Impact of COVID-19 on poisoning-related mortality in Iran: An interrupted time series study

The COVID-19 pandemic had many negative effects worldwide. These effects involved mental health status issues such as suicide, depression, and the pattern of death associated with drug/poisonings. One of the major concerns of the healthcare community during the pandemic was mortality from poisonings. This study aimed to investigate the trends of mortality from different types of poisonings before and after COVID-19.

The patients who died from six different categories of drugs or poisons were identified by forensic analysis of body fluids/tissues in Tehran, Iran. The pandemic was separated into the pre-COVID-19 period (April 2018 to January 2020), and the COVID pandemic (February 2020-April 2022). Demographic characteristics were collected from each victim, and comparisons of death trends before and after the pandemic were conducted using the interrupted time series analysis. The absolute number of deaths and proportion of deaths from each type of drug/poisoning were used for the analyses.

A total of 6,316 deaths from drugs/poisoning were identified between April 2018-Mar 2022). During this period, 2,485 deaths occurred pre-COVID, and 3,831 were during the COVID-19 era. There were no statistical differences in terms of demographic characteristics before and after the pandemic, except for job status. There was a sharp increase in proportion of methanol death among all poisonings after the start of the pandemic (16.5%, p-value = 0.025), while there was a decreasing trend during the pandemic (-0.915 deaths monthly, p-value = 0.027). The trends for opioids, stimulants, and drug-related deaths changed from decreasing to increasing. No change was seen in the trends for ethanol and volatile substance deaths. This pattern was mirrored in the proportion of each type of poisoning relative to the total number.

Changes in poisoning-related mortality patterns showed dramatic changes after the start of the pandemic, especially deaths from methanol. Other poisonings such as opioids, stimulants, and drugs should also be addressed as there was an increasing trend during the COVID-19 period, compared to the pre-COVID data.