Predictors of shoulder pain and shoulder disability after one year in diabetic outpatients

OBJECTIVE: To investigate factors associated with changes in shoulder pain and disability in diabetic outpatients over 1 yr. METHODS: Cross-sectional study with 12-month follow-up in diabetic outpatients (n = 179) using the shoulder pain and disability index (SPADI) and SF-36 version 2. RESULTS: Patients with diabetes and shoulder pain or disability are more likely to be older and female. After 12 months of follow-up, one-quarter of participants without pre-existing symptoms at baseline developed clinically significant pain (28%) or disability (25%). Of the patients with pre-existing shoulder pain or disability, half reported clinically significant worsening (10 percentage points) in shoulder pain (58%) or disability (45%) over 12 months. Few patients demonstrated clinically significant improvement in pain (11%) or disability scores (19%). The remaining one-third of the patients reported no change in symptoms (30% pain; 35% disability). Increasing intensity of pain scores between baseline and 12 months was associated with older age, higher HbA(1c) and less pain at baseline. Increasing disability score between baseline and 12 months was associated with having had eye laser surgery, greater pain at baseline and less disability at baseline. CONCLUSION: Shoulder pain and disability are common, and persistent in adults with diabetes. Having higher HbA(1c) levels or having had treatment for retinopathy was associated with worsening shoulder pain and disability, confirming that glycaemic control and diabetic complications are associated with worsening shoulder pain or disability over 12 months of observation.