Risk factors for incident shoulder soft tissue rheumatic disorders: a population-based case-control study in Lebanon

Soft tissue rheumatic disorders (STRDs) are very common and impact enormously general population, working groups and physiotherapist practices. However, they do not have neither a clear case definition nor objective tests to be accurately diagnosed rendering them neglected with poorly-estimated burden. Shoulder is one of the most frequent sites for STRDs.

The aim of this study was to identify risk factors for shoulder STRDs among Lebanese adults aged ≥ 15 years.

A case-control study was designed based on data from the Community Oriented Program for Control of Rheumatic Diseases (COPCORD) study conducted in Lebanon in 2009. Cases were defined as those who recently suffered from shoulder pain, tenderness or stiffness with duration not exceeding 12 months (52 cases). These were frequency-matched by age and gender with 208 controls who never experienced any musculoskeletal pain.

Area of residence, physical activity, family history and stress-induced sleep difficulty were significantly associated with shoulder STRDs after adjusting for cigarette smoking, job nature and family monthly income.

Factors associated with shoulder STRD among the Lebanese population include geographical location, psychosocial factors, physical activity and familial predisposition. Further longitudinal studies are needed to establish a temporal sequence and explore other potential determinants, especially among the working population.