Abnormalities of Anthropometric,Hemodynamic, and Autonomic Variables in Offspring of Hypertensive Parents

Young adult offspring of hypertensive parents (pHTN⊕) are a good model for assessing abnormalities of anthropometric, cardiometabolic, and autonomic variables prior to clinical hypertension. The objectives of this study were to determine whether these variables and autonomic responses to oral carbohydrates were altered in offspring of pHTN⊕. Two hundred consecutive patients, including 100 pHTN⊕, were evaluated, with 29 patients, including 14 pHTN⊕, given a 70‐gram carbohydrate load. The pHTN⊕ group had higher blood pressure, pulse pressure, abdominal circumference (AC), weight, body mass index, and basal metabolic rate than offspring of normotensive parents (pHTN∅). At baseline, the low‐frequency (LF, sympathetic) to high‐frequency (HF, parasympathetic) ratio, assessed by spectral analysis of heart rate variability, was similar in both groups. After the carbohydrate load, the LF/HF ratio was greater in offspring of pHTN⊕. pHTN⊕ individuals have abnormalities of anthropometric and hemodynamic variables at baseline and autonomic responses to oral carbohydrates before developing hypertension.

Hypertension is associated with a large and growing health and economic burden of cardiovascular and renal diseases.¹, ² High arterial pressure causes target organ changes in the brain, heart, vessels, and kidneys. The etiology of arterial hypertension is unknown in most cases, although genetic factors play an important role.³ Environmental and behavioral factors also participate and include excessive salt and alcohol intake, stress, smoking, sedentary lifestyle, and obesity. Obesity is commonly associated with hypertension and appears to begin early in offspring of hypertensive parents (pHTN⊕).⁴, ⁵ The offspring of pHTN⊕ are more likely to develop hypertension than those of normotensive parents (pHTN∅).⁴ Normotensive offspring of pHTN⊕ have higher casual arterial pressure than normotensive offspring of pHTN∅.⁴ The difference in arterial pressure between children of pHTN∅ and children of pHTN⊕ has been reported in infancy, childhood, adolescence, and adulthood.⁶ Anthropometric data such as body mass index (BMI), waist circumference, and neck circumference might be related to the pathogenesis of hypertension in the offspring of pHTN⊕. However, there is no consensus regarding this issue.⁷, ⁸, ⁹ The interrelation between offspring of pHTN⊕ and both anthropometric and environmental variables can result in increased blood pressure (BP) in patients with familial predisposition, ie, gene‐environment interactions.¹⁰ Although associations between hypertension and anthropometric, metabolic, and autonomic nervous system variables were reported,¹¹, ¹², ¹³ few studies have addressed this association in offspring of pHTN⊕ parents.The sympathetic nervous system plays an important role in the pathogenesis of arterial hypertension. Greater activity of the sympathetic nervous system leads to lower heart rate variability (HRV) and higher risk for cardiovascular events, such as myocardial infarction and sudden death.¹⁴, ¹⁵ Conversely, higher parasympathetic nervous system activity increases HRV and is associated with lower heart‐related mortality. Autonomic nervous system regulation in hypertensive patients appears to be altered, and the changes can be detected through spectral analysis.¹⁵ Autonomic nervous system changes can be affected by environmental factors including food intake, and may be modulated by family history. Inappropriate increase in sympathetic activity after any kind of challenge in normotensive patients could be indicative of autonomic imbalance preceding the onset of hypertension. In one report, normotensive offspring of pHTN⊕ show increased sympathetic activity at baseline and after isometric exercise.¹⁶ Carbohydrate consumption can have a negative effect on sympathetic activity in hypertensive patients.¹⁷ However, the impact of carbohydrate ingestion on autonomic balance has not been reported in normotensive offspring of pHTN⊕.The aim of this study was to assess anthropometric, hemodynamic, and metabolic variables, including basal metabolic rate, in pHTN⊕ and pHTN∅ offspring prior to the onset of hypertension. In a subset of pHTN⊕ and pHTN∅ offspring, autonomic function was assessed under fasting conditions and following an oral carbohydrate load.