Medline ® Abstracts for References 1,2

BACKGROUND: Chronic pain is recognised as an important problem in the community but our understanding of the epidemiology of chronic pain remains limited. We undertook a study designed to quantify and describe the prevalence and distribution of chronic pain in the community.

METHODS: A random sample of 5036 patients, aged 25 and over, was drawn from 29 general practices in the Grampian region of the UK and surveyed by a postal self-completion questionnaire. The questionnaire included case-screening questions, a question on the cause of the pain, the chronic pain grade questionnaire, the level of expressed needs questionnaire, and sociodemographic questions.

FINDINGS: 3605 questionnaires were returned completed. 1817 (50.4%) of patients self reported chronic pain, equivalent to 46.5% of the general population. 576 reported back pain and 570 reported arthritis; these were the most common complaints and accounted for a third of all complaints. Backward stepwise logistic-regression modelling identified age, sex, housing tenure, and employment status as significant predictors of the presence of chronic pain in the community. 703 (48.7%) individuals with chronic pain had the least severe grade of pain, and 228 (15.8%) the most severe grade. Of those who reported chronic pain, 312 (17.2%) reported no expressed need, and 509 (28.0%) reported the highest expressed need.

INTERPRETATION: Chronic pain is a major problem in the community and certain groups within the population are more likely to have chronic pain. A detailed understanding of the epidemiology of chronic pain is essential for efficient management of chronic pain in primary care.

CONTEXT: There is little information on the extent of persistent pain across cultures. Even though pain is a common reason for seeking health care, information on the frequency and impacts of persistent pain among primary care patients is inadequate.

OBJECTIVE: To assess the prevalence and impact of persistent pain among primary care patients.

DESIGN AND SETTING: Survey data were collected from representative samples of primary care patients as part of the World Health Organization Collaborative Study of Psychological Problems in General Health Care, conducted in 15 centers in Asia, Africa, Europe, and the Americas.

PARTICIPANTS: Consecutive primary care attendees between the age of majority (typically 18 years) and 65 years were screened (n = 25 916) and stratified random samples interviewed (n = 5438).

MAIN OUTCOME MEASURES: Persistent pain, defined as pain present most of the time for a period of 6 months or more during the prior year, and psychological illness were assessed by the Composite International Diagnostic Interview. Disability was assessed by the Groningen Social Disability Schedule and by activity-limitation days in the prior month.

RESULTS: Across all 15 centers, 22% of primary care patients reported persistent pain, but there was wide variation in prevalence rates across centers (range, 5.5%-33.0%). Relative to patients without persistent pain, pain sufferers were more likely to have an anxiety or depressive disorder (adjusted odds ratio [OR], 4.14; 95% confidence interval [CI], 3.52-4.86), to experience significant activity limitations (adjusted OR, 1.63; 95% CI, 1.41 -1.89), and to have unfavorable health perceptions (adjusted OR, 1.26; 95% CI, 1.07-1.49). The relationship between psychological disorder and persistent pain was observed in every center, while the relationship between disability and persistent pain was inconsistent across centers.

CONCLUSIONS: Persistent pain was a commonly reported health problem among primary care patients and was consistently associated with psychological illness across centers. Large variation in frequency and the inconsistent relationship between persistent pain and disability across centers suggests caution in drawing conclusions about the role of culture in shaping responses to persistent pain when comparisons are based on patient samples drawn from a limited number of health care settings in each culture.