Multi-ethnic reference values for spirometry for the 3–95-yr age range: the global lung function 2012 equations

Abstract

Objective Derive continuous prediction equations and their lower limits of normal for spirometric indices, which are applicable globally. Material Over 160,000 data points from 72 centres in 33 countries were shared with the European Respiratory Society Global Lung Function Initiative. Eliminating data that could not be used (mostly missing ethnic group, some outliers) left 97,759 records of healthy nonsmokers (55.3% females) aged 2.5–95 years. Methods Lung function data were collated, and prediction equations derived using the LMS (λ, µ, σ) method, which allows simultaneous modelling of the mean (mu), the coefficient of variation (sigma) and skewness (lambda) of a distribution family. Results After discarding 23,572 records, mostly because they could not be combined with other ethnic or geographic groups, reference equations were derived for healthy individuals from 3–95 years for Caucasians (N=57,395), African Americans (N=3,545), and North (N=4,992) and South East Asians (N=8,255). FEV1 and FVC between ethnic groups differed proportionally from that in Caucasians, such that FEV1/FVC remained virtually independent of ethnic group. For individuals not represented by these four groups, or of mixed ethnic origins, a composite equation taken as the average of the above equations is provided to facilitate interpretation until a more appropriate solution is developed. Conclusion Spirometric prediction equations for the 3–95 age range are now available that include appropriate age-dependent lower limits of normal. They can be applied globally to different ethnic groups. Additional data from the Indian subcontinent, Arab, Polynesian, Latin American countries, and Africa will further improve these equations in the future.

Seven‐year safety and efficacy with velaglucerase alfa for treatment‐naïve adult patients with type 1 Gaucher disease

“…Echocardiography and PFTs, undertaken to rule out possible onset of pulmonary hypertension 13, 14, revealed no pathology or safety concerns throughout the observation period and mean values remained within the normal range for age, ethnicity, and height 15.…”

“…At the time of initiation of this trial, there was concern about the possibility of either primary‐like 13 or secondary 14 pulmonary hypertension among patients with GD who may have been respectively treated with imiglucerase 13 or insufficiently treated with imiglucerase 14. Beyond the very mild natural diminution because of age in PFTs 15, there was no clinical evidence of pulmonary hypertension following prolonged exposure to velaglucerase alfa.…”

Determinants of persistent asthma in young adults

“…combined with asthma-like symptoms, use of medication for breathing within the last 12 months or airflow obstruction according to a modified definition used by de Marco et al in a recent study [18] (Table S1). Obstruction was defined according to the lower limit of normal (LLN) [19] i.e. the 5th percentile of FEV₁/FVC distribution corresponding to a z-score <−1.64.…”

“…The bronchodilation was positive with an increase in FEV₁ of ≥12% and ≥200 ml. FEV₁ below predicted was defined by FEV₁<100% predicted corresponding to a z-score<0 [19]. Atopy was defined by one or more positive SPT (mean wheal diameter ≥3 mm).…”

Defining and grading an obstructive ventilatory defect (OVD): ‘FEV1/FVC lower limit of normal (LLN) vs. Z-score’ and ‘FEV1 percentage predicted (%pred) vs. Z-score’

“…<lower limit of normal (LLN)] [1,2]. In practice, once the OVD diagnosis is retained, it is essential to grade its severity into five degrees based on the FEV 1 [1,3].…”