Limited joint mobility, dupuytren's contracture and retinopathy in type 1 diabetes: association with cigarette smoking

To examine the associations between cigarette smoking, connective tissue changes, and diabetic retinopathy, a detailed smoking history was elicited from 150 normotensive non‐diabetic subjects, and from 266 randomly selected adult patients with Type 1 diabetes, after examination for limited joint mobility, Dupuytren's contracture, and diabetic retinopathy. Mean insulin dose and current glycosylated haemoglobin concentrations were comparable in diabetic smokers and non‐smokers. The historical duration of smoking correlated with the duration of diabetes (r = 0.72, p < 0.001). In diabetic patients limited joint mobility was positively associated with retinopathy, being found in 73/147 (50%) patients with retinopathy compared with 20/114 (18%) without retinopathy (χ2 = 28.9, p < 0.001), and also with Dupuytren's contracture, 19/34 (56%) of patients with limited joint mobility having Dupuytren's contracture, compared with 76/232 (33%) of patients without Dupuytren's contracture (χ2 = 7.05, p < 0.01). Limited joint mobility was observed in 50% of diabetic smokers compared with 25% of non‐smokers (odds ratio = 2.87 (corrected for diabetes duration), 95% confidence interval 1.64–5.01). Diabetic retinopathy was weakly associated with smoking (odds ratio 1.09; 95% confidence interval 0.60–1.96). There was however an increased prevalence of background retinopathy among male smokers (50% vs 29%; χ2 = 6.88, p < 0.01). In non‐diabetic males limited joint mobility was observed in 37% of smokers but only in 11% of non‐smokers (NS), while 33% of smokers and 8% of non‐smokers had Dupuytren's contracture (p = 0.012). These results suggest that cigarette smoking contributes to the development of extra‐articular connective tissue changes in both diabetic patients and non‐diabetic subjects, and possibly to the development of diabetic retinopathy. 1989 Diabetes UK