Lower Extremity Tendinopathies are Associated with Metabolic and Chronic Diseases: A Systematic Review

Background. Recent narrative reviews suggest an association between lower extremity tendinopathies and metabolic and chronic diseases. This association might lead to early recognition and change in clinical management, but it has, however, never been assessed systematically. Objective. To analyze the association between lower extremity tendinopathies and metabolic and chronic diseases in a systematic review. We searched studies in Embase, Medline Ovid, Web of Science, Cochrane library and Google Scholar. Articles were eligible if the association between clinically diagnosed lower extremity tendinopathies and a metabolic or chronic disease in adult patients was reported. Results. From 4,287 eligible studies, we included 10 cohort studies and 10 case-con-trol studies, involving 83,948 participants. Almost all (90%) included studies were assessed as having a high risk of bias. These studies had moderate evidence for an association between lower extremity tendinopathies and obesity, ankylosing spondylitis, psoriatic arthritis, and reactive arthritis. There was limited evidence for an association between lower extremity tendinopathies and heterozygous familial hypercholesterol-emia, and Systemic Lupus Erythematosus. Conclusions. We found multiple associations between lower extremity tendinopathies and metabolic and chronic diseases. These results suggest that medical professionals should screen for these specific metabolic and chronic diseases in patients with lower extremity tendinopathies. Study registration. The review has been prospectively registered in the international PROSPERO database. Protocol details were submitted in June 2019 and registered in September 2019 (registration number: CRD42019140317).