Patient-Centered Research: Fatigue and Personality Pathology in the Mentally Ill

PURPOSE: Psychiatric disorders and abnormal personality traits are commonly identified in patients complaining of fatigue, most of whom can be diagnosed to have depressive (D), anxiety (A), somatoform (S) or eating (E) disorders. This study was designed to determine the relationship between the prevalence of severe fatigue and the presence of personality pathology in individuals with these psychiatric disorders. METHODS: We analyzed 1197 referrals to an academic psychosomatic medicine outpatient unit. All patients underwent highly structured standardized psychometric and clinical assessments which allowed the categorical classification into D, A, S, and E groups. Within each group, the self-scored severity of fatigue experienced during the week preceding the evaluation was compared for patients with and without personality disorders (P). RESULTS: The one-week prevalence of severe fatigue was 38% in D (N = 324) and 45% in D + P (N = 139), p = NS; 29% in A (N = 216) and 29% in A + P (N = 79), p = NS; 33% in E (N = 99) and 32% in E + P (N = 53), p = NS; and 20% in S (N = 209) and 34% in S + P (N = 78), p < .01. The difference in fatigue severity was +5% for D + P vs D (p = NS), +1% for A + P vs A (p = NS), −2% for E + P vs E (p = NS) and 32% for S + P vs S (p < .01). The greater severity of fatigue had a significant contribution to the difference in the 14-item index of somatic distress only for S vs S + P (p = .03) CONCLUSION: Severe fatigue may be a marker of personality pathology in patients with unexplained somatic complaints who do not suffer from depressive, anxiety or eating disorders