Antecedents of Hypertension: Role of Race and Stress
Condition: Cardiovascular Diseases; Heart Diseases; Hypertension
MeSH terms: Hypertension; Cardiovascular Diseases; Heart Diseases
Study type: Observational

Summary: 
      To determine the role of environmental stressors in the development of hypertension in Black
      and white school-age children from hypertensive families.
    

Detailed description: 
      BACKGROUND:

      The theoretical rationale for the role of environmental stress factors in the development of
      essential hypertension has been outlined in several studies. Briefly, individuals at
      increased risk for essential hypertension are more likely than non-risk cohorts to exhibit
      exaggerated cardiovascular reactivity to environmental stressors. This may be especially true
      for Blacks compared to whites. Furthermore, individuals at risk for developing essential
      hypertension who are subjected to more frequent physical and/or sociopsychological stressors
      may experience frequent feelings of anger and hostility with concomitant exaggerated
      cardiovascular reactivity. Blacks may experience many of these stressors more frequently than
      whites. The exaggerated cardiovascular reactivity, in turn, is associated with complex
      neuroendocrine changes which result in pathophysiological alterations, eventually causing
      chronic elevated blood pressure. Although this rationale has received some empirical support
      in animal and human studies, definitive evidence to support an etiologic role of
      environmental stress factors is still lacking and needs to be tested in a prospective manner.

      DESIGN NARRATIVE:

      The study was cross-sectional and longitudinal. An estimated 1,523 children, 7 to 14 years
      old at baseline, whose families reported essential hypertension, participated in a blood
      pressure screening following medical verification of their family history of hypertension.
      Children whose systolic blood pressures were in the 5th to 25th percentiles or 75th to 95th
      percentiles were recruited. A sample of children was obtained with relatively equal
      distributions by race, age, gender, and blood pressure grouping. Environmental stress factors
      evaluated include: psychophysiological responses to physical and psychological stressors
      including physical exercise testing, video game, and mental arithmetic tests;
      sociopsychological variables including anger and hostility coping styles; and sociostructural
      variables including socioeconomic status and family stability. The environmental risk factors
      were assessed within the context of other hypertension risk factors such as cholesterol
      level, sodium and alcohol intake, tobacco usage, resting blood pressure, and body weight.
      Each child and his parents were followed annually.

      The study was renewed in 1994 and again in 1998 to continue follow-up for an additional four
      years. Follow-up continued of these adolescents and young adults who were 13 to 20 years old
      in 1998. The purpose was to index early markers of preclinical disease including resting
      blood pressure, left ventricular mass, and several new measures including plasma endothelin-1
      (ET-1) and endothelium dependent arterial dilation (EDAD).