Comparison of Cotinine Excretion in Schizophrenics and Normal Controls

Jeong, Il Jin; Choi, Yu Man; Lee, Hee Jeong; Chung, Moon Young

Abstract

OBJECTIVES
The prevalence of smoking in schizophrenic patients (74-92%) is higher than that of all psychiatric patients (34-54%) or general population (30-35%). This higher smoking Prevalence is demonstrated even after controlling for known confounders, such as marital status, alcohol use, and socioeconomic status. This study was conducted to determine whether there would be any difference in nicotine intake and metabolism between schizophrenics and normal controls.
METHODS
Sixteen schizophrenic patients and sixteen normal controls were collected. All subjects were supplied with a pack of cigarette a day. Urinary cotinine excretion was measured by using gas chromatographic mass spectrometric method.
RESULTS
Cotinine excretion was significantly increased in schizophrenic patients compared to normal controls (p<0.05). None of variables such as age at initial smoking, the average number of cigarettes at initial smoking, pack year (packs daily smoked x smoking year), abstinence history were found to influence cotinine levels when examined via the ANOVA, even when the interaction with diagnosis was considered.
CONCLUSION
This result suggests that nicotine intake and consumption are increased in schizophrenic patients compared to normal controls, which can be an attempt to improve sensory inhibition and counteract neuronal effect of antipsychotic medications.