The risk of asthma exacerbations is higher in asthmatic patients with metabolically unhealthy obesity, according to a study published in the Annals of Allergy, Asthma & Immunology.¹

To identify the prevalence of patients with metabolically unhealthy obesity (MUO) and asthma, the researchers analysed data from the National Health and Nutrition Examination Survey from 2011 to 2016. BMI ≥ 30kg/m² and presence of any one of the following: increased waist circumference, insulin resistance, hyperlipidemia, low physical activity or hypertension was considered as metabolically unhealthy obesity.

A total of 2,685,858 adults with asthma and metabolically healthy obesity and 17,011,880 with asthma and metabolically unhealthy obesity were included in the study. The mean age of the participants was 46.41 years and 44% of them were men. Those with metabolically unhealthy obesity were older (~48 years) compared to those with healthy obesity (41 years).

The likelihood of asthma exacerbation was much higher in patients with increased waist circumference with odds ratio of OR 1.58; this association persisted even after adjustment for age (aOR 1.73). Half of the participants (50.09%) with metabolically unhealthy obesity had asthma, whereas among those with metabolically healthy obesity, just around 8% had asthma. Patients with metabolically unhealthy obesity were 4-times more likely to have needed emergency care for their asthma in the preceding year compared to those with metabolically healthy obesity with OR 3.53 and aOR 3.8. However, no major differences were noted for asthma exacerbations or emergency care when BMI was used to evaluate patients.

This study has thrown some light on the association between asthma and obesity. Rather than BMI alone, the metabolic effects of obesity may influence the course of asthma given that exacerbations and visits to emergency departments were more frequent in asthmatics with metabolically unhealthy obesity. Hence, the presence of metabolically unhealthy obesity may help identify patients who are likely to experience exacerbations of their asthma and avert the need for emergency care.

Reference

1. Greiner B, et al. Prevalence and associations between metabolically unhealthy obesity and asthma exacerbations and emergency department usage. Ann Allergy Asthma Immunol. 2022 Jul 14;S1081-1206(22)00590-7. doi: 10.1016/j.anai.2022.07.005.