Familial Associated Idiopathic Urethral Stricture Disease: An Assessment Using Pedigree Data From the Utah Population...

To elucidate the role of familial transmissibility of idiopathic urethral stricture disease (USD) using the Utah Population Database.

To identify patients with idiopathic USD, we excluded: post-infective, post-traumatic, post-operative, and hypospadias-related USD. Each idiopathic stricture case was matched to a control (1:1). All male relatives (first to third degree) of cases and controls were identified. A Cox proportional hazards model was performed to assess the effect of being an idiopathic USD case relative vs control relative. Models including all male relatives separated by degree of relationship to index case were performed.

We identified 7939 cases of idiopathic USD which were matched 1:1 to 7015 controls. For a total cohort of 120,792 patients, 60,694 and 60,098 relatives of cases and controls were identified. Median follow-up for the entire cohort was 25.7 years (interquartile range [IQR]; 13.4, 27.4). First-, second-, and third-degree relatives contributed 14.3%, 28.1%, and 57.7% of the cohort, respectively. Three hundred and twenty-eight cases (0.54%) of idiopathic USD were identified within relatives of an idiopathic USD case compared to 122 cases (0.2%) within the control population (P <.001). Hazard ratios estimating effect of being an idiopathic USD case relative vs control relative included any relation (hazards ratio [HR] 2.6; P <.001), first-degree (HR 14.0; P <.001), second-degree (HR 1.7; P = .02), and third-degree (HR 1.3; P = .12).

When compared to control relatives, those with idiopathic USD were more likely to have family members also affected with idiopathic USD, suggesting a familial transmission pattern of idiopathic USD.