Impact of obesity on perinatal outcomes among asthmatic women

Summary of the Dutch Multidisciplinary Practice Guideline on Asthma and Pregnancy

Asthma is the most common chronic respiratory disease in women of childbearing age and during pregnancy. This paper presents a summary of the Dutch multidisciplinary guideline on asthma and pregnancy. The aim of this guideline is to provide structured, where possible, evidence-based recommendations to optimize the management of asthma during pregnancy. The main topics covered in this guideline are preconception counseling, the safety of asthma medications during pregnancy and breastfeeding and risk assessment and monitoring of asthma during pregnancy. Because many caregivers are involved and a uniform approach is desirable, this guideline has been developed in collaboration with all relevant health care providers and patient representatives.

Pregnancy outcomes in the omalizumab pregnancy registry and a disease-matched comparator cohort

BACKGROUND

The Observational Study of the Use and Safety of Xolair (omalizumab) during Pregnancy (EXPECT) pregnancy registry was a prospective observational study established in 2006 to evaluate perinatal outcomes in pregnant women exposed to omalizumab and their infants.

OBJECTIVE

This analysis compares EXPECT outcomes with those from a disease-matched population of pregnant women not treated with omalizumab. Data from a substudy of platelet counts among newborns are also presented.

METHODS

The EXPECT study enrolled 250 women with asthma exposed to omalizumab during pregnancy. The disease-matched external comparator cohort of women with moderate-to-severe asthma (n = 1153), termed the Quebec External Comparator Cohort (QECC), was created by using data from health care databases in Quebec, Canada. Outcome estimates were age adjusted based on the maternal age distribution of the EXPECT study.

RESULTS

Among singleton infants in the EXPECT study, the prevalence of major congenital anomalies was 8.1%, which was similar to the 8.9% seen in the QECC. In the EXPECT study 99.1% of pregnancies resulted in live births, which was similar to 99.3% in the QECC. Premature birth was identified in 15.0% of EXPECT infants and 11.3% in the QECC. Small for gestational age was identified in 9.7% of EXPECT infants and 15.8% in the QECC.

CONCLUSION

There was no evidence of an increased risk of major congenital anomalies among pregnant women exposed to omalizumab compared with a disease-matched unexposed cohort. Given the observational nature of this registry, however, an absence of increased risk with omalizumab cannot be definitively established.

Influence of Maternal Body Mass Index and Macrophage Activation on Asthma Exacerbations in Pregnancy

BACKGROUND

Obesity is a risk factor for exacerbations of asthma, but the mechanisms of this effect in pregnancy are unknown.

OBJECTIVE

This study determined the influence of maternal body mass index, gestational weight gain, eosinophilic inflammation, and systemic macrophage activation on the risk of exacerbations during pregnancy.

METHODS

Women with asthma (n = 164) participated in the study. Body mass index recorded at baseline (17 weeks gestation) was categorized as healthy weight (18.5-24.9 kg/m²), overweight (25-29.9 kg/m²), or obese (>30 kg/m²). Exacerbations requiring medical intervention were recorded prospectively. Asthma control, medication use, and fractional exhaled nitric oxide were assessed monthly; additional visits occurred during exacerbations. Peripheral blood was collected at baseline for the measurement of eosinophils, soluble CD-163, C-reactive protein, and IL-6.

RESULTS

Exacerbations occurred in a higher proportion of overweight (51.1%) and obese (48.4%) women compared with healthy weight women (25%; P = .026). Excess weight gain during pregnancy was not associated with exacerbation risk. Macrophage activation (elevated serum soluble CD-163) was associated with exacerbations requiring oral corticosteroids (P = .043), whereas high peripheral blood eosinophils or fractional exhaled nitric oxide were not associated with exacerbation or oral corticosteroid use.

CONCLUSIONS

Being overweight or obese confers a greater risk of asthma exacerbation during pregnancy, and may be due to systemic macrophage activation.