How sleep and depression are related: What does this contribute to interventions of sleep disorders and depression?

This literature review explores the complex relationship between sleep and depression. Sleep disturbances, particularly insomnia, are commonly observed in individuals with depression, with 60% to 90% of depressed patients experiencing these issues. Physiological factors, such as disruptions in the sleep-wake cycle, irregularities in cortisol and melatonin secretion, and activity of the hypothalamic-pituitary-adrenocortical (HPA) axis, along with imbalances in neurotransmitters like serotonin and dopamine, are key contributors to this relationship. Neuroimaging studies have identified that brain regions such as the anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), and amygdala are involved in both sleep regulation and depression, indicating shared neural pathways. Psychological factors, including stress, rumination, and anxiety, further intensify these problems. Effective treatments, such as antidepressants, cognitive behavioral therapy (CBT), and transcranial direct current stimulation (tDCS), show potential in addressing both sleep disorders and depression concurrently. However, challenges remain, including small sample sizes, reliance on self-reported data, and a lack of long-term follow-up, highlighting the need for further research. Future studies should investigate integrated treatment approaches to more effectively address the co-occurrence of sleep disorders and depression.