Alteration in taste perception and its relationship with nutritional status and quality of life in patients with advanced cancer.
Conducted within the hospice setting, this unique study assessed the prevalence of altered
taste perception and its potential relationship with nutritional status in a group of 56
advanced cancer patients who had not received any recent radiotherapy or chemotherapy,
compared to 46 age matched healthy controls. An assessment was made of the impact of
altered taste perception on quality of life in this group of cancer patients. Taste perception
was objectively measured using the International standard for sensory appraisal (lSOI991)
and nutritional status assessed using upper arm anthropometry, bioelectrical impedance
analysis, weight and hand grip dynanometry. A 3-day weighed intake technique was used
to estimate dietary intake, and quality of life assessment was based on the Hospital Anxiety
and Depression scale (Zigmund and Snaith, 1983). Results indicate that cancer patients
exhibited lower 'bitter' thresholds (increase bitter taste sensitivity) compared to age
matched controls an effect which was not related to tumour type. Results of this study also
highlight the impact that changes in taste perception have on quality of life, which is
pivotal in the appropriate management of altered taste perception in palliative care.
Heightened olfactory perception was also evident in cancer patients exhibiting heightened
gustatory perception. Biochemical analysis suggests that Tumour Necrosis Factor a and
associated acute phase response may be associated with increased bitter taste sensitivity.
Within the cancer group, heightened bitter perception was associated with a reduced
protein intake. These results have demonstrated that in a terminally ill group, dietary
management should focus on altered taste perception, aiming to maximise quality of life.
Based on these results, a 4-week intervention was undertaken using omega 3 fatty acid
(fish oil capsules) in a subsequent group of advanced cancer patients, aimed at
manipulating the acute phase response and lNFa production. This demonstrated no
changes in taste perception. However, the intervention was associated with attenuation of
weight loss and an alteration in fatty acid composition of lipid membrane. These
preliminary results suggest the value of further studies to investigate the effects of omega 3
fatty acids on taste perception and other associated symptoms in cancer patients. Moreover,
the challenges to recruitment and retention of patient in studies in the terminally ill are