Table 3.

Summary of study characteristics and findings of included studies

Study, country	Study design, level of evidence	Cohort characteristics	No individuals with RCRSP/study sample size	Case definition of RCRSP, pathology reported and duration	Criteria used to classify MetS or cardiometabolic risk factors included	Prevalence of MetS within population (%)	Adjustments for other covariates	Summary
								Findings (OR with 95% CI) or p value	Positive direction of association by UVA or MVA results
Abate et al55 Italy	Case–control study, level III	Age: 59.2 (±7.1) Gender: M (n=65, 36.1%), F (n=115, 63.9%)	180/180	Unilateral shoulder pain with functional limitations, ultrasound examination RCT (full or partial thickness) Unknown duration	No recorded criteria but MetS risk factors meeting definition by WHO: Obesity (BMI kg/m2 calculation). Dyslipidaemia (diagnosis, drugs assumptions and recent blood biomarkers). DM (diagnosis, drugs assumptions and recent blood biomarkers). BP (diagnosis and current systolic reading).	Unable to extract	Age, heavy repetitive work, diabetes	Metabolic risk factors Independently associated in the presence of bilateral tears UVA: Obesity (p=0.017). DM (p=0.004). MVA: BMI (p=0.047). DM (p=0.029).	For RCT MVA, BMI.* MVA, DM.*
Applegate et al66 USA	Cross-sectional, level III	Age: 42.1 (±11.4) Gender: M (n=421, 34.3%), F (n=805, 65.7%)	RC tendon pain 156/1226 GHJT pain 386/1226	Questionnaire and manikin followed by standardised physical examination (palpation, ROM and positive impingement sign) RC tendinopathy Any pain within last 1 month	No recorded criteria but MetS risk factors meeting definition by WHO: Obesity (BMI >30 kg/m2). Dyslipidaemia (>200 mg/dL). DM (diagnosis). BP (diagnosis and current systolic reading).	Unable to extract	Only adjusted for multiple CVD risk factors (gender, BMI, job satisfaction and family problems)	Metabolic risk factors Independently associated in the presence of RC tendinopathy UVA: Higher systolic BP (OR 1.01; 95% CI 1.00 to 1.02, p<0.05). MVA: Multiple CVD risk scores (18+) for RC tendinopathy (OR 5.97; 95% CI 2.12 to 16.83, p<0.008) namely (age, gender, BP, cholesterol and DM). Metabolic risk factors Independently associated in the presence of GHJT pain UVA: DM (OR 1.76; 95% CI 1.07 to 2.91, p<0.05). Hypercholesterolemia (OR 1.45; 95% CI 1.07 to 1.96, p<0.05). Higher systolic BP (OR 1.01; 95% CI 1.00 to 1.02, p<0.05). MVA: Multiple CVD risk scores (18+) for GHJT pain (OR 4.55; 95% CI 1.99 to 10.40, p<0.001) namely (age, gender, BP, cholesterol and DM).	For RC tendinopathy UVA, BP.* MVA, CVD risk score.* For GHJT pain UVA, DM.* UVA, BP. UVA, hypercholesterolemia.* MVA, CVD risk score.†
Djerbi et al67 France	Case–control study, level III	Age: 57.8 Gender: M (n=124, 60%), F (n=82, 40%)	206/306	Undergoing shoulder surgery for RCRSP (preoperative clinical exam, CT arthrography and arthroscopy) RCT Unknown duration	No recorded criteria but MetS risk factors meeting definition by WHO: BP (diagnosis or 140/90 mm Hg). Obesity (BMI >30 kg/m2). DM (FBG >1.26 g/L or if patient treated for type I/II DM). Dyslipidaemia (LDL-C >1.60 g/L, TG >1.50 g/L, HDL-C >0.40 g/L or if taking cholesterol lowering medication).	Unable to extract	No mention	Metabolic risk factors Independently associated in the presence of RCT SCOI 1–3 UVA: Obesity (OR 2.55; 95% CI 1.4 to 4.58, p=0.0017). Higher systolic BP (OR 2.04; 95% CI 1.18 to 3.52, p=0.0102). Dyslipidaemia (OR 7.69; 95% CI 3.35 to 17.25, p<0.0001). RCT SCOI 4 UVA: Obesity (OR 2.105, p=0.0117) Higher systolic BP (OR 4.311, p<0.0001) Dyslipidaemia (OR 2.867, p=0.0004). RCT SCOI 1–3 MVA: Dyslipidaemia (OR 4.920; 95% CI 2.046 to 11.834, p=0.0004). RCT SCOI 4 MVA: Dyslipidaemia (OR 4.920; 95% CI 2.046 to 11.834, p=0.0004). Higher systolic BP (OR 3.215; 95% CI 1.67 to 6.19, p=0.0005).	For RCT SCOI 1–4 UVA, obesity.* UVA, BP.* UVA and MVA, dyslipidaemia.† For RCT SCOI stage 4 (severe) only UVA, dyslipidaemia.* UVA, obesity.* MVA, BP.
Rechardt et al42 Finland	Cross-sectional, level III	Age: 57.8 Gender: M (n=124, 60%), F (n=82, 40%)	175/6237	Physical examination, painful arc, shoulder pain provoked with resistance, manikin GHJT pain and RC tendinopathy >3 months	NCEP ATP III classification: Central obesity (waist circumference >102 cm in males, >88 cm in females). FBG (>110 mg/L). LHDL-C (<40 mg/dL in men and <50 mg/dL in women). BP (diagnosis, 130/85 mm Hg).	Total: 30.2% (n=1884)	Age, sex, residential district and language	Metabolic risk factors Independently associated in the presence of GHJT pain MVA: Central obesity unilateral association in men (BMI >30 kg/m2, OR 1.6; 95% CI 1.1 to 2.3; waist circumference >102 cm OR 2.0; 95% CI 1.5 to 2.8; WHR ‘high’ OR 3.0; 95% CI 1.7 to 5.3). MetS (OR 1.7; 95% CI 1.3 to 2.1). Type II DM (OR 2.2; 95% CI 1.3 to 3.5) was associated with unilateral shoulder pain in men. Central obesity stronger association for women with bilateral shoulder pain (BMI >30 kg/m2, OR 2.2; 95% CI 1.5 to 3.4; waist circumference >88 cm OR 4.2; 95% CI 2.8 to 6.4; WHR high OR 3.6; 95% CI 2.2 to 5.9). Metabolic risk factors Independently associated in the presence of RCT tendinopathy MVA: Obesity (WHR high OR 3.6; 95% CI 2.2 to 5.9) and type I DM (OR 4.1; 95% CI 0.98 to 16.8) was associated with chronic RC tendinopathy in men. Obesity (WHR high OR 2.3; 95% CI 1.2 to 4.3) was associated with chronic RC tendinopathy in women.	For GHJT pain MVA, MetS.* MVA, DM.* MVA, obesity.* For RC tendinopathy MVA, obesity.* MVA, DM.*
Rechardt et al43 Finland	Cross-sectional, level III	Age: 45.0 (±9.8) Gender: M (n=23, 14%), F (n=140, 86%)	36/163	Physical examination and clinical tests, pain intensity scale (0–100), RC tendinopathy <1 month	NCEP ATP III classification: Central obesity (waist circumference >102 cm in males, >88 cm in females). FBG (>110 mg/L). Low HDL-C (<40 mg/dL in men and <50 mg/dL in women). BP (diagnosis, 130/85 mm Hg).	Total: 18% (n=29)	Age, sex	Metabolic risk factors Independently associated in the presence of RC tendinopathy among UESTD MVA: Central obesity (BMI >30 kg/m2, OR 2.1; 95% CI 0.8 to 5.4; WHR >0.9, OR 3.3; 95% CI 1.3 to 8.6; waist circumference OR 3.2; 95% CI 1.4 to 7.4). Dyslipidaemia (low (<1.48 mmol/L) HDL-C (OR 2.7; 95% CI 1.2 to 6.3)>1.08 mmol/L) TG (OR 2.8; 95% CI 1.2 to 6.6).	For UESTD MVA, obesity.* MVA, dyslipidaemia.*
Juge et al68 France	Cohort study, level III	Age: 72.4 (±11) Gender: M (n=17, 35.4%), F (n=31, 64.6%)	48/147	Undergoing shoulder surgery for RCRSP shoulder pain, standard radiography RCRSP Unknown duration	No recorded criteria but MetS risk factors meeting definition by WHO: Obesity (BMI kg/m2 calculation). Dyslipidaemia (diagnosed/use of lipid lowering medication or abnormal dosage TG). Hypertension (diagnosed or use of antihypertensive agents). Type II DM (diagnosed status or use of antidiabetic medication).	Total: 12.9% (n=19)	Age, CVD, hypothyroidism	Metabolic risk factors Independently associated in the presence of RCRSP MVA: 4 MetS criteria (obesity, dyslipidaemia, hypertension and type II DM) than in shoulder osteoarthritis patients (p=0.03). 2 or 3 criteria no association when compared with shoulder osteoarthritis (p=0.14).	For RCRSP MVA, MetS criteria (4/5).*

*P<0.05

†P<0.01

DM diabetes mellitus; BMI, body mass index;BP, blood pressure; CVD, cardiovascular disease; FBG, fasting blood glucose; GHJT, glenohumeral joint; HDL-C, high density lipoprotein cholesterol; NCEP ATP III, National Cholesterol Education Programme (NCEP) Adult Treatment Panel III (ATP III) devised definition for the metabolic syndrome; LDL-C, low density lipoprotein cholesterol;MetS, metabolic syndrome; MVA, multivariate analysis; NOS, Newcastle-Ottawa score; RC, rotator cuff;RCRSP, rotator cuff-related shoulder pain; RCT, rotator cuff tear; ROC, receiver operating characteristic; ROM, range of motion; SCOI, Southern California Orthopaedic Institute - Rotator cuff tear classification system; TG, triglycerides; UESTD, upper extremity soft tissue disorders; UVA, univariate analysis; WHR, waist-to-hip ratio.