One-year follow-up of patients with cluster C personality disorders: A prospective study comparing patients with "pure" and comorbid conditions within cluster C, and "pure" C with "pure" cluster A or B conditions

This one-year, post-treatment prospective study of consecutively admitted p atients to a national psychiatric in-patient clinic, compares patients belo nging to four subgroups of DSM-III-R personality disorder (PDs): ''pure clu ster A (N = 21), "pure" B (N = 67), "pure" C (N = 251), and Axis II "comorb id" C (N = 138). Outcome was measured by SCl-90 and occupational status. Ax is I disorders were controlled for in all analyses. Contrary to our hypothesis, patients in pure cluster C had no better outcom e than either Axis II comorbid cluster C patients or patients with pure clu ster A or B, Although pure C patients relapsed in symptom distress after di scharge, comorbid C patients did not. C patients with an additional Histrio nic PD were less at risk to be a case at follow up (GST level > 1.00), Clus ter C disorders as a whole had negative impact upon outcome in the total sa mple, These findings suggest the need for better treatment of patients with clust er C conditions.