting for sex and depression severity. CONCLUSION: Low oxytocin level is a vulnerability factor for the buffering effect of social support for loneliness and aberrant HPA-axis activity in MDD patients.

Prognosis of patients on extracorporeal membrane oxygenation plus continuous arteriovenous hemofiltration.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has been utilized for critically ill patients such as those with life-threatening respiratory failure or post-cardiotomy cardiogenic shock. Patients on ECMO with acute renal failure have high mortality rates. This study identifies specific predictors of hospital mortality for patients receiving ECMO and continuous arteriovenous hemofiltration (CAVH). METHODS: This study reviewed the medical records of 123 critically ill patients on ECMO plus CAVH at a cardiovascular surgical intensive care unit (CVSICU) at a tertiary care university hospital between March 2003 and August 2010. Patient baseline, clinical, and laboratory data were collected retrospectively as survival predicators. RESULTS: The overall mortality rate was 85.4%. The most common conditions requiring ECMO plus CAVH were cardiogenic shock and oliguria. The Acute Physiology and Chronic Health Evaluation II (APACHE II) score and organ system failure (OSF) score both indicated good discriminative power (area under the receiver operating characteristic curve [AUROC] 0.812 ± 0.048 and 0.758 ± 0.057, respectively). Multiple logistic regression analysis indicated that age, mean arterial pressure, and OSF score on day 1 of ECMO plus CAVH were independent risk factors for hospital mortality. Cumulative survival rates at the 6-month follow-up differed significantly (p < 0.001) between those with an OSF score ≤ 4 vs. those with an OSF score > 4. CONCLUSIONS: During ECMO plus CAVH support, both the OSF and APACHE II scores showed good discriminative power in predicting hospital mortality for these patients.