Hindsight: Metabolic Rate in Obesity Hypertension
Saturday, February 11, 2012In 2000, one of my doctoral students, Iris Kunz examined the relationship between resting metabolic rate and obesity related hypertension in human volunteers.
Based on our longstanding interest in the sympathetic nervous system, we hypothesized that increased sympathetic the increased sympathetic activity commonly associated with hypertension in obese subjects, would result in higher resting metabolic rates.
For this study we used indirect calorimetry to determine basal substrate use and metabolic rate in 166 normotensive and hypertensive normal weight or obese subjects. It turned out that 42 of the 91 hypertensive subjects were on beta-adrenergic blockers and had significantly reduced metabolic rates – these were excluded from the subsequent analyses.
In the remaining subjects, we found an almost 10% higher metabolic rate in the hypertensive compared to the normotensive subjects. This higher rate was associated with higher levels of plasma catecholamines and leptin, as well as an increased insulin response to an oral glucose load.
In our paper published in HYPERTENSION, we discussed these findings a supporting our hypothesis that the elevated sympathetic activity seen in obese hypertensive subjects would be associated with an increased metabolic rate.
Although these findings may not have any immediate clinical implications, they do provide some insight into how neurogenic and metabolic factors may play a role in obesity hypertension. Certainly, it is always comforting when actual findings are in line with what we would have predicted based on what we know about obesity, sympathetic activity, and metabolic rate.
According to Google Scholar, this paper has been cited 46 times.