Weight-based reference equations for the 6-min walk test can be misleading in obese patients. Issue 2 (11th May 2020) - Haynes, Jeffrey M.
A 79-year-old female presented to a hospital-based laboratory for pulmonary function testing and a 6-min walk test (6MWT). The patient's chief complaint was dyspnoea on exertion. The patient was a life-long nonsmoker with a history of interstitial lung disease and morbid obesity (body mass index (BMI) 44.9 kg·m −2 ). The patient's baseline spirometry data were within normal limits but the diffusing capacity was moderately reduced (50% of predicted; z-score −4.05) [1, 2]. Weight-based reference equations for the 6-min walk test can produce normal results despite poor performance. Using ideal body weight- or non-weight-based reference equations for the 6-min walk test may produce more clinically meaningful results. https://bit.ly/2wE9Sdn