Sleep patterns and symptoms of anxiety and depression in patients with chronic pain.

BACKGROUND Sleep disturbances and symptoms of anxiety and depression have been shown to be involved in the genesis and perpetuation of chronic pain. OBJECTIVE To evaluate sleep patterns and the prevalence of symptoms of anxiety and depression in patients with chronic pain. METHOD Four hundred consecutive patients referred to a chronic pain outpatient clinic were investigated using patient charts, the numerical Visual Analogue Scale for the evaluation of pain, the Hospital Anxiety and Depression scale and the Mini-Sleep Questionnaire. RESULTS The mean age of patients was 45.6+/-11.4 years. The most frequent medical diagnosis was myofascial pain followed by neuropathic pain. The prevalence of symptoms of anxiety was 72.8%, depression 93% and altered sleep patterns 93%. CONCLUSION This study revealed a high prevalence of symptoms of depression and anxiety and alterations in sleep patterns in patients with chronic pain, justifying investigation into these disturbances in this group of patients.