Early and annual projected savings from anti-CGRP monoclonal antibodies in migraine prevention: a cost-benefit analysis in the working-age population.

BACKGROUND: Migraine is one of the main causes of disability worldwide. Anti-CGRP monoclonal antibodies (MAbs) have proven to be safe and efficacious as preventive migraine treatments. However, their use is restricted in many countries due to their apparently high cost. Cost-benefit studies are needed. OBJECTIVE: To study the cost-benefit of anti-CGRP MAbs in working-age patients with migraine. METHODS: This is a prospective cohort study of consecutive migraine patients treated with anti-CGRP MAbs (erenumab, fremanezumab and galcanezumab) following National reimbursement policy in a specialized headache clinic. Migraine characteristics and the work impact scale (WPAI) were compared between baseline (M0) and after 3 (M3) and 6 months (M6) of treatment. Using WPAI and the municipal average hourly wage, we calculated indirect costs (absenteeism and presenteeism) at each time point. Direct costs (emergency visits, acute medication use) were also analysed. A cost-benefit study was performed considering the different costs and savings of treating with MAbs. Based on these data an annual projection was conducted. RESULTS: From 256 treated working-age patients, 148 were employed (89.2% women; mean age 48.0 ± 8.5 years), of which 41.2% (61/148) were responders (> 50% reduction in monthly headache days (MHD)). Statistically significant reductions between M0 and M3/M6 were found in absenteeism (p < 0.001) and presenteeism (p < 0.001). Average savings in indirect costs per patient at M3 were absenteeism 105.4 euros/month and presenteeism 394.3 euros/month, similar for M6. Considering the monthly cost of anti-CGRP MAbs, the cost-benefit analysis showed savings of 159.8 euros per patient at M3, with an annual projected savings of 639.2 euros/patient. Both responders and partial responders (30-50% reduction in MHD) presented a positive cost-benefit balance. The overall savings of the cohort at M3/M6 compensated the negative cost-benefit balance for non-responders (< 30% reduction in MHD). CONCLUSION: Anti-CGRP MAbs have a positive impact in the workforce significantly reducing absenteeism and presenteeism. In Spain, this benefit overcomes the expenses derived from their use already at 3 months and is potentially sustainable at longer term; also in patients who are only partial responders, prompting reconsideration of current reimbursement criteria and motivating the extension of similar cost-benefit studies in other countries.

Migraine worsening after COVID-19 and COVID-19 vaccination: Are we facing a nocebo effect?

BACKGROUND AND PURPOSE: In clinical practice patients may report migraine worsening as a consequence of COVID-19 (either infection or vaccines), however, data in this area are lacking. We aimed to investigate the link between COVID-19 and COVID-19 vaccination with migraine worsening and its associated factors. METHODS: An online survey was sent to migraine patients followed up in a Spanish Headache Clinic, collecting demographic data, and information regarding SARS-CoV-2 infection and vaccination. We asked patients if they had noticed worsening of their migraine after these events and assessed concerns about infection, vaccination and migraine worsening. We also extracted data from participants' own electronic diaries (e-diaries), including 1-month data before and after their reported infection and/or vaccination. We compared participants who self-reported migraine worsening since infection or vaccination with those who did not. RESULTS: Of 550 participants, 44.9% (247/550) reported having had COVID-19 at least once and 83.3% (458/550) had been vaccinated. Sixty-one patients reported migraine worsening since COVID-19 and 52 since the vaccination. Among the risk factors for perceived migraine worsening in the two settings (infection and vaccination) was concern about migraine worsening itself (infection: odds ratio [OR] 2.498 [95% CI: 1.02-6.273], p = 0.046; vaccination: OR 17.3 [95% CI: confidence interval 5.3-68], p < 0.001). e-diary information was available for 136 of the 550 patients, 38.2% (52/136) for COVID-19 and 39.7% (54/136) for vaccination. We observed no significant difference in headache frequency 1 month before and after infection or vaccination, even when comparing patients with and without self-reported migraine worsening. CONCLUSIONS: Our preliminary data point to a negligible role of the infection and vaccination on migraine worsening and to the possible presence of a nocebo effect in these settings, as a remarkable proportion of patients had a clear perception of migraine worsening.

Thermal Analysis of a MEMS-Based Self-Adaptive Microfluidic Cooling Device.

This study presents a thermal analysis of a temperature-driven microfluidic cell through a nonlinear self-adaptive micro valve that provides the mechanisms for the system to maintain a given critical temperature in an efficient way. For the description of the dynamics of the microfluidic cell, a system of two ordinary differential equations subjected to a nonlinear boundary condition, which describes the behavior of the valve, is proposed. The solution of the model, for determined conditions, shows the strong nonlinearity between the overall thermal resistance of the device and the heat flux dissipated due to the action of the thermostatic valve, obtaining a variable thermal resistance from 1.6 × 10-5 to 2.0 × 10-4 Km2/W. In addition, a stability analysis of the temperature-driven microfluidic cell is presented. The stability of the device is essential for its proper functioning and thus, to prevent its oscillating behavior. Therefore, this work focuses on assessing the range of design parameters of the self-adaptive micro valve to produce a stable behavior for the entire system. The stability analysis was performed by studying the linear perturbation around the stationary solution, with the model solved for various heat flows, flow rates, and critical temperatures. Finally, a map of the design parameters space, which specifies the region with asymptotic stability, was found. In this map, the critical temperature (temperature at which the valve initiates the buckling) plays and important role.