Clinical predictors of therapeutic failure of occipital nerve stimulation in refractory chronic cluster headache.

BACKGROUND: Occipital nerve stimulation (ONS) is a treatment with evidence in refractory chronic cluster headache (CCH). However, the variable response rate and cost make it necessary to investigate predictors of response. METHODS: This is a cross-sectional study conducted through the review of medical records of CCH patients from six hospitals in Madrid. Epidemiological and clinical variables were compared between patients with ONS failure and the rest. ONS failure was defined as the need for device withdrawal or switch off because of lack of response or adverse events. RESULTS: From a series of 88 CCH, 26 (29.6%) underwent ONS surgery, of whom 13/26 (50.0%) failed because lack of response. ONS failure group had an earlier headache onset (mean ± SD) of 27.7 ± 6.9 vs. 36.7 ± 11.8 years, p = 0.026) and a higher smoking rate (100% vs. 42.9%, p = 0.006). Stational fluctuations (58.3% vs. 7.7%, p = 0.007) and nocturnal exacerbations (91.7% vs. 53.9%, p = 0.035) were more frequent in the ONS failure group as well. There was no difference between groups in diagnostic delay, years of evolution prior to surgery, mental illness, comorbidity with other headache disorders or chronic pain conditions or prior response to occipital nerves anesthetic blocks. CONCLUSIONS: Some clinical features such as an early debut, smoking and seasonal or circadian fluctuations could be related to failure of ONS in refractory CCH.

Evaluation of the concomitant use of prophylactic treatments in patients with migraine under anti-calcitonin gene-related peptide therapies: The PREVENAC study.

BACKGROUND AND PURPOSE: Anti-calcitonin gene-related peptide (CGRP) therapies are recent preventive therapies approved for both episodic and chronic migraine. One of the measures of effectiveness is the withdrawal of other preventive treatments. The objective of this study is to quantify the impact of anti-CGRP drugs in concomitant preventive treatment in patients with migraine. METHODS: This was an observational, retrospective, multicenter cohort study with patients from nine national headache units. Patients with migraine undergoing treatment for at least 6 months with anti-CGRP antibodies, who were initially associated with some preventive treatment (oral and/or onabotulinumtoxinA) were included. Demographic and clinical variables were collected, as well as variables related to headache. Differences according to withdrawal or nonwithdrawal were evaluated. RESULTS: A total of 408 patients were included, 86.52% women, 48.79 (SD = 1.46) years old. Preventive treatment was withdrawn in 43.87% (179/408), 20.83% partially and 23.04% totally. In 27.45% (112/408), it was maintained exclusively due to comorbidity and in 28.6% (117/408) due to partial efficacy. The most frequent time of withdrawal was between 3 and 5 months after the start of treatment. The baseline characteristics associated with nonwithdrawal were comorbidities: insomnia, hypertension and obesity, chronic migraine, and medication overuse. In the multivariate analysis, the absence of high blood pressure, a greater number of preventive treatments at the start, and a lower number of migraine days/month after anti-CGRP treatment were independently associated with withdrawal of the treatment (p < 0.05). CONCLUSIONS: Anti-CGRP antibodies allow the withdrawal of associated preventive treatment in a significant percentage of patients, which supports its effectiveness in real-life conditions.

RE-START: Exploring the effectiveness of anti-calcitonin gene-related peptide resumption after discontinuation in migraine.

BACKGROUND AND PURPOSE: According to the latest European guidelines, discontinuation of monoclonal antibodies against calcitonin gene-related peptide (anti-CGRP MAb) may be considered after 12-18 months of treatment. However, some patients may worsen after discontinuation. In this study, we assessed the response following treatment resumption. METHODS: This was a prospective study conducted in 14 Headache Units in Spain. We included patients with response to anti-CGRP MAb with clinical worsening after withdrawal and resumption of treatment. Numbers of monthly migraine days (MMD) and monthly headache days (MHD) were obtained at four time points: before starting anti-CGRP MAb (T-baseline); last month of first treatment period (T-suspension); month of restart due to worsening (T-worsening); and 3 months after resumption (T-reintroduction). The response rate to resumption was calculated. Possible differences among periods were analysed according to MMD and MHD. RESULTS: A total of 360 patients, 82% women, with a median (interquartile range [IQR]) age at migraine onset of 18 (12) years. The median (IQR) MHD at T-baseline was 20 (13) and MMD was 5 (6); at T-suspension, the median (IQR) MHD was 5 (6) and MMD was 4 (5); at T-worsening, the median (IQR) MHD was 16 (13) and MMD was 12 (6); and at T-reintroduction, the median (IQR) MHD was 8 (8) and MHD was 5 (5). In the second period of treatment, a 50% response rate was achieved by 57.4% of patients in MHD and 65.8% in MMD. Multivariate models showed significant differences in MHD between the third month after reintroduction and last month before suspension of first treatment period (p < 0.001). CONCLUSION: The results suggest that anti-CGRP MAb therapy is effective after reintroduction. However, 3 months after resumption, one third of the sample reached the same improvement as after the first treatment period.

The profile of refractory chronic cluster headache.

INTRODUCTION: Chronic cluster headache (CCH) is a relatively rare primary headache disorder whose management is often challenging. The prevalence of refractory CCH (rCCH) is unknown. Our aim is to describe the frequency of rCCH within a population of CCH, define the clinical profile of the refractory patients and the treatments they underwent. METHODS: We conducted a cross-sectional study through a review of the medical records of CCH patients in six hospitals in Madrid, Spain. Data on epidemiological, clinical presentation, treatment and disease activity at the moment were collected. The European Headache Federation diagnostic criteria were used for rCCH definition. High disease activity was defined as having at least 3 severe attacks per week that impact quality of life despite treatment. Non-rCCH and rCCH groups were compared. RESULTS: 88 CCH patients were analyzed, 68.2% (60/88) met rCCH criteria at some point in their evolution. A longer diagnostic delay (4.6 ± 7.1 vs. 3.2 ± 3.7 years, p = 0.017) was observed in rCCH. All rCCH patients tried therapies without established evidence from randomized clinical trials. OnabotulinumtoxinA and galcanezumab were initiated in 77.3% (68/88) and 5.7% (5/88), but discontinued in 52.9% (36/68) and 60.0% (3/5), respectively. Occipital nerve stimulation (ONS) was implanted in 29.6% (26/88), with 50.0% (13/26) still active. Other treatment options are described and discussed. Despite treatment, 60.2% (53/88) still have high disease activity. CONCLUSION: CCH is a disorder with poor prognosis, meeting refractoriness criteria in more than half. OnabotulinumtoxinA and ONS could be the effective in refractory patients.