Masaharu Asai

Effect of a chronic obstructive pulmonary disease (COPD) intervention on COPD awareness in a regional city in Japan.

OBJECTIVE The purpose of this study was to examine the effect of an intervention for chronic obstructive pulmonary disease (COPD) on COPD awareness in a regional city in Japan. METHODS Self-administered questionnaires were completed by the residents of the city of Matsuura, Japan. Residents (≥50 years) of the mainland in Matsuura were included in a COPD intervention project (mainland group), while residents of the islands district received no intervention due to geographical issues (island group). The rates of COPD awareness and accuracy of responses to the questions about COPD were compared between the two groups. MATERIALS The study included 5,891 residents 40 to 74 years of age of Matsuura in 2013. The mainland group comprised 4,419 subjects, and the island group 1,472 included subjects. RESULTS The overall response rate to the questionnaire was 24.6%, with similar response rates between the two groups. The rate of COPD awareness in the mainland group was 24.5%, which was significantly higher than that observed in the island group (11.8%) (p<0.01). The rate of awareness tended to decrease in association with increasing age. Among 276 responders who stated they were aware of COPD, the accuracy rate for responses to the questions about COPD was not significantly different between the groups. CONCLUSION In the present study, there was a difference in COPD awareness between the two groups, suggesting that COPD interventions may increase awareness of the disease. However, the level of knowledge regarding COPD remained low and modifications to the intervention are required to improve awareness of the condition, especially among elderly subjects.

Value of systematic intervention for chronic obstructive pulmonary disease in a regional Japanese city based on case detection rate and medical cost

Objective We established a COPD taskforce for early detection, diagnosis, treatment, and intervention. We implemented a pilot intervention with a prospective and longitudinal design in a regional city. This study evaluates the usefulness of the COPD taskforce and intervention based on COPD case detection rate and per capita medical costs. Method We distributed a questionnaire to all 8,878 inhabitants aged 50–89 years, resident in Matsuura, Nagasaki Prefecture in 2006. Potentially COPD-positive persons received a pulmonary function test and diagnosis. We implemented ongoing detection, examination, education, and treatment interventions, performed follow-up examinations or respiratory lessons yearly, and supported the health maintenance of each patient. We compared COPD medical costs in Matsuura and in the rest of Nagasaki Prefecture using data from 2004 to 2013 recorded by the association of Nagasaki National Health Insurance Organization, assessing 10-year means and annual change. Results As of 2014, 256 people have received a definitive diagnosis of COPD; representing 31% of the estimated total number of COPD patients. Of the cases detected, 87.5% were mild or moderate in severity. COPD medical costs per patient in Matsuura were significantly lower than the rest of Nagasaki Prefecture, as was rate of increase in cost over time. Conclusion The COPD program in Matsuura enabled early detection and treatment of COPD patients and helped to lower the associated burden of medical costs. The success of this program suggests that a similar program could reduce the economic and human costs of COPD morbidity throughout Japan.

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.

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.