Interstitial Lung Disease: Seasonality of Hospitalizations and In-Hospital Mortality 2005–2015

Abstract

<b><i>Background:</i></b> The overall incidence of interstitial lung disease and disease-associated mortality have been found on the rise. Hospitalizations for interstitial lung disease are typically caused by airway infection or the acute exacerbation of the underlying disease. Seasonal variance in ambient air pollution has recently been linked to exacerbation and mortality. We sought to examine the seasonal pattern of hospitalizations in Germany, use of mechanical ventilation, and in-hospital mortality on a year-by-year basis to identify their overall trend and to characterize seasonal patterns. <b><i>Methods:</i></b> The national in-patient database of the federal statistical office of Germany was searched for cases of interstitial lung disease. <b><i>Results:</i></b> A total of 130,366 hospitalizations for ILD occurred from 2005 to 2015. Time series data were examined for seasonality using X-11 statistics. The incidence of hospitalizations, mechanical ventilation, and in-hospital mortality show clear seasonal peaks in the cold season. The observed seasonality cannot be attributed to the variance of selected comorbidities. Also, there is a significant overall upward trend regarding hospitalization counts, especially in the use of non-invasive ventilation. <b><i>Conclusion:</i></b> Time series analysis of in-hospital data shows an ILD-related rise of hospitalizations, in-hospital mortality, and non-invasive ventilation. This emphasizes a growing importance of interstitial lung diseases for health-care systems. Strong seasonality is seen in these variables. Data therefore support previous studies of ILD exacerbation. More research on infectious causes and environmental factors is warranted.

The increasing trend and seasonal variation in attendance in patients with interstitial lung disease

“…The seasonal variation in hospitalization and mortality has been attributed to a rise in ambient air pollution, viral infections driving acute exacerbations of ILD, and autoimmune disease activity during the winter period. [ 4 ]…”

Effects of Influenza Vaccination in Patients with Interstitial Lung Diseases: An Epidemiological Claims Data Analysis

“…Information on influenza in patients with ILD is scarce. However, a seasonality in hospitalizations and mortality in ILD was reported, with peaks in the winter, which might be related to the influenza season ( 6 , 7 ). The most effective protection is vaccination ( 8 ).…”