Genetic risk of rhegmatogenous retinal detachment: a familial aggregation study.

OBJECTIVE To investigate the magnitude of the genetic risk of nonsyndromic rhegmatogenous retinal detachments (RRDs) in a familial aggregation study. DESIGN Two hundred three consecutive patients with RRD and 461 controls without RRD were ascertained at the Department of Ophthalmology of the University Medical Centre Nijmegen in Nijmegen, the Netherlands. Data on family composition, history of RRD, and presence of other risk factors in siblings and offspring were collected by means of a questionnaire. Diagnosis of RRD was confirmed by evaluation of medical records. RESULTS One hundred eighty-one patients (89.2% of those eligible) and 408 controls (88.5% of invited controls) with 1090 and 2345 relatives, respectively, were included in the analysis. Thirteen familial RRDs (1.2%) were diagnosed in 10 case probands and 9 RRDs (0.4%) in 8 control probands. Siblings and offspring of cases had a higher incidence of RRD independent of age, sex, and myopia. The cumulative lifetime risk of RRD was 7.7% for relatives of cases and 3.0% for relatives of controls, yielding a risk ratio of 2.6 (95% confidence interval, 1.1-6.2). CONCLUSIONS Familial occurrence of RRD is a risk factor for RRD. Genetic factors apart from myopia may explain the increased familial risk.