Underreporting of AIDS deaths in Brazil: linkage of hospital records with death certificate data.

This study investigated the underreporting of deaths due to Acquired Immunodeficiency Syndrome (AIDS) in Brazil, using the product of the linkage between the Mortality Information System (SIM) and the Hospital Information System (SIH) for the years 2008 to 2012. The hypothesis was that there were deaths recorded in the SIM that should have AIDS as the underlying cause of death, but that had been poorly classified. Many of the decedents had previous hospitalizations due to the illness. Underreported AIDS deaths were defined taking into account the coding rules of the International Classification of Diseases 10th Revision, in order to discriminate AIDS deaths from those due to other causes in people living with HIV / AIDS. In this period, 60,362 deceased had AIDS as the underlying cause, and we found another 2,671 (4.2%) as underreported causes. Underreported deaths increased the average AIDS mortality rate from 6.3/100,000 to 6.6/100,000. In conclusion, this study demonstrated that, through linkage in between SIH and SIM, it is possible to find underreporting of AIDS deaths in Brazil. These results serve as a warning for the need for actions that would promote a better certification of the causes of death among AIDS patients.