BACKGROUND: Genetic and environmental factors affect the occurrence of vaso-occlusive crises (VOCs) in patients with sickle cell disease (SCD). Research provides inconsistent evidence on how environmental temperature affects SCD. Edmonton, Alberta, has an increasing SCD population and is the northern-most city in North America with a population of over a million. OBJECTIVE: The objective of this study was to identify whether pediatric patients with SCD experience increased morbidity in cold external temperatures. MATERIALS AND METHODS: This study was a retrospective case series. Emergency visits, phone calls, and admission data for VOC in children were recorded from July 2011 to June 2016. Temperatures were recorded and statistically analyzed using descriptive statistics, to determine the relation to VOC. RESULTS: A total of 118 patients with 257 VOC events were reviewed. When analyzing the mean, minimum, and change in temperatures at presentation, the largest percentage of VOC events occurred at mild to moderate temperatures. Temperature data at 24 and 48 hours before the presentation had similar results. When accounting for the relative frequency of extreme weather days, there are increased VOC events with temperature fluctuations >20°C. CONCLUSIONS: There was no correlation between mean and minimum temperature change. Fluctuation in temperature of >20°C was associated with increased relative VOC frequency, suggesting that large temperature variability should be avoided in SCD, but a prospective study is required to determine causality.
BACKGROUND: Genetic and environmental factors affect the occurrence of vaso-occlusive crises (VOCs) in patients with sickle cell disease (SCD). Research provides inconsistent evidence on how environmental temperature affects SCD. Edmonton, Alberta, has an increasing SCD population and is the northern-most city in North America with a population of over a million. OBJECTIVE: The objective of this study was to identify whether pediatric patients with SCD experience increased morbidity in cold external temperatures. MATERIALS AND METHODS: This study was a retrospective case series. Emergency visits, phone calls, and admission data for VOC in children were recorded from July 2011 to June 2016. Temperatures were recorded and statistically analyzed using descriptive statistics, to determine the relation to VOC. RESULTS: A total of 118 patients with 257 VOC events were reviewed. When analyzing the mean, minimum, and change in temperatures at presentation, the largest percentage of VOC events occurred at mild to moderate temperatures. Temperature data at 24 and 48 hours before the presentation had similar results. When accounting for the relative frequency of extreme weather days, there are increased VOC events with temperature fluctuations >20°C. CONCLUSIONS: There was no correlation between mean and minimum temperature change. Fluctuation in temperature of >20°C was associated with increased relative VOC frequency, suggesting that large temperature variability should be avoided in SCD, but a prospective study is required to determine causality.