CHAPTER 4: THE RESPIRATORY HEALTH CONDITIONS IN CHILDREN
4.3 Materials and methods
This cross sectional study was conducted in Clare Estate located in Durban at eThekwini Municipality, South Africa. The population of Clare Estate is diverse, comprising a combination of formal and informal dwellers who are mainly Africans and Indians. This settlement is located close to the Bisasar Road landfill site which is approximately 6 km away from the city of Durban.
Although spirometry is recommended as a basis for diagnosing impaired lung function (Global Initiative for Chronic Obstructive Lung Disease 2006), it is not always possible to use it exclusively in field research as it is costly and fragile to transport. Therefore, the respiratory symptom-based questionnaires can be an alternative and cost effective tool to enable the identification and diagnosis of patients with respiratory illnesses (Abbasi et al. 2012). In developing countries, including South Africa, issues of accessibility and scarcity of resources require the use of alternative methods particularly in distant rural areas (Abbasi et al. 2012).
Price et al. (2006) urges that symptoms based on questionnaires can be a useful adjunct in the screening of population for respiratory illnesses when used in conjunction with spirometry.
A number of respiratory questionnaires with questions on symptoms of chronic obstructive pulmonary disease (COPD) and asthma were developed (Leite et al. 2008, Shin et al. 2010).
The American Thoracic Society Division of Lung Disease questionnaire (ATS-DLD-78A) is a generally used questionnaire for identifying the respiratory symptoms (Ferris 1978). It contains
questions relating to frequent and chronic respiratory symptoms including cough, phlegm, wheeze and shortness of breath (Abbasi et al. 2012).
Respiratory health conditions of children were collected without assessing the source of pollution attributed to the presented respiratory conditions. Ideally, the individual sources of pollution must be assessed to eliminate the effects of other variables that could possibly have an impact on the reported respiratory health conditions. During data collection, parents or caregivers were asked questions pertaining the children’s respiratory health conditions and allergies. Those conditions include the occurrences of wheeze, breathlessness and the doctor’s diagnosis. A parent/caregiver report of doctor-diagnosis included the following respiratory conditions: asthma, asthmatic bronchitis, allergies, eczema, chronic bronchitis, and reactive airway disease. The occurrence of wheeze was categorised into three segments, namely: ever wheezed, current wheeze, and current severe wheeze.
4.3.1 Sample selection
A total of 181 children aged between 6 and 12 years participated in the child health screening questionnaire. Children were recruited from 157 households in Clare Estate, Durban from house to house visits to homes within 2 km radius of the Bisasar Road landfill site. Study participants were recruited from their homes by research assistants guided by the following inclusion criteria:
children residing in households situated within a 2-km radius of the landfill sites were enlisted to participate;
children aged between 6 and 12 years at the beginning of 2012 were engaged to participate;
children who have resided within the defined area (2 km) for a period of 5 years or longer were enlisted to participate;
parents or child caregivers who were 18 years old and above were allowed to be respondents; and
parents or caregivers who had resided with the said child for a period of at least 5 years were allowed to participate.
4.3.2 Data collection
A standardised respiratory health screen questionnaire was utilised to collect children’s respiratory health data from parents or caregivers. Data was collected for a period of four months (September to December 2012). The study used a modified version of the American Thoracic Society Division of Lung Disease questionnaire (ATS-DLD-78A) to record the occurrence of respiratory symptoms. It comprised questions regarding frequent cough (defined as presence of cough on most days for three consecutive months or more during the year), chronic cough (defined as presence of cough for three consecutive months in a year), frequent phlegm (defined as bringing up phlegm on most days of the month, for three consecutive months or more in a year), chronic phlegm (presence of phlegm for three consecutive months in a year), frequent wheezing (whistling sound heard on expiration), chronic wheezing (whistling sounds heard on expiration for a year), shortness of breath Grade I (shortness of breath when hurrying on ground level or walking up a slight hill) and Grade II (dyspnoea defined as: walking slower than people of the same age on level ground because of breathlessness or having to stop to breath when walking at own pace on level ground), self- reported asthma (defined as respondent having had asthma) and physician-diagnosed asthma (defined as asthma confirmed by a doctor), chronic bronchitis (defined as chronic bronchitis confirmed by a doctor) ( eThekwini Municipality. 2007, Abbasi et al. 2012, Reddy et al. 2012).
The Child Health Screening Questionnaire was administered by trained fieldworkers to qualifying parents and caregivers in households where there were children that met the inclusion criteria. The Child Health Screening Questionnaire incorporated questions regarding a child’s demographic information and respiratory health symptoms, and a doctor’s diagnosis of the respiratory health diseases.
This study used parent/caregiver report of doctor-diagnosis, and chronic symptom and condition recall to define the health outcome. For this study, chronic symptoms and conditions refer to “wheezing, breathlessness, asthma, reactive airway disease, asthmatic bronchitis, and eczema”. In this study, the following health outcomes were computed, on the basis of positive answers from the written questionnaire: ever wheeze [“Does (child) ever sound wheezy or whistling], and [Has [child] ever had an attack of wheezing that has made him/her feel short of breath? For both questions, options were “yes” or “no”.
Breathlessness of individual was defined as those who, according to the written questionnaire, responded positively (with a ‘yes’) to all three questions:
1. Is [child] troubled by shortness of breath when hurrying on level ground?
2. Does [child] get short of breath walking with other children of his/her own age on level ground?
3. Does [child] have to stop for breath when walking at his/her own pace on level ground?
Current severe wheeze was defined as those who, according to the written questionnaire, responded positively to all four questions:
1) “In the past 12 months, how often has your child had wheezing (a whistling sound from the chest) with a cold?” For this question, the parent or caregiver could select one of the following four options: a) more than once per month, b) three to 12 times in the whole year, c) once or twice in the whole year or d) never. Included in the definition of severe wheeze were those who wheezed more than once per month. 2) “In the past 12 months, how often has your child had wheezing (a whistling sound from the chest) without a cold?” 3) “In the past 12 months, how often has your child wheezed while exercising, running or playing?”4) “In the past 12 months, how often has your child had an attack of wheezing that made it hard to breathe or catch his or her breath?”. For this question, the parent or caregiver could select one of the following three options: a) every day, b) more than two times per week, c) more than once per month d) three to 12 times in the whole year, e) once or two times in the whole year, and f) never. Included in the definition of severe wheeze for questions 2-4 were those who indicated every day or more than twice per week or more than one time per month.
3.3.3 Data analysis
The collected data about children’s respiratory health was then captured into Microsoft Excel software by research assistants. Double data entry was performed by the researcher before the data was analysed. Descriptive statistics and frequency distribution were used to analyse and interpret data.
4.3.4 Ethical considerations
Study approval was sourced from the Ethics Review Committee of the Biomedical Research Ethics Committee of the University of KwaZulu-Natal (Ethical clearance number: BE201/11).
Verbal and written informed consent was sourced from the participants.