Prevalence and epidemiological characteristics of chronic pain in the Spanish population. Results from the pain barometer.

Background: Chronic pain (CP) is a public health problem worldwide.

Aim: To update the prevalence of CP and compare the clinical and social characteristics of people with CP with those with non-chronic continuous pain and a group without pain.

Methods: An observational cross-sectional study was carried out in a representative sample of 7058 adults from the Spanish population. Sociodemographic data, the presence of CP and non-chronic continuous pain, characteristics of pain, limitations on activities of daily living (ADL), the presence and level of anxiety and depression (HADS), quality of life (SF-12v2) and social support (DUKE) were collected. Descriptive and bivariate analyses were performed.

Results: The prevalence of CP was 25.9% (95% CI;24.8-26.9) and that of non-chronic continuous pain was 7.7% (95% CI;7.1-8.3). Women presented a higher prevalence of both CP (30.5% vs. 21.3%) and non-chronic continuous pain (8.8% vs. 6.6%). CP was more common in the group between 55 and 75 years old (30.6%, 95% CI = 28.6-32.6%), non-chronic continuous pain affected most the population between 18 and 34 years old (11.2%, 95% CI = 9.6-12.7%). The median duration of CP was 4 years. The lumbar was the most frequent pain site (58.1%), and 27.1% did not know the cause. A greater frequency of limitations on ADL, more anxiety and depression, and worse quality of life were shown among the subjects with CP.

Conclusion: CP affects one in four Spanish people and impairs the mental, physical and social health. Differences exist by sex and age in its frequency. Identifying subjects with non-chronic continuous pain is fundamental to prevent their pain from becoming chronic.

Significance statement: Indicating the main aspects where this work adds significantly to existing knowledge in the field, and if appropriate to clinical practice. Due to its high prevalence and impact on quality of life, chronic pain has become one of the main health problems nowadays. Attention must be paid to it both from a clinical and social perspective, trying to raise awareness among the population of its possible causes and consequences. In routine clinical practice, greater consideration is given to groups of people with a higher prevalence of chronic pain, such as women and people with middle age, and with no chronic pain to prevent the appearance of chronic pain.