Barriers and determinants of asthma control in children and adolescents in Africa: a systematic review

Relationship between fraction of exhaled nitric oxide and peripheral eosinophilia in asthma

BACKGROUND

Achieving disease control is the goal of asthma management. Serum or sputum eosinophil counts have been known traditional means of assessing eosinophilic airway inflammation in asthma, which is vital in predicting response to corticosteroid therapy which ultimately promotes control of the disease. Evidence suggests that fraction of exhaled nitric oxide (FeNO) may be a more useful non-invasive surrogate biomarker for the assessment of eosinophilic airway inflammation and could help with the timely adjustment of inhaled corticosteroid therapy in the uncontrolled asthma patient. The relationship between FeNO and other markers of airway inflammation has been variable in literature, with limited data in sub-Saharan Africa where FeNO testing is very sparse. We sought to define the relationship between FeNO levels, serum eosinophil counts, spirometry measures and symptom control among asthma patients.

MATERIALS AND METHODS

The study was conducted at the Asthma Clinic of a large tertiary hospital. This study included 82 patients with physician-diagnosed asthma being regularly managed at the clinic. All participants were taken through the asthma control test (ACT), had FeNO and spirometry measurements taken according to the American Thoracic Society (ATS) guidelines. Blood samples were obtained from all participants for serum eosinophil counts. Correlation coefficient was used to ascertain the relationship between FeNO levels and serum eosinophil counts, ACT scores, and spirometry measurements. Logistic regression was used to examine the association between high FeNO and abnormal FEV1 percentage predicted (<80%) with adjustments for age, sex, and BMI.

RESULTS

A total of 82 patients with asthma were included in the study, with higher prevalence of females (72%). Majority (40.2%) of the patients were found in the 60 and above age category. The median FeNO level and ACT score was 42.00 (26.00-52.50) parts per billion (ppb) and 20.0 (18-23) respectively. The median serum eosinophil counts was 0.25(0.90-0.38) × 109/L. The median FeNO levels were significantly higher in patients with partly and very poorly controlled asthma than in the well-controlled group (p < 0.001). A total of 47(57%) of the patients were classified as having well controlled asthma and 35 (42%) uncontrolled. FeNO correlated with serum eosinophil counts (r = 0.450, p < 0.001), ACT (r = -0.648, p < 0.001), and FEV1 percentage predicted (r = -0.353, p = 0.001). High FeNO (>50 ppb) was associated with an over fivefold increased risk of having an abnormal FEV1 percentage predicted.

CONCLUSION

FeNO levels significantly correlated with the ACT scores, serum eosinophil counts and FEV1% predicted among the asthma patients who were on inhaled corticosteroid therapy. High FeNO was significantly associated with abnormal FEV1 percentage predicted. We suggest that the point of care assessment of FeNO is a reliable marker of eosinophilic inflammation in our cohort of patients and together with 'ACT scores' in our asthma clinics could increase asthma control rates.

Analysis of risk factors for depression and anxiety related to the degree of asthma control in children according to gender

OBJECTIVE

The purpose of the study was to investigate whether risk factors involved in the degree of asthma control were the same for children of both genders.

METHODS

This cross-sectional study collected relevant data from 320 children with asthma attending the respiratory asthma clinic at a local children's hospital. All the patients passed the Asthma Control Test (ACT) or the Childhood Asthma Control Test (cACT), lung-function-related tests, the Children's Depression Inventory (CDI), the Screening Scale for Anxiety-Related Mood Disorders (SCARED), and the Family Personal Information Questionnaire.

RESULTS

The study found that gender (p=0.034) was a risk factor for poor asthma control and that girls (odds ratio [OR]=1.669, p=0.042) were more likely to have poor asthma control than boys. Univariate logistic regression analysis found that severe wasting (OR=0.075, p=0.021), depression (OR=43. 550, p<0.001), anxiety (OR=4.769, p=0.036), FEV1% (OR=0.970, p=0.043), FEV1/FVC% (OR=0.921, p=0. 008), and PEF% (OR=0.961, p=0.012) were risk factors for poor asthma control in girls.

CONCLUSION

The risk factors for the degree of asthma control in children with asthma appeared to vary according to gender.

Barriers to childhood asthma care in sub-Saharan Africa: a multicountry qualitative study with children and their caregivers

OBJECTIVES

This study identifies barriers and provides recommendations to improve asthma care in children across sub-Saharan Africa, where qualitative data is lacking despite high rates.

DESIGN

One of the aims of our National Institute for Health Research global health research group 'Achieving Control of Asthma in Children in Africa' was to use qualitative thematic analysis of transcribed audio recordings from focus group discussions (FGDs) to describe barriers to achieving good asthma control.

SETTING

Schools in Blantyre (Malawi), Lagos (Nigeria), Durban (South Africa), Kampala (Uganda) and Harare (Zimbabwe).

PARTICIPANTS

Children (n=136), 12-14 years with either asthma symptoms or a diagnosis and their caregivers participated in 39 FGDs. All were recruited using asthma control questions from the Global Asthma Network survey.

RESULTS

There were four key themes identified: (1) Poor understanding, (2) difficulties experienced with being diagnosed, (3) challenges with caring for children experiencing an acute asthma episode and (4) suboptimal uptake and use of prescribed medicines. An inadequate understanding of environmental triggers, a hesitancy in using metred dose inhalers and a preference for oral and alternate medications were identified as barriers. In addition, limited access to healthcare with delays in diagnosis and an inability to cope with expected lifestyle changes was reported. Based on these findings, we recommend tailored education to promote access to and acceptance of metred dose inhalers, including advocating for access to a single therapeutic, preventative and treatment option. Furthermore, healthcare systems should have simpler diagnostic pathways and easier emergency access for asthma.

CONCLUSIONS

In a continent with rapidly increasing levels of poorly controlled asthma, we identified multiple barriers to achieving good asthma control along the trajectory of care. Exploration of these barriers reveals several generalisable recommendations that should modify asthma care plans and potentially transform asthma care in Africa.

TRIAL REGISTRATION NUMBER

269211.