成人気管支喘息患者における治療効果と呼気中一酸化窒素濃度(FeNO:The Fraction of Exhaled Nitric Oxide)の変化  [in Japanese] THE EFFECT OF INHALED CORTICOSTEROID ON THE FRACTION OF EXHALED NITRIC OXIDE (FeNO) WITH OFF-LINE METHOD IN ADULT JAPANESE ASTHMATICS  [in Japanese]

【背景,目的】気管支喘息の治療評価の指標としてFeNOは有用とされている.簡便な方法としてオフライン法が挙げられるが,低流量オフライン法を用いたFeNO測定における治療経過での変化については報告がない.【対象,方法】ステロイド未治療の成人気管支喘息36例を対象とした.2006年喘息予防管理ガイドラインに基づく診断,治療を行いつつ,治療前,治療4週間後,治療12週間後に症状,FeNO,スパイロメトリーを行い,経過観察をした.【結果】36例全例で12週間後の症状は消失した.FeNO,FEV_1/FVCは4週後で有意な改善を認め,その効果は12週間後も継続した.(A)FEV_1/FVC前値<70%の群(n=11),(B)FEV_1/FVC前値≧70%(n=25)の二群で比較したところ,(A)群ではFeNO,FEV_1/FVCともに4,12週後で有意な改善を認めたのに対し,(B)群では4週目ではFEV_1/FVCのみ有意に改善を認めたのに対し,12週目ではFeNOのみ有意に改善を認めた.【結語】FeNOは気管支喘息の治療効果発現に伴い減少し,治療効果評価に有用である.

Background: The fraction of exhaled nitric oxide (FeNO) is a useful marker of asthma control. The FeNO measurement with our offline method using SIEVERS bag collection kit may be more affordable, but there have been no studies to show the effect of anti-asthmatic therapy on FeNO with our offline method. Methods: The study population comprised 36 steroid-naive asthmatics at our outpatient clinic. We treated them according to asthma prevention and management guideline 2006, Japan. We also measured eNO levels by our offline method and spirometory on baseline, 4 weeks, and 12 weeks of treatment. Results: All asthmatics were symptom-free on 12 weeks of treatment. The levels of FeNO FEV_1/FVC were significantly decreased on 4 weeks and 12 weeks of treatment, compared with that on first visit. We classified the subjects into two groups; (A) FEV_1/FVC<70% (n=11) or (B) FEV_1/FVC≧70% (n= 25) on baseline. In (A) group, the level of FeNO and FEV_1/FVC were significantly improved on 4 and 12 weeks of treatment. In (B) group, on 4 weeks of treatment, the level of FEV_1/FVC was significantly increased but the level of FeNO was not significantly changed. On 12 weeks of treatment, the levels of FeNO was significantly decreased, but the level of FEV_1/FVC was not significantly changed. Conclusion: The levels of FeNO were decreased by antiasthmatic therapy, so that offline monitoring of eNO will facilitate the management of bronchial asthma in patients treated with these drugs.