Study Finds 8.7% of the US Population Has Asthma

Asthma affected 8.7% of the US adult population between 1999 and 2020, with female gender, low income, obesity, and smoking status being the most significant risk factors.

Wooden blocks spell ASTHMA | gustavofrazao - stock.adobe.com

These findings highlight the importance of public health policies to these address risk factors and help reduce the burden of this condition, especially among those who have the highest likelihood of being affected. The population-based study is published in Scientific Reports.

“Asthma is a prevalent respiratory condition that poses a substantial burden on public health in the United States,” wrote the researchers of the study. “Understanding its prevalence and associated risk factors is vital for informed policymaking and public health interventions. This study aims to examine asthma prevalence and identify major risk factors in the US population.”

The study utilized data from the National Health and Nutrition Examination Survey (NHANES), a comprehensive survey conducted by the National Center for Health Statistics (NCHS) to understand the relationship between nutritional status, health promotions, and disease prevention.

Initially, 116,876 individuals were included in the participant pool who participated in NHANES surveys. After excluding individuals under age 20 years and participants with missing data, a total of 64,222 individuals were available for analysis.

The researchers performed a binary regression analysis to observe the relationship between demographics and health-related covariates with the prevalence of asthma.

Asthma was found to have affected 8.7% of the US population. Gender was found to be a significant risk factor, with 36% of individuals with asthma being male and 64% female, making females 1.76-times more likely to have asthma than males (P < .001).

Participants aged 60 years and older (34%) had the highest asthma prevalence, while participants aged 20-29 years (18.4%) had the lowest asthma prevalence.

Obese individuals had a 1.74-times greater likelihood of having current asthma compared with underweight individuals (P < .001). Smoking was also associated with asthma, with smokers (51.2%) having a higher rate of asthma compared with non-smokers (48.4%). Additionally, 38.5% of individuals in low-income households had asthma, compared with 26.1% of individuals in high-income households.

Furthermore, non-Hispanic White (46.4%) individuals had the highest asthma prevalence, followed by non-Hispanic Black (26%) participants. In comparison, Mexican Americans (9.6%) and other Hispanic (9%) individuals were found to have the lowest asthma rates, respectively.

However, the researchers acknowledged some limitations to the study. Because the study was based on NHANES data, it may have led to underrepresentation of specific subgroups within the US. Additionally, the study utilized self-reported data, including self-reported physician diagnoses of asthma. This may have resulted in recall bias and misclassification of asthma cases.

Despite these limitations, the researchers believe the study determined that 8.7% of the US population has asthma, with female gender, low income, obesity, and smoking found to be significant risk factors for asthma prevalence.

“Health policy and decision makers, clinicians, and researchers can use the asthma statistics from the NHANES dataset that is presented here to help design programs and action plans that address risk factors like being female, having low income, being obese, and smoking,” wrote the researchers. “These plans can also be used to improve the quality of care for asthma patients and lessen the burden that the condition puts on them by providing appropriate, easily accessible, and effective treatment.”

Reference

Swed S, Sawaf B, Al-Obeidat F, et al. Asthma prevalence among United States population insights from NHANES data analysis. Sci Rep. 2024;14(1):8059. Published 2024 Apr 5. doi:10.1038/s41598-024-58429-5