We’ve recently published a paper in BMC Medical Research Methodology on how cause of death is ICD10 coded in people with asthma. This was a collaboration between myself, Dr. Alexandria Chung (an NHS Lothian Clinical Research Fellow), and George Addo Opoku-Pare, who I was lucky enough to be paired with for the HDRUK Black Internship Program last year. You can read more about that here, and read about George’s experience here.
Our study investigated 91,022 deaths recorded in a Scottish longitudinal linked electronic health record dataset between 2000 and 2017. Asthma-related deaths were identified by the presence of any of ICD-10 codes J45 or J46, in any position. These codes were categorized either as relating to asthma attacks specifically (status asthmatic; J46) or generally to asthma diagnosis (J45).
We found that less than 1% of asthma-related mortality records used both J45 and J46 ICD-10 codes as causes. Infection (predominantly pneumonia) was more commonly reported as a contributing cause of death when J45 was the primary coded cause, compared to J46, which specifically denotes asthma attacks.
Further inspection of patient history can be essential to validate deaths recorded as caused by asthma, and to identify potentially mis-recorded non-asthma deaths, particularly in those with complex comorbidities.