Impact of meteorological conditions and air pollution on the incidence of carbon monoxide poisoning: a retrospective analysis in northern China.

BACKGROUND

Carbon monoxide (CO) poisoning remains a critical public health issue, particularly in residential settings during colder months when heating practices can lead to indoor CO accumulation. The relationship between meteorological conditions, air pollutants, and CO poisoning remains poorly understood. This study aims to investigate the impact of weather factors and air pollution on the incidence of CO poisoning, with a focus on identifying risk factors associated with severe outcomes such as coma.

METHODS

We conducted a retrospective study of CO poisoning cases in a northern Chinese urban area, categorizing patients into coma and non-coma groups. We analyzed clinical characteristics, including age, gender, comorbidities, time of hospital admission, and severity of poisoning. Meteorological data, including temperature, relative humidity, wind speed, and 24-hour temperature changes, as well as air quality indices (AQI), concentrations of CO, NO₂, SO₂, O₃, PM2.5, and PM10, were collected and analyzed for their correlation with CO poisoning incidence.

RESULTS

The investigation revealed significant correlations between CO poisoning and patient characteristics and environmental factors. Notably, patients in the coma group were significantly older (P = 0.003) and predominantly presented at the hospital between 6:00 AM and 11:59 AM. Atmospheric CO concentration emerged as a critical risk factor, demonstrating nearly a twofold increase in poisoning risk per 1 mg/m³ increment (OR = 2.001, 95% CI: 1.105-3.622). Meteorological parameters exhibited complex interactions with poisoning susceptibility: mean temperature showed a pronounced protective effect (OR = 0.893, 95% CI: 0.873-0.914, P < 0.001), with each unit decrease corresponding to a 10.7% increase in risk. Temperature dynamics further amplified this risk, with 24-hour temperature fluctuations significantly increasing poisoning susceptibility by 25.7% per unit change (OR = 1.257, 95% CI: 1.174-1.344, P < 0.001), underscoring the multifaceted nature of environmental influences on CO poisoning occurrence.

CONCLUSIONS

Older age and faster hospital admission are associated with more severe CO poisoning outcomes. Meteorological and environmental pollutant factors, including low temperatures, 24-hour temperature fluctuations and elevated CO concentrations, increase the risk of CO poisoning.Public health interventions, such as safety education, improved ventilation, install CO concentration alarm and early warnings during extreme weather, could significantly reduce the incidence of CO poisoning, particularly in colder months with adverse meteorological conditions.