Time to diagnosis and long-term outcomes for adults presenting with breathlessness

Background There are known delays to diagnosis for diseases which commonly present with chronic breathlessness, but the subsequent impact is unknown. For adults presenting with breathlessness, we investigated the time taken to achieve an explanatory diagnosis, and associations with unplanned hospitalisation and mortality. Methods A retrospective cohort study using the UK CPRD was conducted involving adults with a first-recorded code for breathlessness and no pre-existing cardiorespiratory disease. We documented whether an explanatory diagnosis was recorded after the first code of breathlessness within two years and during all follow-up, and the time to diagnosis. Cox regression (adjusted) was used to investigate the associations with unplanned hospitalisation and mortality. Results 101369 adults were included with a first-recorded code for breathlessness. After two-years, 43394 (43%) adults received a recorded explanatory diagnosis and had a higher risk of unplanned hospitalisation (1.25 [1.19-1.31]) and mortality (2.06 [1.60-2.65]) compared to adults without a diagnosis. Overall, 66909 (66%) adults received a recorded diagnosis during a median of 5-years follow-up. Adults that received a recorded diagnosis after ≥6 months had worse outcomes of unplanned hospitalisation (6-24 months: 1.01 [0.94-1.08]; ≥24 months: 1.13 [1.06-1.20]) and mortality (6-24 months: 3.38 [2.21-5.18]; ≥24 months: 10.80 [7.46-15.70]). Conclusion We describe a sub-group of adults coded for breathlessness but without an explanatory diagnosis with better outcomes. However, in adults with an explanatory diagnosis waiting beyond six months was associated with worse outcomes. Diagnostic pathways for chronic breathlessness need to differentiate between these two groups and achieve earlier diagnosis in those at higher risk. Key messages What is already known on this topic? < Delays to diagnosis exist for chronic cardiorespiratory diseases, but the impact of these delays on future hospitalisation and mortality risk are unknown. What this study adds < Over a median follow-up of 5 years, 1 in 2 people with breathlessness had an unplanned hospital admission and 11% died. < We identify a group of patients with a breathlessness code who did not receive a diagnosis but overall had better outcomes than those with an explanatory diagnosis. < We also report novel findings that for adults who receive an explanatory diagnosis for breathlessness, waiting beyond six months to receive a diagnosis is associated with an increased risk of future unplanned hospital admission and all-cause mortality. How this study might affect research, practice or policy < Further research is needed to prioritise investigations early for patients presenting with chronic breathlessness with increased risk of underlying cardiorespiratory disease. < Diagnostic breathlessness pathways may improve the time to diagnosis and therefore improve longer term outcomes. < Where an underlying causative diagnosis of cardiorespiratory disease is not identified, outcomes appear better, and attention can be focused on reassurance and symptom management.