The relationship between asthma control and health-related quality of life in asthma and the role of atopy: a cross-sectional study of Nigerian adult asthmatics.

INTRODUCTION: the relationship between asthma control and health-related quality of life (HRQoL) in adult asthmatics is fairly established, but the unique contribution of atopy to this relationship has received less attention. The aim of this study was to quantify the contribution of atopy to this relationship. METHODS: in a cross-sectional study, we assessed HRQoL using mini-Asthma Quality of Life Questionnaire (AQLQ). Asthma control, atopy and lung function were assessed using the Asthma Control Test (ACT), skin prick test and spirometry respectively. Hierarchical multiple regression was used to examine the association between of HRQol and asthma control, atopy and other clinical and demographical factors. RESULTS: eighty-two adult asthmatics (59 females), with median age of 44 years and median duration of asthma of 15 years were recruited from a tertiary hospital. Fifty-two (63%) were classified as atopic based on sensitization to at least one aeroallergen. The atopic individuals were younger and had better quality of life in activity domain; however, there was no significant difference between the atopic and non-atopic asthmatics in ACT score (19.0 vs 18.0) p=0.91, total AQLQ score (4.9 vs 4.6) p=0.22. The ACT scores correlated positively with total AQLQ scores [rho= 0.53, 95% Confidence Interval (CI) 0.35, 0.67; p< 0.001]. However, atopy contributed significantly to the emotional domain of HRQoL score, p=0.028. CONCLUSION: we concluded that better asthma control is associated with better quality of life and atopy contributed uniquely to emotional domain in health-related quality of life.

Chronic airflow obstruction and ambient particulate air pollution.

Smoking is the most well-established cause of chronic airflow obstruction (CAO) but particulate air pollution and poverty have also been implicated. We regressed sex-specific prevalence of CAO from 41 Burden of Obstructive Lung Disease study sites against smoking prevalence from the same study, the gross national income per capita and the local annual mean level of ambient particulate matter (PM2.5) using negative binomial regression. The prevalence of CAO was not independently associated with PM2.5 but was strongly associated with smoking and was also associated with poverty. Strengthening tobacco control and improved understanding of the link between CAO and poverty should be prioritised.

Challenges of diagnosing and managing bronchiectasis in resource-limited settings: a case study.

Bronchiectasis, once an orphan disease is now gaining renewed attention as a significant cause of morbidity and mortality. It is a morphologic term used to describe abnormal, irreversibly dilated and thick-walled bronchi, with many etiologies. The management of bronchiectasis can be challenging because its pathogenetic mechanisms is still evolving. Its diagnosis and management is particularly more demanding especially in resource-limited settings like Nigeria because of delayed diagnosis and improper management with devastating consequences, hence this case study.

Domestic solid fuel combustion in an adult population in Nigeria: A cross sectional analysis of association with respiratory symptoms, quality of life and lung function.

BACKGROUND AND OBJECTIVES: We examined the association of respiratory symptoms, health status, and lung function with the use of solid fuel (wood, charcoal, coal or crop residue) for cooking or heating in a predominantly non-smoking population. METHODS: Using the protocol of the Burden of Obstructive Lung Diseases (BOLD) initiative, we collected representative population data using questionnaires and spirometry tests. We categorized solid fuel use into 'never user', 'ex user' and 'current user' based on responses to the survey. We developed regression models to evaluate the relation between use of solid fuel and the prevalence of respiratory symptoms, quality of life and lung function adjusting for confounding variables. RESULTS: Out of 1147 respondents with complete information on domestic fuel type, 33% were 'never-users', 19% were 'ex-users' while 48% reported current use of solid fuel for domestic cooking and/or indoor heating. Compared with never-users, current solid fuel users were more likely to report cough (OR: 1.7, 95% CI: 1.0, 2.9), cough or phlegm (OR: 1.6, 95% CI: 1.0, 2.5) and the association was stronger among women (OR: 3.0, 95% CI: 1.3, 7.1 and OR: 2.3, 95% CI: 1.1, 5.2, respectively). Current solid fuel users also had lower mental health status (coefficient: ?1.5, 95% CI: ?2.8, - 0.2) compared with the group of never-users. Current or previous domestic use of solid fuels for cooking or heating was not associated with higher prevalence of chronic airflow obstruction (FEV1/FVC < LLN). CONCLUSIONS: Using solid fuel for domestic cooking or heating was associated with a higher risk of cough or phlegm and a lower mental quality of life. However we found no significant effect in the prevalence of chronic airflow obstruction in Ife, Nigeria.

Biomass smoke exposure as an occupational risk: cross-sectional study of respiratory health of women working as street cooks in Nigeria.

OBJECTIVE: Little is known about respiratory health of women who are occupationally exposed to biomass smoke outside their homes. This study reports the exposure and respiratory health of street cooks in Ile-Ife, Nigeria. METHODS: We assessed exposure to biomass smoke by questionnaire in 188 street cooks and 197 control women and by personal diffusive samplers to quantify volatile organic compounds (VOCs) in a subsample of the women. Respiratory symptoms were assessed by a standardised questionnaire, and pulmonary function was assessed by spirometry before and after bronchodilation. Regression analysis was conducted to compare the outcome between the two groups. RESULTS: The study included 188 women (median age 40, IQR 30-50 years) who had worked as street cooks for a median of 7 years (IQR 3-15 years) and 197 control women with similar demographics. Benzene concentration in passive samplers worn by the street cooks was significantly higher compared with controls (median (IQR) 119.3 (82.7-343.7) µg/m3 vs 0.0 (0.0-51.2) µg/m3, p<0.001). The odds of reported respiratory symptoms were significantly higher among the street cooks than controls: cough (adjusted OR 4.4, 95% CI 2.2 to 8.5) and phlegm (adjusted OR 3.9, 95% CI 1.5 to 7.3). The street cooks also had higher odd of airway obstruction as measured by forced expiratory volume in 1 s/forced vital capacity <0.7: 11% 3% (adjusted OR of 3.3 (95% CI 1.3 to 8.7)). CONCLUSIONS: This study provides evidence of adverse respiratory effects among street cooks using biomass fuels.

Association between exercise-induced asthma and parental socio-economic status among school-aged adolescents in a semiurban community in Nigeria.

This study investigated the prevalence and association between exercise-induced asthma (EIA) and parental socio-economic status (PSES) among school-aged adolescents in a semiurban community in Nigeria. Three hundred and eighty-five adolescents (185 male and 200 female adolescents) whose ages ranged between 10 and 19 years participated in this cross-sectional study. Participants were recruited from four government approved secondary schools in Ido-Ekiti using a multistage sampling technique. Peak expiratory flow rate (PEFR) was assessed at baseline and after 6-min run test (6-MRT) on a level playing ground using a standard peak flow meter. PEFR measurements were repeated at 5th, 10th, 15th, and 20th min post 6-MRT. Participants who had >15.0% PEFR fall were considered to have EIA. PSES was assessed using a validated socio-economic status questionnaire. Descriptive and inferential statistics were used to analyze data. Alpha level was set at P<0.05. The mean ages of males and females were 13.9±2.0 and 13.8±1.6 years, respectively. More than half of the participants, 58.2% had EIA (>15.0% PEFR scores) while 53.5% belonged to middle PSES class. There was no significant difference between PEFR scores of male and female participants at baseline and 5th min post 6-MRT. However, male participants had significant higher PEFR than the female counterparts at 10th (t=2.090, P=0.037), 15th (t=2.162, P=0.031), and 20th min (t=2.978, P=0.003). There was significant association between EIA and PSES (χ2=152.4; P=0.001). The prevalence of EIA is very high among school-aged adolescents in Nigeria and was significantly associated with PSES.

Reduced Forced Vital Capacity in an African Population. Prevalence and Risk Factors.

RATIONALE: Black Africans have reduced FVC compared with white persons, but the prevalence and determinants of reduced values are not well understood. OBJECTIVES: To evaluate the prevalence and factors leading to reduced FVC in a Nigerian population and to examine current theories regarding the determinants of this difference. METHODS: We studied the ventilatory function of 883 adults aged 40 years or older participating in the Burden of Obstructive Lung Disease Study in Ile-Ife, Nigeria. Respondents completed pre- and post-bronchodilator spirometry test and provided information on their smoking history, respiratory symptoms, risk factors, and diagnoses, including anthropometric details. We used standard categories to define body mass index as either underweight, normal, overweight, or obese. We defined reduced FVC as a post-bronchodilator FVC below the lower limit of normal using National Health and Nutrition Examination Survey (NHANES) equations, Global Lung Function Initiative 2012 equations, and local reference equations based on nonsmoking study participants without a respiratory diagnosis. We fit multivariate linear regression models to FVC as a continuous measure, adjusting for age, sex, height, and other confounders. RESULTS: The prevalence of reduced FVC was 70.4% for men and 72.8% for women when using NHANES values for white Americans, 17.8% for men and 14.4% for women using NHANES equations for African Americans, and 15.5% for men and 20.5% for women using the Global Lung Function Initiative 2012 equations. Using the equations derived from nonsmoking respondents in the survey without a respiratory diagnosis, the prevalence of reduced FVC was less than 4% for both men and women. FVC was lower in participants who had less than 7 years of education (FVC, -96 ml; 95% confidence interval [CI], -172 to -19), were underweight (FVC, -269 ml; 95% CI, -464 to -73), were overweight (FVC, -132 ml; 95% CI, -219 to -46), and were obese (FVC, -222 ml; 95% CI, -332 to -112). CONCLUSIONS: There is a wide variation in the prevalence of reduced FVC based on the reference standard used. This variation is not satisfactorily explained by factors thought to affect FVC within individual populations. However, the prevalence strongly associates with both education level and body mass index in this population, regardless of the specific standard used.

A cross-sectional study with an improved methodology to assess occupational air pollution exposure and respiratory health in motorcycle taxi driving.

INTRODUCTION: Motorcycle taxi driving is common in many African cities. This study tested whether this occupation is associated with more respiratory disorders in a context of widespread urban air pollution with an improved methodology. METHODS: In a cross sectional study we compared 85 male motorcycle taxi drivers in the capital city of the Republic of Benin (Cotonou) with an age and neighborhood matched control group. All participants carried a portable carbon monoxide data logger for 8 hours per day to assess exposure to air pollution. Respiratory symptoms were obtained using a standardized questionnaire and pulmonary function was assessed by spirometry. RESULTS: The two groups did not differ significantly (p>0.10) in their age, height, educational level, and exposures to smoke from biomass fuels and tobacco products. The taxi drivers were exposed to higher mean (SD) levels of carbon monoxide (7.6±4.9ppmvs. 5.4±3.8ppm p=0.001). They reported more phlegm and tended to have slightly lower levels of lung function, although these differences were not statistically significant. CONCLUSION: In this cross sectional study of young motorcycle taxi drivers with substantial exposure to urban traffic and a matched control group, we found no evidence for respiratory impairment. A follow-up of such study population with other pollution exposure surrogate and other clinical endpoint may provide a more robust conclusion regarding the exposure response in this professional group.

Asthma in a university campus: a survey of students and staff of Obafemi Awolowo University, Ile-Ife, Nigeria.

BACKGROUND: Asthma continues to be an important cause of morbidity and mortality in developing countries. But, its burden among adult populations in university campuses is not well described. METHOD: Through a multistage cluster sampling of students and staff of the Obafemi Awolowo University, Ile-Ife, Nigeria, we obtained a representative sample, each for students and staff. We administered the European Community Respiratory Health Survey (ECRHS) screening questionnaire to all the respondents. A subgroup did a spirometry test and completed a detailed questionnaire. Asthma was considered "possible", if a respondent provided affirmative response to symptoms of "wheezing or whistling", "attack of shortness of breath", "diagnosed attack of asthma" in the last 12 months or "currently taking medicines for asthma". RESULTS: From population of 13,750 students and 1428 staff of the university, we systematically sampled 2750 (20%) students and all the staff. Amongst these, 2372 students and 455 staff completed the screening questionnaire. The mean age (SD) of the responders was 21.9 (3.2) and 46.1 (8.9) for students and staff and most of them were men; 58.6% and 65.9%, respectively. While an estimated 2.6% (95% CI: 1.7-3.5) of students had an asthma attack in the preceding 12 months, 14.5% (95% CI: 12.5-16.5) and 25.2% (95% CI: 22.8-27.7) reported shortness of breath and nocturnal cough, respectively. The staff population reported fewer symptoms. The proportion with "possible asthma" was 18.2% (95% CI: 16.0-20.4) for students and 8.0% (95% CI: 5.4-10.7) for staff. CONCLUSION: The prevalence of asthma is high among students and staff of Obafemi Awolowo University, Nigeria.

Low prevalence of asthma in sub Saharan Africa: a cross sectional community survey in a suburban Nigerian town.

BACKGROUND: Asthma remains an important cause of morbidity and mortality, especially in developing countries but the prevalence in Nigeria is not well described. METHODS: Using the European Community Respiratory Health Survey (ECRHS) standard screening questionnaire and asthma criteria, we recruited a representative sample of adults resident in a suburban community in Nigeria through a stratified three-stage cluster sampling technique. RESULTS: Out of a total of 3590 individuals contacted, 2310 responded and provided completed data (62.8% female). The prevalence of respiratory symptoms ranged from 0.4% (95% CI: 0.1-0.6) to 9.1% (95% CI: 7.6-10.6). Apart from nasal allergies, the most frequently reported symptoms were 'woken up by an attack of breathlessness at any time in the last 12 months' (2.4%, 95% CI: 1.8-3.0) and 'woken up by an attack of cough at any time in the last 12 months' (2.9%, 95% CI: 2.0-3.7). The combined proportion of respondents reporting previous asthma attack or currently taking asthma medication within the preceding 12 months (diagnosed asthma) was 1.5%, 95% CI: 1.0-2.0. The proportion with 'probable asthma' based on ECRHS criteria of any three symptoms of asthma (woken up by an attack of breathlessness or previous asthma attack or currently taking asthma medication within the preceding 12 months) was 3.1%, 95% CI: 2.0-4.3 for men and 3.3%, 95% CI: 2.4-4.2 for women. CONCLUSION: The prevalence of asthma in this suburban Nigerian population is low. Determinants of adult asthma distribution in low-income setting need further clarification.