Familial aggregation of first degree relatives of children with essential hypertension

Purpose: Determining familial aggregation is an important first step in narrowing the search for disease-causing genes and hence we determined the familial aggregation of EH among first degree relatives of children with EH.Materials and methods: We prospectively enrolled children with EH along with their first degree relatives from a tertiary pediatric hypertension clinic in a large ambulatory care center. We utilized rigorous methodology for blood pressure (BP) measurements and diagnoses of EH to reduce the heterogeneity in the phenotype. For those enrolled, parental BP status was confirmed by in-clinic direct BP measurements. We also enrolled control children without EH along with their first degree relatives from the same pediatric ambulatory center.Results: In our case-control study of 153 families, the odds of having familial EH was more than 3 times higher among the cases than in controls (OR: 3.63, 95% CI: 1.85-7.12) with 71% of the cases and 41% of the controls reporting familial EH. One parent with EH was seen in 88% of the cases and 52% of the controls (OR: 6.92, 95% CI: 2.68-17.84). The odds of at least one parent (compared to neither) with EH was almost 7-fold higher, and odds of having two parents with EH was 14-fold higher among cases versus controls. The risk of EH did not go back from the first degree relative to the second degree relatives.Conclusions: We identified familial aggregation with an increased liability of childhood onset EH with parental EH. The risk of childhood onset EH is more than doubled in the presence of EH in both parents versus in a single parent. Prediction for childhood-onset EH is improved by obtaining a family history of EH in the first degree relatives.