TOPLINE:

Obesity and metabolic abnormalities were independently associated with an elevated risk for asthma. The combination of both these conditions amplified this risk even further, with a notably stronger effect in women.

METHODOLOGY:

• Researchers performed a cross-sectional analysis using data from the National Health and Nutrition Examination Survey to assess the prevalence of and risk for asthma in US adults across obesity and metabolic phenotypes.
• They included 50,544 participants (median age, 49 years), of whom 6794 had asthma; participants were classified on the basis of their obesity status and the presence of metabolic risk factors.
• Metabolic risk factors included hypertension, hyperglycemia, and dyslipidemia; individuals with obesity and at least two of these factors were classified as having a metabolically unhealthy phenotype.
• Obesity was defined as a BMI ≥ 30, and the presence of asthma was determined from participants’ responses to a health questionnaire.
• Associations between different metabolic phenotypes of obesity and asthma were estimated.

TAKEAWAY:

• The prevalence of asthma was significantly higher in participants with obesity and hypertension than in those without the conditions, whereas it was significantly lower in those with dyslipidemia than in those without hyperlipidemia (P < .05 for all).
• Obesity and hypertension were each linked to a 32% and 19% elevated risk for asthma, respectively (P < .001 for both). Among those with obesity, both metabolically healthy and unhealthy individuals had elevated risks, with the metabolically unhealthy subgroup showing the strongest effect (odds ratio, 1.39; P < .001).
• The risk for asthma increased progressively with the number of combined metabolic risk factors, with obesity combined with three metabolic risk factors increasing the risk for asthma by 32% (P = .005).
• Participants with both obesity and hypertension had a 49% (P = .001) higher risk for asthma than those without obesity and metabolic abnormalities, with the effect particularly pronounced in women.

IN PRACTICE:

“Through early identification and intervention in these high-risk groups, the precision and effectiveness of asthma prevention and control can be improved, such as targeting MUO [metabolically unhealthy obese] females with hypertension in clinical guidelines, which in turn will reduce the burden of asthma-related diseases and improve the quality of life of patients,” the authors of the study wrote.

SOURCE:

The study was led by Ruiqi Zhao, Heilongjiang University of Chinese Medicine, Harbin, China. It was published online on August 28, 2025, in BMC Pulmonary Medicine.

LIMITATIONS:

The cross-sectional study design precluded establishing clear causal relationships. Asthma diagnoses were based on questionnaires and self-reports, introducing potential recall bias and misdiagnosis. Moreover, the study did not adequately explore relationships across racial subgroups.

DISCLOSURES:

The study was supported by the National Natural Science Foundation of China. The authors reported having no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.