Trends in the prevalence of COPD in elderly individuals in an air-polluted city in Japan: a cross-sectional study.

Purpose: The aim of this study was to examine the effects of exposure to air pollution and cigarette smoke on respiratory function, respiratory symptoms, and the prevalence of COPD in individuals aged ≥50 years. Patients and methods: We used spirometry and medical questionnaires to screen 433 individuals from Omuta City, Japan, an area with high levels of air pollution. Results: Non smokers had a high estimated COPD prevalence rate of 16%. Among smokers, the estimated prevalence of COPD was 29% in seniors (50- to 74-years group) and 37% in the elderly (>75 years group). We also found a correlation between levels of suspended particulate matter and COPD. Conclusion: Both smoking and chronic exposure to air pollution (>5 years) decreased respiratory function, exacerbated respiratory symptoms, and increased the prevalence of COPD. We strongly recommend periodic screening for the elderly patients to facilitate early detection of respiratory disease.

Effectiveness of diagnostic screening tests in mass screening for COPD using a cooperative regional system in a region with heavy air pollution: a cross-sectional study.

OBJECTIVES: This study aimed to evaluate the effectiveness of a cooperative healthcare model for early detection and diagnosis of chronic obstructive pulmonary disease (COPD). METHODS: This was a cross-sectional observational study. We performed diagnosis of COPD at 4 public health centres in Omuta, Japan from March 2015 to March 2016, by adding screening for COPD at the time of routine medical evaluations. All patients aged over 40 years were eligible to participate. Among 397 eligible patients, 293 agreed to participate in the study. RESULTS: The estimated prevalence of COPD in Omuta was 10% among patients aged over 40 years and was 17% among smokers. Among those who were screened, over half of them had questionnaire scores over the cut-off of 17 points and decreased FEV1/FVC%, indicating COPD (p>0.05). 30 patients with suspected COPD were referred for further investigation at a local central hospital, but only 6 underwent further medical examinations. CONCLUSIONS: The combination of a COPD questionnaire and medical examination is effective as a COPD screening tool. Future research should investigate behavioural interventions for smoking cessation that can be offered in a cooperative model, as well as for improving participation in COPD screening and for encouraging early presentation for treatment in those suspected of having COPD.

Factors associated with the annual change in forced expiratory volume in 1 second of officially acknowledged victims of pollution-related illness in improved environments: a longitudinal study.

[Purpose] We examined factors affecting annual change in pulmonary function in residents previously exposed to air pollution in an area where pollution has been reduced and a long time period has elapsed. [Subjects and Methods] Data of 730 officially acknowledged victims of pollution-related illness from an annual survey during 2000 to 2009 were analyzed. The primary outcome was forced expiratory volume in 1 second (FEV1), along with factors such as age, body composition, smoking habits, respiratory symptoms, and classification of medical management (an index of the need for treatment). Multiple regression analyses were used to identify factors associated with the annual change in FEV1. [Results] Three significant factors were identified: smoking habit, classification of medical management, and gender. Smoking habits and classification of medical management had stronger effects on the annual change in FEV1 than gender. [Conclusion] With an improved environment, continuation of smoking accelerates the decline in FEV1.

Smoking aggravates the impaired pulmonary function of officially acknowledged female victims of air pollution of 40 years ago.

Air pollution due to industrial waste and tobacco smoke is detrimental to pulmonary function. However, the combined effects of air pollution and smoking on pulmonary function have not been investigated. We examined the combined effect of air pollution of 40 years ago and concurrent smoking on the pulmonary function of officially acknowledged female victims in Japan, because females are more susceptible to the adverse effects of both irritants than males. The subjects comprised 655 female victims living in one of two areas with air pollution of 40 years ago and 572 females living in an area without air pollution. All victims have been prescribed standard respiratory medications. Pulmonary function was measured in 2000 for air-pollution groups (130 smokers and 525 non-smokers; mean age, 68.4 years) and during the period of 2004 to 2013 for non-air-pollution groups (113 smokers and 459 non-smokers; mean age, 69.0 years). The smokers included both current smokers and ex-smokers. The victims with a history of smoking had significantly lower forced expiratory volume in 1 second (FEV1 % predicted) (mean, 74%) and significantly lower FEV1/forced vital capacity (FVC) (mean, 70%) than the other groups (P<0.001). Thus, smoking aggravates the pulmonary function in officially acknowledged female victims, despite the improved air pollution and the continuous medical care provided by the government. In conclusion, exposure to air pollution of 40 years ago and cigarette smoking are associated with reduced pulmonary function. These results highlight the importance of measures aimed at smoking cessation and limiting air pollution.

Tobacco use among designated air pollution victims and its association with lung function and respiratory symptoms: a retrospective cross-sectional study.

OBJECTIVES: We sought to elucidate the long-term association of tobacco use and respiratory health in designated pollution victims with and without obstructive pulmonary defects. DESIGN: A retrospective cross-sectional study. SETTING: The register of pollution victims in Kurashiki, Japan. PARTICIPANTS: 730 individuals over 65 years of age previously diagnosed with pollution-related respiratory disease. Patients were classified into four groups according to their smoking status and whether they had obstructive pulmonary disease. We then compared the prevalence of respiratory symptoms and lung function over time between groups. PRIMARY OUTCOME MEASURES: Spirometry was performed and a respiratory health questionnaire completed in the same season each year for up to 30 years. RESULTS: Rates of smoking and respiratory disease were high in our sample. Although respiratory function in non-smoking patients did not completely recover, the annual rate of change in lung function was within the normal range (p<0.01). However, smokers had worse lung function and were more likely to report more severe pulmonary symptoms (p<0.01). CONCLUSIONS: Patients' respiratory function did not fully recover despite improved air quality. Our results suggest that, in the context of exposure to air pollution, tobacco use causes additional loss of lung function and exacerbates respiratory symptoms.

Pulmonary rehabilitation improves exercise capacity and dyspnea in air pollution-related respiratory disease.

Air pollution in Japan caused respiratory disease, such as chronic bronchitis and asthma, in many individuals in the 1960s. Although air pollution has decreased, many victims of air pollution-related respiratory disease are limited in their activities of daily living because of respiratory symptoms. The purpose of this study was to evaluate the efficacy of pulmonary rehabilitation in victims of air pollution-related chronic bronchitis or asthma. Subjects were enrolled in a 12-week (2-week inpatient followed by 10-week outpatient) pulmonary rehabilitation program. The program comprised conditioning, strength training, endurance training, and patient education. We assessed the Modified Medical Research Council (MMRC) dyspnea grade, pulmonary function, peripheral muscle force, incremental shuttle walk distance (ISWD), and physical activity at baseline and immediately after the program. Twenty-nine subjects (mean age 74.2 ± 10.1 years, 11 males) completed the program, including 11 subjects with COPD and 18 subjects with asthma. Following rehabilitation, the participants (n = 29) showed significant improvements in MMRC dyspnea grade, vital capacity % predicted, quadriceps force and ISWD (all P < 0.05). Sub-group analyses revealed that all these variables were significantly improved in subjects with asthma. In contrast, subjects with COPD showed significant improvements only in quadriceps force and ISWD (both P < 0.05). Thus, pulmonary rehabilitation is an effective method of improving exercise capacity and dyspnea in officially acknowledged victims of air pollution-related asthma. In conclusion, we recommend that patients with chronic bronchitis or asthma, resulting from exposure to air pollution, are referred for pulmonary rehabilitation.

Longitudinal study of respiratory function and symptoms in a non-smoking group of long-term officially-acknowledged victims of pollution-related illness.

BACKGROUND: Air pollution is known to be a leading cause of respiratory symptoms. Many cross-sectional studies reported that air pollution caused respiratory disease in Japanese individuals in the 1960s. Japan has laws regulating air pollution levels and providing compensation for victims of pollution-related respiratory disease. However, long-term changes in respiratory function and symptoms in individuals who were exposed to air pollution in the 1960s have not been well studied. This study aimed to investigate longitudinal respiratory function and symptoms in older, non-smoking, long-term officially-acknowledged victims of pollution-related illness. METHODS: The study included 563 officially-acknowledged victims of pollution-related illness living in Kurashiki, Okayama who were aged ≥ 65 years in 2009. Data were retrospectively collected from yearly respiratory symptom questionnaires and spirometry examinations conducted from 2000 to 2009. RESULTS: Respiratory function declined significantly from 2000 to 2009 (p < 0.01), but the mean annual changes were relatively small. The change in mean vital capacity was -40.5 ml/year in males and -32.7 ml/year in females, and the change in mean forced expiratory volume in 1 second was -27.6 ml/year in males and -23.9 ml/year in females. Dyspnea was the only symptom that worsened significantly from 2000 to 2009 in both sexes (males: p < 0.05, females: p < 0.01). CONCLUSIONS: Our results suggest that the high concentrations of air pollutants around 1970 resulted in a decrease in respiratory function and an increase in respiratory symptoms in the study population. From 2000 to 2009, the mean annual changes in respiratory function were within the normal range, even though the severity of dyspnea worsened. The changes in respiratory function and symptoms over the study period were probably due to aging. The laws governing air pollution levels and providing compensation for officially-acknowledged victims of pollution-related illness in Japan may be effective for respiratory disease cause by pollution.

Air pollution irreversibly impairs lung function: a twenty-year follow-up of officially acknowledged victims in Japan.

Lung function is one of the strongest determinants of cardiopulmonary health and longevity. Long-term exposure to air pollution has been associated with decreased lung function. We undertook a retrospective study to compare the long-term consequences of air pollution in two areas of Japan: Mizushima, Okayama Prefecture and Kitakyushu, Fukuoka Prefecture. Industrialization began in Mizushima in the 1940s, whereas it began in Kitakyushu in the early 1900s. In Kitakyushu, levels of nitrogen dioxide have been higher compared to the Mizushima area. The subjects comprised 623 officially acknowledged victims of pollution-related illness (489 from Mizushima and 134 from Kitakyushu). All subjects were lifetime non-smokers and aged 65 years or older at the time of their last medical examination in 2009. Demographic data including diagnosed lung diseases and lung function at the time of certification assessment performed between 1973 and 1988 were obtained. The subjects from Kitakyushu were significantly younger (47.1 vs. 51.0 years, p < 0.001) and a higher percentage had asthma (91.2 vs. 36.8%, p < 0.001) compared to those from Mizushima. Furthermore, all measures of lung function were significantly lower in Kitakyushu group at the time of the certification assessment (p < 0.001) and at the follow-up (p < 0.001). However, no significant differences were observed in the annual mean decline in lung function between the two groups, despite the overall decrease in air pollution. In conclusion, the normal lung function is not restored even after improvement of air pollution. It is essential for every city to prevent air pollution.