Distinct acute and delayed effects of temperature and atmospheric pressure on allergic rhinitis: a distributed lag non-linear time-series study in subtropical China
Jul 2026· Frontiers in Public Health· Vol 14· 0 citations· 26 references
Medicine
TL;DR
Higher temperature was consistently associated with rapid increases in AR outpatient visits in this humid subtropical population, providing epidemiological evidence for climate-sensitive AR prevention and support the incorporation of meteorological indicators into seasonal surveillance, early warning systems, and healthcare resource planning.
Abstract
Background Meteorological conditions are increasingly recognized as important determinants of allergic diseases; however, their temporal dynamics and delayed effects on allergic rhinitis (AR) remain inadequately characterized, particularly in subtropical settings. This study aimed to examine the non-linear and lagged relationships between major meteorological variables and AR-related outpatient visits in Wuxi, a representative subtropical city in eastern China. Methods A time-series analysis was conducted using data from 76,760 AR outpatient visits recorded in Wuxi, China, between November 2020 and December 2024. Daily meteorological variables, including mean temperature, atmospheric pressure, relative humidity, wind speed, and air pollution indicators were obtained from local monitoring stations. Distributed lag non-linear models (DLNM), coupled with quasi-Poisson regression, were employed to estimate exposure–response relationships and lagged effects, with adjustment for long-term trends, seasonality, and day-of-week effects. Results AR outpatient visits showed clear seasonal variation, with a major autumn peak and a secondary spring peak, and were predominantly concentrated among children and younger adults. Daily mean temperature was positively and non-linearly associated with AR outpatient visits, with risk increasing progressively above approximately 15 °C. Compared with 15 °C, the cumulative relative risk reached 1.19 at 25 °C and 1.41 at 30 °C, and the association was mainly acute, peaking within lag 0–3 days. In the primary single-exposure DLNM, lower atmospheric pressure showed an inverse exposure–response pattern and a delayed lag structure, with the strongest association observed around lag 8–10 days. However, pressure-related estimates were less stable in co-meteorological-adjusted and age-stratified analyses, suggesting that low atmospheric pressure may reflect broader synoptic weather conditions rather than an isolated independent exposure. Relative humidity and wind speed showed no robust independent associations. Conclusion In this humid subtropical population, higher temperature was consistently associated with rapid increases in AR outpatient visits. Lower atmospheric pressure showed a delayed association in the primary model, but this pattern was less robust after accounting for correlated meteorological variables and across age strata. These findings provide epidemiological evidence for climate-sensitive AR prevention and support the incorporation of meteorological indicators into seasonal surveillance, early warning systems, and healthcare resource planning.
This study aims to quantify the short-term association between ambient air pollutants and outpatient visits for conjunctivitis using empirical data. Methods: This study collected daily outpatient visits for conjunctivitis in Jiayuguan City from January 1, 2023 to December 31, 2024, as well as meteorological and air pollutant data during the same period. We used a quasi-Poisson generalized linear regression model that incorporates a distributed lag nonlinear model to analyze the nonlinear relationship and lag effect between pollutant exposure and the risk of outpatient visits for conjunctivitis, and conducted stratified analysis by gender, age and season to identify susceptible populations. Results: A total of 14,598 cases of conjunctivitis were included during the study. The results showed that particulate matter (PM
2.5
and PM
10
) was not statistically significantly associated with outpatients for conjunctivitis, and the exposure-response curve showed a downward trend. Conversely, gaseous pollutants (NO
2
and CO) showed a significant positive linear correlation with outpatients for conjunctivitis, with the effect being stronger in the cold season. NO
2
was significant at lag1-3, lag5 days and lag02–07 days, with each 10 µg/m
3
increase corresponding to an RR of 1.126 (95% CI 1.050, 1.208), corresponding to a 12.60% increase in patient visits. CO had the strongest effect at lag07 days (RR = 1.836, 95% CI 1.126, 2.991). Furthermore, NO
2
primarily increases conjunctivitis visits in women and children (0–14 years), while CO exposure is significantly associated with conjunctivitis visits in men and older adults (≥ 65 years). Conclusions: In this arid, industrial city in Northwest China, gaseous pollutants (rather than particulate matter) are the key environmental factor driving the increase in conjunctivitis outpatient visits. This study reveals the differentiated effects of specific pollutants on populations with different demographic characteristics, highlighting the public health significance of strengthening ocular surface health protection for specific vulnerable subgroups during the cold season.
Yanan Zhang, Guorui Song, Bo Zheng et al.· Aerosol and Air Quality Rese...· 0 citations
High temperature and high relative humidity were associated with increased daily outpatient visits for HA in Guangzhou, whereas low temperature and lower relative humidity were associated with fewer visits in the main model.
Fei-Fei Yan, Rong Xu, Yi Dong et al.· Frontiers in Pediatrics· 0 citations
Hand, foot and mouth disease (HFMD) is a sudden infectious illness commonly seen in children under 5 years old. It has been reported that meteorological factors, particularly the temperature, influence the transmission of HFMD. However, the connection between the temperature effect and social contact patterns has not been clearly established yet. The occurrence of COVID-19 provided an accidental opportunity to investigate this problem.
We studied 36,648 hand, foot and mouth disease (HFMD) cases in Liangjiang New Area, Chongqing, China from January 1, 2020 to December 31, 2024, combined with daily meteorological information (temperature, atmospheric pressure, wind speed and diurnal temperature range). A distributed lag non-linear model (DLNM) with a quasi-Poisson link was applied to investigate the relationship between temperature and HFMD. The population attributable fractions (PAF) were calculated using a lag-0 method. Stratified analyses were carried out according to different periods: the period of lockdown (2020), the period with partial controls (2021–2022) and the post-control period (2023–2024). Four sets of sensitivity analyses were conducted to examine the model’s stability.
The full model (including the four meteorological factors) has the minimum QAIC value. There is a J-shaped correlation between the temperature and the risk of HFMD, with the minimum incidence temperature at −10.2 °C and slight rising effects. The total attributable fraction caused by the temperature is 4.99% (including 1,828 cases). The attributable fractions vary with different years: 0.48% in 2020 when the lockdown was enforced, 4.53–4.52% during partial controls and 6.57–5.87% after the lockdown (the average fraction from 2023 to 2024 is 6.33%). The attributable fractions of wind speed (PAF 1.67%) and atmospheric pressure (PAF 1.10%) are relatively small. Sensitivity analyses show that the results are similar to those under different time trends, lag periods, seasonal subsets and covariate settings.
The temperature accounts for about one twentieth of the HFMD cases under usual social interactions, however, this influence is almost disappeared during the COVID-19 lockdown when children are separated. The results indicate that the temperature mainly serves as a permissive behavioral factor promoting child-to-child contacts - rather than acting directly on the viral kinetics. For the control of HFMD, the efforts should focus on improving the hygiene of kindergartens, isolating the cases and vaccinating, instead of monitoring the temperature, although temperature-related preparation according to the seasons is still significant.
Yi Ren, Lan Luo, Shui-Xing Luo et al.· Frontiers in Public Health· 0 citations
This study quantifies humid-heat-related OID risks and investigates the socioeconomic determinants driving spatial vulnerability in Anhui, China, highlighting an “adaptation deficit” in less-developed regions.
Mengyuan Gao, Jinling Song, Jing Wu et al.· BMC Public Health· 0 citations
Short-term exposure to PM2.5, PM10, SO2, NO2, and CO was associated with increased AECOPD hospitalization risk, with nonlinear, lagged, and cumulative effects, and older adults and females may be more susceptible to ambient air pollution.
Huixia Shi, Jiajun Li, Bo-Yan Li et al.· Medicine· 0 citations
The relationship between meteorological factors and influenza seasonality is well-established in temperate regions but remains complex and less understood in subtropical climates. This study investigates the association between key weather variables and influenza-like illness (ILI) incidence in Taiwan using real observational data from 2020 to 2025. We conducted a retrospective ecological study using publicly available data from the Taiwan Centers for Disease Control and the Central Weather Administration. Based on 4,642 complete county-week observations across 17 counties/cities, we examined four meteorological factors: temperature, relative humidity, atmospheric pressure, and precipitation. We found that relative humidity showed the strongest negative correlation with ILI incidence (r = −0.147, p < 0.001; Spearman ρ = −0.196, p < 0.001), followed by atmospheric pressure (r = −0.096, p < 0.001). Temperature and precipitation did not show statistically significant Pearson correlations (r = +0.007, p = 0.625; r = +0.020, p = 0.175, respectively). Stratified analysis across five geographic regions revealed marked heterogeneity: relative humidity was most strongly negatively correlated with ILI in Northern Taiwan (r = −0.223, p < 0.001, n = 1,095) and Central Taiwan (r = −0.196, p < 0.001, n = 934), weakly negatively associated in Southern Taiwan (r = −0.072, p = 0.032, n = 898), and paradoxically positively correlated in Eastern Taiwan (r = +0.089, p = 0.012, n = 790) and the Outlying Islands (r = +0.144, p < 0.001, n = 925). The multiple regression model including all four meteorological variables yielded R2 = 0.045, indicating that these factors collectively explain only 4.5% of the variance in ILI incidence. In Taiwan's subtropical climate, relative humidity is the most consistent meteorological predictor of influenza activity, yet its effect is geographically heterogeneous and even reverses direction in eastern and island regions. These findings underscore the need for region-specific analysis when investigating meteorological drivers of influenza in subtropical settings.
