%0 Journal Article
%T Is there a clinically significant seasonal component to hospital admissions for atrial fibrillation?
%A Ross EG Upshur
%A Rahim Moineddin
%A Eric J Crighton
%A Muhammad Mamdani
%J BMC Health Services Research
%D 2004
%I BioMed Central
%R 10.1186/1472-6963-4-5
%X We conducted a retrospective population cohort study using time series analysis to evaluate seasonal patterns of atrial fibrillation hospitalizations for the province of Ontario for the years 1988 to 2001. Five different series methods were used to analyze the data, including spectral analysis, X11, R-Squared, autocorrelation function and monthly aggregation.This study found evidence of weak seasonality, most apparent at aggregate levels including both ages and sexes. There was dramatic increase in hospitalizations for atrial fibrillation over the years studied and an age dependent increase in rates per 100,000. Overall, the magnitude of seasonal difference between peak and trough months is in the order of 1.4 admissions per 100,000 population. The peaks for hospitalizations were predominantly in April, and the troughs in August.Our study confirms statistical evidence of seasonality for atrial fibrillation hospitalizations. This effect is small in absolute terms and likely not significant for policy or etiological research purposes.Atrial fibrillation is the most common cardiac arrhythmia in the elderly population requiring medical treatment. The prevalence of this disease is clearly related to age and can be as high as 15 to 18% after the age of 80 [1,2]. The seasonality of hospitalizations for atrial fibrillation has been the focus of epidemiological study as seasonality is a potential clue to etiology. Recent studies examining the seasonality of atrial fibrillation using monthly aggregations of emergency reports over a 10-year period in one study, and emergency room visits over a 1-year period in another, both found statistically significant seasonal differences in monthly values, with peaks typically occurring in the winter and troughs in the summer [3,4]. Frost et al in a study of hospitalizations for atrial fibrillation in Denmark found a winter peak and summer trough, with a small but statistically significant relative risk of 1.20 (95% confidence interval: 1
%K Atrial fibrillation
%K seasons
%K stochastic processes
%K statistics
%K time factors
%U http://www.biomedcentral.com/1472-6963/4/5