Silberstein, Stephen D.

Abstract Objective The objective of this study was to summarize the available evidence regarding the clinical value and trend over time of lumbar cerebrospinal fluid (CSF) opening pressure utilization to diagnose spontaneous intracranial hypotension (SIH). Background CSF opening pressure obtained via lumbar puncture is one of the diagnostic criteria for SIH based on the International Criteria for Headache Disorders, 3rd Edition (ICHD‐3), but it has questionable utility as an initial investigation for diagnosing SIH. Methods The authors performed a systematic literature review and meta‐analysis. PubMed/MEDLINE, Scopus, and Cochrane Library were searched from inception to October 2022. Original studies and case series in English reporting three or more patients with suspected or known SIH and CSF pressure measurement were included. Meta‐analyses and meta‐regression were used to calculate pooled estimates and examine the impact of age, sex, and publication year on outcomes, including CSF pressure < 60 mm CSF, orthostatic headache, and positive findings on brain magnetic resonance imaging (MRI), spinal imaging, and radionuclide studies. Results For every 1‐year increase in the year of publication, the odds of reporting low CSF pressure decreased by 6.20% (adjusted odds ratio [aOR] = 0.94, aOR 95% confidence interval [CI] = [0.90, 0.97], p = 0.001), the odds of reporting a positive brain MRI increased by 4.67% (aOR = 1.05, aOR 95% CI = [1.01, 1.09], p = 0.026), and the odds of reporting orthostatic headache increased by 9.13% (aOR = 1.09, aOR 95% CI = [1.03, 1.15], p = 0.002). Each 1% increase in the percentage of patients with orthostatic headache was associated with a 3.13% increase in the odds of low CSF pressure (aOR = 1.03, aOR 95% CI = [1.01, 1.05], p = 0.003). Similarly, as the percentage of patients with low CSF pressure increased by 1%, there was a 2.53% increase in the odds of orthostatic headache (aOR = 1.03, aOR 95% CI = [1.01, 1.04], p = 0.005). It was estimated that 31.9% of patients with SIH had normal opening pressure (95% CI = [24.0%, 40.8%], prediction interval = [5.0%, 80.5%]). Every 1% increase in the percentage of patients with positive brain MRI was associated with a 5.25% increase in the odds of positive spinal imaging (aOR = 1.05, aOR 95% CI = [1.00, 1.11], p = 0.047). Age and positive radionuclide study did not significantly impact the outcomes measured. The corresponding I 2 for each outcome was reduced by controlling for study‐wide covariates believed to impact the prevalence of each outcome. Sensitivity analyses did not reveal discrepancies in results when studies requiring outcomes of interest were removed. Conclusion Our analysis found that recent studies indicate a reduced reliance on opening pressure for diagnosing SIH. Rather, results suggest an increasing reliance on contrast‐enhanced brain MRI, spine imaging, and clinical features for SIH diagnosis.

Introduction Patients hospitalized for headache treatment pose unique challenges to the healthcare system. Currently, there is a lack of evidence-based guidance on management. This practice advisory aims to fill this critical gap by systematically reviewing the existing literature and providing comprehensive, evidence-based recommendations for managing headache patients during hospitalization. Methods In February 2023, the American Society of Regional Anesthesia and Pain Medicine approved this practice advisory proposal. The steering committee selected committee members based on clinical and research expertise in the field of headache medicine. Nine questions were formulated by the committee, and each question was assigned to a group composed of 3–4 members. A systematic literature search for each question was performed in Medline, Embase, Cochrane Database of Systematic Reviews and Web of Science on June 21, 2023. The results from each search were imported into separate Covidence projects for screening, data extraction, and risk of bias assessment. Additionally, relevant systematic reviews (SR) were screened. Each group submitted a structured narrative review along with statements and recommendations based on the US Preventive Services Task Force (USPSTF) format for grading of evidence. While the USPSTF framework was used, including the language in the recommendations, the formal USPSTF methodology, including the SR with meta-analysis and summary tables with forest plots, was not followed because of low overall evidence quality. The interim draft was shared electronically with each collaborator, who was requested to vote anonymously using two rounds of the modified Delphi approach. A consensus recommendation required >75% agreement. Results The panel generated 12 statements and 17 recommendations, along with their strength and certainty of evidence. Following two rounds of Delphi voting, a high consensus was achieved for all statements and recommendations. Most statements received a low-to-moderate level of certainty, and all but one recommendation received grade B or C, which was consistent with the lack of randomized controlled trials supporting most of the drugs in this document. Conclusions This evidence-based practice advisory provides a foundational step toward standardizing inpatient headache care and highlights existing gaps in the literature that should be addressed through rigorous prospective randomized studies.

Abstract Objective To characterize the long‐term (56‐week) benefits of continuous onabotulinumtoxinA treatment response in individuals with chronic migraine (CM) who achieved reduction to <15 headache days/month with treatment. Background There are limited data exploring reductions in monthly headache days to levels consistent with episodic migraine among those experiencing CM. Understanding the impact of sustained preventive treatment response in CM can provide important information about the impact of successful therapy. Methods The two Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy trials of onabotulinumtoxinA in adults included a 24‐week, randomized, double‐blind, placebo‐controlled phase and a 32‐week open‐label phase. Data were pooled to determine proportions of individuals with <15 headache days/month while on treatment during several time periods in the double‐blind phase (Weeks 21–24; any 12 consecutive weeks; Weeks 13–24) and the entire study (Weeks 53–56; any 12 consecutive weeks; any 4‐week period). We assessed the long‐term impact on mean monthly headache days and changes from baseline on the six‐item Headache Impact Test (HIT‐6) and Migraine‐Specific Quality of Life questionnaire version 2.1 (MSQv2.1). Results We analyzed 1384 participants with chronic migraine (double‐blind: onabotulinumtoxinA, n = 688; placebo, n = 696; open‐label: n = 688 [onabotulinumtoxinA]). The discontinuation rates prior to the completion of the full 56‐week treatment period for onabotulinumtoxinA and placebo were 25.4% ( n = 175) and 29.3% ( n = 204), respectively. During Weeks 13–24 of the double‐blind phase, significantly more onabotulinumtoxinA‐treated (386/688 [56.1%]) than placebo‐treated (342/696 [49.1%]) individuals had <15 headache days/month ( p = 0.010), with fewer monthly headache days for onabotulinumtoxinA versus placebo responders. The proportions of participants achieving <15 monthly headache days with onabotulinumtoxinA were 60.9% (419/688) at Weeks 25–56, 81.1% (558/688) at Weeks 53–56, and 79.4% (546/688) during any consecutive 12‐week period. Mean changes from baseline on the HIT‐6 and MSQv2.1 questionnaire surpassed within‐group minimal important difference thresholds in all periods. At Week 24, onabotulinumtoxinA‐treated participants who achieved <15 monthly headache days during Weeks 21–24 had a greater mean HIT‐6 score reduction (−6.5 vs. −1.4) and greater mean MSQv2.1 Role‐Function Restrictive score improvements (21.3 vs. 6.4) than those who did not achieve <15 monthly headache days during the same period. Conclusions Participants who achieved <15 monthly headache days with onabotulinumtoxinA treatment achieved meaningful benefits in headache‐related disability and migraine‐specific quality of life compared with those who remained at or above the 15–monthly headache days threshold. Sustained benefits observed over 56 weeks support long‐term onabotulinumtoxinA use for the prevention of CM.