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The knowledge of epidemiology of a disease is paramount in identifying preventive measures. Currently there is a paucity of literature on the epidemiologic determinants of childhood onset essential hypertension (EH). We evaluated children with EH, ascertained in a rigorous manner, in a large multiethnic population in a tertiary pediatric hypertension clinic. We enrolled children with and without EH and obtained data by in-person interview of their parents and by direct anthropometric measurements including blood pressures. A total of 148 children (76 hypertension probands, 72 control probands, and males 53%, mean age 12.2 ± 4.3 years) were enrolled. Of these 148 children, 51 pairs were matched 1:1 on ethnicity, gender and age (±2.5 years). In this study we evaluated the demographics, genetic predisposition and a variety of exposures including, socioeconomic, perinatal, lifestyle and environmental, between cases and controls. All measures were similar between cases and controls other than a significantly higher BMI (p = 0.01) and rates of obesity (p = 0.03), and a difference of near-significance in any family history of EH (p = 0.05) higher in cases compared to controls. The odds of obesity was 3.5 times higher among cases than controls. In this study, we evaluated a variety of prenatal and postnatal exposures that could potentially contributed to the EH phenotype in childhood. The findings of the study elucidate the epidemiology of EH in children and two important associated risk factors, any family history of hypertension and a higher body weight.

A large east Texas family with autosomal dominant inheritance of a novel bleeding disorder has been identified. The disorder is characterized clinically by easy bruising, life-threatening bleeding with trauma or surgery, and menorrhagia in affected women. Laboratory studies demonstrated prolongation of the prothrombin time and activated partial thromboplastin time in affected individuals. Paradoxically, assays of known coagulation factors are all within normal limits. To determine the molecular basis of this disease, a candidate gene linkage analysis in this kindred was done. Initially it was hypothesized that the cause of the disease in this family could be an antithrombin III (AT3) mutation that resulted in a constitutively active AT3 in the absence of heparin binding. Linkage studies using DNA from the family and an intragenic polymorphic marker within the AT3 gene showed that the disease mapped to this locus. The coding region and intron/exon junctions of AT3 were sequenced using the proband's DNA, but this analysis failed to identify a mutation. Additional family members were recruited for the study, and 16 polymorphic markers around the AT3 gene were analyzed. Using 2 recombinants, the critical interval for the defective gene was narrowed to approximately 1.5 Mb, centromeric to AT3. The factor V (FV) gene was mapped into the disease interval and sequenced; there were no mutations found. Elucidation of the genetic defect causing the bleeding disorder in this family may reveal a novel protein involved in the coagulation cascade.