Aim: This study was aimed to determine the relationship between sleep quality and mental health of veterans in comparison with that of their spouses and a control group. Methods: Thirty-seven chemical veterans with moderate to severe injury based on the standards of Foundation of Martyrs and Veterans Affairs were selected from Mazandaran province. Then, the spouses of 31 of them were selected and 15 of their close relatives also enrolled in the study as the control group. The three groups were evaluated by GHQ for their mental health and Pittsburg Sleep Quality Index (PSQI) for sleep quality. Collected data were analyzed using SPSS software 16 and descriptive and analytic statistical methods. Results: The mean score of mental health in veterans, their spouses and close relatives were 44.13 ± 14.4, 34.19 ± 15.2 and 21.73 ± 17.32, respectively. The mean scores of PSQI test in veterans, their spouses, and their close relatives were 10.94 ± 5.6, 8.7 ± 5.5 and 4.27 ± 1 that the difference was statistically significant among the three groups (P ≤ 0.0001). A positive relationship was seen between mental health and sleep quality in veterans and their spouses respectively (r = 0.4, P = 0.02) and (r = 0.83, P < 0.0001). Conclusion: Poor sleep quality in chemical veterans compared to their spouses and close relatives could be due to mental health, rather than chemical effects and chronic lung disease. Therefore, treatment of mental health might be an important step to improve the sleep quality of veterans.
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