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A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data
Published on: December 9, 2015
[Seasonal changes in morbimortality caused by pulmonary thromboembolism in Galicia]
J Montes Santiago1, G Rey García, A Mediero Domínguez
1Servicio de Medicina Interna, Hospital Meixoeiro, Vigo, Pontevedra. julio.montes.santiago@sergas.cs
Objectives:
The goal of this report was to analyze the seasonal variation in the pulmonary embolism (EP) hospitalizations and mortality at the hospitals of the Galician Service of Health (SERGAS) in the Northwest of Spain, during the period 1996-2001.
Methods:
The Related Group of Diagnosis (DRG) 78 (pulmonary embolism) from the SERGAS hospital discharge dataset during the 6-year period was examined. Age, sex, month of discharge and seasonal period was annotated.
Results:
A total of 2831 hospitalizations for TEP were recorded (44% males, mean inhospital stay: 12.8 days, 70% > 65 years). Monthly median was 38 discharges and the variations above and below this were +26% (December) and -25%) (July), respectively. There were more frequents hospitalizations in autumn (OR:1.35, 95%CI:1.19-1.53) and winter (OR: 1.29, CI: 1.14-1.46). Mortality peaked in spring (OR:2.18, CI: 1.18-4.05). Nearly 83% of these deaths occurred in persons > 75 years old.
Conclusions:
We observed a marked increase in EP hospitalizations during colder months and in mortality during spring. These observations may have implications in the adoption of preventive measures.
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