Diabetic vitrectomy in a large type 1 diabetes patient population: long-term incidence and risk factors

PURPOSE: Diabetic vitrectomy represents an end-point of diabetic retinopathy progression. This study was designed to estimate long-term incidence of diabetic vitrectomy and associated risk factors.

METHODS: Retrospective review of prospectively collected data from a large diabetes centre between 1996 and 2010. Surgical history was obtained from The Danish National Patient Register.

RESULTS: The population consisted of 3980 patients with type 1 diabetes. Median follow-up was 10.0 years. In total, 106 patients underwent diabetic vitrectomy in the observation period. Surgery indications were nonclearing vitreous haemorrhage (43%) or tractional retinal detachment (57%). The cumulative incidence rates of diabetic vitrectomy were 1.6% after 5 years and 2.9% after 10 years. When excluding patients with no or mild diabetic retinopathy, the corresponding rates were higher; 3.7% and 6.4%, respectively (p < 0.001, log-rank test). The risk of reaching diabetic vitrectomy increased in patients experiencing glycosylated haemoglobin A1c > 75 mmol/mol in the observation period (p < 0.001, hazard ratio: 3.9, Cox regression analysis). Systolic blood pressure ≥ 140 mmHg, diastolic blood pressure ≥ 90 mmHg, diabetes duration, age, gender and nephropathy were not associated with an increased risk of reaching diabetic vitrectomy (p > 0.05 for all variables).

CONCLUSIONS: Diabetic vitrectomy is rarely required in a type 1 diabetes population with varying degrees of retinopathy, but the risk increases markedly with poor metabolic control.