A Cochrane review included 29 studies; 23 studies (n=3 189) compared self-management with usual care, and 6 studies (n=499) compared different components of self management head-to-head. In the 23 studies with a usual care control group, follow-up time ranged from 2 to 24 months. The content of the interventions was diverse. Self management improved quality of life as measured by the St George's Respiratory Questionnaire (SGRQ) total score (table ) and decreased respiratory-related hospital admissions, but did not have any statistically significant effect on all-cause hospital admissions or mortality (table ). Over one year of follow-up, 8 (95% CI 5 to 14) participants with a high baseline risk of respiratory-related hospital admission needed to be treated to prevent one participant with at least one hospital admission, and 20 (95% CI 15 to 35) participants with a low baseline risk of hospitalisation needed to be treated to prevent one participant with at least one respiratory-related hospital admission.
| Outcome | Control group | Self management group | Participants (studies) |
|---|---|---|---|
| HRQoL = Health related quality of life; SGRQ = St George's Respiratory Questionnaire; (m)MRC = (modified) Medical Research Council Scale; 6MWD = six-minute walking distance | |||
| HRQoL: SGRQ total score (Scale 0-100; lower score indicates better HRQoL ) | Range of mean SGRQ total scores in the control group varied from 34.7 to 65.3 points | Mean SGRQ total score in the intervention group was 3.51 lower (5.37 to 1.65 lower) | 1 413 (10 studies) |
| Dyspnoea: (m)MRC score | Range of mean (m)MRC scores in the control group varied from 2.4 to 3.6 points | Mean (m)MRC total score in the intervention group was 0.83 lower (1.36 to 0.3 lower) | 119 (3 studies) |
| Exercise capacity: 6MWD | Range of mean 6MWD in the control group varied from 68.6 to 440.9 m | Mean 6MWD in the intervention group was 33.69 higher (9.12 lower to 76.50 higher) | 570 (6 studies) |
| Outcome | Relative effect (95% CI) | Assumed risk - control | Corresponding risk - self management | Participants (studies) |
|---|---|---|---|---|
| Respiratory-related hospital admissions | OR 0.57 (0.43 to 0.75 ) | 293 per 1000 | 190 per 1000 (151 to 237) | 1 749 (9 studies) |
| All-cause hospital admissions | OR 0.77 (0.45 to 1.30 ) | 413 per 1000 | 310 per 1000 (241 to 478) | 1 365 (6 studies) |
| Courses of oral steroids | OR 4.42 (0.39 to 50.10 ) | 541 per 1000 | 892 per 1000 (315 to 983) | 901 (3 studies) |
| Mortality | OR 0.79 (0.58 to 1.07 ) | 97 per 1000 | 79 per 1000 (59 to 103) | 2 134 (8 studies) |
No effects of self management on lung function were found, but dyspnoea as measured by the (modified) Medical Research Council Scale ((m)MRC) was significantly reduced in participants assigned to self management. The difference in exercise capacity as measured by the six-minute walking test was not statistically significant (table ). Subgroup analyses depending on the use of an exercise programme as part of the intervention revealed no statistically significant differences between studies with and without exercise programmes in the primary outcomes of HRQoL and respiratory-related hospital admissions. Head-to-head trials were not pooled because of heterogeneity among interventions and controls.
Comment: The quality of evidence is downgraded by inconsistency.