Objective short sleep duration is associated with elevated blood pressure in depression: The autonomic nerve dysfunction effect

The relationship between sleep disturbance, autonomic nerve dysfunction, and blood pressure in patients with major depressive disorder (MDD) was unclear. We studied 66 patients with MDD and 66 age‐matched and sex‐matched controls. Objective and subjective sleep were assessed using the polysomnography and Pittsburgh Sleep Quality Index, respectively. Autonomic nerve function was assessed using the heart rate variability (HRV). The averaged evening and morning systolic (SBP) and diastolic blood pressure (DBP) were analyzed. In patients with MDD, each 1 h reduction in an objective sleep duration was associated with 2.56‐mmHg increase in SBP ( p = 0.011) and 1.59‐mmHg increase in DBP ( p = 0.043). Increase in NREM‐heart rate (HR), NREM‐low frequency normalized unit (LFnu), and REM‐HR and decrease in NREM‐standard deviation of NN intervals, NREM‐root mean square of successive differences, and NREM‐LFnu were associated with shorter objective sleep duration (all p ≤ 0.043) and higher SBP and DBP (all p ≤ 0.037). These HRV mediated the association between objective sleep duration and BP with 17–79% mediating effects. No association was observed between subjective sleep duration and BP in patients with MDD or between objective/subjective sleep duration and BP in controls. In conclusion, objective, but not subjective short sleep duration, is associated with increased blood pressure in patents with MDD, that is mediated by autonomic nerve dysfunction.