ABSTRACT
Objective@#To study the lag effect of temperature and the source of heterogeneity on other infectious diarrhea (OID) in Zhejiang province, so as to identify related vulnerable populations at risk.@*Methods@#Data on OID and meteorology in Zhejiang province from 2014 to 2016 were collected. A two-stage model was conducted, including: 1) using the distributed lag non-linear model to estimate the city-specific lag effect of temperature on OID, 2) applying the multivariate Meta- analysis to pool the estimated city-specific effect, 3) using the multivariate Meta-regression to explore the sources of heterogeneity.@*Results@#There were 301 593 cases of OID in Zhejiang province during the study period. At the provincial level, temperature that corresponding to the lowest risk of OID was 16.7 ℃, and the temperature corresponding to the highest risk was 6.2℃ (RR=2.298, 95%CI: 1.527- 3.459). 16.7 ℃ was recognized as the reference temperature. P5 and P95 of the average daily temperature represented low and high temperature respectively. When the temperature was cold, the risk was delayed by 2 days, with the highest risk found on the 5th day (RR=1.057, 95%CI: 1.030-1.084) before decreasing to the 23rd day. When the temperature got hot, the risk of OID occurred on the first day (RR=1.081, 95%CI: 1.045-1.118) and gradually decreasing to the 8th day. Differences on heterogeneous sources related to the risks of OID in different regions, presented on urban latitude and the rate of ageing in the population.@*Conclusions@#Both high or low temperature could increase the risk of OID, with a lag effect noticed. Prevention program on OID should be focusing on populations living in the high latitude and the elderly population at the low temperature areas.
ABSTRACT
Objective To understand the influence of diurnal temperature range (DTR) on influenza incidence in the elderly in Beijing and to conduct a subgroup analysis.Methods The incidence data of daily influenza cases in the elderly and daily meteorological data from 2014 to 2016 in Beijing were collected for this study.A generalized additive model (GAM) was used to explore whether the relationship between daily influenza cases and DTR is a linear one.A distributed lag non-linear model (DLNM) was established to quantify the lagged effect of DTR on daily influenza incidence in the elderly.The model was also used to estimate the effects of DTR on daily influenza incidence among various subgroups.Results A total of 4 097 influenza cases in the elderly were notified during study period.The mean DTR was 10.153 ℃.A linear relationship between daily influenza incidence and DTR was detected by using GAM.DTR was significantly associated with daily influenza incidence between lag0 and lag5 with a maximal effect at lag0.An 1 ℃ increase of DTR was associated with a 2.0％ increase in daily influenza incidence in the elderly (95％CI:0.9％-3.0％).The RR values of males,females,people aged 60-69 years,people aged ≥70 years were 1.018 (95％CI:1.005-1.032),1.021(95％CI:1.007-1.035),1.012 (95％CI:1.002-1.022),1.025 (95％CI:1.012-1.039),respectively.The influencing time of DTR on females (lag6) was longer than males (lag2).Conclusions DTR was associated with increased risk of influenza in the elderly in Beijing.It is necessary to take targeted measures in the elderly to control the incidence of influenza when DTR becomes greater.
ABSTRACT
Objective To understand the influence of diurnal temperature range (DTR) on influenza incidence in the elderly in Beijing and to conduct a subgroup analysis.Methods The incidence data of daily influenza cases in the elderly and daily meteorological data from 2014 to 2016 in Beijing were collected for this study.A generalized additive model (GAM) was used to explore whether the relationship between daily influenza cases and DTR is a linear one.A distributed lag non-linear model (DLNM) was established to quantify the lagged effect of DTR on daily influenza incidence in the elderly.The model was also used to estimate the effects of DTR on daily influenza incidence among various subgroups.Results A total of 4 097 influenza cases in the elderly were notified during study period.The mean DTR was 10.153 ℃.A linear relationship between daily influenza incidence and DTR was detected by using GAM.DTR was significantly associated with daily influenza incidence between lag0 and lag5 with a maximal effect at lag0.An 1 ℃ increase of DTR was associated with a 2.0％ increase in daily influenza incidence in the elderly (95％CI:0.9％-3.0％).The RR values of males,females,people aged 60-69 years,people aged ≥70 years were 1.018 (95％CI:1.005-1.032),1.021(95％CI:1.007-1.035),1.012 (95％CI:1.002-1.022),1.025 (95％CI:1.012-1.039),respectively.The influencing time of DTR on females (lag6) was longer than males (lag2).Conclusions DTR was associated with increased risk of influenza in the elderly in Beijing.It is necessary to take targeted measures in the elderly to control the incidence of influenza when DTR becomes greater.