Peak Expiratory Flow as a Surrogate for Health Related Quality of Life in Chronic Obstructive Pulmonary Disease: A Preliminary Cross Sectional Study

Background: Health Related Quality of Life (HRQL) measures can capture the non-respiratory effects of Chronic Obstructive Pulmonary Disease (COPD). However the relationship with Peak Expiratory Flow (PEF) is not well understoodAim: To determine the relationship of PEF and quality of life measurements in patients with COPD Settings and Design: A cross section of consecutive patients in a university clinicMethods: Stable patients with COPD defined by the Global Initiative on chronic Obstructive Lung Disease (GOLD) criteria, were recruited into the study. Spirometry was done using American Thoracic Society’s standards and  reference equations from African American norms of the US population. Quality of life was measured with the St George’s Respiratory Questionnaire (SGRQ)Results: Out of 50 patients recruited for the study, 48 provided complete data with acceptable spirometry and PEF data. The mean (SD) age and body mass index was 68.4 (8.9) years and 21.4 (4.6) kg/m2 respectively and 96% of the patients were in moderate-severe stages of COPD using the GOLD criteria. Percent predicted PEF correlated with percent predicted FEV1; r= 0.559 p<0.001 and also showed a significant, though moderate correlation between PEF readings and SGRQ scores especially in the activity (r= -0.455 p< 0.01) and total scores (r=-0.415 p<0.01) for pre bronchodilator (BD) percent predicted PEF. In regression analysis, PEF was associated with SGRQ (-0.11 95% CI -0.19, -0.03) after adjusting for age, sex, height, smoking and disease severityConclusions: PEF correlates with SGRQ scores and may be a useful surrogate for HRQL in patients with COPDKey words: Peak expiratory flow, quality of life, spirometry, primary car

Development of an international scale of socio-economic position based on household assets.

The importance of studying associations between socio-economic position and health has often been highlighted. Previous studies have linked the prevalence and severity of lung disease with national wealth and with socio-economic position within some countries but there has been no systematic evaluation of the association between lung function and poverty at the individual level on a global scale. The BOLD study has collected data on lung function for individuals in a wide range of countries, however a barrier to relating this to personal socio-economic position is the need for a suitable measure to compare individuals within and between countries. In this paper we test a method for assessing socio-economic position based on the scalability of a set of durable assets (Mokken scaling), and compare its usefulness across countries of varying gross national income per capita.Ten out of 15 candidate asset questions included in the questionnaire were found to form a Mokken type scale closely associated with GNI per capita (Spearmans rank rs = 0.91, p = 0.002). The same set of assets conformed to a scale in 7 out of the 8 countries, the remaining country being Saudi Arabia where most respondents owned most of the assets. There was good consistency in the rank ordering of ownership of the assets in the different countries (Cronbachs alpha = 0.96). Scores on the Mokken scale were highly correlated with scores developed using principal component analysis (rs = 0.977).Mokken scaling is a potentially valuable tool for uncovering links between disease and socio-economic position within and between countries. It provides an alternative to currently used methods such as principal component analysis for combining personal asset data to give an indication of individuals relative wealth. Relative strengths of the Mokken scale method were considered to be ease of interpretation, adaptability for comparison with other datasets, and reliability of imputation for even quite large proportions of missing values

Prevalence and burden of chronic bronchitis symptoms: results from the BOLD study

We studied the prevalence, burden and potential risk factors for chronic bronchitis symptoms in the Burden of Obstructive Lung Disease study. Representative population-based samples of adults aged ≥40 years were selected in participating sites. Participants completed questionnaires and spirometry. Chronic bronchitis symptoms were defined as chronic cough and phlegm on most days for ≥3 months each year for ≥2 years. Data from 24 855 subjects from 33 sites in 29 countries were analysed. There were significant differences in the prevalence of self-reported symptoms meeting our definition of chronic bronchitis across sites, from 10.8% in Lexington (KY, USA), to 0% in Ile-Ife (Nigeria) and Blantyre (Malawi). Older age, less education, current smoking, occupational exposure to fumes, self-reported diagnosis of asthma or lung cancer and family history of chronic lung disease were all associated with increased risk of chronic bronchitis. Chronic bronchitis symptoms were associated with worse lung function, more dyspnoea, increased risk of respiratory exacerbations and reduced quality of life, independent of the presence of other lung diseases. The prevalence of chronic bronchitis symptoms varied widely across the studied sites. Chronic bronchitis symptoms were associated with significant burden both in individuals with chronic airflow obstruction and those with normal lung function

Determinants of health related quality of life in a sample of patients with chronic obstructive pulmonary disease in Nigeria using the St. George’s respiratory questionnaire

Background: Chronic Obstructive Pulmonary Disease (COPD) is a multi-systemic and progressive disease. However the determinants of its impact on health related quality of life are not well-studied or understood in Nigeria. Objectives: To assess the determinants of health related quality of life in COPD Methods: Patients with stable COPD were recruited consecutively from the outpatient clinics of a university hospital. Health Related Quality of Life (HRQL) was assessed using the St. George’s Respiratory Questionnaire (SGRQ) and the Forced Expiratory Volume in one second (FEV1), Forced Vital Capacity (FVC) were measured by a vitalograph spirometer. Results: Fifty patients were recruited for this study (male= 60%). The mean (SD) age was 69 (9) years. The overall mean (SD)SGRQ scores was 45.9 (26.5), 50.6 (29.2), 29.7 (19.9), 38.8 (22.0) for the symptom, activity, impact and total scores respectively. After adjusting for age, sex and smoking, self-reported breathlessness independently predicted on average 25.2, 36.8, 13.65 and 22.9 points increase in SGRQ symptom, activity, impact and total scores respectively. Self-reported weight loss predicted 12.2 points increase in the impact subscale. Conclusions: Self-reported breathlessness and weight loss are independent predictors of low HRQL score in COPD

Chronic airflow obstruction in a Black African Population: results of BOLD study, Ile-Ife, Nigeria

Global estimates suggest that Chronic Obstructive Pulmonary Disease (COPD) is emerging as a leading cause of death in developing countries but there are few spirometry-based general population data on its prevalence and risk factors in sub-Saharan Africa. We used the Burden of Obstructive Lung Disease (BOLD) protocol to select a representative sample of adults aged 40 years and above in Ile-Ife, Nigeria. All the participants underwent spirometry and provided information on smoking history, biomass and occupational exposures as well as diagnosed respiratory diseases and symptoms. Chronic Airflow Obstruction (CAO) was defined as the ratio of post-bronchodilator (BD) one second Forced Expiratory Volume (FEV 1) to Forced Vital Capacity (FVC) below the lower limit of normal (LLN) of the population distribution for FEV 1/FVC. The overall prevalence of obstruction (post-BD FEV 1/FVC < LLN) was 7.7% (2.7% above LLN) using Global Lung Function Initiative (GLI) equations. It was associated with few respiratory symptoms; 0.3% reported a previous doctor-diagnosed chronic bronchitis, emphysema or COPD. Independent predictors included a lack of education (OR 2·5, 95% CI: 1.0, 6.4) and a diagnosis of either TB (OR 23.4, 95% CI: 2.0, 278.6) or asthma (OR 35.4, 95%CI: 4.9, 255.8). There was no association with the use of firewood or coal for cooking or heating. The vast majority of this population (89%) are never smokers. We conclude that the prevalence of CAO is low in Ile-Ife, Nigeria and unrelated to biomass exposure. The key independent predictors are poor education, and previous diagnosis of tuberculosis or asthma

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 DiseaseStudyinIle-Ife,Nigeria.Respondentscompletedpre-andpost- bronchodilator spirometry test and provided information on their smoking history, respiratory symptoms, risk factors, and diagnoses, including anthropometric details. We used standard categories to de fi ne body mass index as either underweight, normal, overweight, or obese. We de fi ned 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 fi t 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, 2 96 ml; 95% con fi dence interval [CI], 2 172 to 2 19), were underweight (FVC, 2 269 ml; 95% CI, 2 464 to 2 73), were overweight (FVC, 2 132 ml; 95% CI, 2 219 to 2 46), and were obese (FVC, 2 222 ml; 95% CI, 2 332 to 2 112). 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 speci fi c standard used

Prevalence of Malaria Parasitaemia in Adult HIV-Infected Patients in Jos, North-Central Nigeria

No Abstract

Unemployment in chronic airflow obstruction around the world: Results from the BOLD study

Objectives: We aimed to examine associations between chronic airflow obstruction (CAO) and unemployment across the world. Methods: Cross-sectional data from 26 sites in the Burden of Obstructive Lung Disease (BOLD) Study were used to analyze effects of CAO on unemployment. Odds ratios (OR) for unemployment in subjects 40-65 years old were estimated with multilevel mixed-effects generalized linear model with study site as random effect. Site-by-site heterogeneity was assessed using individual participant data meta-analyses. Results: Of 18710 participants, 11.3% had CAO. Ratio of unemployed subjects with CAO divided by subjects without CAO showed large site discrepancies, though these were no longer significant after adjusting for age, sex, smoking and education. Site-adjusted OR for unemployment (95%CI) was 1.79 (1.41, 2.27) for CAO cases, decreasing to 1.43 (1.14, 1.79) after adjusting for sociodemographic factors, comorbidities and forced vital capacity. Of other covariates that were associated with unemployment, age and education were important risk factors in high-income sites (OR (95%CI) 4.02 (3.53, 4.57) and 3.86 (2.80, 5.30) respectively), while female gender was important in low-to-middle-income sites (OR 3.23 (2.66, 3.91)). Conclusions: In the global BOLD study, CAO was associated with increased levels of unemployment, even after adjusting for sociodemographic factors, comorbidities and lung function

Unemployment in chronic airflow obstruction (CAO) around the world: results from the Burden of Obstructive Lung Disease (BOLD) study

Objectives: We aimed to examine associations between CAO and unemployment across the world. Methods: Cross-sectional data from 26 sites in the Burden of Obstructive Lung Disease (BOLD) Study were used to analyze effects of CAO on unemployment. Odds ratios (OR) for unemployment in subjects 40-65 years old were estimated with multilevel mixed-effects generalized linear model with study site as random effect. Site-by-site heterogeneity was assessed using individual participant data meta-analyses. Results: Of 18710 participants, 11.3% had CAO. Ratio of unemployed subjects with CAO divided by unemployed subjects without CAO showed large discrepancies between sites, particularly in low-to-middle income countries with ratio from 0.5 (lower unemployment among CAO cases) in the Philippines to 5.8 (higher unemployment among CAO cases) in India. Site-adjusted OR for unemployment (95% confidence interval) was 1.79 (1.41, 2.27) for participants with CAO, decreasing to 1.43 (1.14, 1.79) after adjusting for gender, age, smoking, comorbidities, education and forced vital capacity (FVC). Risk factors for unemployment in high-income sites were age (OR (95%CI) 4.02 (3.53, 4.57), and primary education vs university education 3.86 (2.80, 5.30). Female gender was the most important factor for unemployment in low-to-middle-income sites (OR 3.23 (2.66, 3.91). Conclusions: CAO was associated with unemployment even after adjusting for sociodemographic factors, comorbidities and FVC. We observed that the association was particularly strong in high-income sites

Airflow obstruction and use of solid fuels for cooking or heating: BOLD results

Rationale: Evidence supporting the association of COPD or airflow obstruction with use of solid fuels is conflicting and inconsistent. Objective: To assess the association of airflow obstruction with self-reported use of solid fuels for cooking or heating. Methods: We analysed 18,554 adults from the BOLD study, who had provided acceptable post-bronchodilator spirometry measurements and information on use of solid fuels. The association of airflow obstruction with use of solid fuels for cooking or heating was assessed by sex, within each site, using regression analysis. Estimates were stratified by national income and meta-analysed. We carried out similar analyses for spirometric restriction, chronic cough and chronic phlegm. Measurements and main results: We found no association between airflow obstruction and use of solid fuels for cooking or heating (ORmen=1.20, 95%CI 0.94-1.53; ORwomen=0.88, 95%CI 0.67-1.15). This was true for low/middle and high income sites. Among never smokers there was also no evidence of an association of airflow obstruction with use of solid fuels (ORmen=1.00, 95%CI 0.57-1.76; ORwomen=1.00, 95%CI 0.76-1.32). Overall, we found no association of spirometric restriction, chronic cough or chronic phlegm with the use of solid fuels. However, we found that chronic phlegm was more likely to be reported among female never smokers and those who had been exposed for ≥20 years. Conclusion: Airflow obstruction assessed from post-bronchodilator spirometry was not associated with use of solid fuels for cooking or heating