Lung Function Reference Values in Chinese Children and Adolescents in Hong Kong

Abstract

As part of a comprehensive evaluation of lung function in Hong Kong-born Chinese children and adolescents, this study was conducted to determine updated prediction equations for spirometry, to evaluate the secular changes of lung function during the past decade, and to compare these results with other data sets. The results are based on 852 (392 male, 460 female) healthy students, age 7 to 19 yr, recruited from seven schools in Hong Kong. All were born and lived in Hong Kong, nonsmokers, free from past or present symptoms or diseases affecting the respiratory tract. A body plethysmograph was used to record lung function measurements. Natural logarithmic values of lung volumes and body height were used in the final regression model. Prediction equations for FVC, FEV(1), and maximal expiratory flow at 50% of the FVC (MEF(50)) for both sexes are presented, with standing height as the dependent variable. Compared with Hong Kong data from 1985, the results show a significant increase in height-corrected FVC and FEV(1) in both boys and girls, over the whole height range. Compared with recent data of whites, FVC in boys were 8 to 10% lower in the study population, and the difference increased to 12% above the 165 cm height ranges, while FVC in Chinese girls had similar or only slightly lower predicted values. FEV(1) values showed a similar pattern with lesser difference between the two ethnic groups. Compared with recent data from Chinese children in Singapore, a similar pattern with overall lesser difference of the two populations was present in boys, whereas there was no significant difference between girls in the two places. Our findings support the conclusion that exogenous factors may contribute significantly to the differences in lung function values among ethnic groups and that it is important to examine normative values of various populations for secular trends.

Spirometric Reference Values in Tunisian Children

“…Our regression equation used a single function – ln (height). These results were similar to those described elsewhere [13,14,15,16,17,18]. Our lung function values have the advantage of being derived from a large base, uniformly collected with exactly the same equipment and criteria for inclusion.…”

“…Lung function is known to vary with ethnicity, and it is therefore important to establish special reference values relevant to the ethnic group of the local population [5,6,7,8,9,10,11,12,13,14,15,16,17,18]. In contrast to genetic constitution, environmental factors affecting growth and development such as child health nutritional status and air quality may change over long periods of time [19], and therefore lung function values for a given ethnic community may change over time.…”

“…Various multiple prediction equations for spirometric parameters were applied to the series over all ages examined, and the final selected one was the standard regression model used by many authors [7,8,9,10,11,12,13]. This model includes the logarithmic values of both function values and body height.…”

“…The aims of this study were (1) to measure some pulmonary function parameters in healthy Tunisian children aged 6–16 years, (2) to establish normal spirometric values and (3) to compare these data with those of similar groups of European [9], white US [10], Libyan [12] and Asian [13] children.…”

Analysis of Growth Factors and Inflammatory Cytokines in Exhaled Breath Condensate from Asthmatic Children

“…All subjects underwent spirometric assessment (Model 2130, Vitalograph, Buckingham, UK) to measure FEV 1 and FVC, and results were compared to local reference values [25]. …”