Gustatory Function Research Articles

Olfactory and Gustatory Function in Early-Stage Parkinson's Disease: Implications for Cognitive Association.

Olfactory and Gustatory Function in Early-Stage Parkinson's Disease: Implications for Cognitive Association.

Fungiform Papillae and Gustatory Function in Neurofibromatosis Type 1: A Case-Control Study.

Fungiform papillae enlargement is a common oral manifestation of neurofibromatosis type 1 (NF1). This study aimed to objectively evaluate the size, number, and symmetry of fungiform papillae in NF1 individuals and investigate the relationship between these alterations and taste perception, salivary flow, dietary habits, and BMI. A cross-sectional case-control study was conducted on 80 participants (40 with NF1 and 40 controls), matched by age and sex. Participants underwent quantitative and morphological evaluation of fungiform papillae, gustatory perception tests, sialometry, saliva analysis, xerostomia assessment, dietary assessments, and Body Mass Index calculations. The NF1 group exhibited significantly larger and more asymmetric fungiform papillae and exhibited a higher detection threshold for sweet and sour tastes, as well as hyposalivation and lower preference for healthy foods compared to the controls. No correlation was found between papillae morphology, gustatory perception tests, saliva properties, xerostomia, food preferences, or BMI in the NF1 group. Enlarged and asymmetric fungiform papillae, hyposalivation, heightened sensitivity to sweet and sour tastes, and reduced healthy eating habits were common in NF1. Although fungiform papillae alterations seem unrelated to taste sensitivity and food preferences, further investigation is needed to better understand the mechanisms underlying these changes.

Extragustatory bitter taste receptors in head and neck health and disease.

Taste receptors, first described for their gustatory functions within the oral cavity and oropharynx, are now known to be expressed in many organ systems. Even intraoral taste receptors regulate non-sensory pathways, and recent literature has connected bitter taste receptors to various states of health and disease. These extragustatory pathways involve previously unexplored, clinically relevant roles for taste signaling in areas including susceptibility to infection, antibiotic efficacy, and cancer outcomes. Among other physicians, otolaryngologists who manage head and neck diseases should be aware of this growing body of evidence and its relevance to their fields. In this review, we describe the role of extragustatory taste receptors in head and neck health and disease, highlighting recent advances, clinical implications, and directions for future investigation. Additionally, this review will discuss known TAS2R polymorphisms and the associated implications for clinical prognosis.

Comparative Analysis of Taste Perception Among Airline Pilots, Construction Workers, and Office Employees.

Objective Occupational exposures may influence gustatory sensations through mechanisms such as fatigue, acute or chronic stress, circadian rhythm disruptions, and exposure to various chemicals. In this cross-sectional study, we sought to compare taste perception across three professional groups, namely airline pilots, construction workers, and office employees, by assessing taste identification times for sweet, salty, sour, and bitter flavors, alongside salivary pH levels. Methods The study cohort consisted of 90 healthy male participants, with 30 individuals in each occupational group, matched for age and professional experience. Salivary pH was measured using pH meter paper, whereas taste identification times were assessed using aqueous solutions applied to dissolvable strips for each taste. Results There were no significant differences in salivary pH among the study groups. However, airline pilots exhibited a significantly longer identification time for sweet taste (9.8 ± 3.9 seconds) compared to construction workers (7.0 ± 3.1 seconds, P < 0.05) and office employees (7.1 ± 3.3 seconds, P < 0.05). Conversely, construction workers demonstrated a significantly prolonged identification time for sour taste (6.1 ± 2.9 seconds) compared to pilots (4.2 ± 2.6 seconds, P < 0.05) and office employees (4.6 ± 2.5 seconds, P < 0.05). No significant differences were observed in the identification times for salty and bitter tastes across the groups. Conclusion We found significant differences in taste perception among airline pilots, construction workers, and office employees, particularly concerning sweet and sour tastes. These findings suggest that occupational factors may influence gustatory function in a complex manner. Further research is warranted to explore the underlying mechanisms and potential implications for dietary habits and health within specific occupational groups.

Gustatory Function in Patients With Cerebellopontine Angle Masses.

To investigate the impact of cerebellopontine angle (CPA) masses on subjective and measured taste function. Retrospective cross-sectional study. Tertiary referral center. Consecutive adult patients with untreated CPA masses. Gustatory function was psychophysically measured with Taste Strips (range, 0-16) on both sides of the tongue. Subjective taste complaints were assessed using a questionnaire. Half-sided taste impairment (hemi-ageusia) was defined as side-to-side asymmetry ≥4 points with <9 points on the side of the CPA mass. We used the Koos classification for vestibular schwannomas (VS) and, in the case of facial nerve palsy, the House-Brackmann grading system. We included 135 patients (mean [standard deviation (SD)] age, 55.3 ± 14.1 yr; 62 males). The most common CPA mass was VS (77%). Overall, the measured taste function was lower on the affected compared with the healthy side of the tongue (mean score, 9.8 ± 3.3 versus 11 ± 2.9; p < 0.0001). Looking for clinically relevant one-sided taste impairment revealed 18 (13.3%) patients with hemi-ageusia, but only 4 (30.8%) of those subjectively complained of taste dysfunction. Regarding VS, Koos IV masses presented the lowest score on the affected side (mean score, 7.5 ± 3.7). Six patients presented with facial palsy. Having facial palsy did not result in a lower Taste Strips score (p = 0.23). Before any CPA mass treatment, a measurable ipsilateral decrease in gustatory function is present in many patients. Most patients do not notice this preexisting taste impairment. From a medicolegal standpoint, this warrants consideration. To avoid postoperative claims regarding taste function, a preoperative assessment may be considered.

Smell and Taste Alterations in Patients Receiving Curative or Palliative Chemotherapy-The CONKO 021-ChemTox Trial.

Previous data regarding chemotherapy-induced olfactory and gustatory dysfunction (CIOGD) are heterogeneous due to inconsistent study designs and small numbers of patients. To provide consistent, reliable data, we conducted a cohort study using standardized testing. Patients diagnosed with lymphoma, leukemia, or gastrointestinal malignancies were examined up to five times (T1 to T5), beginning prior to chemotherapy. We examined patients receiving temporary treatment up to 12 months post-therapy. Clinical assessment included extensive questionnaires, psychophysical tests of olfactory and gustatory function, and measurement of peripheral neuropathy. Statistical analysis included non-parametric tests to evaluate the longitudinal development of CIOGD. Our data (n = 108) showed a significant decline in olfactory and gustatory testing during chemotherapy (p-values < 0.001). CIOGD appeared stronger among patients above 60 years, while sex did not matter significantly. However, we identified distinct associations between CIOGD and reported anorexia as well as with higher neuropathy scores. Self-assessment appeared less sensitive to chemosensory dysfunction than psychophysical testing. Post-therapy, olfactory and gustatory function regenerated, though baseline levels were not attained within 6 to 12 months. In conclusion, our data highlight the wide prevalence and slow recovery of CIOGD. Understanding CIOGD as a potential neurotoxic effect may disclose new therapeutic prospects.

Gustatory Function in Patients with Chronic Rhinosinusitis with Nasal Polyposis

Abstract Background Many patients with chronic rhinosinusitis (CRS) describe disturbances in taste. Recent research has shown that taste receptors in airway epithelial cells are involved in defending against upper respiratory tract infection. The aim of the present study was to investigate gustatory function in patients with chronic rhinosinusitis (CRS). Methods Taste function was assessed using the taste strip test in 63 patients with CRS (Study Group) (mean age was 42.05± 14, ranging between 19 to 68 years. More than half of cases (68.3%) were males) and 63 healthy controls (The mean age was 40.9± 13.6, ranging between 18 to 67 years. More than half of cases (68.3%) were males). Results The mean Sweet, Salt, Sour, Bitter, and Umami score among the study group was 3.6± 0.6, 3.9± 0.3, 3.8± 0.4, 3.4± 0.8, 3.5± 0.7 and 18.4± 2.6 respectively with a median equal to 4 among all of them. The mean total Taste score was 18.4± 2.6 with a median of 20 while The mean Sweet, Salt, Sour, Bitter, and Umami score among control group was 4± 0, with a median equal to 4 among all of them. The mean total taste score was 20± 0 with a median of 0 Conclusion Taste dysfunction is a common complaint in CRS. Patients with CRS have decreased gustatory function.

Effect of Corona Virus on Olfactory &amp; Gustatory Functions (Systematic Review Study)

Abstract Background Because of the rapid spreading of severe acute respiratory syndrome coronavirus 2 (SARS- CoV-2) infection, the Coronavirus disease 2019 (COVID-19) outbreak was characterized as a pandemic by the WHO on March 11, 2020. Materials and Methods Following the PRISMA statement guidelines, we conducted this systematic review and meta-analysis according to the Cochrane handbook of systematic reviews of intervention. We searched PubMed, Scopus, Cochrane, and Web of Science, Embase, and Science Direct till December 2021 with relevant keywords. We included the whole clinical studies assessing olfactory and/or gustatory dysfunctions (OGD) in patients with COVID-19, studies including patients with a confirmed diagnosis of COVID-19 by a positive result of RT-PCR were included, studies that assessed the OGD by either subjective evaluation were also included, studies written in English languages only, all of the studies must have been written in English as a full-text manuscript, double or single-arm designs. Results A total of 12 studies were finally included for the final qualitative and quantitative analysis illustrating the association and the relationship between COVID-19 infection and olfactory and gustatory functions. The mean age of the participants was 49.12 years. The pooled analysis of the included studies showed a significant association of positive results between OGD and COVID-19 infection. Also, the analysis showed a significant association of positive results between either isolated olfactory or gustatory dysfunction and COVID-19 infection. Regarding the association between gustatory dysfunction in COVID-19 patients versus (Acute respiratory infection) ARI patients with no detectable virus, the analysis showed a significant difference between COVID-19 patients and ARI patients with no detectable virus regarding the gustatory dysfunction meaning there is a high association between gustatory dysfunction and COVID-19 patients other than ARI patients with no detectable virus. Finally, the pooled analysis of the included studies showed a significant difference between COVID-19 patients and ARI patients with other respiratory viruses (ORV) in terms of OGD. Conclusion Based on the available evidence, there are regional and chronological differences in the prevalence rates of olfactory and gustatory dysfunction. Future studies, particularly those that document the temporal relationship in the onset of these 2 symptoms, are needed.

Adherence to mediterranean diet and aromatic plants intake are related with gustatory function: A case-study from a Portuguese region

The Mediterranean Diet has been recognized as one of the healthiest and most sustainable dietary patterns and is flavor rich due to the use of different seasonings, such as aromatic plants, in dish confection. Based on the hypotheses that: 1) gustatory function will affect food choices; 2) seasoning flavors may be differently accepted according to individuals’ gustatory functions; the aim of the present study was to assess the association between taste sensitivity and/or preference with Mediterranean Diet adherence and seasoning consumption. A total of 383 adults (18–59 years old; 198 female, 185 male) from North Alentejo region of Portugal were enrolled in this study, with 291 (145 female and 146 male) also evaluated for gustatory function. Recognition thresholds were obtained for four tastes (sweet, sour, salty, and bitter) and astringency, as well as preference level for the highest concentration of each stimulus tested. A validated Food Frequency Questionnaire was filled out, and MD adherence was extrapolated from the answers of the Food Frequency Questionnaire according to the Mediterranean Diet Adherence Screener (MEDAS) score.In total, 20.8% of the individuals presented low, 58.2% medium, and 21.0% high adherence. Adherence was higher in women than men and in older individuals than younger adults. Adherence to the Mediterranean Diet was positively correlated with aromatic plants consumption but not spices. Seasonings were associated with gustatory function, and the cluster with higher consumption presented higher preferences for bitter and salty tastes. Total sodium intake was also higher in this cluster, suggesting that these individuals prefer stronger oral sensations. In conclusion, this study shows that MD adherence is not high, even in regions with rural characteristics. The observed association of MD and seasoning intake with gustatory function do underline the usefulness of this information in strategies aimed at promoting healthy and sustainable eating patterns.

Association of Olfactory and Gustatory Function with Memory among Community-Dwelling Independent Older Adults.

This study examined the association between memory function and reduced olfactory and gustatory function among independent community-dwelling older adults. This cross-sectional study included 127 older adults (65.4% women). We assessed their memory, odor, and taste identification skills. Open essence (OE) test and taste strips (TS) were used to identify hyposmia (OE test ≤6) and hypogeusia (TS test ≤8), respectively. Participants with severe hyposmia had significantly poorer memory functions compared to participants without severe hyposmia. After adjusting for covariates, multivariate logistic regression models revealed a significant association between immediate recognition performance and a decreased likelihood of severe hyposmia (odds ratio=0.65; 95% confidence interval 0.47-0.90). We observed no significant association between taste function and memory. Memory function may be associated with olfactory impairment in older adults.

Correlations between Gustatory, Olfactory, Cognitive Function, and Age in Healthy Women.

Aging is a progressive physiological degeneration associated with a decline in chemosensory processes and cognitive abilities and a reduction in synaptic plasticity. The biological bases of ageing are still not completely understood, and many theories have been proposed. This study aimed to evaluate the occurrence of age-related changes affecting the chemosensory function (gustatory and olfactory) and general cognitive abilities and their potential associations in women. To this aim, 319 women (the age ranging from 18 to 92 years) were recruited and divided into four different age groups: 18-34 years, 35-49 years, 50-64 years, and ≥65 years. Our results confirmed that in women, gustatory, olfactory, and cognitive functions decline, though in a different manner during aging. Olfactory and cognitive function showed a slight decline along the first three age classes, with a dramatic decrease after age 65 years, while gustatory function decreased more gradually. Olfactory and gustatory deficits may have a high degree of predictivity for general cognitive function as well as for specific cognitive subdomains such as visuospatial/executive abilities, language, memory, and attention. Our study highlighted the importance of using chemosensory assessments for the early diagnosis of cognitive decline and for the development of appropriate personalized risk prevention strategies.

Subjective versus Psychophysical Measures of Chemosensory Alterations following COVID-19

Introduction: Olfactory dysfunction is a common symptom of COVID-19. However, subjective perception of olfactory function does not always correlate well with more objective measures. This study seeks to clarify associations between subjective and psychophysical measures of olfaction and gustation in patients with subjective chemosensory dysfunction following COVID-19. Methods: Adults with persistent COVID-19-associated chemosensory disturbance were recruited for a prospective, longitudinal cohort study at a tertiary care institution. Participants provided subjective measures of olfactory and gustatory function and underwent psychophysical assessment using Sniffin’ Sticks olfactory and Monell gustatory tests. Results: Data analysis (n = 65) showed a statistically significant association between subjective and psychophysical measures of olfaction (p < 0.001). For each one-point increase in subjectively-reported olfactory ability, there is, on average, a 0.11 (95% CI: 0.06, 0.16; p < 0.001) point increase in TDI score while adjusting for age at baseline assessment, sex, and follow-up time. For each one-point increase in subjectively-reported olfactory ability, there is, on average, a 0.04 (95% CI: 0.02, 0.06; p < 0.001) point and 0.05 (95% CI: 0.03, 0.07; p < 0.001) point increase in discrimination and identification scores, respectively, when adjusting for age at baseline assessment, sex, and follow-up time. Conclusion: Subjective olfaction shows a mild to moderate association with psychophysical measures, but it fails to comprehensively assess persistent COVID-19-associated chemosensory deficits. The lack of significant association between subjective olfaction and threshold limits the utility of subjective olfaction in tracking recovery. These findings support the push for more widespread psychophysical chemosensory testing.

Taste assessment as a part of geriatric nutritional care: Potential implications for clinical practice

IntroductionAging is related to decrease in taste perception. As appetite is considered crucial for maintenance of proper nutritional status of older adults, its decrease during aging raises questions about its relation to gustatory functions and further prevention possibilities. Aim of the studyThe aim was to assess the characteristics and eating behaviors of the patients who reported a self-perceived reduction in taste perception in the context of appetite. Material and methodsThis semi-qualitative study was conducted between November 2021 and March 2022 in the Department of Internal Medicine and Geriatrics of the University Hospital in Krakow. Patients were assessed using an original appetite assessment scale, which allowed for an in-depth interview on areas related to the decline in gustatory function. Additionally, nutritional assessment was performed using Mini Nutritional Assessment and Council on Nutrition Appetite Questionnaire (CNAQ) and anthropometric measurements. ResultsThe most common characteristics of patients with gustatory dysfunction were early satiety, decreased appetite in the three months prior to the study and polypharmacy. A significant difference was observed in the CNAQ scores between the group of patients with and without gustatory dysfunction. ConclusionCareful identification of patients presenting with gustatory dysfunction can provide an important cue for an individualised approach aimed at preventing malnutrition. In our work, we suggest the areas that can be addressed during a nutritional interview to enable the selection of an optimal approach.

Assessment of olfactory and gustatory functions in COVID-19 patients

BackgroundOlfactory and gustatory disorders are common problems encountered during the COVID-19 pandemic with a significant impact on the patient’s quality of life: The aim of this study was to assess the olfactory and gustatory functions in COVID-19 patients with correlation between them and clinical and laboratory markers. This was a cross-sectional study conducted on 63 subjects recruited from the COVID-19 clinics at Police Authority and Menoufia University hospitals. The patients were assessed using history taking, anterior rhinoscopy, endoscopic examination, computed tomography, and polymerase chain reaction (PCR) test. Olfactory functions were assessed using the alcohol threshold test. Gustatory functions were assessed using the three-drop method. The olfactory and gustatory functions were correlated with age, gender, and laboratory parameters. Also, the recovery of smell and taste disorders was correlated with our assessed laboratory markers.ResultsThe prevalence of olfactory dysfunction among study participants was 41 patients (65%) of the participants including 12 patients (19.1%) having mild hyposmia, 10 patients (15.8%) having moderate hyposmia, 9 patients (14.3%) having severe hyposmia, and 10 patients (15.8%) having complete anosmia. The prevalence of gustatory dysfunction among study participants was 24 patients (38.1%). Age, gender, and laboratory parameters did not show any statistically significant difference between those who experienced olfactory dysfunction or gustatory dysfunction and those who did not. However, there was a significant positive correlation between the total leucocytic count, serum level of CRP, and serum level of D-dimer and the degree of olfactory dysfunction (0.049, 0.03, and 0.02, respectively). There was a nonsignificant correlation between recovery of olfactory and gustatory dysfunction and laboratory markers.ConclusionOlfactory and gustatory dysfunction are established clinical presentations among COVID-19-positive patients. The laboratory markers had no correlation with the incidence of these dysfunctions or their recovery. However, TLC, serum CRP, and serum D-dimer had a significant positive correlation with the severity of olfactory dysfunction.

Longitudinal follow-up of taste function and trigeminal perception in COVID-19 patients with olfactory dysfunction – The COVORTS study

Longitudinal follow-up of taste function and trigeminal perception in COVID-19 patients with olfactory dysfunction – The COVORTS study

Preliminary observations of the gustatory function of sensilla on antennae of the female Spodoptera littoralis (Lepidoptera: Noctuidae): from single compounds to complex natural stimuli

Preliminary observations of the gustatory function of sensilla on antennae of the female Spodoptera littoralis (Lepidoptera: Noctuidae): from single compounds to complex natural stimuli

Home screening of taste and oral trigeminal function: a feasibility study

Purposegustatory ability is a marker of health not routinely tested in the medical practice. The current study wants to assess whether taste strips can be useful to monitor taste function from home.Methodswe performed simple sensory tests in lab setting vs. unassisted testing at home, and compared the results with self-reports ability to taste and smell. Using paper strips impregnated with sweet, bitter, salty, or sour tastants, and with two trigeminal stimuli (capsaicin, tannins) in high and low concentrations, we assessed gustatory and trigeminal function in 74 participants (47 women) in the lab, where paper strips were administered by an experimenter, and in 77 participants (59 women) at home, where they self-administered the test.Resultswe found that high (but not low) concentration taste strips are correctly identified by vast majority of participants. On average, taste identification, intensity and pleasantness scores did not differ for the 8 taste strips, while identification of capsaicin was significantly better in the lab. Taste identification scores correlated with intensity ratings in both settings (r = 0.56, in the lab, r = 0.48, at home, p < 0.005). Self-rated taste ability correlated with self-rated smell ability (r = 0.68, and r = 0.39, p ≤ 0.005), but not with scores in the strips test.Conclusionhome testing with impregnated taste strips is feasible, and can be used for telemedical purposes.

Incidence and prognosis of olfactory and gustatory dysfunctions related to SARS‐CoV‐2 Omicron strain infection in mainland China: A national multicenter survey of 35,566 individuals

AbstractObjectiveThis cross‐sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID‐19 in mainland China.MethodsThis study was conducted by 45 tertiary Grade‐A hospitals in mainland China. Online and offline questionnaire data were obtained from patients infected with COVID‐19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders.ResultsComplete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self‐reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms.ConclusionsThe incidence of dysosmia and dysgeusia following infection with the SARS‐CoV‐2 virus is high in mainland China. Incidence and prognosis are influenced by several factors, including sex, SARS‐CoV‐2 vaccination, history of head‐facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.

Relationship between olfactory and gustatory functions: The Iwaki health promotion project 2019

ObjectiveOlfactory and gustatory functions are important sensory aspects in humans. Although they are believed to influence each other, their interrelationship is not well understood. In this study, we aimed to investigate the relationship between the olfactory and gustatory functions based on the results of a large-scale epidemiological study (Iwaki Health Promotion Project) of the general local population. MethodsWe analyzed 565 participants who underwent taste and olfactory tests in the 2019 Iwaki Project. Gustatory function was tested for four taste qualities (sweet, sour, salty, and bitter) using whole-mouth taste tests. Olfactory function was tested using the University of Pennsylvania Smell Identification Test modified for Japanese (UPSIT-J). We evaluated sex-related differences between olfactory and gustatory functions and the effects of various factors on olfactory identification using multivariate analysis. Furthermore, we compared the percentage of accurate UPSIT-J responses between the normal and hypogeusia groups. We also analyzed the effects of taste and olfactory functions on eating. ResultsOlfactory and gustatory functions were lower in men than in women. Among the four taste qualities, salty taste was the most closely associated with olfactory identification ability, with lower olfactory scores of salty taste in the hypogeusia group than in the normal group. Moreover, the hyposmia group had higher daily salt intake than the normal olfaction group in women. ConclusionThese results suggest that olfactory identification tests may be useful in predicting elevated salt cognitive thresholds, leading to a reduction in salt intake, which may contribute to hypertension prevention.

Olfactory and gustatory functions, appetite, and nutritional status in Alzheimer's disease in a care facility

Olfactory and gustatory functions, appetite, and nutritional status in Alzheimer's disease in a care facility