Keele Research Repository

Background: Breathlessness is a common presentation in primary care, but GPs may not always record a diagnosis.

Aim: To assess long-term risk of diagnosed COPD, asthma and IHD, and mortality in patients with undiagnosed breathlessness.
Design and Setting: Matched cohort study set within the Clinical Practice Research Datalink.

Method: Adults with first recorded breathlessness between 1997–2010 and no prior diagnostic or prescription record for IHD or a respiratory disease (‘exposed’ cohort) were matched to an ‘unexposed’ cohort. Analyses were adjusted for socio-demographic and co-morbid characteristics.

Results: 75,698 ‘exposed’ patients were followed for a median of 6.1 years, and more than a third subsequently received a diagnosis of COPD, asthma or IHD. In those who remained undiagnosed after six months, there were increased long-term risks of all three diagnoses compared to the ‘unexposed’ cohort. Adjusted hazard ratios for COPD ranged from 8.6 (95%CI 6.8, 11.0) between 6-12 months to 2.8 (2.6, 3.0) after 36 months (asthma 11.7 to 4.3; IHD 3.0 to 1.6). Risk of long-term diagnosis remained higher in the ‘exposed’ cohort with no relevant prescription in the first 6 months, and approximately half of all future diagnoses were made in such patients. Risk of earlier mortality (all-cause and disease-specific) was higher in the ‘exposed’ cohort.

Conclusion: Undiagnosed breathlessness can be an indicator of later COPD, asthma and IHD, and is associated with earlier mortality. There is potential for improved identification at first presentation in primary care of those at high risk of future disease, with careful assessment, appropriate intervention and pro-active follow-up and monitoring.