Abstract
Objective: Chronic obstructive pulmonary disease is often present in elderly Japanese. The aim of this retrospective cohort study was to assess the predictive factors of chronic obstructive pulmonary disease in Japanese subjects.
Methods: A total of 1336 men and women examined annually from 1997 to 2006 in our health check-up division by means of the respiratory function test were enrolled. The average decrease in FEV1.0 based on several factors was evaluated using the Mann-Whitney test or Kruskal-Wallis test.
Results: The total average decrease in FEV1.0 was -0.38L. The average decrease in males was significantly larger than in females (-0.40L and -0.32L, respectively). As for differences among age groups, the decrease from the 1997 average for subjects over 55(-0.36L) was significantly smaller than that for under 45(-0.39L) and between 45 and 55(-0.39L). The average decrease in FEV1.0 for subjects with a BMI between 20 and 25 was significantly larger than for subjects with a BMI of less than 20 and those with a BMI of over 25. As for smoking history, the average decrease for current smokers (-0.41L) was significantly larger than for non-smokers(-0.37L) and ex-smokers (-0.39L). When examined by FEV1.0 in 1997, the average decrease was significantly greater the larger the baseline FEV1.0 (under 3.0:-0.33L, between 3.0 and 3.5:-0.39L, over 3.5:-0.46).
Conclusions: As a smoking habit enhances the decline in FEV1.0, stopping smoking is necessary to prevent the appearance of obstructive pulmonary function.
