Measuring taste impairment in epidemiologic studies: the Beaver Dam Offspring Study

Comparison of Bitterness Intensity between Prednisolone and Quinine in a Human Sensory Test Indicated Individual Differences in Bitter-Taste Perception

Prednisolone is a frequently prescribed steroid with a bitter, unpalatable taste that can result in treatment refusal. Oral suspensions or powder dosage forms are often prescribed, particularly to pediatric patients, as they improve swallowability and ease of dose adjustment. Consequently, the bitterness of prednisolone is more apparent in these dosage forms. Few studies have investigated prednisolone's bitterness. Thus, in this study, 50 adults evaluated the bitterness of prednisolone using the generalized Labeled Magnitude Scale (gLMS), in comparison with quinine, a standard bitter substance. Overall, prednisolone-saturated solution demonstrated the same extent (mean gLMS score: 46.8) of bitterness as 1 mM quinine solution (mean gLMS score: 40.1). Additionally, large individual differences were observed in the perception of the bitterness of prednisolone and quinine. Perceived flavors of some drugs are reportedly associated with bitter-taste receptor (TAS2Rs) polymorphisms. Therefore, we investigated the relationship between subjects' genetic polymorphisms of TAS2R19, 38, and 46, and their sensitivity to bitterness. Although a relationship between TAS2R19 polymorphisms and the perception of quinine bitterness was observed, no significant relationship was found between the perceived bitterness of prednisolone and the investigated genes. Ultimately, the results show that despite individual differences among subjects, the cause of prednisolone's strong bitterness is yet to be elucidated.

The association between olfactory and gustatory dysfunction and chronic kidney disease

BACKGROUND

Olfactory and gustatory changes may contribute to poor appetite and food aversion in chronic kidney disease (CKD), though the prevalence of olfactory and gustatory dysfunction is not known in the CKD population.

METHODS

We conducted a cross-sectional study among 3527 US adults aged ≥40 years old in the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2014. We measured the prevalence of olfactory and gustatory dysfunction among patients with CKD defined as eGFR < 60 ml/min/1.73m² using the "scratch and sniff" NHANES Pocket Smell Test and quinine whole-mouth test. We also examined the association between CKD and olfactory/gustatory dysfunction, and nutritional markers.

RESULTS

The prevalence of olfactory dysfunction was 30% among CKD and 15% among non-CKD (p < 0.001). The prevalence of gustatory dysfunction was 13% among CKD and 17% among non-CKD (p = 0.10). After adjusting for confounders, CKD was significantly associated with olfactory dysfunction (OR = 1.47, 95% CI [1.07, 2.01]; p = 0.02) but not gustatory dysfunction (OR = 1.76, 95%CI [0.99, 3.11]; p = 0.05). Among the CKD population, the odds of olfactory dysfunction was 72% higher for every 10 kg decrease in grip strength (OR = 1.72, 95% CI [1.39, 2.13]; adjusted p = 0.005).

CONCLUSION

CKD was associated with higher odds of olfactory but not gustatory dysfunction. Olfactory dysfunction was associated with lower grip strength among those with CKD. Screening and early intervening on olfactory dysfunction among CKD may preserve muscle strength and improve nutritional status in this vulnerable population.

Homogeneity of thermal tasters and implications for mechanisms and classification

Thermal tasting, an important type of individual variation in orosensation, is a phenomenon by which some individuals perceive thermally-induced taste sensations simply by having the tip of their tongue warmed or cooled. These individuals, known as thermal tasters, report a variety of thermally-elicited tastes (typically sweet, sour, salty, bitter, metallic) and the tastes reported can vary with the temperature regime used (warming or cooling) and location on the tongue tested. Importantly, when compared to thermal non-tasters, thermal tasters are more responsive to aqueous solutions of basic tastants and to beverages. The mechanism(s) underlying thermal tasting are not well understood and it is unknown if the increased orosensory responsiveness of thermal tasters is universal or if it is driven by a subgroup of thermal tasters. Thermal taste data from 12 previous studies was combined to obtain a large sample of thermal tasters (n = 254) who were divided into subgroups based on the type of thermally-elicited taste reported and the temperature regime/location at which it was experienced. Sweet thermal tasters (n = 77) were 9 times more likely than non-sweet thermal tasters (n = 177) to experience thermally-elicited sensations during lingual warming (p < 0.0001). Similarly, sour thermal tasters (n = 89) were 8 times more likely than non-sour thermal tasters (n = 165) to report thermally induced tastes during cooling (p<0.0001). However, no differences in orosensory responsiveness based on these or other subgroups were identified, suggesting that the heightened orosensory responsiveness of thermal tasters may be centrally-mediated. We discuss how these findings inform our understanding of the mechanism(s) underlying thermal taste and the identification of thermal taste subgroups, along with practical implications of methodological differences in determining thermal taste status.

Individual Variation in PROP Status, Fungiform Papillae Density, and Responsiveness to Taste Stimuli in a Large Population Sample

Despite considerable research investigating the role of 6-n-propylthiouracil bitterness perception and variation of fungiform papillae density in food perception, this relationship remains controversial as well as the association between the 2 phenotypes. Data from 1119 subjects (38.6% male; 18-60 years) enrolled in the Italian Taste project were analyzed. Responsiveness to the bitterness of 6-n-propylthiouracil was assessed on the general Labeled Magnitude Scale. Fungiform papillae density was determined from manual counting on digital images of the tongue. Solutions of tastes, astringent, and pungent sensations were prepared to be moderate/strong on a general Labeled Magnitude Scale. Four foods had tastants added to produce 4 variations in target sensations from weak to strong (pear juice: citric acid, sourness; chocolate pudding: sucrose, sweetness; bean purée: sodium chloride, saltiness; and tomato juice: capsaicin, pungency). Women gave ratings to 6-n-propylthiouracil and showed fungiform papillae density that was significantly higher than men. Both phenotype markers significantly decreased with age. No significant correlations were found between 6-n-propylthiouracil ratings and fungiform papillae density. Fungiform papillae density variation does not affect perceived intensity of solutions. Responsiveness to 6-n-propylthiouracil positively correlated to perceived intensity of most stimuli in solution. A significant effect of fungiform papillae density on perceived intensity of target sensation in foods was found in a few cases. Responsiveness to 6-n-propylthiouracil positively affected all taste intensities in subjects with low fungiform papillae density whereas there were no significant effects of 6-n-propylthiouracil in those with high fungiform papillae density. These data highlight a complex interplay between 6-n-propylthiouracil status and fungiform papillae density and the need of a critical reconsideration of their role in food perception and acceptability.

Prolonged Exposure to Monosodium Glutamate in Healthy Young Adults Decreases Perceived Umami Taste and Diminishes Appetite for Savory Foods

Background

Research suggests that increased consumption of sweet, salt, or fat is associated with diminished perceived taste intensity and shifted preferences for the respective stimulus. It is unknown whether a similar effect occurs with the consumption of umami.

Objective

The aim of the study was to investigate the influence of habitual exposure to umami stimuli on umami taste perception, hedonics, and satiety.

Methods

Fifty-eight healthy men (n = 16) and women (n = 42) participated in a parallel-group, randomized controlled study. The normal-weight [mean ± SD body mass index (kg/m2): 21.8 ± 2.2] group of young adults (mean ± SD age: 22.7 ± 6.2 y) consumed vegetable broth daily for 4 wk. The broth for the treatment group (n = 28) was supplemented with 3.8 g monosodium glutamate (MSG), whereas the control group (n = 30) consumed a sodium-matched broth without MSG. Perceived umami taste intensity and discrimination in MSG solutions; liking, wanting, and preference of a variety of umami-rich foods; satiation and satiety from an ad libitum meal; and anthropometric measures were evaluated at baseline and at week 4. General linear models assessed the effect of treatment on change from baseline for all outcomes and tested for effect modification of sex.

Results

Relative to controls, increased consumption of MSG for 4 wk diminished umami taste in women (8.4 units on generalized Labeled Magnitude Scale; 95% CI: -13.8, -3.1 units; P = 0.013). The desire for and intake of savory foods decreased after MSG treatment in both sexes with an ad libitum meal (desire: -7.7 units; 95% CI: -13.7, -1.7 units; P = 0.04; intake: -36 g; 95% CI: -91, 19 g; P = 0.04).

Conclusion

Our results highlight that a month-long diet high in umami stimuli attenuates perceived umami taste and appetite for savory foods in a young, healthy population. Our findings contribute to the understanding of food choice, a factor in the development and maintenance of obesity, as well as the etiology of protein-related health conditions such as osteoporosis and kidney disease. This study is registered at www.clinicaltrials.gov as NCT03010930.

Taste impairment in chronic rhinosinusitis

BACKGROUND

Though many patients with chronic rhinosinusitis (CRS) describe disturbances in smell and taste, there have been no studies specifically assessing taste impairment in CRS. This study sought to objectively assess taste dysfunction in CRS patients and determine whether taste impairment correlates with olfactory dysfunction. Additionally, this investigation sought to determine the impact of taste dysfunction on quality of life (QOL) in CRS and identify the clinical factors that influence taste.

METHODS

Sixty-eight CRS patients were prospectively enrolled and completed several QOL surveys in relation to taste, smell, overall sinus-specific QOL, and depression. Validated taste strips were used to determine gustatory dysfunction pertaining to sweet, sour, salty, and bitter. Olfactory testing was assessed using the Sniffin' Sticks Test while both Lund-Kennedy and Olfactory Cleft Endoscopy Scoring (OCES) systems were used for endoscopic evaluation.

RESULTS

The overall prevalence of dysgeusia was 28%, with scores significantly lower for sour compared to other subgroups. No correlation was observed between taste scores and objective olfactory metrics including olfaction tests and OCES. Taste scores were better in younger patients (r = 0.28, p = 0.02), female patients (p = 0.004), and never smokers compared to former smokers (p = 0.01). Taste scores did not correlate with patient-reported outcome measures or CRS disease severity metrics.

CONCLUSION

Taste dysfunction is a common complaint in CRS. This cohort shows prevalence of gustatory loss to be about 28% using ideal normative values. This dysfunction correlated with male gender, smoking history, and older age. Taste dysfunction did not correlate with measured olfactory outcomes.

New chemosensory component in the U.S. National Health and Nutrition Examination Survey (NHANES): first-year results for measured olfactory dysfunction

The U.S. NHANES included chemosensory assessments in the 2011-2014 protocol. We provide an overview of this protocol and 2012 olfactory exam findings. Of the 1818 NHANES participants aged ≥40 years, 1281 (70.5 %) completed the exam; non-participation mostly was due to time constraints. Health technicians administered an 8-item, forced-choice, odor identification task scored as normosmic (6-8 odors identified correctly) versus olfactory dysfunction, including hyposmic (4-5 correct) and anosmic/severe hyposmic (0-3 correct). Interviewers recorded self-reported smell alterations (during past year, since age 25, phantosmia), histories of sinonasal problems, xerostomia, dental extractions, head or facial trauma, and chemosensory-related treatment and changes in quality of life. Olfactory dysfunction was found in 12.4 % (13.3 million adults; 55 % males/45 % females) including 3.2 % anosmic/severe hyposmic (3.4 million; 74 % males/26 % females). Selected age-specific prevalences were 4.2 % (40-49 years), 12.7 % (60-69 years), and 39.4 % (80+ years). Among adults ≥70 years, misidentification rates for warning odors were 20.3 % for smoke and 31.3 % for natural gas. The highest sensitivity (correctly identifying dysfunction) and specificity (correctly identifying normosmia) of self-reported olfactory alteration was among anosmics/severe hyposmics (54.4 % and 78.1 %, respectively). In age- and sex-adjusted logistic regression analysis, risk factors of olfactory dysfunction were racial/ethnic minority, income-to-poverty ratio ≤ 1.1, education <high school, and heavy drinking. Moderate-to-vigorous physical activity reduced risk of impairment. Olfactory dysfunction is prevalent, particularly among older adults. Inexpensive, brief odor identification tests coupled with questions (smell problems past year, since age 25, phantosmia) could screen for marked dysfunction. Healthcare providers should be prepared to offer education on non-olfactory avoidance of hazardous events.

The Taste and Smell Protocol in the 2011-2014 US National Health and Nutrition Examination Survey (NHANES): Test-Retest Reliability and Validity Testing

INTRODUCTION

The US NHANES 2011-2014 protocol includes a taste and smell questionnaire (CSQ) in home-based interviews and brief assessments in mobile exam centers. We report the short- and longer-term test-retest reliability and validity of this protocol against broader chemosensory measures.

METHODS

A convenience sample of 73 adults (age=39.5±20.8 years) underwent the NHANES protocol at baseline, 2 weeks and 6 months. For taste, participants rated intensities of two tastants (1 M NaCl, 1 mM quinine) applied to the tongue tip and three tastants (1 M NaCl, 1 mM quinine, 0.32 M NaCl) sampled with the whole mouth. Smell function was assessed with a Pocket Smell Test™ (PST; eight-item odor identification test). The CSQ asked about chemosensory problems, distortions, and age-related changes. Broader baseline measurements were a 40-item olfactometer-generated identification task and additional whole-mouth taste intensities (1 M sucrose, 32 mM citric acid, 3.2 mM propylthiouracil).

RESULTS

Intraclass correlations (ICCs) for NHANES taste measures showed moderate-to-good agreement after 2 weeks and 6 months (ICCs 0.42-0.71). Whole-mouth quinine intensity was significantly correlated with other taste intensities, supporting its utility as a marker for overall taste functioning. Olfactory classification from PSTs agreed for 98.5 % of participants across 2 weeks (κ=0.85; 95 % CI 0.71-0.99) and had good correspondence with the olfactometer task. CSQ items showed good-to-excellent agreement over 6 months (ICCs 0.66-0.90).

CONCLUSIONS

These findings further support that the NHANES chemosensory protocol has moderate-to-good test-retest reliability when administered to healthy, educated adults. Despite being a brief procedure with limited measures, the NHANES taste and smell assessments provided good information when compared to broader measures of taste and smell function.

Denver Papillae Protocol for Objective Analysis of Fungiform Papillae

The goal of the Denver Papillae Protocol is to use a dichotomous key to define and prioritize the characteristics of fungiform papillae (FP) to ensure consistent scoring between scorers. This protocol builds off of a need that has arisen from the last two decades of taste research using FP as a proxy for taste pore density. FP density has historically been analyzed using Miller & Reedy’s 1990 characterizations of their morphology: round, stained lighter, large, and elevated. In this work, the authors forewarned that stricter definitions of FP morphology needed to be outlined. Despite this call to action, follow up literature has been scarce, with most studies continuing to cite Miller & Reedy’s original work. Consequently, FP density reports have been highly variable and, combined with small sample sizes, may contribute to the discrepant conclusions on the role of FP in taste sensitivity. The Genetics of Taste Lab explored this apparent inconsistency in counting and found that scorers were individually prioritizing the importance of these characteristics differently and had no guidance for when a papilla had some, but not all, of the reported qualities of FP. The result of this subjectivity is highly variable FP counts of the same tongue image. The Denver Papillae Protocol has been developed to remedy this consequence through use of a dichotomous key that further defines and prioritizes the importance of the characteristics put forth by Miller & Reedy. The proposed method could help create a standard way to quantify FP for researchers in the field of taste and nutritional studies.

The associations between 6-n-propylthiouracil (PROP) intensity and taste intensities differ by TAS2R38 haplotype

BACKGROUND/AIMS

The influence of TAS2R38 haplotype on the relationship between the perceived intensity of propylthiouracil (PROP) and the basic tastes of salt, sweet, sour, and bitter (quinine) was evaluated in the Beaver Dam Offspring Study.

METHODS

Genotyping was performed on 1,670 participants aged ≥45 years (mean age = 54.4; range = 45-84), and suprathreshold taste intensity was measured using filter paper disks and a general labeled magnitude scale (0-100).

RESULTS

Among those with taste intensity data and the PAV or AVI haplotype (n = 1,258), the mean perceived intensity of PROP was 37.3 (SD = 30.0), but it varied significantly (p < 0.0001) by diplotype (PAV/PAV = 60.1; PAV/AVI = 46.5; AVI/AVI = 14.4). PROP intensity was correlated with the basic taste intensities (salt: r = 0.22; sweet: r = 0.25; sour: r = 0.21; quinine bitterness: r = 0.38; p < 0.001 for all tastes); however, a significant effect modification of the PROP-taste intensity relationships by TAS2R38 diplotype was observed. There was a stronger association between PROP and each of the basic tastes in the PAV/PAV diplotype group than in the other groups.

CONCLUSIONS

Directly measuring the perceived intensity of the 4 tastes, rather than using PROP intensity as an indicator of taste responsiveness, is recommended for studies of taste perception.

The association of taste with change in adiposity-related health measures

The relationship between taste-intensity patterns and 5-year change in adiposity-related health measures was determined. Participants were members of the Beaver Dam Offspring Study, a study of the adult children of participants in the population-based Epidemiology of Hearing Loss Study. There were 1,918 participants (mean baseline age=48.8 years; range=22 to 84 years) with baseline taste (2005 to 2008) and follow-up (2010 to 2013) data. Outcomes included 5-year change in body mass index, waist circumference, blood pressure, non-high-density lipoprotein cholesterol, and glycosylated hemoglobin A1c, and hedonic ratings of specific foods. Cluster analysis with Ward's minimum variance method identified the following 5 patterns of the suprathreshold taste intensities of salt, sweet, sour, and bitter: salt and sweet intensities slightly above population averages, average sour and bitter intensities; salt, sour, and bitter intensities above population average, average sweet intensity; salt, sour, and bitter intensities above population average, sweet intensity substantially above average; all intensities below population averages; and all intensities close to population average. The General Linear Model procedure was used for testing cluster differences in the outcomes. With covariate adjustment, the group with all intensities close to population averages had a significantly lower average increase in body mass index compared with the group with above-average intensities for salt, sour, and bitter (+0.4 vs +0.9), and in glycosylated hemoglobin A1c compared with the group with above-average intensities for all tastes (+0.20% vs +0.34%). Clusters differed in the hedonics of foods representing sweetness and saltiness. The study's findings provide evidence that perceived taste intensity might be related to changes in adiposity-related health.

Factors related to fungiform papillae density: the beaver dam offspring study

The distribution of fungiform papillae density and associated factors were examined in the Beaver Dam Offspring Study. Data were from 2371 participants (mean age = 48.8 years, range = 21-84 years) with 1108 males and 1263 females. Fungiform papillae were highlighted with blue food coloring and the number of fungiform papillae within a standard 6-mm circle was counted. Whole mouth suprathreshold taste intensity was measured. The mean fungiform papillae density was 103.5 papillae/cm(2) (range = 0-212.2 papillae/cm(2)). For each 5-year increase in age, the mean fungiform papillae density was 2.8 papillae/cm(2) lower and the mean density for males was 10.2 papillae/cm(2) lower than for females. Smokers had significantly lower mean densities (former smokers: -5.1 papillae/cm(2); current smokers: -9.3 papillae/cm(2)) than nonsmokers, and heavy alcohol drinkers had a mean density that was 4.7 papillae/cm(2) lower than nonheavy drinkers. Solvent exposure was related to a significantly higher density (+6.8 papillae/cm(2)). The heritability estimate for fungiform papillae density was 40.2%. Propylthiouracil taster status, TAS2R38 haplotype, and perceived taste intensity were not related to density. In summary, wide variability in fungiform papillae density was observed and a number of related factors were found including the modifiable factors of smoking and alcohol consumption.

Taste intensity in the Beaver Dam Offspring Study

OBJECTIVES/HYPOTHESIS

To determine the distribution of the perceived intensity of salt, sweet, sour, and bitter in a large population and to investigate factors associated with perceived taste intensity.

STUDY DESIGN

Cross-sectional population.

METHODS

Subjects (n = 2,374; mean age, 48.8 years) were participants in the Beaver Dam Offspring Study examined during 2005 to 2008. Perceived taste intensity was measured using paper disks and a general labeled magnitude scale. Multiple linear regression was performed.

RESULTS

Mean intensity ratings were: salt = 27.2 (standard deviation [SD] = 18.5), sweet = 20.4 (SD = 15.0), sour = 35.7 (SD = 21.4), and bitter = 49.6 (SD = 23.3). Females and those with less than a college degree education rated tastes stronger. With adjustment for age, sex, and education, stronger perceived sour and bitter intensities were related to current smoking (sour: B = 2.8, 95% confidence interval [CI], 0.4 to 5.2; bitter: B = 2.8, 95% CI, 0.3 to 5.4) and lipid-lowering medications (sour: B = 5.1, 95% CI, 2.5 to 7.6; bitter: B = 3.2, 95% CI, 0.6 to 5.8). Alcohol consumption in the past year was related to weaker salt (B = -2.8, 95% CI, -5.3 to -0.3) and sweet intensity ratings (B = -2.3, 95% CI, -4.3 to -0.3), whereas olfactory impairment was associated with higher sweet ratings (B = 4.7, 95% CI, 1.4 to 7.9).

CONCLUSIONS

Perceived intensities were strongest for bitter and weakest for sweet. Sex and education were associated with each taste, whereas age did not demonstrate a consistent relationship. Associations with other factors differed by tastants, with current smoking and alcohol consumption being related to some tastes.

Reproducibility of the measurement of sweet taste preferences

Developing interventions to prevent and treat obesity are medical and public health imperatives. Taste is a major determinant of food intake and reliable methods to measure taste preferences need to be established. This study aimed to establish the short-term reproducibility of sweet taste preference measurements using 5-level sucrose concentrations in healthy adult volunteers. We defined sweet taste preference as the geometric mean of the preferred sucrose concentration determined from two series of two-alternative, forced-choice staircase procedures administered 10min apart on a single day. We repeated the same procedures at a second visit 3-7days later. Twenty-six adults (13 men and 13 women, age 33.2±12.2years) completed the measurements. The median number of pairs presented for each series was three (25th and 75th percentiles: 3, 4). The intraclass correlation coefficients between the measurements was 0.82 (95% confidence interval [CI]: 0.63-0.92) within a few days. This study showed high short-term reproducibility of a simple, 5-level procedure for measuring sweet taste preferences. This method may be useful for assessing sweet taste preferences and the risks resulting from those preferences.

Intensity of Salt Taste and Prevalence of Hypertension Are Not Related in the Beaver Dam Offspring Study

BACKGROUND: Standard clinical advice for the prevention and treatment of hypertension includes limitation of salt intake. Previous studies of the association between perception of salt taste and hypertension prevalence have not reported consistent results and have usually been conducted in small study populations. PURPOSE: To determine the cross-sectional relationship between intensity of salt taste, discretionary salt use, and hypertension. METHODS: Subjects (n=2371, mean age=48.8 years) were participants in the Beaver Dam Offspring Study (BOSS), an investigation of sensory loss and aging conducted in 2005-2008. Salt taste intensity was measured using a filter paper disk impregnated with 1.0 M sodium chloride and a general Labeled Magnitude Scale (gLMS). Hypertension was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg, or use of high blood pressure medication. RESULTS: Nearly 32% of the participants rated the salt disk as weak or having no taste while approximately 10% considered it to be very strong or stronger. The intensity was reported to be less strong by males (P < 0.001) and college graduates (P = 0.02) and was inversely associated with frequency of adding salt to foods (P = 0.02). There was no significant association between hypertension and the intensity of salt taste, before and after adjustment for covariates. Exclusion of subjects with a history of physician diagnosed hypertension did not appreciably alter these findings. CONCLUSIONS: The perception of salt taste was related to the frequency of discretionary salt use but not to hypertension status or mean blood pressure.

Carotid atherosclerosis and cognitive function in midlife: the Beaver Dam Offspring Study

BACKGROUND

Atherosclerosis may be associated with cognitive function; however the studies are few, especially among midlife adults.

METHODS

Participants in the beaver dam offspring study who had cognitive test data and gradable carotid artery ultrasound scans were included (n=2794, mean age: 49 years). Atherosclerosis was measured by carotid intima-media thickness (IMT) and the presence of plaque. Cognitive function was measured by the trail making test (TMT), grooved pegboard test (GPT) and mini-mental state examination (MMSE). Generalized cognitive function was defined by a summary score calculated from the TMT and GPT. Linear regression was used to evaluate the associations between carotid atherosclerosis and cognitive function tests.

RESULTS

Larger IMT was associated with lower GPT, MMSE and the summary score adjusting for multiple factors, the coefficients were: 13.8s (p<0.0001), -0.6 (p=0.007), and 0.47 (p=0.01), respectively for 1mm increase in IMT. Plaque scores were significantly associated with TMT-B, GPT, MMSE, and the summary score adjusting for age, sex and education. The associations remained statistically significant after further adjustments except for the association with TMT-B, which was attenuated and no longer significant.

CONCLUSIONS

Our results show the significant associations between markers of carotid atherosclerosis and cognitive function in a cohort of persons aged 21-84 years. Longitudinal studies are needed to further examine these associations.

A study about the frequency of taste disorders

Although 5% of the general population exhibit a functional anosmia, little is known about the frequency of gustatory disorders. Whenever taste function has been tested within large sociodemographic studies, so far only short test versions were applied making the interpretation difficult. Using two psychophysical taste tests, the validated "taste strips" and suprathreshold taste solutions of the four basic tastes sweet, sour, salty and bitter we investigated 761 healthy subjects within the age range of 5-89 years. Prior to testing, all subjects rated their taste function. According to testing with the taste strips, 5.3% scored below the result considered as hypogeusia. All four taste sprays were correctly identified by 82.3% of all subjects. Results of the two taste tests correlated positively (r = 0.33, p < 0.001), and there was a significant negative correlation between age and test results. However, we never observed complete ageusia. Misinterpretations of tastes were surprisingly common. In summary, hypogeusia was present in 5% while complete ageusia seems to be very rare, in contrast to misinterpretations of tastes.

The prevalence of age-related macular degeneration and associated risk factors

OBJECTIVES

To determine the prevalence of age-related macular degeneration (AMD) and to examine how retinal drusen, retinal pigmentary abnormalities, and early AMD are related to age, sex, and other risk factors.

PARTICIPANTS

A total of 2810 people aged 21 to 84 years participating in the Beaver Dam Offspring Study.

METHODS

The presence and severity of various characteristics of drusen and other lesions typical of AMD were determined by grading digital color fundus images using the Wisconsin Age-Related Maculopathy Grading System.

RESULTS

Early AMD was present in 3.4% of the cohort and varied from 2.4% in those aged 21 to 34 years to 9.8% in those aged 65 years or older. In a multivariable model (expressed as odds ratio; 95% confidence interval), age (per 5 years of age, 1.22; 1.09-1.36), being male (1.65; 1.01-2.69), more pack-years of cigarettes smoked (1-10 vs 0, 1.31; 0.75-2.29; >or=11 vs 0, 1.67; 1.03-2.73), higher serum high-density lipoprotein cholesterol level (per 5 mg/dL, 0.91; 0.83-0.998), and hearing impairment (2.28; 1.41-3.71) were associated with early AMD. There were no associations of blood pressure level, body mass index, physical activity level, history of heavy drinking, white blood cell count, hematocrit level, platelet count, serum total cholesterol level, or carotid intimal-medial thickness with early AMD.

CONCLUSIONS

These data indicate that early AMD is infrequent before age 55 years but increases with age thereafter. Early AMD is related to modifiable risk factors, eg, smoking and serum high-density lipoprotein cholesterol level.