Auris Nasus Larynx xxx (2015) xxx–xxx

G Model

ANL-1998; No. of Pages 6

Effects of nutritional status and cognitive ability on olfactory functionin geriatric patients

Sung-Yong Jin a,1, Hye Seon Jeong b,1, Jin Woo Lee a, Ki Ryun Kwon a,Ki-Sang Rha a,c, Yong Min Kim a,c,*a Department of Otorhinolaryngology-Head and Neck Surgery, Chungnam National University School of Medicine, Daejeon, Republic of Koreab Department of Neurology, Chungnam National University School of Medicine, Daejeon, Republic of Koreac Research Institute for Medical Science, Chungnam National University School of Medicine, Daejeon, Republic of Korea

A R T I C L E I N F O

Article history:

Received 22 January 2015

Accepted 29 June 2015

Available online xxx

Keywords:

Olfaction

Odor identification

Nutrition

Aging

Cognitive impairment

Malnutrition

Smell disorder

A B S T R A C T

Objective: The aim of this study was to investigate the prevalence of olfactory dysfunction and evaluate

the relationship between olfactory function and nutritional status, comorbidity, and the results of a

neurocognitive test in geriatric patients who do not suffer from neurodegenerative disease.

Materials and methods: A total of 45 patients who visited the Geriatric Health Center of Chungnam

National University Hospital were enrolled in this study. Olfactory function was assessed using a Korean

Version of Sniffin’ Stick Test II. Cognitive status of all participants was assessed with the MMSE-K (Korean

version of the Mini-Mental State Examination). Nutritional status was assessed with body mass index,

Mini-Nutritional Assessment (MNA), and serum total protein and albumin.

Results: A total of 45 participants were enrolled in this study. Of these subjects, 28 were men and

17 were women, with a mean age of 71.7 � 5.16 years. Nine (20%) were normosmia, 13 (28.9%) were

hyposmia, and 23 (51.1%) were anosmia. Thirty-six patients (80%) suffered from olfactory dysfunction

(anosmia or hyposmia). MMSE score showed significant correlation with MNA score. There were significant

negative correlations between age and total TDI (threshold, discrimination, and identification) score,

discrimination score, identification score, and MMSE score. MMSE score showed significant correlation with

discrimination score and identification score. However, MNA score did not show any significant correlation

with olfactory function test results.

Conclusion: Although olfactory function was not influenced by nutritional status, abilities of

discrimination and identification of odors were associated with cognitive function in geriatric patients.

� 2015 Elsevier Ireland Ltd. All rights reserved.

Contents lists available at ScienceDirect

Auris Nasus Larynx

jo u rn al h om epag e: ww w.els evier .c o m/lo cat e/anl

1. Introduction

Olfactory dysfunction may be associated with failure torecognize danger and may accompany social, psychological, andnutritional problems, as well as decrease quality of life [1]. It hasbeen known that the overall prevalence of olfactory dysfunction isestimated around 5% and that the prevalence increases exponen-tially with age [1,2].

Age-related olfactory loss (presbyosmia) affects critical func-tions, such as nutrition, immunity, mood, behavior, and sexuality[3,4], and has been known to be related to high risk of mortality

* Corresponding author at: Department of Otolaryngology-Head and Neck

Surgery, Chungnam National University Hospital, 282 Munhwa-ro, Jung-gu,

Daejeon 301-721, Republic of Korea. Tel.: +82 42 280 7696; fax: +82 42 253 4059.

E-mail address: entkym@cnu.ac.kr (Y.M. Kim).1 These authors contributed equally to the completion of this article.

Please cite this article in press as: Jin S-Y, et al. Effects of nutritionpatients. Auris Nasus Larynx (2015), http://dx.doi.org/10.1016/j.anl.

http://dx.doi.org/10.1016/j.anl.2015.06.009

0385-8146/� 2015 Elsevier Ireland Ltd. All rights reserved.

[5]. Furthermore, the relationship between olfaction and mortalitymay be largely mediated by cognitive impairment [5].

Nutrition is known to be an important element of health andaffects the aging process in the geriatric population [6]. The declinein sense of smell inhibits flavor perception and influences foodintake in older people and can influence the type of food eaten.Indeed, it has been shown that olfaction loss (hyposmia) isassociated with reduced interest in and intake of food [7]. Further-more, the prevalence of malnutrition is increasing in the geriatricpopulation and its association with olfactory dysfunction alone orin combination with taste loss has been demonstrated [8].

Although olfactory function is a very important element innutritional status and there is an increasing evidence of arelationship between malnutrition and olfaction loss in olderadults, little research has been conducted to elucidate this issue.The aim of this study was to investigate the prevalence of olfactorydysfunction and to evaluate the relationship between olfactory

al status and cognitive ability on olfactory function in geriatric2015.06.009

S.-Y. Jin et al. / Auris Nasus Larynx xxx (2015) xxx–xxx2

G Model

ANL-1998; No. of Pages 6

function and nutritional status, comorbidity, and the results of aneurocognitive test in Korean geriatric patients who do not sufferfrom neurodegenerative disease.

2. Materials and methods

2.1. Patients

A total of 45 patients who visited the Geriatric Health Center ofChungnam National University Hospital between August 2013 andMarch 2014 were enrolled in this study. The population did notinclude hospitalized patients, but included only those from an out-patient clinic, specifically from the Geriatric Health Center. Mostpatients visited this center to evaluate mild headache or cognitiveimpairments, and all patients undertook a brain MRI to excludeorganic brain disease. Endoscopic examination of the nasal cavitywas conducted to exclude sinonasal inflammation, such asrhinosinusitis, nasal polyps, or sinonasal tumors, and obstructivelesions of the olfactory clefts. Additional information was obtainedfrom brain MRI or plain radiography of the paranasal sinuses toexclude sinonasal diseases. Exclusion criteria were age less than65 years; withdrawal of informed consent; diagnosis of Parkin-son’s, Alzheimer disease’s, or other organic brain disease;moderate or severe cognitive impairment defined as a MiniMental State Examination (MMSE) score of less than 20; sinonasalabnormalities, such as severe nasal septal deviation, rhinosinusitis,nasal polyposis, sinonasal tumors, or severe allergic rhinitis; andsmoking within the preceding year.

Patient characteristics are included in Table 1. Informedconsent was obtained from each patient before enrollment inthe study. The study was approved by the Institutional ReviewBoard of the Chungnam National University Hospital.

2.2. Olfactory function test

Olfactory function was assessed using a validated test, theKorean version of Sniffin’ Stick Test II (KVSS II, Kwang Woo, Seoul,Korea) [9]. It consists of 3 different subtest, including a threshold(T), discrimination (D), and identification (I) test. The tests wereperformed in the same way as the Sniffin’ Stick test and previouswork [9,10]. The threshold was defined as the concentration atwhich n-butanol (highest concentration 4%, 1:2 serial dilutions to16 steps) was correctly identified four times in a row. For thediscrimination test, triplets of odorants (two were identical, onedifferent) were presented and subjects were asked to choose theodd odorant. The identification test involved 16 odors familiar toKoreans. The sums of the three tests were presented as aThreshold-Discrimination-Identification (TDI) score. Total (TDI)scores of 0 to 20 were defined as ‘anosmia’, 21 to 24 as ‘hyposmia’,

Table 1Patients characteristics.

Total (n = 45) (mean � SD) Normosmia (

Age 71.7 � 5.16 69.3 � 4.2

Male (No.) 28 5

Female (No.) 17 4

BMI 24.0 � 3.2 23.3 � 2.5

Total protein 6.84 � 0.62 7.1 � 0.75

Albumin 4.07 � 0.39 4.09 � 0.54

KVSSII score 20.0 � 5.7 28.3 � 3.2

MNA 23.6 � 2.9 22.6 � 3.1

MMSE 26.4 � 2.5 27.7 � 2.0

No. of comorbid disease 3.2 � 1.4 3.1 � 1.4

Barthel Index 100 100

BMI, body mass index; KVSSII, Korean version of Sniffin’ Stick Test II; MNA, Mini-Nutr

Please cite this article in press as: Jin S-Y, et al. Effects of nutritionpatients. Auris Nasus Larynx (2015), http://dx.doi.org/10.1016/j.anl.

and 25 to 48 as ‘normosmia’. The criteria used were based onprevious work [9].

2.3. Assessment of functional status and cognitive function

To evaluate self-caring capacity, Barthel Index was used.Barthel Index consists of 10 items that measure a person’s dailyfunction, specifically the activities of daily living and mobility. Theitems include feeding, moving from a wheelchair to bed andreturning, grooming, transferring to and from the toilet, bathing,walking on a level surface, going up and down stairs, dressing, andcontinence of bowels and bladder. Barthel Index is scored from 0 to100, with 0 points indicating complete care dependency. Cognitivestatus of all participants was assessed with the MMSE-K (Koreanversion of the Mini-Mental State Examination). The MMSEcontains 19 items and the maximum score is 30 points (10 pointsfor orientation, 6 for verbal memory, 5 for concentration andcalculation, 5 for language, 3 for praxis, and 1 for visuospatialconstruction) [11]. A score of more than 25 points indicates anormal cognitive status.

2.4. Determination of nutritional status

Blood sampling was performed to measure serum total proteinand albumin levels in each patient. Nutritional status was assessedwith BMI (kg/m2) and Mini-Nutritional Assessment (MNA). TheMNA consists of 18 items including anthropometric measurementsand questions on weight loss within the preceding 3 months,mobility, food intake, and self-perception of the patient. It is avalidated instrument to screen for malnutrition in older patients[6,12]. Participants were divided into 3 groups according tonutritional status: malnutrition (a score of less than 17), risk ofmalnutrition (a score of between 17 and 23.5), and well-nourishedpatients (a score of over 24 points) [12,13].

2.5. Statistical analysis

All statistical analyses were performed using GraphPad Prism 5(GraphPad, Inc, San Diego, CA, USA). Paired or unpaired Student t-test, Mann–Whitney U-test, and Spearman correlation tests wereapplied with significance levels set at p < .05.

3. Results

3.1. Patient characteristics

A total of 45 participants were enrolled in this study. Of thesesubjects, 28 were men and 17 were women, with a mean age of71.7 � 5.16 years (range, 65–89). Nine (20%) were classified asnormosmia, 13 (28.9%) were hyposmia, and 23 (51.1%) were anosmia.

n = 9) Hyposmia (n = 13) Anosmia (n = 23) p-value

70.2 � 4.9 73.4 � 5.0 .643

10 13 .431

3 10

24.4 � 3.1 24.0 � 3.5 .464

6.78 � 0.54 6.77 � 0.61 .149

4.02 � 0.32 4.08 � 0.37 .485

22.0 � 1.1 15.7 � 3.3 .000

24.9 � 2.7 23.3 � 2.9 .473

26.6 � 2.7 25.9 � 2.4 .738

3.6 � 1.7 2.9 � 1.1 .439

100 100

itional Assessment; MMSE, Mini-Mental State Examination.

al status and cognitive ability on olfactory function in geriatric2015.06.009

Fig. 1. Correlations among the olfactory function test and between Mini-Nutritional Assessment (MNA) and Mini-Mental State Examination (MMSE) scores. There were

significant correlations between TDI (total) score and threshold (A), discrimination (B), or identification (C) score in this study. In addition, MMSE score showed significant

correlation with MNA score (D). *a, p < .0001 and b-Coefficient = 0.722 (A), 0.675 (B), 0.798 (C); *b, p = .016 and b-Coefficient = 0.356 (D).

S.-Y. Jin et al. / Auris Nasus Larynx xxx (2015) xxx–xxx 3

G Model

ANL-1998; No. of Pages 6

Thirty-six patients (80%) suffered from olfactory dysfunction (anos-mia or hyposmia). Barthel Index of all subjects was 100 points, andmean BMI, KVSS II, MNA, and MMSE scores were 24.0 � 3.2,20.0 � 5.7, 23.6 � 2.9, and 26.4 � 2.5, respectively (Table 1).

Comorbid diseases were also analyzed, and the most commoncomorbid disease was hypertension (n = 27), followed by hyper-lipidemia (n = 14), diabetes mellitus (DM, n = 8), urology disease(n = 8), peripheral vascular disease (n = 6), cardiovascular disease(n = 5), skeletal disease (n = 4), and gastrointestinal disease (n = 2).There was no significant correlation between olfactory functiontest and number of comorbid diseases. However, number ofcomorbid disease showed significant correlation with BMI(p = .0373).

3.2. Correlations of olfactory function test, MNA, and MMSE

There were significant correlations between TDI (total) scoreand threshold (Fig. 1A, p < .0001), discrimination (Fig. 1B,p < .0001), or identification score (Fig. 1C, p < .0001) in this study.In addition, MMSE score showed significant correlation withMNA score (Fig. 1D, p = .0116). There were significant negative

Table 2Linear regression analysis of factors influencing cognitive function.

Mini-Mental State Examination

b-Coefficient SE

Age �0.234 0.066

Gender �0.197 0.757

No. of disease �0.122 0.275

MNA 0.356 0.121

KVSSII score 0.226 0.064

Threshold �0.095 0.139

Discrimination 0.340 0.157

Identification 0.280 0.130

MNA, Mini-Nutritional Assessment; KVSSII, Korean version of Sniffin’ Stick Test II.

Please cite this article in press as: Jin S-Y, et al. Effects of nutritionpatients. Auris Nasus Larynx (2015), http://dx.doi.org/10.1016/j.anl.

correlations between age and TDI (Fig. 2A, p = .0380), discrimina-tion (Fig. 2C, p = .0054), identification (Fig. 2D, p = .0438), andMMSE scores (Fig. 2E, p = .0009). Threshold and MNA scores did notshow any significant correlation with age (Fig. 2B and 2F).

3.3. Analysis of factors influencing cognitive function and nutritional

status

MMSE score was affected by discrimination and identificationscores (Table 2). However, MNA score did not show any significantcorrelation with discrimination and identification scores, thoughthere was a significant negative correlation with threshold score(Table 3).

3.4. Analysis of factors influencing body mass index

In a linear regression analysis with BMI as dependent variable,age, number of disease, MMSE, MNA, and threshold score of KVSS IItest were factors with significant influence (Table 4). However, BMIwas affected by total score, discrimination score, or identificationscore.

p-value OR (95% CI)

.001 �0.234 [�0.367 to �0.102]

.194 �0.998 [�2.524 to 0.529]

.426 �0.221 [�0.776 to 0.334]

.016 0.301 [0.058 to 0.545]

.135 0.098 [�0.032 to 0.228]

.535 �0.087 [�0.366 to 0.193]

.022 0.371 [0.055 to 0.687]

.037 0.249 [�0.014 to 0.511]

al status and cognitive ability on olfactory function in geriatric2015.06.009

Fig. 2. Correlations between age and olfactory function test, Mini-Mental State Examination (MMSE) or Mini-Nutritional Assessment (MNA) scores. There were significant

negative correlations between age and TDI (A), discrimination (C), identification (D), and MMSE scores (E). *a, p = .0380 and b-Coefficient = �0.312; *b, p = .0054 and b-

Coefficient = �0.408; *c, p = .0438 and b-Coefficient = �0.302; *d, p = .0009 and b-Coefficient = �0.479.

Table 3Linear regression analysis of factors influencing nutritional status.

Mini-Nutritional Assessment

b-Coefficient SE p-value OR (95% CI)

Age �0.282 0.085 .061 �0.163 [�0.334 to 0.008]

Gender �0.430 0.823 .003 �2.571 [�4.232 to �0.911]

No. of disease �0.018 0.328 .906 �0.039 [�0.700 to 0.622]

MMSE 0.356 0.168 .016 0.420 [0.081 to 0.760]

KVSSII score �0.029 0.078 .852 �0.015 [�0.172 to 0.143]

Threshold �0.298 0.157 .046 �0.322 [�0.638 to �0.005]

Discrimination 0.186 0.193 .221 0.240 [�0.150 to 0.630]

Identification 0.080 0.159 .600 0.084 [�0.237 to 0.406]

MMSE, Mini-Mental State Examination; KVSSII, Korean version of Sniffin’ Stick Test II.

S.-Y. Jin et al. / Auris Nasus Larynx xxx (2015) xxx–xxx4

G Model

ANL-1998; No. of Pages 6

Serum total protein and albumin levels were measured in eachpatient; however, they did not show any significant correlationswith BMI, MNA, or TDI score in this study (Fig. 3).

4. Discussion

This study was conducted to investigate the prevalence ofolfactory dysfunction and the relationship between an olfactoryfunction test and nutritional status, comorbidity, and the results ofa neurocognitive test in Korean geriatric patients. The prevalenceof olfactory dysfunction (anosmia or hyposmia) was 24.5–70.2% in

Please cite this article in press as: Jin S-Y, et al. Effects of nutritionpatients. Auris Nasus Larynx (2015), http://dx.doi.org/10.1016/j.anl.

previous studies, and olfactory performance was found to decreasewith age [2,12,14]. Prevalence of olfactory dysfunction in our studywas 80% (36 out of 45), and olfactory functioning also negativelycorrelated with increasing age. The higher prevalence of olfactorydysfunction in our patients was probably due to the fact that theywere not from the general population. They suffered from variousdiseases, such as hypertension, DM, hyperlipidemia, and periph-eral vascular disease, and were consequently seeking therapy forthese diseases at the Geriatric Health Center.

It has been shown that men tend to have a poorer olfactoryfunction than women, and the odds of men developing olfactory

al status and cognitive ability on olfactory function in geriatric2015.06.009

Table 4Linear regression analysis of factors influencing body mass index.

Body Mass Index

b-Coefficient SE p-value OR (95% CI)

Age �0.457 0.085 .002 �0.287 [�0.459 to �0.115]

Gender 0.095 0.986 .535 0.617 [�1.371 to 2.605]

No. of disease 0.311 0.338 .037 0.727 [0.045 to 1.409]

MMSE 0.327 0.185 .028 0.420 [0.047 to 0.792]

MNA 0.330 0.156 .027 0.358 [0.043 to 0.673]

KVSSII score �0.113 0.084 .460 �0.063 [�0.233 to 0.107]

Threshold �0.359 0.167 .015 �0.421 [�0.757 to �0.085]

Discrimination 0.116 0.212 .449 0.162 [�0.266 to 0.590]

Identification 0.024 0.174 .875 0.027 [�0.323 to 0.378]

MMSE, Mini-Mental State Examination; MNA, Mini-Nutritional Assessment; KVSSII, Korean version of Sniffin’ Stick Test II.

Fig. 3. Correlations between and serum total protein or albumin levels and body mass index (BMI, A and B), Mini-Nutritional Assessment (MNA) scores (C and D), and TDI

(total) score of olfactory function test and b-Coefficient = 0.170 (A), 0.192 (B), �0.147 (C), 0.100 (D), 0.094 (E), and 0.017 (F).

S.-Y. Jin et al. / Auris Nasus Larynx xxx (2015) xxx–xxx 5

G Model

ANL-1998; No. of Pages 6

dysfunction were more than double compared with women[2,14,15]. In the present study, men also showed a higher prevalenceof olfactory impairment (n = 23, 51%) than women (n = 13, 29%) eventhough our patient sample population was smaller.

Total score of KVSS II showed very strong correlations with itsthreshold, discrimination, and identification tests in the presentstudy (Fig. 1). In spite of the strong correlation among the tests,each test demonstrates unique characteristics when it is conductedseparately and may contribute to localize underlying pathology. Ifonly the ability of discrimination or identification is affected,

Please cite this article in press as: Jin S-Y, et al. Effects of nutritionpatients. Auris Nasus Larynx (2015), http://dx.doi.org/10.1016/j.anl.

impairment of the central nervous system could be suspected,while isolated shifting of the olfactory threshold tends to indicateperipheral damage [16,17]. In the present study, MMSE, whichassessed cognitive function of the geriatric patients, showedsignificant positive correlation with discrimination and identifica-tion scores. As patients with severe cognitive dysfunction andParkinson’s disease are known to have olfactory dysfunction [18],and olfactory dysfunction could be an early symptom ofneurodegenerative diseases such as Parkinson’s disease andAlzheimer dementia [19], we excluded these patients from our

al status and cognitive ability on olfactory function in geriatric2015.06.009

S.-Y. Jin et al. / Auris Nasus Larynx xxx (2015) xxx–xxx6

G Model

ANL-1998; No. of Pages 6

study. Despite the exclusion of these patients, decreasing cognitivefunction scores correlated with decreasing discrimination andidentification scores. Aging is known to be associated with ageneral decline in cognitive abilities [20], which would explain thedecreasing discrimination and identification scores in this study.

Nutrition is an important element of health in the geriatricpopulation, and some studies have reported that it can beinfluenced by diminished senses of smell and taste [21,22].Whereas, other studies have reported that olfactory dysfunctionwas not associated with nutritional status [12,15,23]. In our study,nutritional status was evaluated by MNA score, BMI, and serumtotal protein and albumin level. BMI showed significant correlationwith MNA score. However, serum protein or albumin level did notshow any significant correlation with BMI or MNA score. Serumproteins synthesized by the liver have been used as markers ofnutrition. Serum albumin is the most commonly used marker sinceit can predict mortality in older people [6]. However, albumin canbe affected by not only nutritional state but also by other factors,including inflammation and infection. This limits their usefulness,especially in acutely unwell patients [6]. Measurement of BMI andMNA score, however, may be suitable for evaluating nutritionalstatus. Nonetheless, the parameters that we used did not show anysignificant correlation with olfactory function test results exceptthreshold score and BMI (Table 4). The threshold score of the KVSSII test showed significant negative correlation with BMI, and thisresult could be explained by the fact that older patients withdecreasing olfactory function have compensatory strategies thatmay have already developed such as preference for foods withenhanced primary taste qualities (e.g., salty or sugary)[12,24]. These compensatory strategies could result in increasedfood intake and weight gain in the patients with olfactorydysfunction.

In addition, pathologic changes during aging, such as chronicdisease and psychological illness, may play roles as importantetiologies of malnutrition in older people. We investigatedcomorbid disease in our patients and analyzed the relationshipwith olfactory function test results and nutritional assessment. Thenumber of comorbid diseases showed significant positive correla-tion with BMI. Measurement of BMI in geriatric patients has certainlimits such as height change due to vertebral collapse and loss ofmuscle tone. In these cases, measurement of certain bodysegments, such as leg, arm and arm span, could be reliable toobtain height [6,25]. In addition, there could be confoundingfactors such as ascites and edema to warrant avoiding use of BMI asa surrogate marker of nutrition [6].

In the present study, cognitive function test (MMSE score)showed significant correlation with BMI and MNA score. Theseresults indicated that cognitive function of geriatric patients could beassociated with nutritional state. However, nutritional status did notimpact on olfactory function in these patients, and olfactory deficitsin this geriatric population with normal functionality and perfor-mance did not have any influence on impaired nutritional status.

Apart from teratogenic and pathological effects of zincdeficiency, such as the occurrence of skin lesions, anorexia, growthretardation, depressed wound healing, altered immune function,and impaired night vision, alterations in taste and smell acuity inanimal models and human patients suffering from zinc deficiencyhave been observed. However, it is known that severe zincdeficiency is rare and difficult to substantiate. Unfortunately, wedid not routinely examine serum zinc levels in this study. Becausewe included patients from an outpatient clinic with highfunctioning and performance and their nutritional status wasrelatively good, there was no possibility that zinc deficiencypatients were included in this study.

Although olfactory function was not influenced by nutritionalstatus, the abilities of discrimination and identification of odors

Please cite this article in press as: Jin S-Y, et al. Effects of nutritionpatients. Auris Nasus Larynx (2015), http://dx.doi.org/10.1016/j.anl.

were associated with cognitive function in geriatric patients. As thestudy participants were higher functioning older adults whovisited our Geriatric Health Center, they were not representative ofthe general elder population. Therefore, further studies ofparticipants with high risk of nutritional deficiency and largersample populations will be needed in the future.

Financial disclosure

This work (research) was supported by Chungnam NationalUniversity Hospital Research Fund 2013.

References

[1] Hoffman HJ, Ishii EK, MacTurk RH. Age-related changes in the prevalence ofsmell/taste problems among the United States adult population. Results of the1994 disability supplement to the National Health Interview Survey (NHIS).Ann N Y Acad Sci 1998;855:716–22.

[2] Bramerson A, Johansson L, Ek L, Nordin S, Bende M. Prevalence of olfactorydysfunction: the skovde population-based study. Laryngoscope 2004;114:733–7.

[3] Schiffman SS, Graham BG. Taste and smell perception affect appetite andimmunity in the elderly. Eur J Clin Nutr 2000;54(Suppl. 3):S54–63.

[4] Pinto JM, Schumm LP, Wroblewski KE, Kern DW, McClintock MK. Racialdisparities in olfactory loss among older adults in the United States. J GerontolA Biol Sci Med Sci 2014;69:323–9.

[5] Gopinath B, Sue CM, Kifley A, Mitchell P. The association between olfactoryimpairment and total mortality in older adults. J Gerontol A Biol Sci Med Sci2012;67:204–9.

[6] Ahmed T, Haboubi N. Assessment and management of nutrition in olderpeople and its importance to health. Clin Interv Aging 2010;5:207–16.

[7] Mathey MF, Siebelink E, de Graaf C, Van Staveren WA. Flavor enhancement offood improves dietary intake and nutritional status of elderly nursing homeresidents. J Gerontol A Biol Sci Med Sci 2001;56:M200–5.

[8] Morley JE. Anorexia of aging: physiologic and pathologic. Am J Clin Nutr1997;66:760–73.

[9] Cho JH, Jeong YS, Lee YJ, Hong SC, Yoon JH, Kim JK. The Korean version of theSniffin’ stick (KVSS) test and its validity in comparison with the cross-culturalsmell identification test (CC-SIT). Auris Nasus Larynx 2009;36:280–6.

[10] Kobal G, Hummel T, Sekinger B, Barz S, Roscher S, Wolf S. Sniffin’ sticks:screening of olfactory performance. Rhinology 1996;34:222–6.

[11] Kim TH, Jhoo JH, Park JH, Kim JL, Ryu SH, Moon SW, et al. Korean version of minimental status examination for dementia screening and its’ short form. Psy-chiatry Investig 2010;7:102–8.

[12] Smoliner C, Fischedick A, Sieber CC, Wirth R. Olfactory function and malnu-trition in geriatric patients. J Gerontol A Biol Sci Med Sci 2013;68:1582–8.

[13] Vellas B, Guigoz Y, Garry PJ, Nourhashemi F, Bennahum D, Lauque S, et al. TheMini Nutritional Assessment (MNA) and its use in grading the nutritional stateof elderly patients. Nutrition 1999;15:116–22.

[14] Vennemann MM, Hummel T, Berger K. The association between smoking andsmell and taste impairment in the general population. J Neurol 2008;255:1121–6.

[15] Schubert CR, Cruickshanks KJ, Fischer ME, Huang GH, Klein BE, Klein R, et al.Olfactory impairment in an adult population: the Beaver Dam Offspring Study.Chem Senses 2012;37:325–34.

[16] Huttenbrink KB, Hummel T, Berg D, Gasser T, Hahner A. Olfactory dysfunction:common in later life and early warning of neurodegenerative disease. DtschArztebl Int 2013;110:1–7. e1.

[17] Hedner M, Larsson M, Arnold N, Zucco GM, Hummel T. Cognitive factors inodor detection, odor discrimination, and odor identification tasks. J Clin ExpNeuropsychol 2010;32:1062–7.

[18] Schubert CR, Carmichael LL, Murphy C, Klein BE, Klein R, Cruickshanks KJ.Olfaction and the 5-year incidence of cognitive impairment in an epidemio-logical study of older adults. J Am Geriatr Soc 2008;56:1517–21.

[19] Conti MZ, Vicini-Chilovi B, Riva M, Zanetti M, Liberini P, Padovani A, et al. Odoridentification deficit predicts clinical conversion from mild cognitive im-pairment to dementia due to Alzheimer’s disease. Arch Clin Neuropsychol2013;28:391–9.

[20] Olofsson JK, Ronnlund M, Nordin S, Nyberg L, Nilsson LG, Larsson M. Odoridentification deficit as a predictor of five-year global cognitive change: interac-tive effects with age and ApoE-epsilon4. Behav Genet 2009;39:496–503.

[21] Hummel T, Nordin S. Olfactory disorders and their consequences for quality oflife. Acta Otolaryngol 2005;125:116–21.

[22] Toller SV. Assessing the impact of anosmia: review of a questionnaire’sfindings. Chem Senses 1999;24:705–12.

[23] Mattes RD. The chemical senses and nutrition in aging: challenging oldassumptions. J Am Diet Assoc 2002;102:192–6.

[24] Henkin RI. Effects of smell loss (hyposmia) on salt usage. Nutrition 2014;30:690–5.

[25] Hickson M, Frost G. A comparison of three methods for estimating height inthe acutely ill elderly population. J Hum Nutr Diet 2003;16:13–20.

al status and cognitive ability on olfactory function in geriatric2015.06.009