IGF-1 is elevated in patients with depression and non-remitters to antidepressant treatment

Abstract

Objective: We analyzed hormone levels in 86 patients with unipolar depression and 98 controls. Depressive patients were additionally divided into n = 43 patients with remission after 6 weeks and n = 43 patients without remission to antidepressive treatment. Both patients and controls as well as remitter and non-remitter were matched for age and gender. Design: An observational case-control study. Methods: Patients were elected from the Munich Antidepressive Response Signature (MARS) project [1]. Fasting laboratory parameters as cortisol, insulin like growth factor (IGF-1), testosterone, sex hormone binding globulin (SHBG), leptin, ghrelin and insulin were evaluated at admission to the Max-Planck-Institute of Psychiatry in Munich and after 6 weeks of treatment with antidepressants. Hamilton Depression Rating Scale score < 10 after 6 weeks was assumed as remission from depression. General linear model was used for statistical analyses. Age, gender and BMI were used as covariates in all analyses. Results: In patients with unipolar depression, IGF-1 levels (p = 0.001), cortisol levels (p = 0.002) and leptin levels (p = 0.0003) were elevated at admission compared to healthy controls. There was no statistical difference in testosterone, SHBG, ghrelin and insulin levels. Patients without remission to antidepressive treatment showed higher IGF-1 levels at admission (p = 0.018) than remitted patients. After 6 weeks, there was a non-significant trend for lower IGF-1 levels (p = 0.072) in remitters. There was no statistical difference for testosterone, SHBG, cortisol, leptin, ghrelin and insulin between remitted and non-remitted patients. Discussion: The influence of hormonal disturbances on mood is well known. Elevated IGF-1 levels were described in depressive patients. In our study, IGF-1 values differed in remitted patients and patients without remission to antidepressant treatment. IGF-1 levels might act as predictor for treatment response. Conclusion: Elevated IGF-1 values at admission were associated with depression and impaired response to antidepressive treatment in patients with unipolar depression.