Page 63 - Contributed Paper Session (CPS) - Volume 3

CPS1944 Oyelola A.
into segments of extreme and moderate cold/heat as well as extreme and
moderate low/high rainfall. The risks associated with temperature (with
o
reference to optimum temperature of 28.8 C) were significantly higher for
o
temperatures lower than 25 C. For example, the cumulative associated risk
o
over the range 0-15 lags weeks at extreme cold (16 C) and moderate cold (20
o C) were 1.83 (95% eCI: 0.88 – 3.78) and 2.28 (95% eCI: 1.94 – 2.68, respectively
(Table 3). The risk were higher for shorter lags and decreases over longer. In
the case of rainfall, 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).
Using backward perspective and the optimum value as references, the
estimated proportions of incidence of pneumonia attributable to temperature
and rainfall are presented in Table 4. The total attributable fraction due to
temperature is 28.4% (95% eCI: 19.7 – 36.2). Taken separately, the total fraction
of cases attributed to varying temperature is predominantly due to moderate
temperatures (27.0%, 95% eCI: 17.8 – 34.8) against extreme heat (0.07%, 95%
eCI: -0.4 – 0.6) (Table 4). The overall proportion of cases attributable to rainfall
is higher than attributable to temperature however, not significant (28.4%,
95% eCI: 19.7 – 36.2 vs. 50.8%, 95% eCI: -6.4 – 76.5). Most pneumonia cases
attributable to rainfall occurred during moderate rainfall (18.4%, 95% eCI: 8.5
– 26.4).
Differences were observed in the associated risk of pneumonia and varying
temperatures and rainfall among different groups. For example, looking at
specific estimated risk associated with 15 weeks cumulative exposure of 20 C
o
temperature, we observed; increased relative risk of pneumonia in females
(RR=2.90, 95% CI: 2.31 – 3.64) compared to males (RR=1.87, 95% CI: 1.52 –
2.30), among indigenous (RR=2.55, 95% CI: 1.82 – 3.57) vs. non-indigenous
(RR=2.22, 95% CI: 1.86 – 2.65); emergency admission (RR=2.44, 95% CI: 2.01
– 2.95) vs. others (RR=1.96, 95% CI: 1.45 – 2.66) and older patients aged >14
years (RR=2.29, 95% CI: 1.43 – 3.65) against RR=2.62 (95% CI:1.99 – 3.43) for
14 years and less. Similarly, the pneumonia-rainfall associated risk of exposure
to a total weekly rainfall of 40 mm (at the end of 15 weeks) is higher for females
(RR=6.27, 95% CI: 1.87 – 21.12) than males (RR=4.84, 95% CI: 1.54 – 15.07),
higher among indigenous (RR=6.75, 95% CI: 1.08 – 42.36) vs. non-indigenous
(RR=4.81, 95% CI: 1.99 – 13.64); lower for emergency admission (RR=4.82, 95%
CI: 1.71 – 13.54) vs. others (RR=7.41, 95% CI: 1.36 – 40.28 and lower for older
patients aged >14 years (RR=5.89, 95% CI: 1.40 – 24.78) against RR=11.36
(95% CI: 0.67 – 190.73) for 14 years and less.

4. Discussion and Conclusion
The 2015 global burden of disease revealed that lower respiratory tract
infections is the fifth leading cause of death worldwide[21]. Among these,

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