Effect ofAgeUponAirway Obstruction andReversibility inAdultPatients WithAsthma

lator test(p < 0.001), themaximumresponse achievable withtreatment(steroid or bronchodi¬ lator) (AFEVX expressed as thepercent ofpredicted) was notstatistically different between groups (12.0 ± 17.5 vs 16.0± 23.9). Themean FEVi attainable after treatment(AFEV^PT) was significantly lower intheolder group(p = 0.0006). Within groups, thebaseline FEVX% didnot correlate withage;itwas inversely correlated withtheduration ofthedisease (p < 0.03and p < 0.01, respectively). InbothgroupsAFEV! was inversely related withthebaseline FEV1? whereas FEVX%PT was correlated withtheduration ofthedisease, with aslope nearly doubled ingroup B(p < 0.001). Conclusions: Boththeprocess ofaging andtheprolonged exposure todisease effects are important factors indetermining thefunctional characteristics ofchronic asthma: Inparticular, aging isassociated notonly with areduced acuteresponsiveness tobronchodilators, butalso with a reduced slope oftheduration-FEV1%PT relationship thatsuggests aslowing oftherateofloss ofreversibility ofuncertain biological meaning. (CHEST 1998; 114:1336-1342)