Effects of aging on lung function. A comparison of lung function in healthy adults and the elderly

The respiratory system changes with age and understanding these changes helps detect and prevent respiratory dysfunctions in the elderly.

This study compares the respiratory pattern in healthy non-smoker adults and the elderly, using lung function testing and expansion of the chest to confirm the effects of aging on lung function.

We used lung function testing to measure forced vital capacity, forced expiratory volume in one second, peak expiratory flow rate and maximum voluntary ventilation. We also measured expansion of the chest. Measurements were taken with subjects resting in the dorsal recumbent position with upper body elevated to 45 masculine. Statistical analysis consisted of the Student T test for independent samples, the non-parametric Mann-Whitney test with a p <0.05 level, and linear regression analysis, also with a p <0.05 level, to assess correlation between variables studied and age. Our population consisted of 35 elderly subjects and 35 adults. 15 of the elderly subjects were male (43%) and 20 female (57%). 16 of the adult group were male (46%) and 19 female (54%). The sample was mapped in terms of age, weight, height, abdominal girth and clinical data, to exclude factors which could distort the results.

The difference between the two study groups attained statistical significance for all parameters measured. The linear relationship was also significant between age and all parameters and a negative and significant correlation was seen. Expansion of the chest in females was the parameter most inversely correlated with age (60.37%). The lung function testing variable with the greatest difference between the groups was peak expiratory flow rate (35.77% in females and 36.17% in males).

Our results show differences in the respiratory patterns of healthy adults and the elderly, suggesting that age impacts on lung function. Both male and female elderly subjects had lower lung function testing scores than the adult subjects, with this difference more marked in females.