A comparative study of mortality among Puerto Rican injection drug users in East Harlem, New York, and Bayamon, Puerto Rico

Drug users have been found to be at high risk of mortality but the mortality experience of Hispanic drug users remains understudied. This study assessed mortality among Puerto Rican injection drug users (IDUs) in New York City (NY), and in Puerto Rico (PR). Study subjects were 637 IDUs from NY and 319 IDUs from PR. Mortality was ascertained using data from the National Death Index. Annual mortality rate of the NY cohort was 1.3 per 100 person years compared to the PR cohort with a rate of 4.8. Compared to the Hispanic population of New York City, the standardized mortality ratio (SMR) of the NY cohort was 4.4. Compared to the population of Puerto Rico, the SMR of the PR cohort was 16.2. The four principal causes of death were: NY-HIV/AIDS (50.0%), drug overdoses (13.3%), cardiovascular conditions (13.3%), and pulmonary conditions (10.0%); PR-HIV/AIDS (37.0%), drug overdoses (24.1%), sepsis (13.0%), and homicide (11.1%). Modeling time to death using Cox proportional hazards regression, the relative risk of mortality of the PR cohort as compared to the NY cohort was 9.2. The other covariates found to be significantly associated with time to death were age, gender, education, social isolation, intoxication with alcohol, and HIV seropositivity. The large disparity in mortality rates found in this study suggests that health disparities research should be expanded to identify intra-group disparities. Furthermore, these results point to an urgent need to reduce excess mortality among IDUs in Puerto Rico.