Sleep disturbances in patients with comorbid coronary heart disease and depression

Aim. To study the presence and severity of insomnia in patients with comorbid coronary heart disease (CHD) and depressive disorder (DD). Materials and methods. The study included 132 patients with CHD (class II–III exertional angina after myocardial infarction experienced more than 6 months ago): 58 patients with DD and 74 patients without depression. The Beck Depression Inventory (BDI) was used to diagnose DD. The diagnosis in all cases was confirmed by a therapist. Sleep disturbances were assessed using the Sheehan Patient-Rated Anxiety Scale (ShAS). The data were presented as M ± SD; n (%); and Me [25%; 75%]. The differences were considered significant at p < 0.05. Results. Insomnia in the general group of patients was registered as follows: none or clinically not significant – in 62 patients (54.9%), clinically significant – in 51 patients (45.1%). Night awakenings in the general group of patients were detected as follows: none or clinically not significant – in 66 patients (58.4%), clinically significant – in 47 patients (41.6%). Disturbances in falling asleep and night awakenings were significantly pronounced in patients with CHD with identified DD compared to patients without mental disorders: disturbances in falling asleep – 2 [1; 3] vs. 1 [0; 2] (p = 0.0001), night awakenings – 2 [1; 3] vs. 1 [0; 2] (p = 0.00002), respectively. In the group of CHD with DD (n = 58), 2 people (3.4%) did not complete the scale. Among those who did, 12 patients (21.4%) had no difficulty falling asleep, 9 patients (16.1%) had little difficulty, and 35 patients (62.5%) had clinically significant disturbances. In the group of CHD without DD (n = 74), 17 people (23%) did not complete the scale. Among those who did (n = 57), 21 patients (36.8%) had no difficulty falling asleep, 20 patients (35.1%) had little difficulty, and 16 patients (28.1%) had clinically significant problems. In patients with comorbid CHD and DD who completed the ShARS (n = 56), 7 patients (12.5%) had no night awakenings, 17 patients (30.4%) had few night awakenings, and 32 patients (57.1%) had clinically significant disturbances in maintaining sleep. In the group without DD, among those who completed the ShARS (n = 57), 18 patients (31.6%) had no night awakenings, 24 patients (42.1%) had few night awakenings, and 15 patients (26.4%) had clinically significant disturbances in maintaining sleep. Significant differences were noted for all test questions (p < 0.0005). Conclusion. In patients with comorbid CHD and DD, changes in the circadian rhythm are detected in the form of significant disturbances in falling asleep and awakening, which can aggravate the clinical course of CHD and the prognosis of patients with cardiovascular diseases.