Abstract
A study of the prevalence of respiratory symptoms and pulmonary functions in inhabitants living at the clean air area was done from November 1978 to September 1979. Sub jects of the study were 826 inhabitants from 30 to 49 years of age at clean air areas, Yonezawa and Higashine in Yamagata Prefecture.
The following results were obtained.
1.%VC was 103.4% in males and 107.2% in females. FEV 1.0% was 82.0% in males and 84.9% in females. These values were higher than those of another rural area. Pulmonary obstructive and restrictive incompetency were found to be 5% at the most, and mixed incompetency was zero.
2. V750/Ht was 4.4l/sec in males and 3.7l/sec in females.V725/Ht was 1.6l/sec in males and 1.4l/sec in females. And, V.50/V25 was 2.8 in both males and females. Those values were much the same as those of another roural area. An abnormal rate of V50/V25 was 3.8% found in both males and females. This rate was less than in another rural area.
3. Persisent cough (grade 1) was found in 1.8% of the males and 0.2% of the females and persisent phlegm (grade 1) in 3.3% of the males, 1.3% of the females. These rates were lower than those of another rural area (Sakai Gun) in Fukui Prefecture. And “Persisent cough, phlegm” and “Chronic bronchial symptom” were found rarer than in another area.
4. “stridor” was found in 1.8% of the males and 1.1% of the females. These rates were extremely low level, similar to the lowest cough and phlegm level area in Japan.
