Psychiatric comorbidities in patients with intentional methanol intoxication.

Background: Intentional methanol intoxication (IMI) is an emerging public health issue in Asian countries, but few data are available in the literature on underlying psychiatric comorbidities in these suicide attempters.

Patients and methods: We conducted a retrospective chart review on patients with methanol intoxication (MI) treated at Chang-Gung Memorial Hospital, Linkou, Taiwan during 2000-2016. Of the 56 cases of documented MI, 16 were IMI. Baseline demographic, clinical, laboratory, psychiatric diagnoses, and mortality data were collected and analyzed.

Results: Patient group with IMI had more females (62.5% vs 7.5%, P =0.000), less alcohol consumption (33.3% vs 92.5%, P =0.000), and less smoking (40.0% vs 79.5%, P =0.009), but higher past psychiatric disease (73.3% vs 10.0%, P =0.000) and past suicide attempts (81.1% vs 2.5%, P =0.000) than patient group with unintentional MI (UMI). Pesticides (50.0%) comprised the most common source used for suicide, followed by industrial methanol (37.5%). There was no significant difference in mortality rates between these two group (25.0% vs 22.5%, P =0.548). Twelve (75.0%) survivors of IMI were referred to a psychiatric consultation-liaison team, and depressive disorder (58.3%) and adjustment disorder (25.0%) were common.

Conclusion: There is a female predominance and a high prevalence of psychiatric comorbidities, namely depression and adjustment disorder in patients with IMI. Besides, alcohol consumption is a prevalent but not adequately treated condition in UMI group.