Abstract

Background Expediting cancer diagnosis is a priority in many countries. The rising prevalence of chronic conditions may complicate the cancer diagnostic process. We investigated whether patients with pre-existing morbidity were more likely to experience disadvantage in cancer diagnostic outcomes and processes.

Methods We used linked primary, secondary care, and cancer registration data for patients aged 40+ years diagnosed with incident cancer in England during 2012-2018. The Cambridge Multimorbidity Score quantified morbidity burden. Logistic regressions investigated whether morbidity burden was associated with stage at diagnosis, 30-day all-cause mortality, emergency presentation- or urgent suspected cancer referral route to diagnosis.

Results 288,297 patients were included. Decreasing morbidity burden was associated with an increased likelihood of advanced-stage diagnosis (e.g. high burden vs. no burden aOR: 0.72, 95% CI: 0.7-0.75, p<0.0001). There were u-shaped relationships between morbidity burden, emergency diagnoses and 30-day mortality, with those with high or no morbidity burden most likely to be diagnosed as an emergency and to die within 30 days after diagnosis. Diagnoses via urgent suspected cancer referrals decreased with increasing morbidity burden. Associations varied across cancer sites, though higher morbidity burden was not associated with advanced stage for any cancer.

Conclusion Contrary to expectations, not having pre-existing morbidities was associated with an increased risk of advanced-stage diagnosis and emergency presentations. This may reflect heightened surveillance of patients with morbidity being protective against later advanced-stage cancer diagnoses. These findings highlight the need for robust cancer surveillance processes and good comprehensive care that considers cancer alongside wider aspects of health.

Competing Interest Statement

All authors declare: all authors, apart from S Moore, had financial support from NIHR for the submitted work; GL is supported by a Cancer Research UK Fellowship C18081/A18180. SWDM is supported by the NIHR Manchester Biomedical Research Centre (NIHR203308). SM is supported by a doctoral fellowship for primary care clinicians awarded by Wellcome, grant number PMHG1A4; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.

Funding Statement

This work was supported by the NIHR Programme Grants for Applied Research (PGfAR) SPOtting Cancer among Comorbidities (SPOCC) programme: supporting clinical decision making in patients with symptoms of cancer and pre-existing conditions [NIHR 201070]. The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. The funder had no role in study design, data collection, analysis, interpretations, or writing of the report.

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:

The National Research Ethics Service (NRES) has granted ethical approval for observational research using anonymised CPRD data. Observational studies using anonymised CPRD data are therefore not required to obtain study-specific ethical approval. Study protocol approval was granted by the CPRD Independent Scientific Advisory Committee (protocol 20_126R).

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

AbbreviationsCPRDClinical Practice Research DatalinkNCRASNational Cancer Registration and Analysis ServiceHESHospital Episode StatisticsIMDIndex of Multiple DeprivationONSOffice for National StatisticsNRESNational Research Ethics ServiceNIHRNational Institute for Health and Care ResearchPPIPatient and Public InvolvementSPOCCSPOtting Cancer among ComorbiditiesTNMTumour, Node, MetastasisCMSCambridge Multimorbidity ScoreGPGeneral PractitionerACGAdjusted Clinical Groups