The Relationship of Aging and Smoking with Rotator Cuff Disease: A Systematic Review and Meta-Analysis.

OBJECTIVE: Despite rotator cuff disease being one of the most common causes of shoulder pain, its pathogenesis and biology are poorly understood. In this study, we synthesized evidence from studies reporting associations for aging and smoking status in relation to rotator cuff disease. DESIGN: A systematic review was performed using multiple databases (PubMed, Embase, Cochrane, CINAHL, and Science Direct). Articles that met our eligibility criteria and presented data on the association between aging and/or smoking status and rotator cuff disease were included. We performed meta-analyses and report cumulative effects using odds ratios (OR) and corresponding 95% confidence intervals (CI). RESULTS: Of the 212 articles eligible for full-text review, seven studies reported on the relationship between aging and rotator cuff disease and ten studies reported on the relationship between smoking and rotator cuff disease. Aging was consistently associated with increased odds of having rotator cuff disease when assessed continuously (per 10-year increase: OR = 1.20, 95% CI: 1.18, 1.21) or categorically [<40 years old versus: (a) 40-44 years old (OR = 2.71, 95% CI: 1.78, 4.13), (b) 45-49 years old (OR = 4.33, 95% CI: 2.88, 6.55), and (c) 50 years of age or older (OR = 6.97, 95% CI: 4.85, 10.01)]. Assessing studies that reported smoking status as current smokers versus non-smokers, current smokers were more likely to have rotator cuff disease (OR = 1.94, 95% CI: 1.52, 2.48). However, a statistically significant association was not found when never smokers were compared to former smokers (OR = 1.08, 95% CI: 0.97, 1.20) and to current smokers (OR = 0.97, 95% CI: 0.87, 1.07). CONCLUSION: In this systematic review and meta-analysis, increasing age was a strong risk factor for rotator cuff disease. The finding that current smokers are more likely to have rotator cuff disease as compared with non-smokers implies that cessation of smoking can potentially lead to mitigation of this risk factor.