Is There a Weather Seasonal Effect on Acute Pancreatitis Etiology and Outcomes?

Abstract

Introduction: Approximately 20% of Acute pancreatitis (AP) cases are deemed to be idiopathic. Gallstone disease has been reported to have increased incidence during summer and this could be due to variations in temperature during these months. The aim of this study was to identify the prevalence of different AP etiologies during the weather seasons and to investigate the association between temperature variation, seasonal effect and the onset of acute pancreatitis, its severity and outcomes. Methods: We performed a retrospective cohort study of consecutive patients admitted with a very first episode of acute pancreatitis at a large public hospital in Chicago between 01/2013 and 12/2014. We identified acute pancreatitis diagnosis by ICD9 code and/or lipase ≥ 3 times the normal upper limit. Two physicians reviewed each case to include only first episodes of acute pancreatitis. We excluded patients who were transferred to our center. We included a detailed weather season history and temperature in Celsius degree on the day of admission for each AP case from the publically available website: weather. com. We constructed multivariable logistic regression models. Results: We analyzed 460 patients. Mean age was 48 years (range 17 to 89 years), 54% were males. In Univariate and Multivariate analysis, having an AP episode during winter was found to be protective against Acute Kidney Injury (AKI) (aOR: 0.4, P<0.005, CI 0.2-0.9). After adjusting for admission SIRS, age and gender; Weather seasons were found to impact AP etiology nor be independent risk factors for Persistent Systemic Inflammatory Response Syndrome (SIRS), AKI, ARDS, pancreatic necrosis, mortality, ICU, Length of Stay (LOS), in-hospital infections, BISAP score, nor recurrent AP. In addition, the mean temperature (T) of Chicago (15°C) was compare to lower temperatures as well as higher temperature variations; Higher temperatures than the average Chicago T was found to be protective against Persistent SIRS at 48h (aOR 0.6, P<0.05, CI 0.3-0.9). No other significant impact on these temperatures variations was found. Conclusion: Weather Seasonal effect was not found to impact the etiology of acute pancreatitis. All etiologies were equally distributed among all seasons. However, AKI during winter was found to have a significantly lower incidence and Persistent SIRS had lower incidence during higher or warmer temperatures. This is the largest study to date to examining weather seasonal effect in AP.