Abstract
BACKGROUND: Chronic migraine is a disabling and prevalent neurological disease that significantly impacts patients' quality of life. OnabotulinumtoxinA (OnabotA) is a safe and effective chronic migraine preventive treatment. The objective was to evaluate adherence to the recommended time interval between consecutive OnabotA injections according to the Phase III Research Evaluating Migraine Prophylaxis Therapy (PREEMPT) protocol, and to analyze changes in the interval adherence before and after the introduction of an Advanced Practice Nurse (APN) in a specialized Headache Unit of a tertiary hospital. METHODS: This was a retrospective study performed in a Spanish specialized Headache Clinic. Patients diagnosed with chronic migraine and treated with OnabotA following the PREEMPT protocol were included, before and after the introduction of APNs. Treatment was considered interval-compliant if the injection interval ranged from 75 to 105 days. The data collected included three 18-month periods. Statistical analyses examined differences across periods using R-Studio. RESULTS: A total of 2991 participants were included, of whom 83.8% (2507/2991) were women, with a median age [interquartile range (IQR)] of 48.0 [40.0-57.0] years old. A statistically significant association between the introduction of the APN and improved adherence to the PREEMPT protocol was observed over time (Z = -19.60, p < 0.001). Adherence rates increased from 52.1% in P1 to 76.1% in both P2 and P3. The median time between visits decreased from 105 days in P1 to 96 days in P2, with a slight increase to 98 days in P3. CONCLUSION: The involvement of advanced practice nurses in OnabotA administration decreased the time interval between infiltrations and improved adherence to the PREEMPT protocol. These findings highlight the APN's role in optimizing patient care.