To examine the association between age at onset of deafness and mortality. The authors analyzed National Health Interview Survey data from 1990 and 1991--the years the Hearing Supplement was administered--linked with National Death Index data for 1990-1995. Adjusting for sociodemographic variables and health status, the authors compared the mortality of three groups of adults ages > or = 19 years: those with prelingual onset of deafness (< or = age 3 years), those with postlingual onset of deafness (> age 3 years), and a representative sample of the general population. Multivariate analyses adjusted for sociodemographics and stratified by age found that adults with postlingual onset of deafness were more likely to die in the given time frames than non-deaf adults. However, when analyses were also adjusted for health status, there was no difference between adults with postlingual onset of deafness and a control group of non-deaf adults. No differences in mortality were found between adults with prelingual onset of deafness and non-deaf adults. Adults with postlingual onset of deafness appear to have higher mortality than non-deaf adults, which may be attributable to their lower self-reported health status.