METHODS: In an international, community-based prospective study, we enrolled individuals from communities in 17 countries between Jan 1, 2005, and Dec 31, 2009 (except for in Karnataka, India, where enrolment began on Jan 1, 2003). Trained local staff obtained data from participants with interview-based questionnaires, measured weight and height, and recorded forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC). We analysed data from participants 130-190 cm tall and aged 34-80 years who had a 5 pack-year smoking history or less, who were not affected by specified disorders and were not pregnant, and for whom we had at least two FEV₁ and FVC measurements that did not vary by more than 200 mL. We divided the countries into seven socioeconomic and geographical regions: south Asia (India, Bangladesh, and Pakistan), east Asia (China), southeast Asia (Malaysia), sub-Saharan Africa (South Africa and Zimbabwe), South America (Argentina, Brazil, Colombia, and Chile), the Middle East (Iran, United Arab Emirates, and Turkey), and North America or Europe (Canada, Sweden, and Poland). Data were analysed with non-linear regression to model height, age, sex, and region.
FINDINGS: 153,996 individuals were enrolled from 628 communities. Data from 38,517 asymptomatic, healthy non-smokers (25,614 women; 12,903 men) were analysed. For all regions, lung function increased with height non-linearly, decreased with age, and was proportionately higher in men than women. The quantitative effect of height, age, and sex on lung function differed by region. Compared with North America or Europe, FEV1 adjusted for height, age, and sex was 31·3% (95% CI 30·8-31·8%) lower in south Asia, 24·2% (23·5-24·9%) lower in southeast Asia, 12·8% (12·4-13·4%) lower in east Asia, 20·9% (19·9-22·0%) lower in sub-Saharan Africa, 5·7% (5·1-6·4%) lower in South America, and 11·2% (10·6-11·8%) lower in the Middle East. We recorded similar but larger differences in FVC. The differences were not accounted for by variation in weight, urban versus rural location, and education level between regions.
INTERPRETATION: Lung function differs substantially between regions of the world. These large differences are not explained by factors investigated in this study; the contribution of socioeconomic, genetic, and environmental factors and their interactions with lung function and lung health need further clarification.
FUNDING: Full funding sources listed at end of the paper (see Acknowledgments).
RESULTS: No significant difference in plasma propranolol (mean +/- SEM) levels was seen between races six hours after the last dose (Malays, 59.7 +/- 8.8 ng/ml, Indians, 67.6 +/- 19.3 ng/ml, Chinese, 58.4 +/- 7.9 ng/ml). Chinese were least sensitive to the bradycardic and hypotensive effects of propranolol at rest and exercise. Indians and Malays had significant reduction of supine systolic blood pressure with propranolol but not Chinese. Comparison of percentage reductions of systolic blood pressure at supine, sitting and exercise by repeated measure analysis showed the Malays to have significantly higher change compared to the Chinese (p = 0.022). Similarly, comparison of percentage reductions of heart rate at supine, sitting and exercise by repeated measure analysis showed the Malays to have significantly higher change compared to the Chinese (p = 0.040). Average change in potassium concentrations at peak exercise and recovery showed the Indians to have significantly higher increase in potassium levels with propranolol compared to the Malays (p = 0.038). However, no significant interethnic difference was seen in the reduction of glucose levels at rest, peak exercise or recovery. Also, no significant interethnic difference was seen in reduction of FEV1 values.
CONCLUSION: We, therefore, conclude that ethnic differences in response to blockade of beta-receptors exist among racial groups in Malaysia. These differences were seen at similar plasma drug levels between races suggesting ethnic differences in drug sensitivity, rather than differences in drug disposition.
METHODS: This cross-sectional study was conducted at Hospital Tuanku Fauziah, Perlis, Malaysia from August 2015 to April 2016. FEV1/FEV6 and FEV1/FVC results of 117 subjects were analysed. Demographic data and spirometric variables were tabulated. A scatter plot graph with Spearman's correlation was constructed for the correlation between FEV1/FEV6 and FEV1/FVC. The sensitivity, specificity, positive and negative predictive values of FEV1/FEV6 were determined with reference to the gold standard of FEV1/FVC ratio <0.70. Receiver-operator characteristic (ROC) curve analysis and Kappa statistics were used to determine the FEV1/FEV6 ratio in predicting an FEV1/FVC ratio <0.70.
RESULTS: Spearman's correlation with r = 0.636 (P<0.001) was demonstrated. The area under the ROC curve was 0.862 (95% confidence interval [CI]: 0.779 - 0.944, P<0.001). The FEV1/FEV6 cut-off with the greatest sum of sensitivity and specificity was 0.75. FEV1/FEV6 sensitivity, specificity, positive and negative predictive values were 93.02%, 67.74%, 88.89% and 77.78% respectively. There was substantial agreement between the two diagnostic cut-offs (κ = 0.634; 95% CI: 0.471 - 0.797, P<0.001) CONCLUSIONS: The FEV1/FEV6 ratio can be considered to be a good alternative to the FEV1/FVC ratio for screening of COPD. Larger multicentre study and better education on spirometric techniques can validate similar study outcome and establish reference values appropriate to the population being studied.
METHODS: In this international, community-based cohort study, we prospectively enrolled adults aged 35-70 years who had no intention of moving residences for 4 years from rural and urban communities across 17 countries. A portable spirometer was used to assess FEV1. FEV1 values were standardised within countries for height, age, and sex, and expressed as a percentage of the country-specific predicted FEV1 value (FEV1%). FEV1% was categorised as no impairment (FEV1% ≥0 SD from country-specific mean), mild impairment (FEV1% <0 SD to -1 SD), moderate impairment (FEV1%
METHODS: The Norfolk (UK) based European Prospective Investigation into Cancer (EPIC-Norfolk) recruited 25,639 participants between 1993 and 1997. FEV1 measured by portable spirometry, was categorized into sex-specific quintiles. Mortality and morbidity from all causes, cardiovascular disease (CVD) and respiratory disease were collected from 1997 up to 2015. Cox proportional hazard regression analysis was used with adjustment for socio-economic factors, physical activity and co-morbidities.
RESULTS: Mean age of the population was 58.7 ± 9.3 years, mean FEV1 for men was 294± 74 cL/s and 214± 52 cL/s for women. The adjusted hazard ratios for all-cause mortality for participants in the highest fifth of the FEV1 category was 0.63 (0.52, 0.76) for men and 0.62 (0.51, 0.76) for women compared to the lowest quintile. Adjusted HRs for every 70 cL/s increase in FEV1 among men and women were 0.77 (p < 0.001) and 0.68 (p < 0.001) for total mortality, 0.85 (p<0.001) and 0.77 (p<0.001) for CVD and 0.52 (p <0.001) and 0.42 (p <0.001) for respiratory disease.
CONCLUSIONS: Participants with higher FEV1 levels had a lower risk of CVD and all-cause mortality. Measuring the FEV1 with a portable handheld spirometry measurement may be used as a surrogate marker for cardiovascular risk. Every effort should be made to identify those with poorer lung function even in the absence of cardiovascular disease as they are at greater risk of total and CV mortality.