Prevalence of psychiatric disorders in patients with chronic solvent induced encephalopathy (CSE)

Abstract

Introduction: Long term occupational exposure to organic solvents may induce chronic solvent-induced encephalopathy (CSE), characterized by mild to severe cognitive impairment, generally seen as the key diagnostic feature. Psychiatric disorders are often diagnosed in subjects with CSE, but were never studied in more detail. This study was designed to establish the prevalence rates of DSM IV mood, anxiety, and alcohol and substance related disorders in patients with CSE.

Materials and methods: In CSE, n=203 (consecutively recruited between 2002 and 2005), defined according to the criteria of the World Health Organisation (WHO), one month prevalence rates of DSM IV mood, anxiety, and life time alcohol/substance related disorders were assessed using the Structured Clinical Interview for DSM IV disorders (SCID). These prevalences were compared with those from an age and gender matched community sample (n=3212) while controlling for insufficient neuropsychological test effort.

Results: In CSE, prevalence rates for major depressive disorder (n=36, relative risk (RR)=7.4), dysthymia (n=15, RR=6.0), panic disorders (n=18, RR=7.1), agoraphobia (n=7, RR=5.5) and generalized anxiety disorder (n=19, RR=15.8) were increased. Reduced prevalence rates were found for alcohol related disorders (n=21, RR=0.3). Insufficient neuropsychological test effort was not associated with increased prevalence rates of DSM IV disorders in subjects suspected of CSE.

Discussion and conclusions: In conclusion, in this first large scale study in patients with CSE, prevalence rates of DSM IV mood and anxiety disorders were elevated as compared with those in the general community, while the prevalence rates of alcohol related disorders were reduced. Further study must determine whether CSE, and mood and anxiety disorders, share a same, solvent induced, neurobiological pathway, supporting the use of a more inclusive diagnostic approach. Additionally, randomised controlled trials are needed for the urgent issue of how to treat mood and anxiety disorders in CSE patients effectively.