Objective  To study the correlation between sleep quality and mental health among lonely elderly people in Tibet Autonomous Region (Tibet) and to provide evidences for improving sleep quality and mental health of the elderly.

  Methods  We conducted a questionnaire survey among 275 lonely elderly people selected with random cluster sampling in 6 five-guarantee centralized support service centers in Lhasa, Shannan, Shigatse, and Nyingchi of Tibet from September to November 2018. Pittsburgh Sleep Quality Index (PSQI) was adopted to assess the participants' sleep quality and a mental health scale for urban elderly Chinese was used in the survey.

  Results  Of all the participants, 40.0% (110), 34.5% (95) and 25.5% (70) were assessed as having a good, normal, and poor sleep quality. The mean overall PSQI score of the participants was 5.71 ± 3.57 and the domain scores were 0.86 ± 0.80 for subjective sleep quality, 0.98 ± 1.04 for sleep latency, 0.39 ± 0.71 for sleep duration, 0.51 ± 0.88 for habitual sleep efficiency, 1.30 ± 0.55 for sleep disturbance, 0.61 ± 1.08 for sleeping medication, and 1.07 ± 0.93 for daytime dysfunction, respectively. The mean total mental health score of the participants was 187.988 ± 17.493 and the participants' scores of five mental health dimensions were 56.071 ± 6.894 for adaptability, 7.148 ± 5.155 for interpersonal communication, 33.762 ± 4.462 for self-awareness, 46.441 ± 5.227 for emotional experience, and 25.566 ± 4.327 for cognitive performance. Correlation analyses demonstrated that the overall PSQI score was inversely correlated with the total mental health score and its five dimension scores (P < 0.05 for all).

  Conclusion  Poor sleep quality is prevalent and exerts obvious impacts on mental health status among lonely elderly people in Tibet. The improvement in sleep quality may promote mental health in the population.