Symptom screening in detection of occupational solvent-related encephalopathy

Sensitive and easily applicable methods are needed for early detection of central nervous system adverse effects related to occupational solvent exposure. The present study evaluates how symptom screening works in practice.

A cross-sectional questionnaire survey was conducted on 2,000 construction workers, including painters and carpenters, in Finland. Scores were calculated for symptoms relevant for chronic solvent encephalopathy (CSE). Responses on exposure and health were compared between subjects with high score (N = 28) and all other respondents. The respondents with the highest scores, regardless of their occupation and exposure, were invited for clinical examination to investigate the aetiologies of the symptoms. If the examination resulted in a suspicion of CSE, a multidisciplinary differential diagnostic follow-up procedure was performed.

The respondents with highest symptom scores were more exposed to solvents than those with lower scores (P < 0.001) and reported more often physician-diagnosed diseases, especially psychiatric disorders (P < 0.001). They also consumed more alcohol (P = 0.005) and were more often unemployed or unable to work (P < 0.001). In the clinical examination, sleep disturbances, somatic disorders, depression, unemployment, and alcohol use were commonly found in addition to considerable solvent exposure history and clinical neurological findings. Further examinations and a diagnostic follow-up verified three cases of encephalopathy. One case was a CSE, an occupational disease. The other two encephalopathy cases had multifactorial aetiology including solvents.

Screening in active workforce for symptoms of cognitive dysfunction identifies highly solvent-exposed workers and also reveals occupational and non-occupational cases of encephalopathy. Evaluation of differential diagnostic conditions is essential in the detection of CSE. A stepwise model is proposed.