Bariatric Surgery Shows Promise in Idiopathic Intracranial Hypertension

Elevated cerebrospinal fluid (CSF) pressure, a hallmark of idiopathic intracranial hypertension (IIH), was reduced after bariatric surgery, the randomized IIH:WT trial showed.

“The study’s findings indicate that, among women with idiopathic intracranial hypertension and a body mass index of 35 or higher, bariatric surgery is an effective treatment to reduce intracranial pressure and for sustained disease remission,” wrote Alexandra Sinclair, PhD, of University of Birmingham in England, and co-authors in JAMA Neurology.

The primary outcome intention-to-treat analysis included data from 54 participants and showed a significantly lower 12-month opening CSF pressure at lumbar puncture for the bariatric surgery group compared with those in a community weight loss program (adjusted mean difference −6.0 cm CSF, 95% CI −9.5 to −2.4, P=0.001). CSF pressure decreased only minimally in the weight management group.

At 12 months, weight was significantly lower in the bariatric surgery group than in the weight management group (adjusted mean difference −21.4 kg, 95% CI −32.1 to −10.7 kg, P<0.001).

Sinclair and colleagues randomized 66 women (mean age, 32) with active IIH to bariatric surgery or a community weight loss program (n=33 for both groups). Mean baseline body mass index (BMI) was about 44 overall. Evaluations were obtained at baseline and 3, 6, 12, and 24 months with planned five-year follow-up.

A quality-of-life survey showed significant improvements favoring bariatric surgery at 12 and 24 months in domains related to physical functioning, fatigue, and overall health, but no differences were seen between the two groups for papilledema or visual acuity. “There was no evidence of improvement in IIH symptoms in either group,” the researchers noted.

“Although it intuitively seems that the clinical aspects of IIH would improve commensurate with decreases in CSF pressure, this was not the case in the study,” wrote Deborah Friedman, MD, MPH, of the University of Texas Southwestern Medical Center in Dallas, in an accompanying editorial.

IIH presents variably with headaches, neck pain, tinnitus, papilledema, diplopia, and visual changes with the possibility of permanent visual loss. It predominantly affects young obese women and is diagnosed when there is raised intracranial pressure without hydrocephalus or a mass lesion and CSF is normal. Consensus guidelines for recognition and treatment have been published.

Reduction of intracranial pressure below 25 cm CSF can relieve symptoms and reduce the risk of visual loss. This may be achieved with diuretics like acetazolamide to reduce CSF production, diagnostic or therapeutic lumbar puncture to remove fluid with rapid but temporary relief of symptoms, or neurosurgical installation of a CSF shunt. Weight loss in the 6-10% range, though often difficult to achieve, may also lead to remission of some symptoms.

The first randomized placebo-controlled clinical trial for IIH evaluated acetazolamide versus placebo in newly diagnosed patients with mild visual field loss. Published in 2014, the Idiopathic Intracranial Hypertension Treatment Trial reported modest improvements of unclear clinical significance for those treated with acetazolamide in addition to a low-sodium diet.

In their study, Sinclair and colleagues enrolled patients between March 2014 and May 2017. The cohort was all female. At baseline, mean lumbar puncture opening pressure was 34.7 cm CSF and about 29% had been treated with acetazolamide.

Bariatric procedures were performed in 27 participants and included Roux-en-Y gastric bypass, gastric banding, and laparoscopic sleeve gastrectomy. Participants in the weight management arm attended a mean of 14.3 Weight Watchers face-to-face sessions, and 57.6% attended at least one session.

No significant differences between groups were seen for papilledema grade, perimetric mean deviation (a measure of global visual field loss), visual acuity, or anxiety and depression scores at 12 or 24 months. However, the surgery group had reduced use of acetazolamide, topiramate, and headache preventive medications during trial in post-hoc analysis.

By 24 months, 24 serious adverse events were reported in 17 patients, with one patient referred for a shunt in year two. There were no deaths in either group.

“Organized weight loss programs offer the advantages of camaraderie, motivation, and ongoing supervision,” Friedman observed. “However, these programs are often not feasible for patients with IIH, who are often so impaired by headaches and visual symptoms that they are unable to work or participate in fee-based dietary programs or exercise plans.”

“Although lumbar puncture opening pressure decreased significantly in participants undergoing bariatric surgery, other outcomes, such as visual function, different symptoms of IIH, and headache disability improved similarly in both treatment groups,” she added. “Nonetheless, there are substantial advantages conferred by bariatric surgery with regard to metabolic syndrome, hypertension, cardiovascular risk, and general medical health.” Sustained improvements in weight and glucose metabolism have been demonstrated for bariatric surgery in those with severe obesity.

Limitations include variation in bariatric procedures performed. Results also may not be generalizable to people with a BMI lower than 35. In addition, more than 40% of participants assigned to the community weight loss program attended none of the scheduled Weight Watchers meetings.

1. Elevated cerebrospinal fluid (CSF) pressure, a hallmark of idiopathic intracranial hypertension (IIH), was reduced after bariatric surgery, a randomized trial showed.

2. No differences between groups were seen for papilledema or visual acuity, and there was no evidence of improvement in IIH symptoms.

Paul Smyth, MD, Contributing Writer, BreakingMED™

Cat ID: 130

Topic ID: 82,130,730,795,130,518,917,159