Lifetime Prevalence of Mood and Anxiety Disorders in Fragile X Premutation Carriers

Objective: The authors studied the lifetime prevalence of DSM-IV-TR psychiatric disorders in a population of adults with the fragile X premutation. Method: The Structured Clinical Interview for DSM-IV was conducted, from 2007-2008, in 85 individuals with the fragile X premutation, 47 with the fragile X-associated tremor/ataxia syndrome (FXTAS; 33 male, 14 female; mean age = 66 years) and 38 without FXTAS (16 male, 22 female; mean age = 52 years). Lifetime prevalence for mood and anxiety disorders among carriers with and without FXTAS was compared to available age-specific population estimates from the National Comorbidity Survey Replication (NCS-R). Results: Among participants with FXTAS, 30 (65%) met lifetime DSM-IV-TR criteria for a mood disorder; 24 (52%) met lifetime DSM-IV-TR criteria for an anxiety disorder. Among the non-FXTAS participants, there were 15 instances of lifetime mood disorder (42%) and 18 of lifetime anxiety disorder (47%). When compared to age-specific NCS-R data, the lifetime prevalences of any mood disorder (P<.0001), major depressive disorder (P<.0001), any anxiety disorder (P<.0001), panic disorder (P=.006), specific phobia (P=.0003), and posttraumatic stress disorder (P=.004) were significantly higher in participants with FXTAS. The lifetime rates of social phobia in individuals with the premutation without FXTAS were significantly higher than NCS-R data (P=.001). Conclusions: This sample of carriers of the fragile X premutation had a notably high lifetime risk of mood and anxiety disorders. Mood and anxiety disorders may be part of the clinical phenotype of the fragile X premutation conditions, especially in carriers with FXTAS. Clinicians encountering these patients are advised to consider FXTAS as a neuropsychiatric syndrome as well as a neurologic disorder. J Clin Psychiatry 2011;72(2):175-182 (C) Copyright 2010 Physicians Postgraduate Press, Inc.