Treatable Traits in Pregnant Women With Asthma: a Retrospective Study of Prevalence and Associations With Exacerbation and Poor Asthma Control

BACKGROUND: Treatable traits personalize asthma management, yet their prevalence and associations with exacerbations and asthma control in pregnancy are understudied. OBJECTIVE: To determine the prevalence of 18 treatable traits and their associations with exacerbations and asthma control in pregnant women with asthma. METHODS: We examined Breathing for Life Trial clinical records to identify 18 potential treatable traits from mid-pregnancy. Regression models adjusted for confounders determined associations with future exacerbations during pregnancy. In a subgroup, traits associated with asthma control were assessed at multiple time points during pregnancy using a generalized linear mixed model. RESULTS: Pregnant women (n = 761) with mild to moderate asthma exhibited a median of 36% of possible traits assessed. Prevalent treatable traits included no asthma action plan (84.2%), inhaler device polypharmacy (82.1%), and iron deficiency (70.4%). A history of exacerbation (adjusted odds ratio [OR] = aOR 2.47; 95% CI, 1.61-3.78; P < .002) and significant nausea (OR = 1.88; 95% CI, 1.24-2.85; P = .039) were associated with increased exacerbation whereas a history of exacerbation was associated with increasing exacerbations (adjusted incidence rate ratio = 2.26; 95% CI, 1.51-3.40; P = .002) after adjusting for confounders and multiple comparisons. In mid-pregnancy, inhaler device polypharmacy (OR = 2.72; 95% CI, 2.08-3.57; P = .002), current smoking (OR = 2.51; 95% CI, 1.36-4.63; P = .039), and a history of exacerbations (OR = 1.95; 95% CI, 1.26-3.02; P = .039) were associated with poorer asthma control. CONCLUSIONS: Behavioral and risk factor traits are common in asthma during pregnancy. A history of exacerbation and significant nausea were associated with increased exacerbation risk. Inhaler device polypharmacy, smoking, and a history of exacerbations were associated with poor asthma control in mid-pregnancy.