Underreporting of fatal poisonings in Brazil - A descriptive study using data from four information systems.

Poisoning is a worldwide problem that involves individuals of all ages and a range of chemicals. In this study, fatal poisoning cases that occurred in the Federal District of Brazil (DF) from 2009 to 2013 were described using information from four systems, and the reasons for underreporting of each system were discussed. Data were obtained from the mortality information system (SIM), the notifiable disease information system (SINAN), the poison information center (CIT), and the forensic medicine institute (IML) of the DF. In total, 288 cases were reported to SIM, 18 to SINAN, 29 to CIT and 101 cases identified in the IML. SIM data indicated a prevalence of 2.24 cases/year/100,000 individuals in the DF, higher than the national estimation (1.36). After eliminating the 98 duplicate cases among the systems, 338 fatal unique cases were identified, from which 74.0% were reported in only one system (mainly the SIM), 23.4% in two systems, 8 cases in three systems and only 1 case was reported in the four systems. Over two thirds of the 338 fatalities involved men (67.4%), and 46.9% involved individuals aged 20-39 years. Medications were the main agent involved (49.4%), followed by pesticides (29.9%). The fatalities occurred mainly after unintentional exposure (50.8%) and suicide (47.7%, of which 53.5% involved pesticides). These results confirmed the previous hypothesis that none of the information systems could capture the whole picture of fatal poisonings in the DF. Underreporting was found in all systems, indicating the need to improve the information quality and the coordination of data reporting, so that health authorities can better understand and reduce these fatalities.