Prevalence of symptomatic axial osteoarthritis phenotypes in Spain and associated socio-demographic, anthropometric, and lifestyle variables

Objective Axial osteoarthritis (OA) is a common cause of back and neck pain, however, few studies have examined its prevalence. The aim was to estimate the prevalence and the characteristics of symptomatic axial OA in Spain. Methods EPISER2016 is a cross-sectional multicenter population-based study of people aged 40 years or older. Subjects were randomly selected using multistage stratified cluster sampling. Participants were contacted by telephone to complete rheumatic disease screening questionnaires. Two phenotypes were analyzed, patients with Non-exclusive axial OA (NEA-OA) and Exclusive axial OA (EA-OA). To calculate the prevalence and its 95% confidence interval (CI), the sample design was considered and weighting was calculated according to age, sex and geographic origin. Results Prevalence of NEA-OA by clinical or clinical-radiographic criteria was 19.17% (95% CI: 17.82-20.59). The frequency of NEA-OA increased with age (being 3.6 times more likely in patients aged 80 s or more than in those between 40 and 49 years) and body mass index. It was significantly more frequent in women, as well as in the center of Spain. It was less frequent in those with a higher level of education. Lumbar OA was more frequent than cervical OA. This difference grew with increasing age and was not associated with gender. It was also greater in overweight and obese subjects. Conclusions This is the first study on the prevalence of axial OA phenotypes in Europe describing the associated socio-demographic, anthropometric, and lifestyle variables.

Automated summary

This study estimated the prevalence of symptomatic axial osteoarthritis in Spain to be 19.17%, with higher rates in older individuals and those with higher body mass index. It was more common in women and in the central region of Spain, and less prevalent in those with higher education levels. Lumbar OA was more frequent than cervical OA and was associated with age and weight status.