Diabetes mellitus: A risk factor in patients with Graves' orbitopathy

Aims-To assess the prevalence of dysthyroid optic neuropathy (DON) in patie nts with diabetes mellitus (DM) and Graves' orbitopathy (GO) and to investi gate the complications of surgery for GO in these patients. Methods-The records of 482 consecutive patients with GO referred in a 5 yea r period were studied. Those patients who also had DM were selected for fur ther study. The prevalence of insulin dependent diabetes mellitus (IDDM) an d non-insulin dependent diabetes mellitus (NIDDM) was registered, as well a s the prevalence and course of DON. In the patients who underwent surgery f or GO the postoperative complications were recorded. Results-Out of 482 patients with GO, 15 (3.1%) also had DM. Eight (1.7%) ha d IDDM, 7 (1.4%) had NIDDM. Five patients (33.3%) three with IDDM and two w ith NIDDM developed DON with 50% improvement of visual acuity after treatme nt, whereas in the whole population of 482 GO patients 19 had DON (3.9%), s howing 69.4% improvement of vision after treatment. 10 patients with GO and DM were operated for GO; in one of them an optic atrophy developed as a re sult of a postoperative haemorrhage directly after a three wall orbital dec ompression by coronal approach. No other postoperative complications occurr ed. Conclusions-The prevalence of IDDM in patients with GO is higher than in th e normal population. DON occurs much more frequently in patients with GO an d DM than in the total group of GO patients and seems to have a worse visua l prognosis.