Table 2.

Outcome Measures – Estimated Changes over 60 Weeks

Endpoint	NAC (N=133)	Placebo (N=131)	Treatment Difference (95% Confidence Interval)	P-value
Forced vital capacity (liters)	−0.18	−0.19	0.01 (−0.06, 0.09)	0.77
Pre-alert	−0.17	−0.22	0.06 (−0.04, 0.15)	0.27
Post-alert	−0.19	−0.13	−0.06 (−0.18, 0.06)	0.32
Carbon monoxide diffusion corrected for hemoglobin (mL/min/mmHg)	−1.3	−1.4	0.2 (−0.4, 0.8)	0.56
Pre-alert	−1.1	−1.9	0.8 (0.1, 1.5)	0.028
Post-alert	−1.4	−0.8	−0.7 (−1.6, 0.3)	0.18
6-minute walk test distance (meters)	−23.4	−47.5	24.2 (−2.6, 50.9)	0.076
Pre-alert	−27.2	−67.7	40.5 (6.1, 74.8)	0.021
Post-alert	−14.1	−15.8	1.7 (−38.7, 42.1)	0.93
UCSD shortness of breath questionnaire	6.0	5.8	0.2 (−4.1, 4.4)	0.94
Pre-alert	5.6	7.6	−2.1 (−8.3, 4.2)	0.52
Post-alert	7.4	2.8	4.6 (−0.7, 9.8)	0.086
SGRQ – total score	4.3	5.5	−1.2 (−4.9, 2.4)	0.51
Pre-alert	4.5	7.7	−3.3 (−8.3, 1.7)	0.20
Post-alert	4.3	2.7	1.6 (−3.7, 6.9)	0.55
SF-36: aggregate mental score	0.0	−2.6	2.6 (0.3, 5.0)	0.025
Pre-alert	0.8	−3.5	4.3 (1.3, 7.3)	0.005
Post-alert	−1.3	−1.2	−0.1 (−3.8, 3.6)	0.97
ICECAP summary score	0.01	−0.02	0.03 (0.01, 0.05)	0.013
Pre-alert	−0.00	−0.05	0.04 (0.01, 0.08)	0.008
Post-alert	0.02	0.00	0.01 (−0.02, 0.05)	0.40
EuroQoL visual analog score	0.9	−3.3	4.2 (−0.3, 8.8)	0.069
Pre-alert	−1.7	−7.6	5.9 (−0.1, 11.9)	0.054
Post-alert	4.5	1.6	2.8 (−3.8, 9.4)	0.40

For each endpoint the first row is the overall result, the second row is the pre-alert cohort, and the third row is the post-alert cohort.

Abbreviations: SGRQ denotes St George’s respiratory questionnaire; EuroQoL denotes EuroQoL Group 5-Dimension; SF-36 denotes the Medical Outcomes Study 36-Item Short-Form Health Survey; and ICECAP denotes ICEpop CAPability measure for Older people.