Nutritional studies in ambulatory oncology patients: impact of malnutrition on survival, patient beliefs, debunking myths, and a novel targeted intervention to attenuate nutritional decline

Malnutrition is highly prevalent among patients diagnosed with cancer, with estimated rates ranging from 31–87%. This unique form of disease-related malnutrition is associated with reduced tolerance to chemotherapy, poor quality of life, and decreased overall survival. Yet despite these debilitating consequences, the most effective way to screening and diagnose patients with malnutrition has yet to be established. This thesis examines the association between the recently published Global Leadership Initiative on Malnutrition (GLIM) criteria and overall survival in a large cohort (n=1405) of patients diagnosed with cancer. This is one of the largest studies to identify the reduced muscle mass phenotypic criterion using gold standard computed tomography (CT) scans, with 40% being diagnosed with malnutrition according to GLIM. This thesis also describes a single-arm, open-label trial which examines the potential benefit of a novel, compact, oncology specific oral nutritional supplement (ONS) enriched with omega-3 fatty acids and vitamin D. Enrolled participants (n=26) were prescribed 2 x 125mls serving of the test product (306 kcals, 18g protein, 1.1g EPA, 0.7g DHA and 10µg vitamin D) for 8-9 weeks. Median energy (kcals) and protein (g) increased significantly from baseline to T2 (after 8/9 weeks). CT analysis of body composition revealed that despite the majority being overweight or obese (81%) according to body mass index (BMI), 67% had an abnormal body composition (cancer cachexia, low muscle density, low muscle attenuation). Misinformation about nutrition and cancer is widespread in the media. This thesis examines the use of biologically-based complementary and alternative medicine (BBCAM) by Irish patients who have been diagnosed with cancer. In 295 participants, BBCAM use increased significantly from 28% pre-diagnosis to 34% post diagnosis (p<0.001). Common types include non-evidence based forms such as high dose vitamin and mineral supplements (84%), dietary supplements (78%) and herbal remedies (49%). These forms of BBCAM can interact with conventional cancer treatment and cause harm to patients. Finally, this thesis describes the publication and dissemination of a novel, evidence-based resource about BBCAM aimed at educating patients who have been diagnosed with cancer. 'The Truth Behind Food and Cancer' is a free resource written by dietitians which aims to debunk common nutrition and cancer myths.

Grantor dc:publisher

University College Cork

Year dc:date.issued

2025

Author dc:creator

• Scannell, Clodagh

Advisors dc:contributor.advisor

• Ryan, Aoife
• Power, Derek

• Nutrition
• Oncology
• Nutritional intervention
• Malnutrition screening
• Dietetics

Statement dc:rights

• © 2025, Clodagh Scannell.

Licence dc:rights.uri

• https://creativecommons.org/licenses/by-nc-nd/4.0/

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10468/17975

OAI identifier oai:identifier

oai:cora.ucc.ie:10468/17975