Altered smell and taste: Anosmia, parosmia and the impact of long Covid-19.

BACKGROUND: Qualitative olfactory (smell) dysfunctions are a common side effect of post-viral illness and known to impact quality of life and health status. Evidence is emerging that taste and smell loss are common symptoms of Covid-19 that may emerge and persist long after initial infection. The aim of the present study was to document the impact of post Covid-19 alterations to taste and smell. METHODS: We conducted exploratory thematic analysis of user-generated text from 9000 users of the AbScent Covid-19 Smell and Taste Loss moderated Facebook support group from March 24 to 30th September 2020. RESULTS: Participants reported difficulty explaining and managing an altered sense of taste and smell; a lack of interpersonal and professional explanation or support; altered eating; appetite loss, weight change; loss of pleasure in food, eating and social engagement; altered intimacy and an altered relationship to self and others. CONCLUSIONS: Our findings suggest altered taste and smell with Covid-19 may lead to severe disruption to daily living that impacts on psychological well-being, physical health, relationships and sense of self. More specifically, participants reported impacts that related to reduced desire and ability to eat and prepare food; weight gain, weight loss and nutritional insufficiency; emotional wellbeing; professional practice; intimacy and social bonding; and the disruption of people's sense of reality and themselves. Our findings should inform further research and suggest areas for the training, assessment and treatment practices of health care professionals working with long Covid.

Quality of life and safety impact of COVID-19 associated smell and taste disturbances.

OBJECTIVE: The association between COVID-19 and chemosensory loss has garnered substantial attention, however to date little is known about the real-life consequences of impairment in this unique patient population. The aim of this study is to evaluate the quality of life (QOL) and personal safety deficits experienced by patients with COVID-19 infection. STUDY DESIGN: Prospective, longitudinal questionnaires. SETTING: National survey. METHODS: A longitudinal web-based nationwide survey of adults with COVID-19 and/or a sudden change in smell and taste was launched April 10, 2020. Previously published questions on chemosensory-related QOL and safety events were asked at the 6-month follow-up survey. RESULTS: As of February 10, 2021, 480 eligible respondents took the 6-month questionnaire, of whom 322 were COVID-19 positive. Impact on QOL was substantial with 96% of subjects reporting at least one of the defined deficits, and over 75% reporting at least 3 of these. "Reduced enjoyment of food" was the most common complaint (87%), while 43% of subjects self-reported depression. The prevalence of safety-related issues was common in this population, with over 57% reporting at least one, and 36% reporting 2 or more events. Of the events asked, the inability to smell smoke that others could perceive was the most common at 45%. CONCLUSIONS: COVID-19 associated chemosensory losses have a real and substantial impact on both quality of life and safety, beyond mere inconvenience. The high prevalence of these issues despite a relatively short period of olfactory deficit should alert clinicians to the serious risks to an already vulnerable patient population.

Differences in taste and smell perception between type 2 diabetes mellitus patients and healthy controls.

BACKGROUND AND AIMS: The senses of taste and smell are essential determinants of food choice, which in turn may contribute to the development of chronic diseases, including diabetes. Although past studies have evaluated the relationship between type 2 diabetes mellitus (DM2) and senses disorders, this relationship remains controversial. In this study, we evaluated taste and smell perception in DM2 patients and healthy controls (HC). Moreover, we analyzed the association of chemosensory impairments with anthropometric and clinical outcomes (e.g. Body Mass Index (BMI), Fasting blood glucose (FBG), drugs, cardiovascular diseases (CVD), and hypertension) in DM2 patients. METHODS AND RESULTS: The study included 94 DM2 patients and 244 HC. Taste recognition for 6-n-propylthiouracil (PROP), quinine, citric acid, sucrose, and sodium chloride (NaCl) compounds was assessed using a filter paper method, while smell recognition of 12 odorants was performed using a Sniffin' sticks test. We found that a higher percentage of DM2 patients showed identification impairment in salt taste (22% vs. 5%, p-value<0.0009) and smell recognition (55% vs. 27%, p-value = 0.03) compared to HC. We also observed that 65% of hypertensive DM2 subjects presented smell identification impairment compared to 18% of non-hypertensive patients (p-value = 0.019). Finally, patients with impairments in both taste and smell showed elevated FBG compared to patients without impairment (149.6 vs.124.3 mg/dL, p-value = 0.04). CONCLUSION: The prevalence of taste and smell identification impairments was higher in DM2 patients compared to HC, and a possible relationship with glycemic levels emerged.

Mood, Anxiety and Olfactory Dysfunction in COVID-19: Evidence of Central Nervous System Involvement?

OBJECTIVE: The objective of this study was to determine the burden of depressed mood and anxiety in COVID-19, and associated disease characteristics. MATERIALS AND METHODS: This is a prospective, cross-sectional study of 114 COVID-19 positive patients diagnosed using RT-PCR-based testing over a 6-week period. The two-item Patient Health Questionnaire (PHQ-2) and the two-item Generalized Anxiety Disorder questionnaire (GAD-2) were used to measure depressed mood and anxiety level, respectively, at enrollment and for participants' baseline, pre-COVID-19 state. Severity of smell loss, loss of taste, nasal obstruction, rhinorrhea/mucus production, fever, cough, and shortness of breath (SOB) during COVID-19 were assessed. RESULTS: PHQ-2 and GAD-2 significantly (P < .001) increased from baseline to enrollment. PHQ-2 was associated with smell loss (adjusted incidence rate ratio [aIRR] = 1.40, 95% CI, 1.10-1.78, P = .006), age (aIRR = 1.02, 95% CI, 1.01-1.04, P = .006), and baseline PHQ-2 score (aIRR = 1.39, 95% CI, 1.09-1.76, P = .007). GAD-2 score was associated with smell loss (aIRR = 1.29, 95% CI, 1.02-1.62, P = .035), age (aIRR = 1.02, 95% CI, 1.01-1.04, P = .025) and baseline GAD-2 score (aIRR = 1.55, 95% CI, 1.24-1.93, P < .001). Loss of taste also exhibited similar associations with PHQ-2 and GAD-2. PHQ-2 and GAD-2 scores were not associated with severities of any other symptoms during the COVID-19 course. CONCLUSIONS: Despite the occurrence of symptoms-such as SOB-associated with severe manifestations of COVID-19, only the severities of smell and taste loss were associated with depressed mood and anxiety. These results may raise the novel possibility of emotional disturbance as a CNS manifestation of COVID-19 given trans-olfactory tract penetration of the central nervous system (CNS) by coronaviruses. LEVEL OF EVIDENCE: 3 Laryngoscope, 130:2520-2525, 2020.

Psychophysical testing of smell and taste function.

The senses of smell and taste are largely underappreciated by laypersons and medical professionals alike. Unlike vision, hearing, balance, and touch, they are rarely evaluated quantitatively in the clinic, even though hundreds of thousands of persons seek medical help annually for disorders of these senses. Chemosensory disorders impact quality of life, including the flavor of foods and beverages, and compromise the ability to detect such environmental hazards as fires, leaking natural gas, and spoiled foodstuffs. Moreover, olfactory dysfunction can be a harbinger for Alzheimer's and other neurodegenerative diseases, and is known to triple the likelihood of mortality in older persons over the course of 4 or 5 years. Without accurate testing, one cannot establish the veracity of a patient's complaint, the probability of malingering, the impact of treatments, and whether the degree of dysfunction is normal relative to a patient's age and sex. This chapter provides basic information as to how to measure both the senses of smell and taste, as well as normative data for several clinical smell and taste tests.

Hemidysgeusia, phantosmia and respiratory arrest: a case of CLIPPERS.

A 56-year-old man presented with a relapse of likely chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) after a reduction of steroid dose. MRI demonstrated new perivascular FLuid-Attenuated Inversion Recovery (FLAIR) signal hyperintensity involving the dorsal pontomedullary junction and progressing inferiorly into the dorsal medulla oblongata. His admission to hospital was complicated by a respiratory arrest.

Taste changes in amyotrophic lateral sclerosis and effects on quality of life.

The primary aim of the study is to evaluate possible taste changes in a cohort of amyotrophic lateral sclerosis patients (pALS) with dysphagia, focusing on eventual psychological and quality of life (QoL) implications. The second aim is to evaluate the changes of QoL following the use of a specific device that provides food flavour. Thirty-two ALS patients were recruited and divided into two groups: subjects feeding only through enteral tube (ET) and subjects still eating by oral way (OW). A specific set of questionnaires was selected and adapted to investigate possible changes of taste and the impact on psychological status and QoL. Moreover, a specific device that provides food flavours in a safety manner was applied to all patients. We found a perceived reduction of taste in ALS patients, in particular in the ET group. All patients showed a strong interest in the preservation of taste, and its loss negatively related to their QoL. The use of the flavour device improved the perceived QoL showing no side effects, even in the ET group. For the first time, our study revealed changes in taste perception in a cohort of ALS patients and the negative consequences that these changes have on psychological status and QoL. Furthermore, the positive effects of the device used to provide flavours suggest a possible rehabilitative effect, which should be better evaluated and confirmed in further studies.

Taste changes as a metaphor for biographical disruption: A qualitative study in patients undergoing haematopoietic stem cell transplantation.

PURPOSE: and objective: The treatment side effects of patients undergoing haematopoietic stem cell transplantation can cause various eating difficulties. The objective of this study was to explore the significance of eating experiences and taste changes from the perspective of patients undergoing haematopoietic stem cell transplantation. METHOD: This was a qualitative, exploratory study based on semi-structured interviews applied during hospitalisation for haematopoietic stem cell transplantation. Thematic content analysis and the biographical disruption concept were used as theoretical references to explore the results. RESULTS: Twenty patients were studied. The overarching theme identified from the results was deconstruction of the taste reference resulting from sensory taste change, loss of eating references and changes to the hedonic relationship with food caused by the treatment. In addition to this deconstruction, participants described the reformulation of eating habits as a way of coping with the disease, which affected the eating experience and motivated the dietary strategies adopted. CONCLUSIONS: Taste changes during haematopoietic stem cell transplantation are related to both biological issues and metaphysical aspects. This study raises the meaning of loss of sensory references and their symbolic aspects. These results were important to expand our view to include other aspects that can contribute to improving the care given to these individuals.

A longitudinal study of altered taste and smell perception and change in blood pressure.

BACKGROUND AND AIMS: Previous studies suggest that olfactory receptors, which mediate smell chemosensation, are located in the kidney and involved in blood pressure regulation. Mammalian epithelial sodium channels located in taste receptor cells are also found to participate in blood pressure regulation. However, there is currently no human study that has examined the association between taste and smell function and blood pressure. We thus conducted a longitudinal study to examine whether participants with altered taste and smell perception had larger increases in blood pressure compared with those without altered perception in a community-based cohort. METHODS AND RESULTS: The study included 5190 Chinese adults (4058 men and 1132 women) who were normotensive at baseline. Taste and smell perception were assessed via questionnaire in 2012 (baseline). Blood pressure was measured in 2012 and 2014 to determine relative change in blood pressure. Mean differences of 2-year blood pressure change and 95% confidence intervals (CIs) across four categories of taste and smell perception were calculated after adjusting for known risk factors for hypertension. After adjusting for potential confounders, individuals with altered taste and smell perception had larger increases in systolic blood pressure (adjusted mean difference = 5.1 mmHg, 95% CI: 0.1-10.0, p-value: 0.04) and mean arterial pressure (adjusted mean difference = 3.8 mmHg, 95% CI: 0.4-7.1, p-value: 0.03) after two years of follow-up compared with those having neither altered taste nor altered smell perception. No significant association was observed in individuals with altered taste or smell perception only. CONCLUSION: Our results suggest an association between chemosensory function and blood pressure.

Insight in taste alterations during treatment with protein kinase inhibitors.

The role of Protein Kinase Inhibitors (PKI) in the treatment of various types of cancer is increasingly prominent. Their clinical application is accompanied by the development of side effects, among which patient-reported taste alterations. These alterations are missed frequently, but impair nutritional intake, are associated with weight loss and often result in significant morbidity, especially in the context of chronic administration. Accurate reporting of taste alterations is hampered by lack of modules for symptom objectification and inadequate understanding on the underlying mechanisms. In this review we initially describe the physiology of taste and smell and the mechanism of action of PKIs. We proceed to summarize taste related side effects as reported in major clinical trials and describe possible causal factors. Lastly, an in-depth analysis is given on potential molecular pathways responsible for the PKI-induced taste alterations. Objectification of patient-reported symptoms and universal reporting, along with a better understanding of the underlying mechanisms, will lead to early recognition and optimized treatment, ultimately improving patient adherence and quality of life.

Self-perceived taste disturbance: a 20-year prospective study of a Swedish 1942 birth cohort.

OBJECTIVES: The aim of this study was to assess the impact of dental care factors, general health factors and socio-economic factors on perceived taste disturbance (PTD) over time and to assess the stability of or change in PTD in a panel of individuals as they progressed from middle age (50 years) to early old age (70 years). MATERIALS AND METHODS: Data collection was conducted from a cohort study beginning in 1992, when the participants were 50 years old, and again 5, 10, 15 and 20 years later. Stability and change in PTD were described using cross-tabulation. Perceived taste disturbance over the 20-year survey period was modelled using the generalised estimating equation (GEE). RESULTS: The prevalence of PTD during a 5-year period found in this study ranged from 2.4 to 2.9%, the latter in individuals between 60 and 70 years of age. Women generally had PTD more often than men. The longitudinal analysis showed that problems with bad breath (OR = 3.6), blisters (OR = 3.4), burning mouth (OR = 3.4) and self-perceived health (OR = 2.7) were the most important factors explaining PTD. CONCLUSIONS: This study showed that PTD does not increase between 50 and 70 years of age in ordinary community-living individuals. There were no long-term impacts on PTD over time from socio-economic factors, and over time, there were a limited number of factors contributing to the effect. Bad breath, blisters, burning mouth and self-perceived health are important factors for the dentist to discuss with the patient in the case of PTD.

Taste disturbance after stapes surgery: an evaluation of frequency, severity, duration, and quality-of-life.

CONCLUSION: The incidence of taste disturbance after stapes surgery is high (61.9%), whereas the majority (94.8%) recovers within 1 year. More severe surgical nerve trauma caused more disturbance, implying that the nerve should be handled carefully during surgery. OBJECTIVES: Patients operated on for otosclerosis seem more often to complain about post-operative taste disturbance than those operated on for chronic otitis media, although the chorda tympani nerve more seldom becomes maltreated in stapedotomy. These observations seem paradoxical. It is unclear to what extent a post-operative taste disturbance affects the quality-of-life. This study aims to shed light on the occurrence of post-operative taste disturbances, on possible prognostic factors, and to what extent post-operative taste disturbance impairs the quality-of-life. METHODS: One hundred and thirty-four adults undergoing primary stapedotomy were included. Questionnaires on taste disturbance and quality-of-life (SF-36) were answered before and after surgery, until 1 year post-operatively. RESULTS: Eighty-three (61.9%) study persons reported post-operative taste disturbance. Seven (5.2%) reported persisting disturbance at 1 year. Surgically more traumatized chorda tympani nerves correlated with more severe taste disturbance post-operatively than less traumatized. Taste disturbance at 1 year post-operatively correlate with a decrease of the physical function domain in the SF-36.

Food acceptance and neophobia in children with phenylketonuria: a prospective controlled study.

BACKGROUND: In phenylketonuria (PKU), little is known about the effect of bitter-tasting phenylalanine-free l-amino acid exposure on taste preference development. The present prospective study aimed to determine the flavour preferences of children with PKU versus healthy control children. METHODS: Thirty-five children with PKU and 35 age/gender-matched controls, aged 4-13 years, tasted 10 blinded puree foods in random order. They were rated using a seven-point pictorial hedonic scale (super yummy to super yucky) and ranked in preferential order. Caregivers completed a neophobia and food frequency questionnaire on behalf of their children. RESULTS: Both PKU and control groups rated sweet foods higher than savoury, bitter and sour foods. However, control children ranked fruits as a group higher than PKU children (mean 3.7 versus 4.6; P = 0.03), whereas PKU children ranked vegetables as a group higher than controls (mean 5.6 versus 6.3; P = 0.05). Children with PKU had more neophobia and were untrusting/fearful of new foods. CONCLUSIONS: Although there was some evidence to suggest that children with PKU aged ≥4 years prefer savoury foods (vegetables) more than control children, they did not prefer bitter-tasting foods, and so early and persistent administration of bitter-tasting l-amino acids was not associated with apparent taste imprinting. Neophobia appears to play significant part in food refusal in PKU, perhaps more so than taste preferences.

Individual oral symptoms in burning mouth syndrome may be associated differentially with depression and anxiety.

BACKGROUND: Burning mouth syndrome (BMS) is an idiopathic disease characterized by the feeling of burning in the oral cavity. Ten per cent of patients presenting to oral medicine clinics have BMS. Anxiety and depression are common co-morbidities in BMS, but it is not known if they are associated with specific BMS symptoms. OBJECTIVE: In an exploratory analysis, this study examined the association of generalized anxiety and depression with individual BMS symptoms. METHODS: Forty-one patients were recruited from a dental outpatient clinic (30 with BMS and 11 with other oral conditions), evaluating specific BMS symptoms and their intensity. Anxiety and depression symptoms were assessed using a standardized measure (Clinical Interview Schedule-Revised). RESULTS: Taste change (p = 0.007), fear of serious illness (p = 0.011), metallic taste (p = 0.018) and sensation of a film on the gums (p = 0.047) were associated with an excess of psychiatric symptoms. More specifically, metallic taste (coefficient = 0.497, 95% CI = 0.149-0.845; p = 0.006) and sensation of film on gums (coefficient = 0.625, 95% CI = 0.148-1.103; p = 0.012) were associated significantly with higher scores for depressive symptoms; taste change (coefficient = 0.269, 95% CI = 0.077-0.461; p = 0.007), bad breath (coefficient = 0.273, 95% CI = 0.065-0.482; p = 0.012) and fear of serious illness (coefficient = 0.242, 95% CI = 0.036-0.448; p = 0.023) were associated with higher anxiety scores. CONCLUSION: Specific BMS symptoms are associated differentially with generalized anxiety and depression. Dental practitioners should ascertain which BMS symptoms are predominant and be mindful of the association of certain symptoms with anxiety or depression and, where necessary, consider medical consultation.

Residual deficits in quality of life one year after intensity-modulated radiotherapy for patients with locally advanced head and neck cancer: Results of a prospective study.

PURPOSE: Patients with locally advanced head and neck cancer (LAHNC) undergo life-changing treatments that can seriously affect quality of life (QoL). This prospective study examined the key QoL domains during the first year after intensity-modulated radiotherapy (IMRT) and identified predictors of these changes in order to improve patient outcomes. PATIENTS AND METHODS: A consecutive series of patients with LAHNC completed the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core module (QLQ-C30) and the HNC-specific QLQ-HN35 before (t0) and at the end (t1) of definitive or adjuvant IMRT, then at 6-8 weeks (t2), 6 months (t3), and 1 year (t4) after IMRT. RESULTS: Patients (n = 111) completing questionnaires at all five time points were included (baseline response rate: 99%; dropout rate between t0 and t4: 5%). QoL deteriorated in all domains during IMRT and improved slowly during the first year thereafter. Many domains recovered to baseline values after 1 year but problems with smelling and tasting, dry mouth, and sticky saliva remained issues at this time. Increases in problems with sticky saliva were greater after 1 year in patients with definitive versus adjuvant IMRT (F = 3.5, P = 0.05). CONCLUSION: QoL in patients with LAHNC receiving IMRT takes approximately 1 year to return to baseline; some domains remain compromised after 1 year. Although IMRT aims to maintain function and QoL, patients experience long-term dry mouth and sticky saliva, particularly following definitive IMRT. Patients should be counseled at the start of therapy to reduce disappointment with the pace of recovery.

Impact of combined sensory impairments on health-related quality of life.

PURPOSE: To analyse the impact of single/combined sensory impairment on health-related quality of life (HRQOL). METHODS: Data from 1102 participants (mean age = 51.4 years) of the Dortmund Health Study were analysed. HRQOL was assessed by the Short Form 36 Health Survey (SF-36). Sensory impairment was measured with validated tests. Each impairment variable was coded into four categories (no impairment, mild, moderate, and severe impairment). Data were analysed with general linear models adjusted for possible confounders. The reference category was the group of no sensory impairment. RESULTS: Sensory impairments did not influence the mental component score (MCS). Severe auditory impairment (-3.7, 95 % CI -6.3, -1.2) and olfactory impairment (-3.3, 95 % CI -5.6, -1.1) were related to a reduction in the physical component score (PCS). Auditory plus visual and gustatory plus visual impairments had a stronger effect on PCS than the respective impairments alone. For most of the other impairment combinations, additive effects were observed. CONCLUSIONS: Sensory impairments reduced self-reported physical but not mental health scores. Combined sensory impairment worsened the impact of single sensory impairment on health.

Characteristics of chemosensory disorders--results from a survey.

This survey was undertaken to investigate the nature of chemosensory dysfunction in relation to the underlying cause, severity, and course of the disease and to elucidate their clinical significance. A total of 269 patients (116 men and 149 women) with chemosensory disorders participated in the survey. Approximately 89 % had olfactory loss, either alone or in combination with taste loss and 2 % had gustatory loss alone; 7.4 % had chemosensory distortions. Dysosmia was significantly higher in those on more than four medicines per day (p < 0.02). Most patients (51.6 %) reported sudden onset of symptoms. Self-reported etiologies included: flu/infection (39.4 %), medication intake (13 %), sinusitis (12 %), operation (10.7 %), head-trauma (9.3 %), and not-specified (12.7 %). The most frequent complaint was diminished pleasure from eating followed by a decrease in general quality of life (QoL). Patients with gradual onset of symptoms or long-standing disease complained the least (p < 0.005). Of all etiologies, patients with SND complained the most (p < 0.04). Overall, 18.6 % ate more and 7.3 % ate less, 7.5 % changed their food preferences, and 19 % reported weight gain and 15.8 % weight loss. Haptic feedback was considered more important than visual appeal and acoustic feedback of food. Older patients however valued visual appeal more. When asked directly, 63 % reported having experienced household-mishaps, 58.1 % problems with social communication, 56.8 % reported having changed their sexual behavior and 35.9 % suffered depression. 60.4 % did not cope well with the changes in their lives. Women reported more problems than men, particularly relating to interpersonal communication (64.5 vs. 57.6 %) and mood (47.9 vs. 40.9 %). Women also had more frequent spontaneous recollections of smells (p < 0.02). Chemosensory disorders have a significant impact on QoL. Reduced pleasure from eating is the predominant complaint of patients seeking medical attention. The steeper the onset of symptoms, the worse the ability to cope with changes in daily life. Older patients value the visual appeal, whereas younger patients value the haptic feedback of foods.

Discomfort associated with fixed orthodontic appliances: determinant factors and influence on quality of life.

OBJECTIVE: To investigate the determinant factors of discomfort attributed to the use of fixed orthodontic appliance and the effect on the quality of life of adolescents. MATERIAL AND METHODS: Two hundred and seventy-two individuals aged between 9 and 18 years old, enrolled in public and private schools and undergoing orthodontic treatment with fixed appliance participated in this cross-sectional study. The participants were randomly selected from a sample comprising 62,496 individuals of the same age group. Data was collected by means of questionnaires and an interview. Discomfort intensity and bio-psychosocial variables were assessed using the Oral Impact on Daily Performance questionnaire. Self-esteem was determined using the Global Negative Self-Evaluation questionnaire. Statistical analysis involved the chi-square test and both simple and multiple Poisson regression analyses. RESULTS: Although most individuals did not present discomfort, there was a prevalence of 15.9% of impact on individuals' daily life exclusively due to the use of fixed orthodontic appliance. Age [PR: 3.2 (95% CI: 1.2-8.5)], speech impairment [PR: 2.2 (95% CI: 1.1-4.6)], poor oral hygiene [PR: 2.4 (95% CI: 1.2-4.8)] and tooth mobility [PR: 3.9 (95% CI: 1.8-8.1)] remained independently associated with a greater prevalence of discomfort (P ≤ 0.05). CONCLUSIONS: Discomfort associated with the use of fixed orthodontic appliances exerted a negative influence on the quality of life of the adolescents comprising the present study. The determinants of this association were age, poor oral hygiene, speech impairment and tooth mobility.