| dc.description.abstract | Turkish national guidelines recommend peak expiratory flow (PEF) measurements for assessing the reversibility of airflow obstruction in the primary care setting because it is cost-effective and practical. In this study, the usefulness and reliability of PEF as an alternative parameter to forced expiratory volume in 1 second (FEV1) as a reversibility test was investigated. Eighty-three subjects with asthma symptoms and airflow obstruction on spirometry met inclusion criteria. The mean age of the subjects was 42 ± 17.5 years; 52% were men. The FEV1% was between 53% and 80% in the study population. PEF was assessed using a manual peak flow meter, while FEV1 was obtained from the spirographic curve. A positive bronchodilator response was defined as an increase in FEV1 of >12% predicted after inhaling 400 ?g of salbutamol. This response was compared with an increase in PEF% from baseline with cutoff values of 15% and 20%. FEV1 >12%, PEF >15%, and PEF >20% bronchodilator response was observed in 59%, 61%, and 49% of patients, respectively. There was a weak correlation between postbronchodilator FEV1 and PEF increase (r = 0.275, P =.012). An increase in PEF >15% showed a sensitivity of 74%, specificity of 58%, positive predictive value (PPV) of 74%, and negative predictive value (NPV) of 59% compared with an FEV1 response of >12%. Similarly, an increase of PEF >20% had a sensitivity of 54%, specificity of 57%, PPV of 65%, and NPV of 45%. The clinical value of PEF measurements in the diagnosis of reversible obstructive airway disease was less reliable than FEV1. Therefore, it should be reevaluated for widespread usage. © 2010 The Author(s). | en_US |
