年令から見た気管支喘息症例の臨床的特徴

高齢気管支喘息症例の病態を解明するために30才以降の気管支喘息症例について年齢層別に臨床的特徴を検討した｡1)60才以上の高齢気管支喘息症例は全体の41.1%を占めており,年齢層別では50-59才,60-69才の症例が多く認められた｡2)ほとんどの症例が成人発症喘息であり,高齢気管支喘息では92.3%が中高年発症型気管支喘息であった｡3)加齢に伴って細気管支閉塞型気管支喘息の増加か認められた｡4)血清IgE値は50-59才で再増加し,histamine release,LTC(4)産生は40149才で高値であった｡5)40-69才の年齢層でステロイド依存性難治性喘息が多く認められた｡以上高齢気管支喘息症例は中高年発症型喘息の病態の特徴を有しており,中高年発症型気管支喘息の病態の解明が必要と考えられた｡

To examine clinical characteristics of asthma in elderly (over 60 years), age at onset, clinical asthma types, glucocorticoid therapy, serum IgE levels and release of chemical mediators (histamine and leukotriene C(4)) were examined in 145 asthmatics over 30 years and divided into five age groups ; 30-39, 40-49, 50-59, 60-69, 70-79 years. 1. The freqeuncy of asthmatics was 13.7% in age group between 30 and 39, 14.4% between 40 and 49, 30.8% between 50 and 59, 28.8% between 60 and 69, 12.3% between 70 and 79 years, respectively. The frequency of elder asthmatics (over age 60) was 41.1%. 2. The frequency of adult onset asthma (over 20 years) was 90.3% of all subjects, and the frequency of late onset asthma (over 40 years) was 92.3% of elderly subjects over age 60. 3. Numbers of asthmatics with bronchiolar obstruction type show a tendency to increase with aging. 4. Serum IgE level was increased in subjects aged 50-59 years. Histamine release (%) and release of leukotriene C(4) from peripheral leukocytes were higher in age group between 40 and 49 compared to those in the other age groups. 5. Number of patients with steroid-dependent intractable asthma was increased in age group between 40 and 69. These results suggest that elderly asthmatics show the characteristics of late onset asthma, and further examinations of late onset asthma is important to clarify the pathogenesis of asthma in elderly.