The effect of diabetes, hyperlipidemia, and statins on the development of rotator cuff disease: a nationwide, 11-year, longitudinal, population-based follow-up study.

BACKGROUND: The intrinsic risk factors of rotator cuff disease (RCD) include degeneration, inflammation, oxidative stress, and circulation impairment. Both diabetes and hyperlipidemia are thought to increase these risk factors and therefore potentially enhance RCD development. However, few studies, and few longitudinal follow-up studies in particular, exist to prove this.

HYPOTHESIS: Both diabetes and hyperlipidemia can increase a patient's risk of developing RCD.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: A total of 498,678 participants, including 28,391 diagnosed with diabetes and 25,621 with hyperlipidemia in the year 2000, were followed for an 11-year period. Multivariate Cox proportional hazards models were used to explore the effect of (1) diabetes, (2) hyperlipidemia, (3) diabetes with/without insulin use, and (4) hyperlipidemia with/without statin use on the development of RCD. In the subgroup of patients with hyperlipidemia, multivariate Cox proportional hazards models were also performed to explore the relationship between statin use and RCD development.

RESULTS: During an 11-year follow-up period, 26,664 patients developed RCD. The crude hazard ratio (HR) for RCD in patients with diabetes as compared with those without diabetes was 2.11 (95% CI, 2.02-2.20; P < .0001). The crude HR for RCD in patients with hyperlipidemia as compared with those without hyperlipidemia was 2.00 (95% CI, 1.92-2.08; P < .0001). Multivariate Cox proportional hazards analysis revealed that, in addition to older age and female sex, both diabetes and hyperlipidemia increased the risk of RCD (diabetes: HR, 1.47 [95% CI, 1.41-1.54]; P < .0001) (hyperlipidemia: HR, 1.48 [95% CI, 1.42-1.55]; P < .0001). An elevated risk still existed in patients with diabetes with/without insulin use (diabetes with insulin use: HR, 1.43 [95% CI, 1.35-1.51]; P < .0001) (diabetes without insulin use: HR, 1.64 [95% CI, 1.53-1.75]; P < .0001). An increased risk also existed in patients with hyperlipidemia with/without statin use (hyperlipidemia with statin use: HR, 1.16 [95% CI, 1.10-1.23]; P < .0001) (hyperlipidemia without statin use: HR, 2.01 [95% CI, 1.89-2.13]; P < .0001). In the subgroup of patients with hyperlipidemia, statin use was associated with a lower risk of developing RCD when compared with no statin use (rosuvastatin: HR, 0.41 [95% CI, 0.35-0.49]; P < .0001) (simvastatin: HR, 0.62 [95% CI, 0.54-0.71]; P < .0001) (other statins: HR, 0.66 [95% CI, 0.60-0.72]; P < .0001).

CONCLUSION: The present longitudinal, population-based follow-up study showed that either diabetes or hyperlipidemia alone was an independent risk factor for RCD development. Statin use might provide protection against RCD in patients with hyperlipidemia.