Of potential prognostic variables for COPD to use in a multidimensional staging tool, BMI, severity of airflow obstruction (FEV1% predicted) and the MRC Dyspnoea Score (BOD) have been shown to be useful for a more complete assessment of the impact of the disease.1 In 1999–2002 we identified 431 patients (208 women) with COPD in primary care surgeries and recorded their BOD scores (maximum 7). For men and women (mean±SD): age was 66±10 and 64±10; pack/years 34±19 and 34±18; BMI 27±5 and 25±6; FEV1% predicted 55±15 and 57±16; and MRC Dyspnoea Score 2.6±1.0 and 2.6±1.0; with BOD scores 1.9±1.5 and 2.0±1.6 respectively. The low mean BOD scores indicate the mainly moderate severity for this primary care cohort (only one subject had an MRC score of 5). Because of the similarities in these variables for men and women further analysis is of the whole cohort. Mortality was assessed in October 2010 and a Kaplan–Meier analysis for those with BOD scores 0 and 1 shows 80% and 75% probability of survival, whereas for a BOD score of >4 the 10-year survival was <20%. By way of contrast GOLD stages 1 and 2 had a 75% and 60% survival with Stage 4 showing a 60% survival. The Cox regression model (Abstract P219 table 1) demonstrated that BOD was a better predictor of survival than age and that smoking history was a significant covariate. Ten year survival was <10% when smoking history (with age and co-morbidity score) was added to a BOD score of >4 in a Kaplan–Meier plot.Conclusion
BOD, a multidimensional index of the clinical impact of COPD is valid for a 10-year prognosis and outperforms GOLD staging over that period.