Dysanapsis ratio as a predictor for expiratory flow limitation

Joshua R. Smith, Sara K. Rosenkranz, Craig A. Harms

Research output: Contribution to journalArticlepeer-review


To determine the efficacy of the dysanapsis ratio (DR) in predicting expiratory flow limitation during exercise, 146 subjects (73 men, 73 women) performed standard pulmonary function and maximal incremental exercise tests. Tidal flow-volume loops were recorded at maximal exercise with maximal flow-volume loops measured pre- and post-exercise. Men had larger (p<. 0.05) lung volumes, flow rates, and VO2max compared to women, but DR was similar (0.21 ± 0.05 vs. 0.20 ± 0.06, respectively, p > 0.05). VO2max was not different (p > 0.05) between the EFL subjects compared to the non-EFL subjects for both men and women. Men with EFL compared to non-EFL men had smaller FVC (5.16 ± 0.89L vs. 5.67 ± 0.86L, p<. 0.05) and DR (0.19 ± 0.05 vs. 0.23 ± 0.04, p<. 0.05). Similarly, women with EFL compared to non-EFL had significantly smaller DR (0.18 ± 0.05 vs. 0.24 ± 0.05), but similar FVC (3.88 ± 0.52 vs. 4.12 ± 0.64, p > 0.05). A DR threshold was not determined; however, a DR continuum exists with increasing DR leading to decreased prevalence of EFL. In conclusion, DR is effective in determining the likelihood of EFL at maximal exercise.

Original languageEnglish (US)
Pages (from-to)25-31
Number of pages7
JournalRespiratory Physiology and Neurobiology
Issue number1
StatePublished - Jul 1 2014


  • Dysanapsis
  • Expiratory flow limitation
  • Pulmonary function

ASJC Scopus subject areas

  • General Neuroscience
  • Physiology
  • Pulmonary and Respiratory Medicine


Dive into the research topics of 'Dysanapsis ratio as a predictor for expiratory flow limitation'. Together they form a unique fingerprint.

Cite this