Sleep disorders in patients with chronic pain: cross-sectional study

ABSTRACT

BACKGROUND AND OBJECTIVES:

Chronic pain and its relationship with sleep disturbance are common conditions with great influence on the individual’s quality of life. The simultaneous occurrence of these two entities results in greater suffering, reduced functionality and well-being. The objective of this research was to evaluate the influence of chronic pain on sleep and its impact on quality of life.

METHODS:

This is an observational, cross-sectional, individual, uncontrolled study carried out at the Multidisciplinary Pain Center of the Clinical Hospital of the Federal University of Minas Gerais (Hospital das Clínicas da Universidade Federal de Minas Gerais - HC-UFMG). The patients answered a semi-structured, face-to-face interview via the pain center’s own computer system (avaliaDor®), using internet-connected mobile devices. Socioeconomic and pain data was collected, and then instruments were applied to assess pain intensity (Visual Numerical Scale - VNS), quality of life (Medical Outcomes Study 36 - Short Form Health Survey - SF-36), presence of psychiatric disturbances (Hospital Depression Anxiety Scale - HAD) and sleep (Mini Sleep Questionnaire - MSQ).

RESULTS:

One hundred and three patients participated in the study. Seventy two percent were women, the median age was 55 years, and the patients were predominantly married, white and with a low level of schooling. Of the entire study population 74.76% presented “severe difficulty” in sleeping, while 22.33% had “good quality” sleep. Regarding pain intensity, patients in the moderate and severe pain groups had a higher percentage of “severe difficulty” in sleeping, when compared to patients with mild pain. About the presence of anxiety and depression, it was observed lower scores on: “restless sleep”, “tiredness for no apparent reason”, “wakes up with a headache”, “wakes up and goes back to sleep”, “wakes up tired in the morning”, and finally “wakes up and does not go back to sleep”. The general data from the SF-36 points to a low quality of life for the patients in the present study and, based on the multivariate analysis, the items “SF-36-Pain and SF-36-Vitalidade” were shown to be protective factors for the presence of sleep disturbances.

CONCLUSION:

Sleep disorders in patients with chronic pain are common and show a worsening in quality of life. The frequency of this disturbance was higher in patients with anxiety and depression compared to patients without these psychiatric disorders. The early identification of sleep disturbances in individuals with chronic pain is necessary to improve well-being.

Keywords:
Chronic pain; Quality of life; Sleep

HIGHLIGHTS

This article analyzed chronic pain and sleep disorders, two relevant topics due to their high prevalence and influence on quality of life.

This research linked sleep disorders with mood and anxiety disorders, common psychiatric comorbidities in chronic pain patients.

The importance of assessing patients with chronic pain for the presence and severity of sleep disorders was demonstrated, with the aim of adapting multidimensional pain treatment.