Table 2

Change in physiological measurements over the study period (n = 56)


Baseline (sd)
Follow up (sd)
Annual change (95% confidence interval) p value

FEV1 (L)
1.89 (0.71)
1.74 (0.68)
-37.7 ml (-52.0 to -23.4), p < 0.001
FEV1 (% predicted)
76.8 (25.1)
74.0 (27.3)
-0.8 (-1.5 to 0.0), p < 0.05
FVC (L)
3.38 (0.88)
3.26 (0.85)
-28.9 ml (-50.4 to -7.3), p < 0.01
FVC (% predicted)
109.0 (19.3)
111.0 (25.1)
0.36 (-0.5 to 1.2), Not significant
FEV1/FVC (%)
56.6 (0.17)
53.6 (0.17)
0.75 (0.40 to 1.1), p < 0.001
TLCO (mmol/min/kpa)
6.5 (2.4)
5.8 (2.4)
-0.15 (-0.21 to -0.09), p < 0.001
TLCO (% predicted)
81.8 (27.4)
76.2 (27.3)
-1.3 (-2.1 to -0.6), p < 0.001
KCO (mmol/min/kpa/L)
1.3 (0.4)
1.2 (0.4)
-0.02 (-0.03 to -0.01), p < 0.001
KCO (% predicted)
90.9 (31.6)
85.0 (31.4)
-1.4 (-2.1 to -0.7), p < 0.001

No change in static lung volume measurements was observed over the study period.

sd = standard deviation.

Parr et al. Respiratory Research 2006 7:136   doi:10.1186/1465-9921-7-136