Carbon monoxide poisoning: a new incidence for an old disease.

PURPOSE While carbon monoxide (CO) poisoning is common in the USA, its incidence is uncertain. Fatal poisonings are counted with relative accuracy from death certificate data, but estimates of the more common nonfatal poisonings are either old or limited. This study was performed to estimate the number of emergency department (ED) visits annually in the USA for carbon monoxide poisoning. BASIC PROCEDURES ED visit rates in five states (Idaho, Maine, Montana, Utah, and Washington) from three prior studies, each using different methodology, were used to extrapolate independent estimates of national ED visits. MAIN FINDINGS After correcting for regional differences in CO poisoning incidence, estimates of national ED visits per year ranging from 32,413 to 56,037 were obtained. Excluding the estimate derived from the Maine rate because it did not include intentional and fire-related poisonings, the national average is 50,558 +/- 4,843 visits per year. CONCLUSIONS There are approximately 50,000 ED visits for CO poisoning in the USA annually, 3-5 times the numbers previously estimated. As this disease can result in significant long-term morbidity even when treated, enhanced prevention efforts are warranted.