By Louise M. Klebanoff, MD
Assistant Professor of Clinical Neurology, Weill Cornell Medical College
Idiopathic intracranial hypertension is an important cause of intractable headaches and may cause permanent loss of vision as a result of chronic papilledema. Weight loss is an effective treatment, and this randomized study demonstrated superior outcomes for both weight loss and reduced intracranial pressure from bariatric surgery compared to community weight-loss programs.
Mollan SP, Mitchell JL, Ottridge RS, et al. Effectiveness of bariatric surgery vs community weight management intervention for the treatment of idiopathic intracranial hypertension: A randomized clinical trial. JAMA Neurol 2021; Apr 26. doi: 10.1001/jamanerol.2021.0659. [Online ahead of print].
Idiopathic intracranial hypertension (IIH) is a chronic, disabling neurological condition in which intracranial pressure (ICP) is elevated in the absence of an intracranial mass. The clinical syndrome is characterized by chronic headaches, vision loss, and reduced quality of life. The vision loss occurs as the result of increased ICP and the development of optic disc swelling or papilledema.
IIH occurs predominantly in women between the ages of 25 and 36 years; weight gain and obesity are major risk factors. As levels of obesity increase worldwide, the incidence of IIH also is increasing.
Although medications, including diuretics and carbonic anhydrase inhibitors, can improve IIH, weight loss, with a reduction of 3% to 15% of body weight, has been associated with disease remission as defined by normalization of ICP and resolution of papilledema. Although community management programs have been associated with modest weight loss, maintaining this weight loss is more challenging. Bariatric surgery has been associated with more sustained and more significant weight loss. Case studies have suggested that bariatric surgery is associated with remission in patients with IIH. The authors hypothesized that bariatric surgery would be superior to community weight management interventions in reducing ICP in patients with IIH.
The authors conducted a multicenter, randomized clinical trial comparing bariatric surgery with community weight management intervention to assess which approach was more effective in decreasing ICP in patients with IIH. The primary endpoint was ICP as measured by lumbar puncture (LP) opening pressure. Patients from five National Health Service hospitals in the United Kingdom were enrolled over a three-year period. At baseline, patients were required to have an ICP greater than 25 cm of cerebrospinal fluid (CSF) and papilledema. The patients were all female, ranging in age from 18 to 55 years, who met diagnostic criteria for IIH, had normal brain imaging studies (including magnetic resonance venography or computed tomographic venography), had a body mass index (BMI) of 35 or higher, and had not been successful in losing or maintaining weight loss. Patients were randomized in a 1:1 ratio to receive community weight management intervention with Weight Watchers or bariatric surgery. The primary outcome was the difference in ICP between the two groups at 12 months. Secondary outcomes included LP opening pressure at 24 months, visual acuity, and health-associated quality of life. The researchers assessed headache symptoms using the six-item Headache Impact Test, symptom frequency, and analgesic medication use.
Between 2014 and 2017, 74 women were assessed for eligibility, with 66 women enrolling in the study. Patients were randomly assigned to either the surgical arm (n = 33) or the weight management arm (n = 33). The clinical trial arms were balanced in terms of baseline characteristics, including age, ethnicity, duration of illness, and LP opening pressure. The mean standard deviation (SD) LP opening pressure in the study population was 35.7 (7.0) cm CSF. Sixty-four women remained in the trial for 12 months and 54 women (81.8%) completed the primary outcome measures; six patients declined surgical intervention and two patients dropped out of the weight management arm. Of the 27 women who had surgical intervention, 12 participants had Roux-en-Y gastric bypass, 10 had gastric banding, and five had laparoscopic sleeve gastrectomy. The mean number of face-to-face weight management sessions attended was 14.3, with 57.6% of participants attending at least one session.
ICP was significantly lower in the surgical arm vs. the weight management arm. At 12 months, the mean (SD) LP opening pressure decreased from a baseline of 34.8 (5.8) cm CSF to 26.4 (8.7) cm CSF in the surgery arm and from 34.6 (5.6) cm CSF to 32.0 (5.2) cm CSF in the weight management arm; the difference in the weight management arm did not reach statistical significance. The adjusted mean standard error (SE) difference in LP opening pressure between the two groups at 12 months was -6.0 (1.8) cm CSF (95% confidence interval [CI], -9.5 to -2.4 cm CSF; P = 0.001). At 24 months, this difference increased to -8.2 (2.0) cm CSF (95% CI, -12.2 to -4.2 cm CSF; P = 0.001). At 12 months, the mean (SE) percentage change in ICP was -32.1% (4.7%) in the surgical arm compared with -2.5% (3.9%) in the weight management arm.
At 12 and 24 months, all measured improvements in weight and BMI were significantly greater in the surgery arm vs. the weight management arm. In terms of percentage of excess weight loss, the mean (SE) difference between the two groups at 12 months was -18.3% (1.9%; 95% CI, -22.1% to -14.6%; P < 0.001); there were similar results at 24 months.
Papilledema was reduced in both arms. Differences in visual function, as measured by perimetric mean deviation between the two arms, was not significant at either 12 or 24 months. Analysis of quality of life using the 36-item Short Form Health Survey showed significant improvements in the domains of energy and fatigue, physical functioning, and general health. Notably, the severity of headache disability, as measured by the Headache Impact Test, was not significantly different between the two study arms.
COMMENTARY
This randomized clinical trial of bariatric surgery in female patients with IIH showed that bariatric surgery was superior to a community weight management program in terms of sustained reduction in ICP, disease remission, and quality of life measures at both 12 and 24 months. Patients undergoing bariatric surgery had significantly greater weight loss.
Interestingly, visual outcomes in the two groups were not significantly different, nor was there a significant difference in headache disability. The significant improvements in quality of life may be the result of the overall benefits of sustained weight loss. Going forward, differences in headache disability between the two interventions could be explored in more detail. However, this study supports the recommendation for consideration of bariatric surgery in patients with IIH who have not been able to attain or sustain adequate weight loss, the primary treatment for this disabling condition.
