The impact of COVID-19 on a college freshman sample reveals genetic and nongenetic forms of susceptibility and resilience to stress.

Using a longitudinal approach, we sought to define the interplay between genetic and nongenetic factors in shaping vulnerability or resilience to COVID-19 pandemic stress, as indexed by the emergence of symptoms of depression and/or anxiety. University of Michigan freshmen were characterized at baseline using multiple psychological instruments. Subjects were genotyped, and a polygenic risk score for depression (MDD-PRS) was calculated. Daily physical activity and sleep were captured. Subjects were sampled at multiple time points throughout the freshman year on clinical rating scales, including GAD-7 and PHQ-9 for anxiety and depression, respectively. Two cohorts (2019 to 2021) were compared to a pre-COVID-19 cohort to assess the impact of the pandemic. Across cohorts, 26 to 40% of freshmen developed symptoms of anxiety or depression (N = 331). Depression symptoms significantly increased in the pandemic years and became more chronic, especially in females. Physical activity was reduced, and sleep was increased by the pandemic, and this correlated with the emergence of mood symptoms. While low MDD-PRS predicted lower risk for depression during a typical freshman year, this genetic advantage vanished during the pandemic. Indeed, females with lower genetic risk accounted for the majority of the pandemic-induced rise in depression. We developed a model that explained approximately half of the variance in follow-up depression scores based on psychological trait and state characteristics at baseline and contributed to resilience in genetically vulnerable subjects. We discuss the concept of multiple types of resilience, and the interplay between genetic, sex, and psychological factors in shaping the affective response to different types of stressors.

Mineralocorticoid receptor function in major depression.

BACKGROUND: Negative feedback regulation of the hypothalamic-pituitary-adrenal axis occurs through a dual-receptor system of mineralocorticoid receptors (MR) and glucocorticoid receptors (GR). Their affinity for cortisol and their distribution in the brain differ. Studies using an MR antagonist have demonstrated that MR is active throughout the circadian rhythm. Because major depression is accompanied by increased glucocorticoid secretion and insensitivity to glucocorticoid feedback, and because glucocorticoids are capable of down-regulating MR and GR, we expected that major depression would be accompanied by decreased MR activity. METHODS: To test this hypothesis, we administered spironolactone, an MR antagonist, to individuals with major depression and matched control subjects and assessed levels of corticotropin and cortisol secretion in response to this acute challenge. Studies were conducted in the morning, the time of peak activation of the hypothalamic-pituitary-adrenal axis. All patients were currently depressed and free of all medications. All controls were free of all psychiatric diagnoses and of all medications. RESULTS: Spironolactone treatment resulted in a significant increase in cortisol secretion levels in both groups. Depressed patients demonstrated higher cortisol secretion levels than control subjects. In addition, depressed patients demonstrated a different pattern of increase in cortisol secretion levels after spironolactone administration. Furthermore, a significant effect of spironolactone treatment on corticotropin secretion levels can be observed in depressed patients, whereas controls show no such effect. CONCLUSIONS: Despite high baseline cortisol levels, patients with major depression show high functional activity of the MR system. Paired with the body of evidence regarding decreased sensitivity to GR agonists, these data suggest an imbalance in the MR/GR ratio. The balance of MR and GR is known to affect brain serotonin systems and may play an etiologic role in serotonin receptor changes observed in patients with major depression.