Applicability of the Global Lung Initiative 2012 Reference Values for Spirometry for Longitudinal Data of Elderly Women.
ABSTRACT: BACKGROUND AND OBJECTIVES:Lung function depends nonlinearly on age and height, so that the use of age and height specific reference values is required. The widely used age and height specific GLI (Global Lung Initiative) z-scores derived from cross-sectional data, however, have not been proven for validity in an elderly population or for longitudinal data. Therefore, we aimed to test their validity in a population of elderly women followed prospectively for more than 20 years. METHODS:We used spirometric data (forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) and FEV1/FVC) from the SALIA cohort of German women (baseline: 1985-1994 (aged 55 years), follow-up: 2008/2009 and 2012/2013). We calculated GLI-z-scores for baseline and follow-up examination separately (cross-sectional evaluation) and individual differences in z-scores between baseline and follow-up (longitudinal evaluation) for healthy never-smoking women. RESULTS:GLI reference values for FEV1, FVC and FEV1/FVC were cross-sectionally and longitudinally equivalent with our SALIA data. The mean change in z-scores between baseline and follow-up was 0.33 for FEV1, 0.38 for FVC and -0.10 for FEV1/FVC. CONCLUSIONS:In conclusion, GLI z-scores fit cross-sectionally and longitudinally with FEV1, FVC and FEV1/FVC measured in women from Germany which indicates that they can be used in longitudinal association analyses.
Project description:BACKGROUND:The validation of the multi-ethnic GLI-2012 spirometric norms has been debated in several countries. However, its applicability in Algeria has not been verified. AIM:To ascertain how well the GLI-2012 norms fit contemporary adult Algerian spirometric data. METHODS:This was a cross-sectional study of a convenience sample of 300 healthy non-smoker adults (50% men, age range: 18-85 years) recruited from the Algiers region general population. All participants underwent a clinical examination and a plethysmography measurement. Z-scores for some spirometric data [FEV1, FVC, FEV1/FVC and forced expiratory flow at 25-75% of FVC (FEF25-75%)] were calculated. If the average Z-score deviated by "< ± 0.5" from the overall mean, the GLI-2012 norms would be considered as reflective of contemporary Algerian spirometry. RESULTS:The means±SDs of age, height, weight, FVC, FEV1, FEV1/FVC and FEF25-75% of the participants were, respectively, 48±17 years, 1.65±0.10 m, 73±14 kg, 4.04±1.04 L, 3.18±0.82 L, 0.79±0.05 and 4.09±1.09 L/s. Almost the quarter of participants were obese. The total sample means±SDs Z-scores were 0.22±0.87 for FVC, 0.04±0.88 for FEV1, -0.34±0.67 for FEV1/FVC and 0.93±0.79 for FEF25-75%. For men and women, only the means±SDs of the FEF25-75% Z-scores exceeded the threshold of "± 0.5", respectively, 1.13±0.77 and 0.73±0.76. CONCLUSION:Results of the present study, performed in an Algerian population of healthy non-smoking adults, supported the applicability of the GLI-2012 norms to interpret FEV1, FVC and FEV1/FVC but not the FEF25-75%.
Project description:Spirometry reference values specifically designed for Asian Americans are currently unavailable. The performance of Global Lung Function Initiative 2012 (GLI-2012) equations on assessing spirometry in Asian Americans has not been evaluated. This study aimed to assess the fitness of relevant GLI-2012 equations for spirometry in Asian Americans.Asian subjects who never smoked and had qualified spirometry data were extracted from the National Health and Nutrition Examination Survey (NHANES) 2011-2012. Z-scores of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1/FVC were separately constructed with GLI-2012 equations for North East (NE) Asians, South East (SE) Asians, and individuals of mixed ethnic origin (Mixed). In addition, Proportions of subjects with observed spirometry data below the lower limit of normal (LLN) were also evaluated on each GLI-2012 equation of interest.This study included 567 subjects (250 men and 317 women) aged 6-79 years. Spirometry z-scores (z-FEV1, z-FVC, and z-FEV1/FVC) based on GLI-2012 Mixed equations had mean values close to zero (-?0.278 to -?0.057) and standard deviations close to one (1.001 to 1.128); additionally, 6.0% (95% confidence interval (CI) 3.1-8.9%) and 6.4% (95% CI 3.7-9.1%) of subjects were with observed data below LLN for FEV1/FVC in men and women, respectively. In contrast, for NE Asian equations, all mean values of z-FEV1 and z-FVC were smaller than -?0.5; for SE Asian equations, mean values of z-FEV1/FVC were significantly smaller than zero in men (-?0.333) and women (-?0.440).GLI-2012 equations for individuals of mixed ethnic origin adequately fitted spirometry data in this sample of Asian Americans. Future studies with larger sample sizes are needed to confirm these findings.
Project description:Introduction: The purpose of the study was to establish spirometric reference values for a Central Asian population of highlanders and lowlanders. Methods: Spirometries from a population-based cross-sectional study performed in 2013 in rural areas of Kyrgyzstan were analyzed. Using multivariable linear regression, Global Lung Function Initiative (GLI) equations were fitted separately for men and women, and altitude of residence (700-800 m, 1,900-2,800 m) to data from healthy, never-smoking Kyrgyz adults. The general GLI equation was applied: Predicted value=ea0+a1× ln(Height)+a2× ln(Age)+b1× ln(Age100)+b2× ln(Age100)2+b3× ln(Age100)3 +b4× ln(Age100)4+b5× ln(Age100)5 Results: Of 2,784 screened Kyrgyz, 448 healthy, non-smoking highlanders (379 females) and 505 lowlanders (368 females), aged 18-91 years, were included. Predicted FVC in Kyrgyz fit best with GLI "North-East Asians," predicted FEV1 fit best with GLI "Other/Mixed." Predicted FEV1/FVC was lower than that of all GLI categories. Age- and sex-adjusted mean FVC and FEV1 were higher in highlanders (+0.138l, +0.132l) than in lowlanders (P < 0.001, all comparisons), but FEV1/FVC was similar. Conclusion: We established prediction equations for an adult Central Asian population indicating that FVC is similar to GLI "North-East Asian" and FEV1/FVC is lower than in all other GLI population categories, consistent with a relatively smaller airway caliber. Central Asian highlanders have significantly greater dynamic lung volumes compared to lowlanders, which may be due to environmental and various other effects.
Project description:We aimed to assess the validity of using the Global Lung Function Initiative's (GLI) 2012 equations to interpret lung function data in a healthy workforce of South Australian Metropolitan Fire Service (SAMFS) personnel.Spirometry data from 212 healthy, nonsmoking SAMFS firefighters were collected and predicted normal values were calculated using both the GLI and local population derived (Gore) equations for forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC. Two-tailed paired sample Student's t-tests, Bland-Altman assessments of agreement, and z-scores were used to compare the two prediction methods.The equations showed good agreement for mean predicted FEV1, FVC, and FEV1/FVC. Mean z-scores were similar for FEV1 and FVC, although not FEV1/FVC, but greater than 0.5. Differences between the calculated lower limits of normal (LLN) were significant (p < 0.01), clinically meaningful, and resulted in an 8% difference in classification of abnormality using the FEV1/FVC ratio.The GLI equations predicted similar lung function as population-specific equations and resulted in a lower incidence of obstruction in this sample of healthy SAMFS firefighters. Further, interpretation of spirometry data as abnormal should be based on both an FEV1 and FEV1/FVC ratio < LLN.
Project description:METHODS:Spirometry datasets from South-Asian children were collated from four centres in India and five within the UK. Records with transcription errors, missing values for height or spirometry, and implausible values were excluded(n = 110). RESULTS:Following exclusions, cross-sectional data were available from 8,124 children (56.3% male; 5-17 years). When compared with GLI-predicted values from White Europeans, forced expired volume in 1s (FEV1) and forced vital capacity (FVC) in South-Asian children were on average 15% lower, ranging from 4-19% between centres. By contrast, proportional reductions in FEV1 and FVC within all but two datasets meant that the FEV1/FVC ratio remained independent of ethnicity. The 'GLI-Other' equation fitted data from North India reasonably well while 'GLI-Black' equations provided a better approximation for South-Asian data than the 'GLI-White' equation. However, marked discrepancies in the mean lung function z-scores between centres especially when examined according to socio-economic conditions precluded derivation of a single South-Asian GLI-adjustment. CONCLUSION:Until improved and more robust prediction equations can be derived, we recommend the use of 'GLI-Black' equations for interpreting most South-Asian data, although 'GLI-Other' may be more appropriate for North Indian data. Prospective data collection using standardised protocols to explore potential sources of variation due to socio-economic circumstances, secular changes in growth/predictors of lung function and ethnicities within the South-Asian classification are urgently required.
Project description:A hallmark of the newly published GLI (Global Lungs Initiative) spirometric reference values is their "all-age" (3-95yr) predictive power, accomplished by incorporating non-linear age dependencies into modelling parameters. This modelling strategy is especially promising for the age range of puberty; however, the performance of GLI-values for adolescents is currently unknown. We calculated GLI-based z-scores for children/adolescents without apparent respiratory diseases from two different German studies, LUNOKID (N = 1943, 4-19 years) and GINIplus (N = 1042, 15 years) and determined the goodness of fit for specific age groups. We defined fit sufficient if the absolute mean of z-scores was <0.5. For children (<10yr) the mean GLI-based z-scores for FEV1 and FVC reached a good fit with mean z-scores for FEV1 between -0.11 and 0.01 and mean z-scores for FVC between 0.01 and 0.16, but larger deviations were observed in adolescents, especially boys (mean z-score -0.58 for FEV1 and -0.57 for FVC in GINIplus). The fit for FEV1/FVC was sufficient. GLI reference values provided reasonable estimates for the individuals enrolled in our studies, which span the age range of lung growth and development. However, we found that GLI-predictions overestimated lung volumes, especially those for German adolescent boys, which may, left unrecognised, lead to erroneous diagnosis of lung disease. Caution should be taken when applying these reference values to epidemiologic studies.
Project description:Background and objective:This study aimed to establish reference equations for spirometry in healthy Taiwanese children and assess the applicability of the Global Lung Function Initiative (GLI)-2012 equations to Taiwanese children. Methods:Spirometric data collected from 757 healthy Taiwanese children aged 5 to 18 years in a population-based cohort study. Prediction equations derived using linear regression and the generalized additive models for location, scale and shape (GAMLSS) method, respectively. Results:The GLI-2012 South East Asian equations did not provide a close fit with mean ± standard error z-scores of -0.679 ± 0.030 (FVC), -0.186 ± 0.044 (FEV1), -0.875 ± 0.049 (FEV1/FVC ratio) and -2.189 ± 0.063 (FEF25-75) for girls; and 0.238 ± 0.059, -0.061 ± 0.053, -0.513 ± 0.059 and -1.896 ± 0.077 for boys. The proposed GAMLSS models took age, height, and weight into account. GAMLSS models for boys and girls captured the characteristics of spirometric data in the study population closely in contrast to the linear regression models and the GLI-2012 equations. Conclusion:This study provides up-to-date reference values for spirometry using GAMLSS modeling in healthy Taiwanese children aged 5 to 18 years. Our study provides evidence that the GLI-2012 reference equations are not properly matched to spirometric data in a contemporary Taiwanese child population, indicating the urgent need for an update of GLI reference values by inclusion of more data of non-Caucasian decent.
Project description:BACKGROUND:Although the prevalence of kidney disease is higher in those with reduced lung function, the longitudinal relationship between low lung function and future risk of chronic kidney disease (CKD) has not been widely explored. METHODS:Baseline lung function was assessed in 20,700 men and 7325 women from 1974 to 1992. Mean age was 43.4 (±6.6) and 47.5 (±7.9) for men and women respectively. Sex-specific quartiles of FEV1 and FVC (L) were created (Q4: highest, reference) and the cohort was also divided by the FEV1/FVC ratio (? or?<?0.70). Cox proportional hazards regression was used to determine the risk of incident CKD events (inpatient or outpatient hospital diagnosis of CKD) in relation to baseline lung function after adjustment for various confounding factors. RESULTS:Over 41?years of follow-up there were 710 and 165 incident CKD events (main diagnosis) in men and women respectively. Low FEV1 was strongly associated with future risk of CKD in men (Q1 vs Q4 adjusted HR: 1.46 (CI:1.14-1.89), p-trend 0.002). Similar findings were observed for FVC in men (1.51 (CI:1.16-1.95), p-trend 0.001). The adjusted risks were not found to be significant in women, for either FEV1 or FVC. FEV1/FVC?<?0.70 was not associated with increased incidence of CKD in men or women. CONCLUSION:Low FEV1 and FVC levels at baseline are a risk factor for the development of future incident CKD in men. Monitoring kidney function in those with reduced vital capacity in early life could help with identifying those at increased risk of future CKD.
Project description:The aim of this study was to assess the association of key adiposity markers with lung function in smokers without respiratory disease in a Mediterranean population.We performed a cross-sectional study with baseline data from a representative sample of the ESPITAP study in Spain. Participants were 738 smokers (52.3% men) without respiratory disease, aged 35 to 70, selected from 12 primary health care centres. We assessed weight, height, body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR). The pulmonary functional parameters were forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and FEV1/FVC ratio.In this cohort of smokers, 22.2% of individuals had central obesity. FVC% was inversely associated with all anthropometric measures (BMI, WC and WHtR) in the overall population and in men; in women, only BMI was associated with FVC%. FEV1% was inversely associated to BMI and WC in the overall population, and to all anthropometric measures in men. Furthermore, both BMI and obesity were positively associated with FEV1/FVC ratio overall and when stratified by sex; this suggests a restrictive pattern explained by the altered ventilator mechanics experienced by people with obesity.In a Mediterranean population of smokers without respiratory symptoms, abdominal obesity, evaluated not only by BMI and WC but also WHtR, is inversely associated with lung function. Fat distribution appears more strongly related to pulmonary function parameters in men than in women. In smokers with high values for WC, WHtR and BMI, assessment of lung function is recommended.Current Controlled Trials NCT01194596 . Registered 2 September 2010.
Project description:The dose-response relationship between glycemic status and lung function has not been thoroughly investigated. We hypothesized that there are continuous and inverse associations between glycemic measures and lung function tests and examined the hypothesis in Japanese adults.We cross-sectionally investigated associations of hemoglobin A1c (HbA1c) and fasting plasma glucose (FPG) with forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) in 3161 adults who participated in a health screening from 2008 to 2011. The study participants included both diabetic and non-diabetic adults. Multiple linear regression analyses were performed to examine the associations.Inverse associations were observed in both sexes, which were attenuated in women after adjustment for multiple variables. A 1% absolute increase in HbA1c was associated with a -52-mL (95% confidence interval [CI] -111 to 8 mL) difference in FVC and a -25-mL (95% CI -75 to 25 mL) difference in FEV1 in women, and a -128-mL (95% CI -163 to -94 mL) difference in FVC and a -73-mL (95% CI -101 to -44 mL) difference in FEV1 in men. A 10-mg/dL increase in FPG was associated with a -11-mL (95% CI -29 to 8 mL) difference in FVC and a -8-mL (95% CI -24 to 7 mL) difference in FEV1 in women, and a -32-mL (95% CI -44 to -21 mL) difference in FVC and a -19-mL (95% CI -28 to -9 mL) difference in FEV1 in men.Inverse associations between glycemic measures and lung function were observed. Men seem more susceptible to the alteration in FVC and FEV1 than women.