PREVALENCE, SYMPTOMS AND MANAGEMENT OF CHILDHOOD ASTHMA: A COMPARISM OF URBAN AND RURAL AREAS IN NIGERIA
A community based survey was carried out in January, 2010 amongst school children aged 8 to 12 years, on the ‘Prevalence, Symptoms and Management of Childhood Asthma’ and these were compared between urban and rural subjects in Nigeria.
Two schools each were selected from both rural and urban areas of Enugu State, Nigeria by balloting the list of approved primary schools and the subjects by multistage cluster sampling method. A pretested, modified ISAAC questionnaire was used to elicit responses from caregivers (parent/guardian) of these selected pupils. The responses obtained was analysed using SPSS version 11 and statistical significance determined with Chi – square at a level of significance of 0.05.
A total of 485 (four hundred and eighty five) pupils from 4 (four) schools aged 8 to 12 years were studied; 241 (two hundred and forty one) from urban and 244 (two hundred and forty four) from rural schools.
The study revealed an atopy prevalence of 25.7% in urban and 23.4% in rural areas with no difference between the urban and rural prevalence.
Asthma was shown to have a prevalence of 12.3% in the urban area and 11.8% in the rural area, again with no difference between both geo-locations (P = 0.961).
Of all the symptoms of asthma compared, only the frequency of day time wheeze was found to be significantly higher in the urban area than in the rural area (P = 0.049) .
The ability to diagnose asthma correctly was significantly low in both geo-locations with urban diagnosis level of 35.7% and rural level of 10.7%.
Standard asthma management was found to be unacceptably poor in both geo-locations, except for patients’ counseling on health situation which was quite high – 60.7% in urban area compared to 11.1% in the rural area. Markers of standard asthma management were significantly more in use in the urban area compared to the rural area, except for regular follow- up visits that was similar in both geo- locations with a P-value of 0.682.
The morbidity pattern shows significantly higher school absenteeism (P = 0.012), acute severe exacerbation of symptoms (P = 0.007) and hospital admissions in the urban area compared to the rural area.
The findings in this study showed that there is an increasing trend in the prevalence of childhood asthma in both urban and rural areas of Nigeria. The symptom severity, level of diagnosis, and use of standard asthma management protocol, even though unacceptably low in both geo- locations was significantly higher in urban area compared to rural area.
Training and re-training of health workers on early diagnosis and standard management protocol as well as commencing regular follow up clinics for childhood asthma patients were recommended.
TABLE OF CONTENTS
Title Page i
Table of Contents viii
List of Tables List of Figures xi xii
1.0 Introduction 1
1.1 Background of the Study 2
1.2 Statement of Problem 3
1.3 Rationale for the study 6
1.4 Aims and Objectives 8
1.4.1 General Objective 8
1.4.2 Specific Objectives 8
CHAPTER TWO: LITERATURE REVIEW
2.1 Epidemiology 10
2.2 Pathophysiology 11
Trigger Factors 13
Clinical Features 13
Monitoring Severity 21
Avoiding Risk factors 22
Long–Term Medication 23
Treating Asthma Attacks 24
Regular Follow-Up Care 25
Morbidity and Mortality Pattern/Complications 25
CHAPTER THREE: MATERIALS AND METHOD
3.1 Study Area 27
3.2 Inclusion Criteria 29
3.3 Exclusion Criteria 29
3.4 Study Design 30
3.5 Study Population 30
3.6 Sample Size and Sampling Method 30
3.7 Sampling 31
3.8 Ethical Considerations 32
3.9 Consent 33
Survey Instrument and Data Collection 33
Data Analysis 34
Demographic and Other Characteristics of the Study Population 36
Atopic Prevalence 40
Asthma Prevalence 41
Asthma Symptoms and diagnosis 43
Asthma Morbidity 46
Asthma Management 48
Asthma Symptoms and Diagnosis 55
Asthma Morbidity 58
Asthma Management 58
Limitations of the Study 64
Appendix A 74
Appendix B 75
Appendix C 78
Appendix D 80
LIST OF TABLES
Table I: Demographic Characteristics of Respondents 36
Table II: Distribution of Anthropometric Parameters of Respondents 37
Table III: Distribution of Current Asthma among Different Ages Studied 41
Table IV: Distribution of Current Asthma Prevalence for Sex and Geo-location 42`
Table V: Distribution of the Severity of Current Asthma Symptoms 43
Table VI: Distribution of Asthma Morbidity Pattern 46
Table VII: Distribution of the Use of Standard Asthma Management 48
LIST OF FIGURES
Figure 1. Distribution of Caregiver’s Educational Level 38
Figure 2. Social Class Distribution of Respondents 39
Figure 3. Distribution of Atopic Symptoms 40
Figure 4. Proportion of Asthma Diagnosed by a Doctor or a Nurse 45
BACKGROUND OF THE STUDY
Asthma is a very common chronic illness affecting children, and it is a major global health problem in developed countries.1 A consistent trend for higher prevalence of wheezing and asthma in more affluent westernized societies has been shown repeatedly.2 Among children, higher prevalence rates have been found in industrialized Western countries than in developing countries of Asia and Africa. 3
Despite modern treatment approaches recommending usage of potent anti-inflammatory (corticosteroid) drugs, asthma prevalence, morbidity and mortality in childhood are all increasing worldwide.1, 4, 5, 6 Several studies from different parts of the world that used serial questionnaire surveys are reporting an increased prevalence of asthma, and also that there is wide variability in prevalence between populations.7 It appears that differences in asthma prevalence between population groups are due to differential exposure to environmental factors; genetic variation alone could not account for the rise in the prevalence of disease over a few decades.5 Allergen exposure in early life appears to correlate with sensitization and expression of asthma and atopy.5 Lifestyle factors, including diet and ambient air quality may be disease modifiers.8 These differences may be real or they may reflect study methodology.9 The etiology of these conditions remains poorly understood, despite a large volume of clinical and epidemiological research within populations that has been directed at explaining why some individuals and not others develop asthma and allergies.2 Numerous surveys have been conducted in various
countries, and there is a large body of literature on the subject. 7 At the moment, there is considerable interest in the international comparison of asthma prevalence, stimulated by the growing evidence of an increment in the frequency.10 Numerous studies have assessed the epidemiology of asthma on the basis of morbidity and mortality data or from questionnaires.9 Among the different studies designed for this objective, the ISAAC (International Study of Asthma and Allergies in Childhood) project has had universal acceptance.
ISAAC was created in 1991 to facilitate research into asthma, allergic rhinitis and eczema by promoting a standardized methodology.11 ISAAC developed from a merger of two multinational collaborative projects, each of them examining variations in childhood asthma. These were an initiative from Auckland, New Zealand to conduct an international comparative study of asthma severity and an initiative from Bochum, Germany for an international study to monitor time trends and determinants of the prevalence of asthma and allergies in children. The ISAAC project is made up of three phases: Phase I, Phase II and Phase III. 11 ISAAC was the first study carried out worldwide using standardized questionnaires in order to create a reliable global map of childhood allergy.
STATEMENT OF PROBLEM
It is now estimated that as many as 300 million people of all ages, and all ethnic backgrounds, suffer from asthma and the burden of this disease to governments, health care systems, families, and patients is increasing worldwide. In 1989, the Global Initiative for Asthma (GINA) program was initiated with the U.S. National Heart, Lung, and Blood Institute, National Institute for Health (NIH) and the World Health Organization (WHO) in an effort to raise awareness among public health and government officials, health care workers, and the general public that asthma was on the increase.
The GINA program recommends a management program based on the best available scientific evidence to allow doctors to provide effective medical care for asthma tailored to local health care systems and resources. Working in continued collaboration with leaders in asthma care from many countries, and with GINA sponsors, World Asthma Day (first Tuesday in May) has been extremely successful, increasing in numbers of participants each year.11
The rate of asthma increases as communities adopt western lifestyles and become urbanized. This is because most western processed food items are antigenic and with urbanization and industrialization, a lot of environmental pollutants are emitted to the atmosphere that are antigenic and irritants to the airways. With the projected increase in the proportion of the world's population that is urban from 45% to 59% in 2025, there is likely to be a marked increase in the number of asthmatics worldwide over the next two decades. It is estimated that there may be an additional 100 million persons with asthma by 2025. Asthma is estimated currently to account for about 1 in every 250 deaths worldwide. 11 The number of disability-adjusted life years (DALYs) lost due to asthma
worldwide has been estimated to be currently about 15 million per year, and ranked 25th leading cause of DALYs lost worldwide. It also accounts for around 1% of all DALYs lost, which reflects the high prevalence and severity of asthma. The number of DALYs lost due to asthma is similar to that for diabetes, cirrhosis of the liver, or schizophrenia.11 The economic cost of asthma is considerable both in terms of direct medical costs (such as hospital admissions and cost of pharmaceuticals) and indirect medical costs (such as time lost from work and premature death).11
New Zealand has one of the highest prevalence rates of asthma in the world, with asthma occurring in about 15% to 20% of children and adults and affecting at least 600,000 people.12
Similarly, the burden of asthma in the United States of America (USA) has increased in the last two decades. The trend from 2003 to 2005 clearly showed this increase. In 2005, there were three (3) different asthma prevalence estimates: Lifetime asthma diagnosis, Current asthma and Asthma attack prevalence. 13 Current asthma was then estimated at 7.7% of the population of 22.2million people. This decreased with age; 8.9% of children (6.5million) compared to 7.2% of adults (15.7million). Asthma attack was estimated at 4.2% of the people (12.2million) had at least one attack in the previous year. This also decreased with age; 5.2% of children (3.8million) compared to 3.9% of adults (8.4million). Lifetime asthma diagnosis of 11.2% of people (32.6million) had ever been diagnosed with asthma during their lifetime. On the contrary, this increased with age; 10.7% of adults (23million) compared to 12.7% of children (9million).
GINA study ranks Nigeria as number 49 in its ranking of 84 countries with prevalence of current asthma symptoms in childhood. That is, cases of self-reported wheezing in the
previous 12 months period in 13 to 14 year-old children. The study also reveals that 5.4 per cent (about 6 million) of Nigerians suffer from asthma. The study however failed to provide more information on the situation in Nigeria due to lack of standardized data.11 Oduwole noted that half of all cases of asthma develop before the age of 10years and about 80% of this develops before the age of 5years. It is the third major cause of hospitalization in children younger than 5years because their airways are very narrow and they have smaller lungs.14 A study on under 5 mortality pattern in Lagos state, Nigeria shows that acute asthma contribute 0.6% to total death.15 This compares with the mortality rate of childhood asthma in Benin city, Nigeria of 0.83%.16 Mortality in Nigeria generally noted to be less than 1%.Asthma mortality was seen more in girls especially during or near puberty. In these cases, death occurs suddenly, often following extreme excitement or agitation. Many of the deaths are preventable, being due to suboptimal long-term medical care and delay in obtaining help during the fatal attack.16 Nigeria was classified by WHO as one of the countries with less than 50% access to essential drugs, including asthma medications.11
Some factors postulated to contribute to the rise of asthma prevalence worldwide, including Nigeria are as follows: Eating junk foods joints containing less fiber, mineral salts and other nutrients that protect against asthma; sedentary lifestyle in children especially in urban areas which include spending time watching television, video, playing computer games and thus over exposure to indoor allergens; higher survival of low birth weight infants (Premature infants), who have been proven to be more susceptible to asthma; reduced breastfeeding despite campaign for exclusive breastfeeding, as omega- fatty acids in breast milk protect against asthma. 14 Although about one third of all cases
of asthma are hereditary, there is also a relationship between early childhood respiratory and intestinal infections (especially of viral origin) and development of asthma in later age.14
RATIONALE FOR THE STUDY
Despite the large body of literature on asthma especially on clinical and epidemiological surveys within populations, the prevalence, morbidity and mortality has continued to increase worldwide. The advent of ISAAC and GINA started worldwide comparison studies with standardized instruments. These bodies have also been involved in advocacy and health education. They have brought to limelight the burden of asthma worldwide as to become of public health interest.
Studies have shown great variability in the prevalence of asthma across regions of the same country and across countries of the world due to differential exposure to environmental factors, genetics, lifestyle and ambient air quality.10, 11 It is likely that above variations may also exist between different settlements of the same region of a country i.e. rural and urban area especially from lifestyle and environment. Studies have also shown that severity of asthma symptoms, the way it is perceived, diagnosed and managed vary from country to country.17 A lot more is known about asthma, and its management has been dynamic, undergoing constant review by GINA working group.18 How much of this new trend is known and practiced in Nigeria?
Although interest has awakened for asthma studies in Nigeria, most studies have been done in the western and northern axis of the country. Little studies have been conducted in the eastern part of the country. There are no studies in Nigeria currently to the best of
my knowledge that looked at local prevalence, demographics, symptoms, diagnosis and management of asthma in Enugu or any other eastern sub region. This study compared above mentioned parameters within the urban and rural sub-regions of the eastern part of Nigeria. The result is compared with standard practices, similar studies done elsewhere in the world and trends determined. Capacity building need areas were identified and better awareness will be created through training and retraining of health workers, mass mobilization and health education, as well as well-coordinated intervention government policies. All these will aim at helping to achieve the Millennium Development Goal (MDG) 4 of significantly reducing child mortality by 2015.
AIMS AND OBJECTIVES
To compare the prevalence, symptoms and management of childhood asthma in rural and urban areas of Enugu State.
1. To determine the prevalence of childhood asthma in urban and rural areas of Enugu.
2. To elicit the symptoms of childhood asthma in urban and rural areas of Enugu.
3. To determine the management modalities of childhood asthma in urban and rural areas of Enugu.
4. To compare 1-3 in urban and rural areas of Enugu.
1. H0 – There is no significant difference in the prevalence of childhood asthma between the urban and rural areas of Enugu.
H1 - There is a significant difference in the prevalence of childhood asthma between the urban and rural areas of Enugu.
2. H0 – There is no significant difference in the symptoms of childhood asthma between the urban and rural areas of Enugu.
H1 -- There is a significant difference in the symptoms of childhood asthma between the urban and rural areas of Enugu.
3. H0 --- There is no significant difference in the management of childhood asthma between the urban and rural areas of Enugu.
H1---There is a significant difference in the management of childhood asthma between the urban and rural areas of Enugu..