Pulmonary function studies in healthy non-smoking adults in Sri Aurobindo Ashram, Pondicherry

Pulmonary functions are used for diagnosis, assessment and clinical management of breathlessness, and, as epidemiological and research tools. In India the wide range of geographical and climatic conditions is associated with regional differences in lung functions. Most of the studies have restricted themselves to specific regions/ethnicities and a relatively short age span of 15-40 yr. The purpose of the present study is to fill these two lacunae by studying the pulmonary functions of the inmates (17-70 yr and of different ethnicities) of Sri Aurobindo Ashram, Pondicherry.

A total of 397 non-smoking, healthy individuals aged 17 to 70 yr (195 men, 202 women) were investigated. The parameters measured included forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1, FEV1%), peak expiratory flow rate (PEF) and mean expiratory flow rate (MEF). The standing height and weight were also recorded.

In both men and women, age showed significant negative correlations with all spirometric functions, the height showed significant positive correlations with all pulmonary function test (PFT) parameters except FEV1 per cent while the weight did not show any significant correlation with any of the parameters except PEF. Men had significantly (P < 0.001) higher values than those of women for all parameters except FEV1 per cent. Prediction equations for all PFT parameters based on the age and height were derived for men and women.

The ventilatory norms of both men and women based on age and height appear reliable for the FVC and FEV1. They can therefore be used to derive the normal values for healthy, non-smoking Indian adults between 17 and 70 yr. The coefficient for age obtained from the regression equations for FVC were found to be consistently smaller than those of others indicating that in the Ashram environment, age seems to have a lesser negative influence on pulmonary functions.