Does age matter? Comparing case fatality rates for selected poisonings reported to U.S. poison centers.

BACKGROUND

As the elderly population continues to grow, the number of geriatric patients reported to poison centers continues to increase. We believe that older poisoned patients are at an increased risk of death compared to younger adult patients. The objective of this study was to compare the risk of death from selected poisoning between younger (<59) and older (>59) adults.

METHODS

We included adult cases reported to U.S. poison centers between 1995 and 2002. To limit potential confounders, our analysis included single substance ingestions of theophylline, digoxin, benzodiazepines, tricyclic antidepressants, calcium channel antagonists, acetaminophen, and salicylate. We determined the case fatality rate for each poisoning for younger and older adults. We calculated crude odds ratios for each poison and then used logistic regression to adjust for covariates.

RESULTS

Overall we found an increase in the relative rate of death for each poison (range 1.2 to 7.1). After adjustment, each 10-year increase in age was associated with a 36% increase in the odds ratio for death as an outcome. Our findings were limited by the use of poison center data, which does not include data on covariates that may be potential confounders.