The epidemiologic characteristics and clinical course of ophthalmopathy associated with autoimmune thyroid disease in Olmsted County, Minnesota.

Among incident cases of GO in Olmsted County, Minnesota: GO affected females six times more frequently than males (86% versus 14% of cases, respectively). The age-adjusted incidence rate was 16 cases per 100,000 population per year for females and 2.9 cases per 100,000 population for males. The peak incidence rates were bimodal, occurring in the age groups 40 to 44 years and 60 to 64 years in females and 45 to 49 years and 65 to 69 years in males. Among patients with GO, approximately 90% had Graves' hyperthyroidism, 1% had primary hypothyroidism, 3% had Hashimoto's thyroiditis, and 5% were euthyroid. Eyelid retraction was the most common ophthalmic feature of autoimmune thyroid disease, being present either unilaterally or bilaterally in more than 90% of patients at some point in their clinical course. Exophthalmos of one or both eyes affected approximately 60% of patients, restrictive extraocular myopathy was apparent in about 40% of patients, and optic nerve dysfunction occurred in either one or both eyes in 6% of patients with autoimmune thyroid disease. Only 5% of patients had the complete constellation of classic findings: eyelid retraction, exophthalmos, optic nerve dysfunction, extraocular muscle involvement, and hyperthyroidism. Upper eyelid retraction, either unilateral or bilateral, was documented in approximately 75% of patients at the time of diagnosis of GO. Lid lag also was a frequent early sign, being present either unilaterally or bilaterally in 50% of patients at the initial examination. At the time of diagnosis of GO, the most frequent ocular symptom was pain or discomfort, which affected 30% of patients. Some degree of diplopia was noted by approximately 17% of patients, lacrimation or photophobia was present in about 15% to 20% of patients, and 7.5% of patients complained of blurred vision. Decreased vision attributable to optic neuropathy was present in less than 2% of eyes at the time of diagnosis of GO. Thyroid dermopathy and acropachy accompanied GO in approximately 4% and 1% of patients, respectively. Myasthenia gravis occurred in less than 1% of patients. Superior limbic keratoconjunctivitis was documented in less than 4% of patients. The median age at the time of diagnosis of GO was 43 years (range, 8 to 88). Among patients with hyperthyroidism, 61% developed ophthalmopathy within 1 year of the onset of thyrotoxicosis. Symptoms and signs for which statistically significant changes occurred between the initial and final examinations included lacrimation, pain or ocular discomfort, photophobia, eyelid retraction, lid lag, eyelid fullness, conjunctival injection, chemosis, and exophthalmos.(ABSTRACT TRUNCATED AT 400 WORDS)