Chronic obstructive pulmonary disease prognostic score: A new index

Predictors of mortality in chronic obstructive pulmonary disease: a systematic review and meta-analysis

Background

Better insight in patients’ prognosis can help physicians to timely initiate advance care planning (ACP) discussions with patients with chronic obstructive pulmonary disease (COPD). We aimed to identify predictors of mortality.

Methods

We systematically searched databases Embase, PubMed, MEDLINE, Web of Science, and Cochrane Central in April 2020. Papers reporting on predictors or prognostic models for mortality at 3 months and up to 24 months were assessed on risk-of-bias. We performed a meta-analysis with a fixed or random-effects model, and evaluated the discriminative ability of multivariable prognostic models.

Results

We included 42 studies (49–418,251 patients); 18 studies were included in the meta-analysis. Significant predictors of mortality within 3–24 months in the random-effects model were: previous hospitalization for acute exacerbation (hazard ratio [HR] 1.97; 95% confidence interval [CI] 1.32–2.95), hospital readmission within 30 days (HR 5.01; 95% CI 2.16–11.63), cardiovascular comorbidity (HR 1.89; 95% CI 1.25–2.87), age (HR 1.48; 95% CI 1.38–1.59), male sex (HR 1.68; 95% CI 1.38–1.59), and long-term oxygen therapy (HR 1.74; 95% CI 1.10–2.73). Nineteen previously developed multicomponent prognostic models, as examined in 11 studies, mostly had moderate discriminate ability.

Conclusion

Identified predictors of mortality may aid physicians in selecting COPD patients who may benefit from ACP. However, better discriminative ability of prognostic models or development of a new prognostic model is needed for further large-scale implementation.

Registration: PROSPERO (CRD42016038494), https://www.crd.york.ac.uk/prospero/.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01911-5.

Benefits of different intensities of pulmonary rehabilitation for patients with moderate-to-severe COPD according to the GOLD stage: a prospective, multicenter, single-blinded, randomized, controlled trial

Purpose

Pulmonary rehabilitation (PR) is essential to manage patients with COPD. The aim of this study was to investigate the appropriate intensity of PR exercise training for patients with moderate-to-severe COPD.

Patients and methods

A prospective multicenter randomized controlled trial was conducted from January 2014 to October 2018. The subjects were randomly assigned to three groups with different intensities of PR, according to their maximum oxygen uptake percentage determined by cardiopulmonary exercise testing. After 20 weeks of exercise training, the effects of low-, moderate-, and high-intensity exercise interventions on patients were compared to determine the most appropriate PR prescription.

Results

For patients with moderate COPD, all the measured parameters were significantly improved in the moderate- and high-intensity PR groups (P<0.01), while there was no significant difference in the frequency of acute exacerbations and the mMRC questionnaire after 20 weeks of PR exercise in the low-intensity PR group. For patients with severe COPD, all variables were also improved in the high-intensity PR group (P<0.05), while the mean differences of pre- and post-PR were lower than those in patients with moderate COPD. Moreover, the Hamilton Anxiety Scale and body mass index showed no significant difference in low-intensity PR group (P>0.05).

Conclusion

High-intensity PR exercise is helpful for patients with moderate to severe COPD. Moderate COPD patients need to receive intensive PR training; the improvement degrees from PR intervention were higher than those of the severe COPD patients. For patients with severe COPD, high-intensity PR exercise may be more beneficial if patients can tolerate it.

Prognostic models for outcome prediction in patients with chronic obstructive pulmonary disease: systematic review and critical appraisal

OBJECTIVE

To map and assess prognostic models for outcome prediction in patients with chronic obstructive pulmonary disease (COPD).

DESIGN

Systematic review.

DATA SOURCES

PubMed until November 2018 and hand searched references from eligible articles.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

Studies developing, validating, or updating a prediction model in COPD patients and focusing on any potential clinical outcome.

RESULTS

The systematic search yielded 228 eligible articles, describing the development of 408 prognostic models, the external validation of 38 models, and the validation of 20 prognostic models derived for diseases other than COPD. The 408 prognostic models were developed in three clinical settings: outpatients (n=239; 59%), patients admitted to hospital (n=155; 38%), and patients attending the emergency department (n=14; 3%). Among the 408 prognostic models, the most prevalent endpoints were mortality (n=209; 51%), risk for acute exacerbation of COPD (n=42; 10%), and risk for readmission after the index hospital admission (n=36; 9%). Overall, the most commonly used predictors were age (n=166; 41%), forced expiratory volume in one second (n=85; 21%), sex (n=74; 18%), body mass index (n=66; 16%), and smoking (n=65; 16%). Of the 408 prognostic models, 100 (25%) were internally validated and 91 (23%) examined the calibration of the developed model. For 286 (70%) models a model presentation was not available, and only 56 (14%) models were presented through the full equation. Model discrimination using the C statistic was available for 311 (76%) models. 38 models were externally validated, but in only 12 of these was the validation performed by a fully independent team. Only seven prognostic models with an overall low risk of bias according to PROBAST were identified. These models were ADO, B-AE-D, B-AE-D-C, extended ADO, updated ADO, updated BODE, and a model developed by Bertens et al. A meta-analysis of C statistics was performed for 12 prognostic models, and the summary estimates ranged from 0.611 to 0.769.

CONCLUSIONS

This study constitutes a detailed mapping and assessment of the prognostic models for outcome prediction in COPD patients. The findings indicate several methodological pitfalls in their development and a low rate of external validation. Future research should focus on the improvement of existing models through update and external validation, as well as the assessment of the safety, clinical effectiveness, and cost effectiveness of the application of these prognostic models in clinical practice through impact studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017069247.