Table A12: Summary of Key Study Characteristics for the Three Studies on Health-related Quality of Life*.
| Author | Study Design |
Study Population | Intervention | Main Results† | Comments |
|---|---|---|---|---|---|
| Eaton et al (44) | Prospective follow-up: baseline to 2 and 6 months | 68 patients with COPD, NS LTOT need assessed by standard criteria: severe hypoxemia or mild-to-moderate hypoxemia with a COPD-related condition Clinically stable ≥ 2 months |
LTOT vs. no LTOT (43/25) |
Baseline: significant differences‡ in PaO2 (LTOT 51.8 vs. no LTOT 66 mm Hg), PaCO2 (LTOT 48.8 vs. no LTOT 42.8 mm Hg), and CRQ (fatigue, emotional function, mastery, total); FEV1 % predicted (LTOT: 31.7; no LTOT, 29.6) Mean O2 use 14.6 hours At 2 months CRQ total: LTOT 8.10 (3.02–13.17); no LTOT −0.28 (−5.98 to 5.42), significant increases for domains in LTOT At 6 months, CRQ total: LTOT 9.26 (2.37–16.15); no LTOT −2.56 (−8.31 to 3.19), significant increases for domains in LTOT |
>50% men Age ~70 years CRQ analyzed as total scores Other factors affecting HRQOL? Ambulatory O2 not provided |
| Crockett et al (45) | Prospective follow-up: baseline to 3, 6, and 12 months | 114 COPD patients LTOT need determined by standard criteria |
LTOT only (M 59/W 55) |
Baseline, PaO2 ~53.7 mm Hg, PaCO2 49.2 mm Hg, FEV1 0.5 L (men and women combined); mean O2 use ~19 hours Men: CRQ at all time points, emotional function and mastery: nonsignificant increase; fatigue: significant increase > 0.5 Women: CRQ mastery, significant increase > 0.5 at all time points; emotional function and fatigue: significant increase > 0.5 at 3 and 6 months |
~52% men Age ~70 years CRQ analysis mean score, 7-point scale Other factors affecting HRQOL? Ambulatory O2 provided MCID 0.5 units |
| Okubadejo et al (47) | Prospective follow-up: baseline to 2 weeks, and 3 and 6 months | 36 patients with COPD LTOT need assessed by standard criteria: severe hypoxemia or mild-to-moderate hypoxemia with a COPD-related condition Clinically stable ≥ 3 weeks |
LTOT vs. no LTOT (19/17) |
Baseline: LTOT, PaO2 ~52.5 mm Hg, PaCO2 50.3 mm Hg, FEV1 40% predicted; mean O2 use ~17 hours; no LTOT, PaO2 ~62.3 mm Hg, PaCO2 ~45 mm Hg, FEV1 43% predicted Significant differences between LTOT and no LTOT for SGRQ total at baseline (61.8 vs. 45.8, P = 0.008), no significant differences in improvement from baseline at 2 weeks and 3 and 6 months |
% by sex unknown Age ~71 years Other factors affecting HRQOL Ambulatory O2 not provided MCID 4 units |
*
Abbreviations: CRQ, Chronic Respiratory Questionnaire; COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 second; HRQOL, health-related quality of life; LTOT, long-term oxygen therapy; M, men; MCID, minimal clinically important difference; mm Hg, millimetres of mercury; NS, nonsmokers; O2, oxygen; PaCO2, arterial pressure of carbon dioxide; PaO2, arterial pressure of oxygen; SGRQ, St. George’s Respiratory Questionnaire; W, women.
†
Data are reported as means and 95% confidence intervals, or mean alone.
‡
Significant at < 0.05.