Abstract
Purpose: :
Fuchs Corneal Dystrophy (FCD) is a progressive, hereditary disorder of the cornea associated with excrescences of Descemet’s membrane, endothelial dysfunction and corneal edema. Females appear to be more commonly affected relative to males. In our examination of large families with FCD, we sought to determine the extent to which females were disproportionately affected, and if a higher absolute number of females could contribute to the clinical predominance of females among patients presenting with FCD.
Methods: :
Pedigrees from 16 families of patients with FCD were retrospectively selected based on a minimum of 25 individuals per family in a maximum of three generations. A total of 375 individuals were examined by one ophthalmologist at sites proximal to the residence of family members over a period of four years. A positive result was defined as a minimum Krachmer score of 1+ in either eye.
Results: :
Among individuals at risk in families with FCD, clinical examination revealed a significantly higher affectation rate among females (103/153, 67%) than males (60/112, 54%, p=0.016 by Fisher's exact test). Interestingly, independent of affectation status, pedigrees of three consecutive generations in each family demonstrated a significantly higher number of females to males (398 to 327, p<0.01, one-sided paired t-test). Males from families with higher female representation demonstrated a significantly higher affectation rate (32/49, 65%) than those in families with fewer females (28/63, 44%, p=0.02 by Fisher’s exact test).
Conclusions: :
Among large families with FCD, females exhibit greater odds of developing disease than males. However, evaluation across multiple generations reveals an excess of females, a phenomenon that appears independent of affectation status. Although the potential effect of ascertainment bias exists, the results raise the possibility that a factor may exist in families with FCD that increases both the absolute number of females and the development of disease.
Keywords: cornea: basic science • clinical (human) or epidemiologic studies: natural history • genetics