Evaluation of Chemotherapy-induced Dysgeusia in Patients With Gastrointestinal Cancer: A Pilot Study.

BACKGROUND/AIM: Dysgeusia, one of the adverse effects of cancer chemotherapy, and anorexia due to taste disorder can significantly impair the quality of life of patients. However, an evaluation method for dysgeusia has not yet been established. The present prospective study aimed to utilize a combination of subjective and objective assessment methods to evaluate dysgeusia in patients with gastrointestinal cancer initiating chemotherapy, to determine chemotherapeutic drugs and regimens causing dysgeusia, and to assess whether dysgeusia was associated with zinc deficiency. PATIENTS AND METHODS: A total of 21 patients with newly diagnosed gastrointestinal cancer were registered between August 2020 to March 2021. The following regimens were also included in the evaluation if the patients did not develop dysgeusia. A total 30 regimens were administered to the patients during the study period. A salt-impregnated test paper (Salsave®) was used as a subjective assessment, and the chemotherapy-induced taste alteration scale was used as an objective assessment. RESULTS: Based on physician interviews, dysgeusia was diagnosed in 8 of 21 patients (38%) treated with 8 of 30 regimens (27%). All regimens that resulted in dysgeusia contained platinum-based drugs. The patients who developed dysgeusia had higher controlling nutritional status scores at the start of chemotherapy compared to those who did not develop dysgeusia. In both subjective and objective assessments, the patients with dysgeusia performed significantly worse than those without dysgeusia. Six of the eight patients who developed dysgeusia were administered Novelzine, which did not improve the taste disorder despite the improvement of serum zinc levels. CONCLUSION: The combined approach using subjective and objective taste assessment methods was useful in assessing chemotherapy-induced dysgeusia. Mechanisms other than hypozincemia should be considered as contributors to taste disorders caused by platinum-based drugs.

[Mechanisms and Management of COVID-19-Associated Taste Disorders].

The taste buds in the human tongue contain specialized cells that generate taste signals when they are stimulated. These signals are then transmitted to the central nervous system, allowing the human body to distinguish nutritious substances from toxic or harmful ones. This process is critical to the survival of humans and other mammals. A number of studies have shown that dysgeusia, or taste disorder, is a common complication of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which can severely affect patients' nutritional intake and quality of life. Based on the physiological process of taste perception, the direct causes of dysgeusia include dysfunction of taste receptors and damage to the taste nervous system, while indirect causes include genetic factors, aging-related changes, bacterial and viral infections, and cancer treatments such as radiotherapy and chemotherapy. The pathogenic factors of dysgeusia are complicated, further research is needed to fully understand the underlying mechanisms, and some of the reported findings and conclusions still need further validation. All these form a great challenge for clinical diagnosis of the cause and targeted treatment of dysgeusia. Herein, we reviewed published research on the physiological process of taste perception, the potential mechanisms of taste disorders related to SARS-CoV-2 infection, and strategies for prevention and treatment, providing theoretical support for establishing and improving the comprehensive management of COVID-19 complicated by taste disorders.

[Analysis of clinical characteristics in the patient with olfactory disorders].

Objective:To analyze the etiology and clinical features of patients with olfactory disorders （OD） , and to explore the importance of gustatory testing in patients with OD. Methods:Clinical data of 335 consecutive patients with OD who seek medical consultation in the smell and taste center from the year 2015 to 2021 was retrospectively analyzed. The clinical characteristics of patients with OD were analyzed thorough a structured interview of medical history, otolaryngologic examinations, olfactory tests（Sniffin' Sticks test） and gustatory function test（whole-mouth taste test）. SPSS 17.0 software was used to analyze the clinical characteristics of patients with OD and related factors which have effect on gustatory function. Results:Among the patients， 36.4% of them caused by head trauma, 22.1% for upper respiratory tract infection（URTI）, 15.5% for rhinosinusitis diseases（RSD）, 11.9% for idiopathic, 9.6% for congenital anosmia, and 4.5% for other causes, respectively. The features were different in patients with different kinds of OD: most patients with head trauma were anosmic（χ²=27.958, P<0.001）, and no difference was found in gender and age（P>0.05 for both）; most patients with URTI were anosmic（χ²=21.568, P<0.001）, and female patients were more than male（χ²=5.898, P<0.05）, elder patients were more than younger（χ²=12.963, P<0.001）; most patients with RSD were anosmic（χ²=12.106, P<0.05）, and male patients were more than female（χ²=4.655, P<0.05）; elder patients were more than younger for idiopathic OD（χ²=5.284, P<0.05）, but no sex difference was found（P>0.05）; patients with congenital anosmia were all lost their smell since they were born, and no sex difference was found in the disease（P>0.05）. Fifty-seven of 146（39%） patients whose gustation was assessed had gustatory dysfunction. Gustatory function was significantly associated with the causes of OD（r=0.368, P<0.05）, but not related to olfactory function, age and sex（P>0.05 for all）. Conclusion:The leading causes of olfactory dysfunction were head trauma, URTI, RSD, and idiopathic causes. Each of OD had its own distinct clinical features. Gustatory dysfunction were common in patients with OD, and gustatory function was related to the causes of OD. High priority should be given to gustatory function evaluation for the patients with OD.

Photobiomodulation therapy for treatment olfactory and taste dysfunction COVID-19-related: A case report.

It is postulated that the inflammatory process resulting from SARS-CoV-2 infection is the main cause of smell and taste dysfunctions in patients. In view of this, photobiomodulation, due to its anti-inflammatory and antioxidant effects, may be a promising therapeutic modality to treat these disorders. In the present case report, we observed clinical improvement in the symptoms of anosmia and ageusia related to COVID-19 after treatment with photobiomodulation. Due to the inflammatory nature of COVID-19 and the anti-inflammatory effects, photobiomodulation antioxidants already proven in the literature make it a promising therapeutic modality, especially sequela COVID-related, including olfactory (anosmia) and taste (ageusia) dysfunction. In the present case report, the patient's olfactory and gustatory functions were re-established after 10 treatment sessions with photobiomodulation.

Poor Sleep Quality Is Associated with Altered Taste Perception in Chinese Adults.

BACKGROUND: Small clinical studies have suggested that individuals with insufficient sleep could experience taste dysfunction. However, this notion has not been examined in a large-scale, population-based study. OBJECTIVE: This study aimed to examine whether overall sleep quality, as assessed by insomnia, daytime sleepiness, snoring, and sleep duration, was associated with the odds of having altered taste perception in a large population-based study. DESIGN: This was a cross-sectional study that used data from a subcohort of the Kailuan study, an ongoing multicenter cohort study that began in 2006 in Tangshan City, China. PARTICIPANTS/SETTING: The participants were 11,030 adults aged 25 years or older (mean age 53.7 ± 10.7 years), who were free of neurodegenerative diseases. All the participants had undergone questionnaire assessments and medical examinations at Kailuan General Hospital from June 2012 to October 2013. MAIN OUTCOME MEASURES: Altered taste and olfactory perception were assessed via a questionnaire with two questions regarding whether participants had any problems with sense of taste or smell for ≥3 months. STATISTICAL ANALYSES PERFORMED: The association between sleep quality and altered taste/olfactory perception was examined using a logistic regression model, adjusting for age, sex, lifestyle factors (eg, obesity, smoking, alcohol intake, and physical activity) and health status (eg, lipid profiles, blood pressure, modification use, and presence of chronic diseases). RESULTS: Poor overall sleep quality was associated with a higher risk of having altered taste perception (adjusted odds ratio for low vs high sleep quality 2.03, 95% CI 1.42 to 2.91; P < 0.001). Specifically, insomnia, daytime sleepiness, and short sleep duration, but not prolonged sleep duration and snoring, were significantly associated with altered taste perception. A significant association between overall sleep quality and the risk of having altered olfactory perception was also observed (adjusted odds ratio for low vs high sleep quality 2.17, 95% CI 1.68 to 2.80; P < 0.001). CONCLUSIONS: In this population-based study, poor sleep quality was associated with a high likelihood of altered taste perception.

Exploring an Integrative Patient-Tailored Complementary Medicine Approach for Chemotherapy-Induced Taste Disorders.

CONTEXT: Chemotherapy-induced taste disorder (CITD) is a common adverse effect among patients with cancer, with no effective known treatment. OBJECTIVES: Exploring the impact of a patient-tailored complementary and integrative medicine (CIM) treatment program on CITD-related severity. DESIGN: Prospective study on patients' chart. SETTING: Integrative oncology program operating within the Clalit Healthcare Oncology Service in northern Israel. PATIENTS: Patients were referred by their oncology healthcare practitioner to a consultation with a CIM-trained integrative physician (IP). A patient-tailored CIM treatment program was designed, addressing quality of life (QOL)-related concerns which were evaluated using the Edmonton symptom assessment scale (ESAS) and the measure yourself concerns and well-being (MYCAW) questionnaires. RESULTS: A total of 626 patients were referred to the IP consultation, with CITD-related symptoms identified in 43, 34 of them returning for follow-up. The majority of patients treated with CIM reported a reduction in symptom severity (n = 29), with only three reporting no change, 2 an "unclear effect" and none a worsening of CITD-related symptoms. Acupuncture and herbal medicine (sage, carob, and wheatgrass juice, as mouthwash or applied to the oral mucosa) were the most frequently CIM modalities used. Assessment was considered optimal for 18 of the 29 patients who reported an improvement in ESAS scores for fatigue, drowsiness and depression. We conclude that a patient-tailored CIM program is a potentially effective and safe therapeutic option for CITD-related symptoms. Further research is needed in order to explore the impact of CIM treatments on taste and appetite-related concerns during chemotherapy.

Inflammation arising from obesity reduces taste bud abundance and inhibits renewal.

Despite evidence that the ability to taste is weakened by obesity and can be rescued with weight loss intervention, few studies have investigated the molecular effects of obesity on the taste system. Taste bud cells undergo continual turnover even in adulthood, exhibiting an average life span of only a few weeks, tightly controlled by a balance of proliferation and cell death. Recent data reveal that an acute inflammation event can alter this balance. We demonstrate that chronic low-grade inflammation brought on by obesity reduces the number of taste buds in gustatory tissues of mice-and is likely the cause of taste dysfunction seen in obese populations-by upsetting this balance of renewal and cell death.

[A Rare Case of Cerebellar Hemangioblastoma Causing Taste Disorder].

Taste(gustation)is one of the five senses, and comprises the types: sweet, bitter, salty, sour, and umami. Taste disorders, such as dysgeusia and parageusia, are classified into 2 types: those with peripheral origin and those with central origin. The peripheral origin-type taste disorder is caused by zinc deficiency, mouth dryness, a side effect of radiotherapy or complication of systemic diseases such as, diabetes, hepatopathy, and nephropathy. The central origin-type taste disorder is reported to be caused due to demyelinating disease, pontine hemorrhage, pontine infarction, and thalamic infarction; it is very rarely caused by a brain tumor. We surgically treated a 69-year-old man with cerebellar hemangioblastoma who had developed taste disorder. The tumor compressed the solitary nucleus, which includes the taste tract in the central nervous system. On removal of the tumor, the taste disorder gradually improved.

[Impact of Taste Sensitivity on Lifestyle-related Diseases].

Individual taste sensitivity affects one's eating habits, and could thus play a role in the development of lifestyle-related diseases, such as obesity, hypertension and dyslipidemia. However, only a handful of studies have been conducted to investigate these associations. Therefore, we performed taste sensitivity tests on approximately 250 patients with lifestyle-related diseases who were undergoing outpatient treatment at the Department of Internal Medicine, or received a health check-up in order to examine the associations of individual taste sensitivity with their eating habits and lifestyle-related diseases. Our findings showed that sensitivity to sweet or salt taste was significantly lower in patients with cardiovascular diseases, and sensitivity to umami taste was significantly lower in obese patients. These findings suggest that taste sensitivity disorders may be linked not only to eating habits and lifestyle-related diseases, but also to the onset of cardiovascular diseases. Many of the drugs used in the treatment of lifestyle-related diseases and cardiovascular diseases, including antihypertensive agents, statins, fibrates, and allopurinol, are known to form zinc chelates and thereby possibly cause drug-induced taste disorders. Focusing on individual taste sensitivity to improve or maintain intake levels may become a new target for drug development in the areas of lifestyle-related and cardiovascular diseases.

Late sensorial alterations in different radiotherapy techniques for nasopharyngeal cancer.

Intensity-modulated radiation therapy (IMRT) for nasopharyngeal cancer (NPC) allowed a better distribution of the dose to the tumor volume, sparing surrounding structures. Aim of the study is the objective evaluation of olfactory and gustatory impairments in patients who underwent chemo-radiotherapy for NPC. Correlation between smell and taste alterations, xerostomy, and radiation technique was investigated. Thirty healthy subjects and 30 patients treated with chemo-radiation therapy for NPC, with at least a 2-years follow-up period, were evaluated. All subjects underwent symptoms evaluation, endoscopic fiber optic nasal examination, taste strips, Sniffin' sticks tests, Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer late radiation morbidity scoring system. Patients were divided in 2 groups: 2-dimensional radiotherapy/conformal 3-dimensional radiotherapy and IMRT. A higher percentage of rhinorrhea, nasal obstruction, xerostomy, hyposmia, hypogeusia, mucosal hyperemia, and presence of nasopharyngeal secretions was found in irradiated subjects (P < 0.05). Concerning olfactory and gustatory scores, we demonstrated a statistically significant difference between healthy subjects and irradiated patients (P < 0.05), with lower gustatory total score in IMRT group (P < 0.01). In conclusion, chemo-radiotherapy for NPC induces long-term smell and taste impairments, which can compromise quality of life. Although based on small samples, it is also important to consider that IMRT can induce higher taste dysfunction compared with traditional techniques.

Taste disorders in myasthenia gravis: a multicenter cooperative study.

BACKGROUND AND PURPOSE: The purpose of the present study was to investigate the prevalence and clinical characteristics of taste disorders in patients with myasthenia gravis (MG). METHODS: We studied 371 Japanese patients with MG (127 men and 244 women; mean age, 56.6±16.9years) consecutively evaluated between May and September 2010 in six neurological centers comprising the East Japan MG Study Group. Ninety-three patients (25%) had thymoma. We interviewed all patients to determine whether they had taste disorders during the clinical course of MG and then further evaluated the patients with MG, who reported having taste disorders, using a questionnaire. RESULTS: Taste disorders were observed in 16 (4.3%) of the 371 patients with MG. We concluded that taste disorders in 2.4% of patients with MG excluding other factors were associated with MG itself. All patients had thymoma with seropositivity for anti-acetylcholine receptor antibodies. Thymoma tended to be advanced, and four patients with Masaoka stage IVa required radiation therapy or chemotherapy. Five patients noticed taste disorders 2-3 months before the onset of MG. Sweet taste loss was more common than salty, bitter, and sour taste loss. CONCLUSIONS: This was the first systematic survey of taste disorders in patients with MG by a multicenter study. Taste disorders were more common in the present sample of patients with MG than in the general population.

Taste damage (otitis media, tonsillectomy and head and neck cancer), oral sensations and BMI.

Otitis media and tonsillectomy are associated with enhanced palatability of energy dense foods and with weight gain. Otitis media can damage the chorda tympani nerve (CN VII); tonsillectomy and head and neck radiation treatment can damage the glossopharyngeal nerve (CN IX). Both of these nerves function prominently in taste sensation. The present study utilizes these sources of damage to study central interactions among the nerves that mediate oral sensations. Mild damage restricted to one of these nerves can actually intensify sensations evoked from undamaged nerves (i.e., whole-mouth taste, oral tactile sensations evoked by fats and irritants). These intensifications may result from disruption of central inhibitory taste circuits, as taste damage appears to disinhibit other oral sensory nerves. In addition, mild damage restricted to one taste nerve can intensify odors perceived from foods in the mouth during chewing and swallowing (i.e., retronasal olfaction); this may be a secondary consequence of the intensification of whole-mouth taste. Damage to both nerves leads to widespread oral sensory loss. At present, the link between sensory alterations and weight gain has not been established for adults (e.g., does increased fat preference occur in individuals with oral sensory intensifications, those with losses, or both?). Finally, pain in non-oral locations is also related to taste loss. When participants rated "the most intense pain of any kind they had ever experienced," those with the greatest taste loss gave the highest ratings. These effects suggest that taste loss significantly influences long-term health outcomes.

Understanding taste dysfunction in patients with cancer.

Taste dysfunction is a significant but underestimated issue for patients with cancer. Impaired taste results in changes in diet and appetite, early satiety, and impaired social interactions. Nurses can play a key role in educating patients and families on the pathophysiology of taste dysfunction by suggesting interventions to treat the consequences of taste dysfunction, when available, and offering psychosocial support as patients cope with this often devastating consequence of treatment. Taste recognition helps humans identify the nutritional quality of food and signals the digestive tract to begin secreting enzymes. Spoiled or tainted foods typically are recognized by their bad taste. Along with the other sensory systems, taste is crucial for helping patients treated for cancer feel normal. This article will review the anatomy and physiology of taste; define the different types of taste dysfunction, including the underlying pathophysiologic basis related to cancer treatment; and discuss potential nursing interventions to manage the consequences of taste dysfunction.

Significant association of deficiency of hemoglobin, iron and vitamin B12, high homocysteine level, and gastric parietal cell antibody positivity with atrophic glossitis.

BACKGROUND: Atrophic glossitis (AG) is considered to be a marker of nutritional deficiency. In this study, we evaluated whether there was an intimate association of the deficiency of hemoglobin, iron, vitamin B12 or folic acid, high blood homocysteine level, and serum gastric parietal cell antibody (GPCA) positivity with AG. METHODS: The blood hemoglobin, iron, vitamin B12, folic acid, and homocysteine concentrations and the serum GPCA level in 176 AG patients were measured and compared with the corresponding levels in 176 age- and sex-matched healthy control subjects. RESULTS: We found that 39 (22.2%), 47 (26.7%), 13 (7.4%), and 3 (1.7%) AG patients had deficiencies of Hb (men < 13 g/dl, women < 12 g/dl), iron (<60 µg/dl), vitamin B12 (<200 pg/ml), and folic acid (<4 ng/ml), respectively. Moreover, 38 (21.6%) AG patients had abnormally high blood homocysteine level, and 47 (26.7%) AG patients had serum GPCA positivity. AG patients had a significantly higher frequency of Hb, iron, or vitamin B12 deficiency, of abnormally elevated blood homocysteine level, or of serum GPCA positivity than healthy control subjects (all P-values = 0.000). However, no significant difference in frequency of folic acid deficiency was found between AG patients and healthy control subjects. CONCLUSION: We conclude that there is a significant association of deficiency of hemoglobin, iron and vitamin B12, abnormally high blood homocysteine level, and serum GPCA positivity with AG.

[Investigation for relation of gustatory and olfactory impairment in patients receiving cancer chemotherapy].

Because it is considered that there is a close connection between gustation and olfactation, and that a decline in the function of either sensation influences the other one, it would be useful to clarify the relation between gustatory and olfactory disorders in patients receiving cancer chemotherapy. Therefore, we investigated the frequency of gustatory and olfactory disorders in patients administered anticancer drugs at the Division of Outpatient Chemotherapy of Kanazawa University. Among 136 patients who consented to participate in the investigation, 75 patients (55%) complained of a gustatory disorder, and 26 patients (19%) complained of an olfactory disorder. The occurrences of olfactory disorder were significantly greater in patients who had gustatory disorder than in patients who did not. The expression frequency of gustatory disorders was significantly higher among those taking docetaxel (85%) when compared with patients on other regimens. Although not statistically significant, the incidence of olfactory disorder was higher in patients taking docetaxel (31%), irinotecan+l-leucovorin (l-LV)+5-fluorouracil (5-FU) (31%), l-oxaliplatin+l-LV+5-FU (28%), trastuzumab (23%), and weekly paclitaxel (22%). Medical staff should recognize that olfactory disorders are similar to gustatory disorders, as they both have adverse reactions induced by anticancer drugs.

Evaluation of gustatory function in patients with diabetes mellitus type 2.

OBJECTIVES: The aim of this study was to evaluate the gustatory function of patients with diabetes mellitus type 2 and to compare gustatory appreciation on right and left sides of the tongue and soft palate. STUDY DESIGN: The study group was composed of 40 controlled and 40 uncontrolled diabetes mellitus type 2 patients. A group of 40 age- and gender-matched healthy control subjects were also evaluated. Gustatory function was tested by administering a whole-mouth above-threshold test and spatial taste test using sucrose, sodium chloride (NaCl), citric acid, and quinine hydrochloride solutions. Statistical analysis was performed using 1-way ANOVA and Student t test. RESULTS: Taste impairment was found in the controlled and uncontrolled diabetic patients relative to healthy control subjects (P < .0001). A highly significant difference was noticed for sweet (P = .00001) and sour (P = .00002) tastes. For salt taste, a significant difference was found (P = .001). Hypogeusia was reported among 50 (62.5%) of the diabetic patients versus 5 (12.5%) of control subjects (P < .0001). Ageusia to sweet was found in 6 uncontrolled diabetic patients (P < .0001). For almost all 120 subjects, taste sensitivity was found to be equivalent on left and right sides of the tongue and soft palate. CONCLUSION: Type 2 diabetic patients had a blunted taste response for sweet followed by sour and salt tastes. This taste abnormality may influence the choice of nutrients, with a preference for sweet-tasting foods, thereby exacerbating hyperglycemia.

Cancer chemotherapy: sometimes takes the pleasure out of eating.

(1) In June 2006 the French National Cancer Institute published the results of a survey of eating difficulties among 1843 patients receiving cancer chemotherapy; (2) More than one-third of patients said they had less appetite than before ("far less" in 13% of cases). About half of patients said they had noticed a change in their sensation of thirst; (3) Half of patients who had been receiving treatment for at least 6 months said they had lost weight; (4) Half of patients found food tasted different. 43% of patients found certain odours unbearable, especially perfumes and tobacco. One-third of patients said the smell of the treatment room made them nauseous. Many patients found mealtimes unpleasant, sometimes even a source of anxiety; (5) In practice, these eating difficulties should be taken into account when assessing the risk-benefit balance of cancer treatments. When a treatment needs to be pursued, patients should be helped to find ways of making food more palatable, the treatment room should be well ventilated, and perfumes should not be used.

Leukemia case in patient with taste dysfunction.

A blood examination was carried out in order to assess the serum zinc level in a patient with taste dysfunction. A blood cell count was also performed simultaneously and promyelocytic leukemia was identified. This case provides an example of leukemia being detected at the time of a blood test being given to assess taste dysfunction.

[Taste disorders]. / Les troubles du goût.

PURPOSE: This review focuses on the present state of the question about taste disorders with reference to their associated factors, diagnostic methods, and potential effects. CURRENT KNOWLEDGE AND KEY POINTS: Taste disorders may be induced by many drugs and are associated to a number of acute or chronic diseases. Patients may be asked about their taste complaints, and taste thresholds may be determined by electrogustometry or chemical gustometry. Taste impairment may provide a good indicator to the course of some diseases such as diabetes mellitus in which hypogeusia predicts occurrence of degenerative complications. Dysgeusia may induce nutritional disorders and contribute to wasting in chronic liver disease, cancer, or human immunodeficiency virus infected patients. Mechanisms involved in dysgeusia are more than one in a patient. Taste disturbance may be secondary to a variety of causes that include zinc deficiency, lesions of the lingual epithelium, neurological impairment, and a pharmacological effect. FUTURE PROSPECTS AND PROJECTS: A better understanding of the transduction mechanisms of the gustatory signal and the main pathogenic factors involved in dysgeusia may possibly improve the follow-up of the concerned patients notably in terms of nutritional status.