Surgical Weight Loss Reduces Sympathetic Nerve ActivityTuesday, June 10, 2014
OK, to some folks this may not be all that new a finding – after all the drop in sympathetic nerve activity with weight loss is one of the main reasons that weight loss reduces blood pressure. Unfortunately, it is also one of the main reasons that metabolic rate is reduces with weight loss.
For anyone, who wonders what happens to sympathetic activity following surgical weight loss, a study by Gino Seravalle and colleagues from the University of Milan, Italy, published in HYPERTENSION has some answers.
Their study in patients undergoing sleeve gastrectomy, studied before as well as six and twelve months post surgery not only shows a respectable drop in blood pressure and heart rate but also a marked and persistent decrease in leptin levels and in muscle sympathetic activity as measured by microneurography. They also showed a significant improvement in baroreceptor sensitivity.
Together these data certainly provide strong evidence that massive weight loss (in this case 9 BMI units) induced by sleeve gastrectomy, triggers profound sympathoinhibitory effects, associated with a stable and significant reduction in plasma leptin levels.
Obviously, much of this can be achieved with non-surgical weight loss, except that finding subjects who lose that amount of weight and keep it off for 12 months without surgery is far more difficult (but not impossible) and therefore much harder to study.
Hat tip to Bill Colmers for pointing me to this study.
Seravalle G, Colombo M, Perego P, Giardini V, Volpe M, Dell’Oro R, Mancia G, & Grassi G (2014). Long-Term Sympathoinhibitory Effects of Surgically Induced Weight Loss in Severe Obese Patients. Hypertension PMID: 24866140