Characteristics of unintentional carbon monoxide poisoning in Northwest Iran – Tabriz

Spatio-temporal analysis of deaths from carbon monoxide poisoning in Iran between 2011 and 2018: An ecological study

Background and Aims

Mortality caused by carbon monoxide every year threatens the lives of Iranian people, whose spatial and temporal distribution is not known for formulating prevention policies and interventions. This study was conducted to determine the trend of mortality rate changes due to carbon monoxide CO poisoning by Spatio-temporal analysis in Iran from 2011 to 2018.

Methods

An ecological study was conducted based on data from the reports at the National Center for Statistics of Iran for 8 years from 21 March 2011 to 21 March 2018. The number of deaths due to CO poisoning and the annual mortality rates of CO poisoning per 100,000 populations were calculated. To determine the geographical and temporal distribution of death caused by carbon monoxide, spatiotemporal statistical analysis was used.

Results

A total of 6078 deaths were reported due to CO poisoning 4497 deaths were male (74%) and 1596 were female (26%) from 2011 to 2018. Both sexes' mortality rate due to CO poisoning was 1.26 from 2011 to 0.91 in 2018. According to the results, the overall male-to-female ratio was 2.8. The mortality rate due to CO Poisoning had a decreasing trend. However, this trend did not have a linear trend (p = 0.37). The highest mortality due to CO poisoning was seen in the northern and western provinces of Iran.

Conclusion

Our results showed that the mortality rate due to CO poisoning had a decreasing trend during the understudied period. Also, most of the deaths due to CO poisoning occurred in the northern and western provinces of Iran. So, designing prevention programs as well as increasing people's awareness in these regions is recommended.

Global, regional, and national mortality due to unintentional carbon monoxide poisoning, 2000-2021: results from the Global Burden of Disease Study 2021

BACKGROUND

Unintentional carbon monoxide poisoning is a largely preventable cause of death that has received insufficient attention. We aimed to conduct a comprehensive global analysis of the demographic, temporal, and geographical patterns of fatal unintentional carbon monoxide poisoning from 2000 to 2021.

METHODS

As part of the latest Global Burden of Diseases, Injuries, and Risk Factors Study (GBD), unintentional carbon monoxide poisoning mortality was quantified using the GBD cause of death ensemble modelling strategy. Vital registration data and covariates with an epidemiological link to unintentional carbon monoxide poisoning informed the estimates of death counts and mortality rates for all locations, sexes, ages, and years included in the GBD. Years of life lost (YLLs) were estimated by multiplying deaths by remaining standard life expectancy at age of death. Population attributable fractions (PAFs) for unintentional carbon monoxide poisoning deaths due to occupational injuries and high alcohol use were estimated.

FINDINGS

In 2021, the global mortality rate due to unintentional carbon monoxide poisoning was 0·366 per 100 000 (95% uncertainty interval 0·276-0·415), with 28 900 deaths (21 700-32 800) and 1·18 million YLLs (0·886-1·35) across all ages. Nearly 70% of deaths occurred in males (20 100 [15 800-24 000]), and the 50-54-year age group had the largest number of deaths (2210 [1660-2590]). The highest mortality rate was in those aged 85 years or older with 1·96 deaths (1·38-2·32) per 100 000. Eastern Europe had the highest age-standardised mortality rate at 2·12 deaths (1·98-2·30) per 100 000. Globally, there was a 53·5% (46·2-63·7) decrease in the age-standardised mortality rate from 2000 to 2021, although this decline was not uniform across regions. The overall PAFs for occupational injuries and high alcohol use were 13·6% (11·9-16·0) and 3·5% (1·4-6·2), respectively.

INTERPRETATION

Improvements in unintentional carbon monoxide poisoning mortality rates have been inconsistent across regions and over time since 2000. Given that unintentional carbon monoxide poisoning is almost entirely preventable, policy-level interventions that lower the risk of carbon monoxide poisoning events should be prioritised, such as those that increase access to improved heating and cooking devices, reduce carbon monoxide emissions from generators, and mandate use of carbon monoxide alarms.

FUNDING

Bill & Melinda Gates Foundation.

Temporal trends and demographic risk factors for hospital admissions due to carbon monoxide poisoning in England

Unintentional non-fire related (UNFR) carbon monoxide (CO) poisoning is a preventable cause of morbidity and mortality. Epidemiological data on UNFR CO poisoning can help monitor changes in the magnitude of this burden, particularly through comparisons of multiple countries, and to identify vulnerable sub-groups of the population which may be more at risk. Here, we collected data on age- and sex- specific number of hospital admissions with a primary diagnosis of UNFR CO poisoning in England (2002-2016), aggregated to small areas, alongside area-level characteristics (i.e. deprivation, rurality and ethnicity). We analysed temporal trends using piecewise log-linear models and compared them to analogous data obtained for Canada, France, Spain and the US. We estimated age-standardized rates per 100,000 inhabitants by area-level characteristics using the WHO standard population (2000-2025). We then fitted the Besag York Mollie (BYM) model, a Bayesian hierarchical spatial model, to assess the independent effect of each area-level characteristic on the standardized risk of hospitalization. Temporal trends showed significant decreases after 2010. Decreasing trends were also observed across all countries studied, yet France had a 5-fold higher risk. Based on 3399 UNFR CO poisoning hospitalizations, we found an increased risk in areas classified as rural (0.69, 95% CrI: 0.67; 0.80), highly deprived (1.77, 95% CrI: 1.66; 2.10) or with the largest proportion of Asian (1.15, 95% CrI: 1.03; 1.49) or Black population (1.35, 95% CrI: 1.20; 1.80). Our multivariate approach provides strong evidence for the identification of vulnerable populations which can inform prevention policies and targeted interventions.

Carbon monoxide poisoning in Iran during 1999-2016: A systematic review and meta-analysis

BACKGROUND

Carbon monoxide (CO) poisoning is a common cause of emergency department (ED) visits worldwide with high levels of morbidity and mortality. No inclusive nationally statistics of CO poisoning in Iran is available. The present review aimed to describe and review the pattern of CO poisoning in Iran.

METHODS

The search of Medline, SCOPUS, Cochrane library, Google Scholar, Magiran, IranDoc and SID (Scientific Information Database) yielded only 10 studies discussing the epidemiology of CO poisoning in Iran. Outcomes of interest were determining the demographic characteristics, prevalence and mortality rates, annual trends, main sources and mechanisms, location of incidents of CO poisoning as well as providing the safety awareness and precautions.

RESULTS

Totally, 10 studies including 6372 victims of CO poisoning were reviewed. The estimated incidence rate of CO poisoning was 38.91 per 100,000, the proportionate mortality rate was 11.6 per 1000 death and the pooled case fatality rate of was 9.5% (95% CI 6.3%-14.30%). Of the total 5105 individuals with CO poisoning, 2048 (40.12%) were male and 3057 (59.88%) were female. In addition, of 5105 poisoned, 4620 (90.50%) were alive and 485 (9.50%) were dead. The number of fatal CO poisoning cases among men and women were 259 (5.07%) and 226 (4.43%) victims, respectively; while the number of non-fatal CO poisoning cases among men and women were 1790 (35.06%) and 2830 (55.44%) individuals, respectively. The mean age of victims was about 30 years. Most of the victims (36.37%) had the educational level of secondary school, marital status of single (52.74%), and occupational status of housekeeper (27.48%).

CONCLUSION

The incidence, proportionate mortality and case fatality rates of CO poisoning is high in Iran, particularly in young individuals. It seems that preventive strategies should be taught by health care providers more thoroughly and implemented by policy makers more strictly as a mandatory law.

Analysis of hospital admissions due to accidental non-fire-related carbon monoxide poisoning in England, between 2001 and 2010

Background

Accidental non-fire-related (ANFR) carbon monoxide (CO) poisoning is a cause of fatalities and hospital admissions. This is the first study that describes the characteristics of ANFR CO hospital admissions in England.

Methods

Hospital Episode Statistics (HES) inpatient data for England between 2001 and 2010 were used. ANFR CO poisoning admissions were defined as any mention of ICD-10 code T58: toxic effect of CO and X47: accidental poisoning by gases or vapours, excluding ICD-10 codes potentially related to fires (X00-X09, T20-T32 and Y26).

Results

There were 2463 ANFR CO admissions over the 10-year period (annual rate: 0.49/100 000); these comprised just under half (48.7%) of all non-fire-related (accidental and non-accidental) CO admissions. There was seasonal variability, with more admissions in colder winter months. Higher admission rates were observed in the north of England. Just over half (53%) of ANFR admissions were male, and the highest rates of ANFR admissions were in those aged >80 years.

Conclusion

The burden of ANFR CO poisoning is preventable. The results of this study suggest an appreciable burden of CO and highlight differences that may aid targeting of public health interventions.