Abstract
As improved healthcare leads to older populations, individuals will increasingly experience multiple diseases, possibly concurrently (multimorbidity). This article explores whether age and established risk factors are sufficient to explain the incidence rates of multiple, possibly coexisting diseases. By accounting for the limited age-range in UK Biobank data, previous work demonstrated that a Weibull model could accurately describe the incidence of ∼60% of the most common primary hospital diagnoses of diseases. These are used here to predict the age-dependent incidence of diseases with adjustment for established risk factors. A “Poisson binomial” model is combined with these to predict the total number of occurrences of each disease in the UK Biobank cohort that would be expected without pre-existing (prior) disease. For 123 diseases in men and 99 diseases in women, the total observed new cases of each disease (including those from individuals with pre-existing diseases and multimorbidity), were found to be approximately 1.5 times greater than that predicted for individuals without prior disease, and could not be explained by natural statistical variation. The multiple of 1.5 was sufficiently consistent across different diseases to prevent its use for classification of disease types, but there were differences for sub-groups such as smokers with high body mass index, and for some classes of disease (as defined by the International Classification of Diseases version 10). The results suggest that empirical modelling might allow reliable predictions of primary causes of hospital admissions, helping to facilitate the planning of future healthcare needs.
Competing Interest Statement
The authors have declared no competing interest.
Funding Statement
This research was supported by an intermediate research fellowship from the Nuffield Department of Population Health (NDPH), University of Oxford.
Author Declarations
I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.
Yes
The details of the IRB/oversight body that provided approval or exemption for the research described are given below:
UK Biobank data can be accessed by application through www.ukbiobank.ac.uk. UK Biobank obtained participant's consent for the data to be used for health-related research, and all methods were performed in accordance with the relevant guidelines and regulations.
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Yes
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Footnotes
Minor changes to text and title, plus inclusion of a new figure and paragraph to discuss it. Changes made with the intention of making the topic, results, and reporting clearer.
Data Availability
UK Biobank data can be accessed by application through www.ukbiobank.ac.uk.