New-onset orthostatic intolerance following bariatric surgery

As bariatric surgery has become an increasingly popular treatment for obesity, we have seen an increasing number of patients present after bariatric surgery with new-onset syncope, near-syncope, and lightheadedness.

We retrospectively reviewed patients who had had bariatric surgery referred to our institution for evaluation of orthostatic intolerance. We reviewed history, physical examination, type of bariatric surgery procedure, and tilt table test results in these patients. There were 14 women and one man with mean age 42 +/- 6 years, preoperative body mass index was 49.3 +/- 6.0 kg/m(2), and mean postoperative weight loss was 55.9 kg. Mean onset of symptoms was 5.2 +/- 3.9 months after surgery. Presenting symptoms were lightheadedness in 15 (100%), near-syncope in 11 (73%), and syncope in nine (60%). All but one patient had a positive tilt table test with eight (53%) having a neurocardiogenic response, three (20%) having a dysautonomic response, and (20%) having a postural tachycardia response. The likely mechanism of orthostatic intolerance is autonomic insufficiency in combination with reverse course of obesity-related hypertension. The majority of the patients (12 out of 15) responded to standard therapy for autonomic insufficiency.

Some patients may develop significant orthostatic intolerance due to autonomic insufficiency following bariatric surgery, and awareness of the potential association between bariatric surgery and new orthostatic intolerance is important for providing timely care.