Differences in the personality profile of medication-overuse headache sufferers and drug addict patients: a comparative study using MMPI-2

Background.- Medication-overuse headache (MOH) refers to headache attributed to excessive use of acute medications. The role of personality needs studies to explain the shifting from drug use to drug abuse. The main aim of this study is to study personality, according to Minnesota Multiphasic Personality Inventory, comparing MOH, episodic headache, substance addicts (SA) vs healthy controls. Methods.- Eighty-two MOH patients (mean age 44.5; 20 M, 62 F) and 35 episodic headache (mean age 40.2; 8 M, 27 F), were compared to 37 SA (mean age 32.5; 29 M, 8 F) and 37 healthy controls (mean age: 32.49; 20 M, 17 F). International Classification of Headache Disorders 2nd Edition criteria were employed. Chi-square test, Kruskal-Wallis test, and post hoc comparisons were used for statistics. Results.- MOH patients scored higher on Hypochondriasis, Depression (only females), Hysteria (only females) (P <.000). MOH did not show higher scores than episodic headache or healthy controls in dependency scales, while SA did. Conclusion.- The data obtained show that MOH and SA do not share common personality characteristics linked to dependence. Although further studies are needed to understand if such a difference is related to instrumental characteristics or to yet undiscovered psychobiological characteristics of MOH patients; however, we hypothesize that the detected difference may rely on the fact that drug dependence in the 2 groups is promoted by entirely different needs: pleasure seeking in the SA group, pain avoidance in the MOH group.