Evaluation of Autonomic Dysfunction in Obese and Non-Obese Hypertensive Subjects

Obesity and more specifically, visceral obesity, has been consistently associated with hypertension and increased cardiovascular risk. Epidemiological studies indicate that at least two-third of the prevalence of hypertension can be directly attributed to obesity. Studies also suggest that hypertensive patients have impaired cardiac autonomic function. The objective of the study was to examine any added effects of obesity on cardiac autonomic dysfunction in hypertensive patients. Hypertensive subjects (n=45) between 35-60 years of age were divided into two groups; Group A (n=30) consisted of non-obese hypertensive subjects and Group B (n=15) consisted of obese (BMI≥30kg/m(2)) hypertensive subjects. Cardiac autonomic function was assessed using four tests - Heart rate response to immediate standing (30:15 ratio), standing to lying ratio (S/L ratio), Blood pressure response to immediate standing and Cold Pressor Test (CPT). There were no significant differences for autonomic function tests between obese and non-obese hypertensive subjects (p >0.05). The results showed that there are no significant differences in the cardiac autonomic function responses between obese and non-obese hypertensive subjects.