Cluster of MMPI personality profiles in chronic tension-type headache and predictable response to Fluoxetine

A study was made of the personality profiles of a sample of 51 patients wit h chronic tension-type headache (CTH) employing the Minnesota Multiphasic P ersonality inventory (MMPI). Two clusters were obtained by applying multiva riate classification techniques: cluster 1 (with elevations on scales Hy, D and Hs only) and cluster 2 (exhibiting elevations on most scales except Pd , Mf and Si). Fifty subjects without chronic pain or known psychiatric diso rders, and extracted from the same social setting as the patients, complete d the MMPI as a control group. Fluoxetine treatment was started in the CTH group, with follow-up over a 1-year period. Chi-squared analysis correlatin g the clusters obtained to different pain-related variables and epidemiolog ical parameters revealed a significant association to sex only. There were no differences in therapeutic response between the two clusters. However, t he patients belonging to the less perturbed cluster who exhibited profiles analogous to those of the control population showed significant improvement with respect to the global sample and their own cluster.