1 Division of Internal Medicine, Japan Agricultural Cooperatives Kochi Hospital, Nankoku, Kochi, Japan.
2 Department of Respiratory Medicine, Japanese Red Cross Kochi Hospital, Kochi-City, Kochi, Japan.
3 Department of Respiratory Medicine, Japanese Red Cross Kochi Hospital, Kochi-City, Kochi, Japan; Department of Clinical Investigation, National Hospital Organization Kochi Hospital, Kochi-City, Kochi, Japan.
4 Division of Internal Medicine, Japan Agricultural Cooperatives Kochi Hospital, Nankoku, Kochi, Japan; Department of Community Medicine for Respirology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan. Electronic address: t-shinohara@kouseiren.ja-kochi.or.jp.