Increased suicidal risk among smoking schizophrenia patients

Schizophrenia patients display a high suicidal risk, although this risk is difficult to predict. One of the variables associated with increased suicide risk is smoking. In the present study, we assessed the suicidal risk in schizophrenia patients, smokers and nonsmokers. We also evaluated the impact of various variables such as psychotic symptoms, impulsivity, and extra-pyramidal side effects on suicidal risk.

Sixty-one schizophrenia patients responded to a battery of measures, including the suicidal risk scale (SRS), the positive and negative syndrome scale (PANSS), the impulsivity control scale, and the Simpson Angus Scale for extrapyramidal side effects. The effect of smoking on the various measures, especially suicidal risk, was examined.

Schizophrenia patients who smoke obtained higher PANSS scores (both total score and positive and negative subscales), but did not differ on the Simpson Angus scale of extrapyramidal side effects. They also exhibited higher suicide risk as reflected by higher scores on the SRS, and a trend for higher impulsivity as measured by the impulsivity control scale. Women that smoked had higher SRS scores as compared with female nonsmokers, and also higher than in males, smokers and nonsmokers. Smoking and a history of suicide attempt predicted in our regression analysis a higher SRS score. When conducting separate analyses for the male and female patients, the significant contributors were the PANSS total score among the males and the number of pack-years among the female patients.

Despite hints toward the role of smoking in suicidal behavior in Schizophrenia, especially among female patients, more studies are needed to elucidate the association between smoking and suicidality in schizophrenia patients.