Am. J. Respir. Crit. Care Med., Vol 150, No. 2, 08 1994, 348-355.
Review and analysis of variation between spirometric values reported in 29 studies of healthy African adults
NW White, JH Hanley, UG Lalloo and MR Becklake
Department of Epidemiology and Biostatistics, McGill University, Montreal, Canada.
Within- and between-population variation in spirometric measurements has
been addressed in a systematic review of spirometric measurements from 29
studies published between 1965 and 1990 involving 9,690 men and 2,638 women
of sub-Saharan African ancestry; FVC and FEV1 were age- and
height-standardized at BTPS. Between- population differences were related
to geographic region and sample source (workforce versus community). The
effects of altitude, variation in sample mean height, and year of study
publication were also significant variables in multivariate models
explaining between-population differences. Altitude was the most important
variable with an effect of 263 ml/1,000 m (95% confidence interval [CI]
120-410) on FVC in men. In women, variation in sample mean height was also
important, with taller populations having larger values for FVC (64 ml/cm).
In men, secular trends were evident, with date of study associated with
negative trends among men in the U.S.A. (-35.3 ml/year), and positive
trends (14.7 ml/year) in other regions. These differences in trend could
not be explained. Population selection factors, altitude, date of study,
and other biological sources of variation need to be taken into account in
evaluating between- and within-population comparisons of spirometric
measurements.
