Risk factors for rotator cuff disease: A systematic review and meta-analysis of diabetes, hypertension, and hyperlipidemia.

Studies did not define rotator cuff disease the same way, so the pooled result mixes tears, tendinopathy, tendonitis and rotator cuff syndrome, and diagnoses were accepted as each study presented them. Few studies were available for each risk factor, and the authors say publication bias, where positive results get published and null results do not, is a real possibility here. Because the designs were observational, the authors cannot establish which came first, the comorbidity or the shoulder problem, and state plainly that cause cannot be inferred. The authors could not tell whether poorly controlled diabetes, blood pressure or lipids carry more risk than well-controlled disease. Confounding by occupation could not be adjusted for in the included studies. Two studies accounted for more than 96% of the weight in the diabetes analysis, so that pooled estimate rests mostly on them. Most included studies were rated at moderate or higher risk of bias, mainly because they did not adjust for confounding factors, followed by lack of temporality and selection of controls. Only English-language articles were included.

Do not read the raised odds for high blood pressure as a reason to treat blood pressure to protect the shoulder. The authors call that evidence severely biased and say they are not confident in it, and the only cohort study that measured blood pressure before the tear appeared found no association.