Page 57 - Contributed Paper Session (CPS) - Volume 3

CPS1944 Oyelola A.

Time-lagged variables and incidence of
pneumonia in wet-dry tropical North Australia
1*
1, 2
1
Oyelola Adegboye , Emma McBryde , Damon Eisen
1 Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, QLD
2 Townsville Hospital and Health Service, QLD

Abstract
Few studies have focused on incidence of pneumonia in relation to time-
lagged variables. We investigated the attributable risk of pneumonia
associated with time-lagged weather variables in wet-dry tropics of Australia.
We used distributed lag nonlinear models to estimate the relative risk
associated with prolong exposure to weather conditions based on data from
large cohort of patients hospitalized due to pneumonia between 2006 and
2016 North Queensland. The disease was identified using the International
Statistical Classification of Diseases and Related Health Problems, Tenth
Revision, Australian Modification (ICD10-AM) code J10.0* - J18. The risks
associated with temperature were immediate and higher at moderate low (20
o C) temperature (RR=2.28, 95% eCI: 1.94 – 2.68). The cumulative effect over
lag range 0 – 15 lag weeks revealed higher risk at moderate low rainfall (40
mm) with RR=5.49 (95% eCI: 2.27 – 13.24). About one-third, 28.4% (95% eCI:
19.7 – 36.2) of pneumonia cases were attributable to temperature (mostly due
to moderate temperatures) while the overall proportion of cases attributable
to rainfall (50.8%, 95% eCI: -6.4 – 76.5) was higher than attributable to
temperature however, not significant. The findings in this study can inform a
better understanding of the health implications and burden associated with
pneumonia to support discussion-making in healthcare and establish a
strategy for prevention and control of the disease among vulnerable groups.

Keywords
Wet-dry tropics; Pneumonia; Lagged variables; Temperature; Rainfall

1. Introduction
Lower respiratory infections accounted for about 40% of the total
infectious disease burden in 2011 in Australia [1]. Australian hospital statistics
revealed that about 4.3% of total primary diagnosis during the period 2012-
2013 were classified as disease of respiratory system [2]. Potentially
preventable hospitalization (PPH) accounts for 8.2% of all hospital admissions
during the same period, of which 0.3% were vaccine preventable [2].
Queensland has second largest burden of PPH preceded by Northern Territory
(17.2% vs. 23.2%) in Australia, one-third of which were vaccine preventable
influenza and pneumonia [2].
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