Diagnostic accuracy of hair analysis for the detection of triptan overuse in migraineurs

Prescription drugs abuse is an important cause of mortality, morbidity, and healthcare expenditure worldwide. Chronic migraineurs frequently overuse triptans (almotriptan, eletriptan, frovatriptan, naratriptan, rizatriptan, sumatriptan and zolmitriptan), which are selective 5-HT1B-D agonists and specific anti-migraine drugs. Routine methods to monitor triptan overuse in clinical settings are currently lacking. The aim of this study is to assess the accuracy of hair analysis in detecting triptan overuse. One hundred and fifty migraineurs were diagnosed as triptan overusers or occasionally users according to the criteria of The International Classification of Headache Disorders, 3rd edition (beta version), calculating the doses of triptans taken in the last 3 months from the headache diary. For every patient a nuchal hair sample was collected and 3 centimetres-long proximal section was analysed by LC-MS/MS with a validated method. The accuracy of hair analysis in detecting triptan overuse was analysed with receiver operating characteristic (ROC) curve analysis; the cut-off of hair concentrations discriminating overusers from occasionally users were determined with Liu's method. The accuracy of hair analysis in distinguishing occasionally users from overusers was high for almotriptan (ROC AUC = 0.9013), eletriptan (ROC AUC = 0.8305), rizatriptan (ROC AUC = 0.9250) and sumatriptan (ROC AUC = 0.9015). The cut-off of hair concentrations discriminating overusers from occasionally users were: 526 pg/mg for almotriptan (sensitivity = 77%, specificity = 96%), 789 pg/mg for eletriptan (sensitivity = 83%, specificity = 75%), 179 pg/mg for rizatriptan (sensitivity = 88%, specificity = 95%) and 139 pg/mg for sumatriptan (sensitivity = 83%, specificity = 91%). Hair analysis is an accurate method to discriminate between occasional and triptan overuse.