RESUMO
OBJECTIVE: Sleep is a vital function for human beings, which can be affected by several factors. Chronic pain is one of these factors where it is the most frequent cause for seeking medical care in combination with insomnia. The aim of this study is to examine the prevalence and relationship between sleep disturbance and chronic pain. PATIENTS AND METHODS: After approval, a total of 85 Family Medicine Units from over 170 in Tokat were randomly selected using a 50% sampling. A sample of 2635 subjects, over the age of 19 years, who were registered with the selected Family Medicine Units, were assessed due to gender, age group, and the urban/rural population size of Tokat using the stratified sampling method. The sample size distribution was calculated as 1515 urban subjects, 1120 rural subjects; 1345 female subjects, 1290 male subjects; 1123 subjects between 20-39 years of age, 1103 subjects between the ages of 40-64, and 409 subjects over 64 years of age. After sampling, subjects were invited to participate in the study via an invitation letter, and agreeing individuals were taken to the Family Medicine Unit for face-to-face meetings. Written, informed consent was obtained, along with demographic data. The presence of chronic pain was recorded. According to the presence of chronic pain, all subjects were separated into two groups as Group Chronic Pain and Group Non-Chronic Pain. The visual analog scale for pain intensity, and Pittsburgh Sleep Quality Index for sleep quality, were performed with all subjects. A multiple linear regression model was used to assess the predictors of sleep quality. Analyses were conducted using the Statistical Package for Social Sciences program (SPSS Inc., Chicago, IL, USA), version 20.0. The statistical significance for all analyses was set at p < 0.05. RESULTS: The mean global Pittsburgh Sleep Quality Index score of Group Chronic Pain (5.30 ± 4.29) was significantly higher than in Group Non-Chronic Pain (3.22 ± 3.30; p < 0.01). The mean Pittsburgh Sleep Quality Index scores of females (5.69 ± 4.40) were significantly higher than males (4.54 ± 3.96) in Group Chronic Pain (p = 0.000045). A total of 40.7% of patients in Group Chronic Pain, and 21.9% in Group Non-Chronic Pain demonstrated poorer sleep quality according to the Pittsburgh Sleep Quality Index scores, with a cut-off level > 5. A moderate positive correlation was found between the global Pittsburgh Sleep Quality Index and Visual Analog Scale scores (r = 0.310, p < 0.01). A multiple linear regression analysis showed that age, gender, income, Visual Analog Scale, and presence of depression were the significant predictors for Pittsburgh Sleep Quality Index score. CONCLUSIONS: The current study revealed that chronic pain and pain intensity are important predictors of sleep quality.
