title: Calendar patterns in the occurrence of cardiac arrest.
abstract: Our objective was to determine whether monthly and daily patterns existed in cardiac arrests in a 7 emergency department (ED) cohorts in New Jersey. We conducted a retrospective analysis of a computerized database over an 11-year period containing 2,370,233 patient visits and 6,827 nontraumatic cardiac arrests. Time-series regression revealed colder months having more cardiac arrests, especially for patients >or=65 years of age. In that age group, December and March were highest with 17% more (P =.002) than the average of nonsignificant months. August was the lowest with 19% (P =.001) fewer cardiac arrests. Day-of-week variation was found only for patients <65 years of age. Saturdays and Mondays had more arrests than nonsignificant days, 15% (P <.0001) and 9% (P =.01), respectively. We conclude that there are monthly and daily patterns in cardiac arrests, with more arrests in the colder months for those >or=65 years of age, and more for ages <65 on Saturdays and Mondays.
mesh_terms: D000367:Age Factors; D000368:Aged; D002940:Circadian Rhythm / Q000502:physiology; D015331:Cohort Studies; D004632:Emergency Medical Services; D006323:Heart Arrest / Q000453:epidemiology* / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D009515:New Jersey / Q000453:epidemiology; D012044:Regression Analysis; D012189:Retrospective Studies; D012621:Seasons; D018881:Suburban Health; D013997:Time Factors; D014504:Urban Health