喘息患者におけるピークフローの自己最良値の求め方の検討 : ピークフローの日常時の最高値と高用量の吸入ステロイド投与にSalbutamol MDI反復吸入を用いて求めた最高値との比較  [in Japanese] STUDY OF PERSONAL BEST VALUE OF PEAK EXPIRATORY FLOW IN PATIENTS WITH ASTHMA : Comparison of the Highest Value of Daily PEF under Good Control and the Highest Value of Daily PEF Obtained after Using Repeated Inhaledβ2-Agonist during High-Dose Inhaled Steroid Treatment  [in Japanese]

【背景】喘息のガイドラインにおいて,個々の患者のピークフロー(PEF)最良値を求めることは治療管理上重要である.従来PEFの最良値は,安定した日常時の最高値を目安とされてきた.【目的】本研究では,症状が安定した状態での日常時の最高値が最良値として適しているかを検討した.【方法】PEFが基準値の80%未満の中等症以下の喘息患者30名を対象に,日常時の最高値とsalbutamol MDIの20分毎の3回反復吸入後の最高値を比較した.その後全例BDP-CFC1600μg/日に4〜8週間増量し,その間の日常時の最高値の変動とsalbutamol後の最高値の変動とを比べ,また両者も比較検討した.【結果】いずれも高用量の吸入ステロイド投与により有意に上昇し,その上でsalbutamol使用後の値が一番高かった.【考察】日常安定時の最高値は気道炎症の程度に伴い変動するため,最良値としては適切でなく,最良値を求めるのに,軽・中等症喘息(Step2,3)においては4週間以上の高用量の吸入ステロイド投与とsalbutamol吸入の併用は有用であると考えられた.

Background: In the guideline for asthma management, it is important to find the personal best value of peak expiratory flow (best PEF). Recently, we have substituted the highest value of PEF in daily life under good control (daily highest PEF) for the best PEF. Aim: In the present study, we considered whether the daily highest PEF could be used as the best PEF or not. Method: Subjects were 30 asthmatics who were well controlled but whose baseline PEF values were less than 80 percent of predicted values. We compared the daily highest PEF and the highest of PEF obtained after repeated inhaled β2-agonist (salbutamol MDI every 20 minutes three times). All subjects then received 1600μg/day of beclomethasone dipropionate (BDP) for 4 to 8 weeks. We studied the effect of high-dose inhaled steroid treatment on each PEF value and compared the daily highest PEF and the highest PEF obtained after using repeated salbutamol MDI during high dose inhaled steroid therapy on the examination day again. Result: The baseline PEF, daily highest PEF and the highest PEF obtained after salbutamol MDI were significantly less than the each values obtained after high-dose BDP. The best PEF value of them was the value obtained after repeated salbutamol MDI during high dose BDP. Discussion: We suggest that the daily highest PEF under good control is not a substitute for best PEF because it changes according to the degree of improvement of airway inflammation. We recommend that a course of high dose inhaled steroid is effective in finding the best value of PEF for each individual with moderate asthma.