Among patients aged 12 to 21 years with asthma, outpatient exacerbation rates decreased from 13.4% to 7.8% after metaformin was prescribed
Metformin use may be associated with improved exacerbation rates in adolescents and young adults with asthma, according to study findings published in Pediatric Pulmonology.
Metaformin, a common diabetes medication that may have anti‐inflammatory and antioxidative effects, has been linked to a lower risk for asthma exacerbations in adults. Researchers sought to assess how metaformin use affected exacerbations in adolescents and young adults with asthma, using from the Arkansas All‐Payer Claims Database from 2013 to 2018 and the Arkansas School BMI database.
Study participants were 12 to 21 years of age with an asthma diagnosis. Study outcomes were asthma exacerbations in the outpatient, inpatient, and emergency room (ER) settings. Metformin use was determined by prescription refill rates.
A total of 464 patients (median age, 16 years; 25% male; 37% Hispanic) were included. Of the cohort, 29.3% had exacerbations; 14.2% had exacerbations before their first metformin prescription, 10.3% afterward, and 4.7% before and after. Analyses were conducted in the full sample of 464 patients and in the 136 patients who had at least 1 exacerbation in the pre‐index and/or postindex periods (ie, the reduced sample).
Regarding outpatient exacerbation events, 13.4% of participants had exacerbations only in the pre-index period and 7.8% only in the postindex period (McNemar’s P =.009). The rank correlation showed that postindex decreases were more pronounced in patients with higher adherence in the full sample (r = −.165, P < 001) and reduced sample (r = −.228, P =.009). These rank correlations with adherence were no longer significant after adjustment for potential confounders (r = −.029; P =.550 for the whole sample and r = −.146; P =.102 for the reduced sample).
For ER exacerbations, 4.3% of patients had an exacerbation only in the pre-index period and 5.6% only in the postindex period (McNemar’s P =.376). For the rank correlations, postindex decreases were more pronounced with greater adherence in the whole sample (r = −.103, P =.029) and reduced sample (r = −.172, P =.051). After adjustment, these associations with adherence were not significant (r =.079; P =.106 in the whole sample and r =.052; P =.564 in the reduced sample).
Inpatient exacerbation events occurred in 4 patients (1 in the pre‐ and postindex periods and 3 in the postindex period), and the standard nonparametric tests showed no statistical evidence that metformin changed annualized rates.
Among all exacerbation events, rank correlations of adherence with overall rate changes demonstrated improved rates with increased adherence (r = −.174; P <.001 in the full sample and r = −.196; P =.023 in the reduced sample). These correlations were attenuated after adjustment to 0 (r = −.021 for the whole sample and r = −.097 for the reduced sample; both P >.274).
Among several limitations, there was no information regarding whether metformin changed exacerbation rates for 70% of participants. Additionally, the researchers did not evaluate how exacerbations were affected by other relevant confounders such as socioeconomic status, smoking exposure, and allergens; actual medication adherence was unknown; and data on the severity of asthma and chronic symptoms were not available.
“[M]etformin use is associated with improved asthma exacerbations among adolescents and young adults with asthma,” the researchers concluded. They further stated that their study was the first to examine the effect of metaformin on asthma exacerbations in a large pediatric population, and that controlled trials with larger sample sizes were needed.
Ararat E, Landes RD, Forno E, Tas E, Perry TT. Metformin use is associated with decreased asthma exacerbations in adolescents and young adults. Pediatr Pulmonol. Published online September 29, 2023. doi:10.1002/ppul.26704