Comparison of lung function indices, respiratory muscle strength, and 6MWD in SARS survivors who had required ICU care (n = 31) versus those treated on the wards (n = 79)
3 months | 6 months | Mean (SE) difference 6–3 months | |
---|---|---|---|
FVC, forced vital capacity; FEV1, forced expiratory volume in 1 second; VC, vital capacity; TLC, total lung capacity; RV, residual volume; Tlco, carbon monoxide transfer factor adjusted for haemoglobin; Kco, transfer coefficient (transfer factor per alveolar volume); Pimax, Pemax, maximum static inspiratory and expiratory pressures; 6MWD, 6 minute walk distance. | |||
Values are shown as mean (SD) ICU v non-ICU with 95% CI of difference and p values. | |||
*Statistically significant. | |||
FVC (% of predicted) | |||
Mean (SD) | 94.3 (14.0) v 107.6 (12.1) | 98.6 (15.8) v 106.1 (13.5) | 4.3 (1.7) v −1.6 (1.0) |
95% CI | 7.9 to 18.7 | 1.5 to 13.5 | −9.6 to −2.1 |
p value | p<0.01* | p = 0.02* | p<0.01* |
FEV1 (% of predicted) | |||
Mean (SD) | 102.0 (13.1) v 111.1 (14.7) | 103.8 (12.7) v 108.2 (15.4) | 1.8 (1.2) v −2.9 (1.3) |
95% CI | 3.0 to 15.1 | −1.8 to 10.6 | −9.0 to −0.4 |
p value | p<0.01* | p = 0.17 | p = 0.03* |
VC (% of predicted) | |||
Mean (SD) | 94.7 (15.1) v 107.9 (12.5) | 98.4 (16.4) v 105.0 (17.9) | 3.7 (1.4) v −2.8 (1.4) |
95% CI | 7.4 to 18.9 | −0.9 to 14.1 | −11.3 to −1.8 |
p value | p<0.01* | p = 0.08 | p = 0.01* |
TLC (% of predicted) | |||
Mean (SD) | 94.6 (16.1) v 110.3 (16.4) | 98.2 (19.3) v 110.1 (14.1) | 3.6 (3.9) v −0.2 (1.9) |
95% CI | 8.7 to 22.7 | 4.0 to 19.7 | −11.6 to 4.0 |
p value | p<0.01* | p<0.01* | p = 0.33 |
RV (% of predicted) | |||
Mean (SD) | 96.7 (39.4) v 115.7 (49.7) | 99.9 (51.6) v 118.6 (38.5) | 3.2 (12.3) v 2.9 (6.2) |
95% CI | −1.2 to 39.2 | −2.4 to 39.7 | −25.0 to 24.3 |
p value | p = 0.06 | p = 0.08 | p = 0.98 |
Tlco (% of predicted) | |||
Mean (SD) | 84.3 (17.5) v 101.4 (13.4) | 87.7 (21.0) v 98.3 (16.6) | 3.4 (2.2) v −2.9 (1.6) |
95% CI | 10.9 to 23.4 | 3.0 to 18.2 | −11.9 to −0.6 |
p value | p<0.01* | P = 0.01* | p = 0.03* |
Kco (% of predicted) | 4.5(1.7) vs 2.6(1.3) | ||
Mean (SD) | 104.9 (13.5) v 107.4 (13.7) | 109.4 (15.3) v 110.1 (13.6) | |
95% CI | −3.4 to 8.2 | −5.3 to 6.7 | −6.5 to 2.7 |
p value | p = 0.41 | P = 0.83 | p = 0.42 |
Pimax (% of predicted) | |||
Mean (SD) | 104.2 (29.1) v 108.5 (29.8) | 105.6 (30.6) v 105.8 (25.8) | 0.6 (5.6) v −2.6 (2.7) |
95% CI | −8.5 to 17.0 | −11.4 to 11.8 | −14.0 to 7.6 |
p value | p = 0.51 | P = 0.97 | p = 0.56 |
Pemax (% of predicted) | |||
Mean (SD) | 75.7 (14.9) v 73.2 (18.9) | 74.5 (19.1) v 71.5 (21.4) | −1.8 (2.8) v −1.5 (2.1) |
95% CI | −10.2 to 5.2 | −11.9 to 5.8 | −7.1 to 7.6 |
p value | p = 0.52 | P = 0.49 | p = 0.94 |
6MWD (m) | |||
Mean (SD) | 458.2 (86.8) v 466.4 (80.7) | 519.7 (101.4) v 491.5 (92.9) | 64.5 (14.5) v 25.1 (9.7) |
95% CI | −27.1 to 43.6 | −11.4 to 11.8 | −74.9 to −4.0 |
p value | p = 0.64 | P = 0.97 | p = 0.03* |