Challenges for patient care
Comorbidity is when patients have co-existing health conditions. Comorbidity is common among cancer patients, and with an ageing population, is becoming more so. Comorbidity potentially affects the development, stage at diagnosis, treatment and outcomes of people with cancer.
There is limited consensus on how to record, interpret or manage comorbidity in the context of cancer, resulting in patients with comorbidity being less likely to receive treatment with curative intent. There is evidence that some patients with comorbidity have potentially curative treatment unnecessarily modified, compromising optimal care. Patients with comorbidity have poorer survival, poorer quality of life and higher healthcare costs.
Visit our publications on comorbidity in OUR Archive
Improving management of comorbidity in patients with colorectal cancer
C3 Feasibility Study
This study trialled an intervention aimed at coordinating care and managing comorbidity in patients newly diagnosed with Colorectal Cancer.
This feasibility study piloted a screening tool combined with broad comprehensive medical assessment (CMA) in three centres (Palmerston North, Invercargill and Dunedin) with the aim of improving care coordination, treatment uptake and reducing cancer treatment toxicity.
Colorectal cancer in New Zealand
Colorectal Cancer (CRC) is New Zealand's second most common cancer, affecting predominantly older adults. Seven out of ten patients diagnosed with CRC have at least one other co-existing condition (comorbidity). Evidence suggests patients with comorbidity may have potentially curative treatment unnecessarily modified, with a detrimental impact on their survival. Furthermore their complex health needs often leads to fragmented care. Some small international studies have shown that older patients who undergo Comprehensive Geriatric Assessment (which includes proactive management of comorbidity, evaluation of mental health and functional status) are more likely to complete treatment and have fewer side-effects from chemotherapy.
Cancer care journeys and clinical decision-making
C3 Qualitative Study
There are significant inequalities in cancer survival between Māori and non-Māori, and evidence that comorbidity (the presence of other health problems) and service access play important roles. The C3 Qualitative Study aimed to understand the independent and interacting influences of ethnicity and comorbidity on cancer survival and to develop interventions that will change health delivery to reduce these inequalities.
Methods included recording of multidisciplinary team meetings, 'digital diaries' of patient and clinician perceptions of consultations, and interviews with patients about their cancer journey.
Outcomes of the Study include improved understanding of ethnicity and comorbidity on clinical decision-making about cancer treatment, and cancer journeys, and the development, piloting and evaluation of interventions to reduce these inequalities.
Effect of comorbidity on care and cancer survival inequalities
C3 Quantitative Study
One of the challenges facing the New Zealand health system is how to maintain equitable access to a high-performing health system and eliminate existing health inequalities. The C3 project aimed to address the role of comorbidity and possible unequal treatment in secondary and tertiary care services among Māori with cancer.
Our approach was highly collaborative, actively involving Māori and non-Māori, clinicians, community workers, central and regional health policy and health service delivery professionals, and multidisciplinary. Our focus was on research that informs action with the view to improve equity and quality of care in secondary and tertiary services for Māori cancer patients.
Aims of the Study included:
- Optimise the measurement of comorbidity in the context of Māori patients with cancer
- Describe the epidemiology of comorbidity among Māori and non-Māori cancer patients in New Zealand including patterns by cancer site, deprivation and region and rurality
- Establish the associations of each of ethnicity and comorbidity, with completeness and timing of cancer treatments and survival, adjusted for confounding socio-demographics, and stratified by cancer type
- Determine how ethnicity and comorbidity interact in their association with cancer treatment and survival
- Determine how much of the association of ethnicity with cancer survival is mediated by comorbidities, and explore the extent to which this mediation is due to the impact of comorbidity on the timing and completeness of treatment
- Attempt to model what impact there might be upon survival, if all patients received 'best practice' treatment given comorbidities; and
- Develop and consider feasibility of interventions based on the findings of the two C3 studies, and on review of relevant sources aimed at improving the adequacy and effectiveness of services for Māori cancer patients with comorbidity.