The association between risk of airflow limitation and serum uric acid measured at medical health check-ups.

The prevalence of COPD and asthma is increasing all over the world; however, their morbidities are thought to be greatly underestimated because of unawareness of patients' conditions and respiratory symptoms. Spirometry is useful for the early detection of COPD and asthma with airflow limitation (AL), although it is not yet widely used for screening in epidemiological and primary care settings. A simple predictive marker used in combination with spirometry for AL is expected to be established.