Dyspnoea in COPD patients heralds worse outcomes
medwireNews: Breathlessness is a common finding in patients with chronic obstructive pulmonary disease (COPD) and signals an increased risk of exacerbations, study findings indicate.
The research included 49,438 patients with COPD whose details were included in a UK primary care research database, of whom 82% had been assessed using the Medical Research Council (MRC) dyspnoea scale.
The patients’ mean age was 69.2 years, 46% were women and 33% were current smokers.
In all, 38% had an MRC score of 2, indicating mild dyspnoea, while 46% had a score of 3 or greater, indicating moderate-to-severe dyspnoea, report lead author Hana Müllerová (GlaxoSmithKline R&D, Uxbridge, UK) and team writing in PLoS One.
Compared with patients with less severe disease, those with moderate-to-severe COPD were significantly older (70.7 vs 67.8 years on average), were more often female (48 vs 44%), had worse lung function (44 vs 23% with an FEV1 <50% predicted), had more comorbidities, and were more intensively treated with COPD medications.
They had also been treated more frequently for exacerbations in the previous year (1.0 versus 0.6 events per person per year).
A subgroup of 38,256 patients had 12-month follow-up data available. Analysis of this cohort revealed a positive correlation between dyspnoea grade at baseline and subsequent risk of COPD exacerbations.
For instance, 33% of patients without dyspnoea (MRC grade 1) suffered a moderate-to-severe exacerbation versus 67% of those with MRC grade 5. For severe COPD exacerbations, the figures were 7% versus 24%.
Müllerová and colleagues remark that while breathlessness increased with increasing airflow limitation, one third of patients with only mild airflow obstruction nevertheless had moderate-to-severe dyspnoea.
“In conclusion, dyspnoea on exertion is commonly reported by patients across all levels of airflow limitation,” they write. “The presence of dyspnoea in patients with COPD was associated with markers of greater disease severity and increased risk of poor outcomes.”
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By Joanna Lyford, Senior medwireNews Reporter