Appetite loss in older adults without undernutrition: associated factors and clinical implications

Abstract

Background

The aim of this study was to investigate the clinical implications of appetite loss in older adults with normal nutritional status, prior to the development of malnutrition.

Methods

This study included a total of 755 older outpatients with normal nutritional status as determined by the Mini Nutritional Assessment (MNA ≥ 24). Council on Nutrition Appetite Questionnaire was used to assess appetite status. Patients with a CNAQ score of ≤ 28/40 were identified as having a reduced appetite. Sociodemographic characteristics, anthropometric measurements, comorbidities, number of drugs, and laboratory data at the time of outpatient clinic admission were recorded. A comprehensive geriatric assessment was performed for all patients.

Results

The mean age was 78.6 ± 7.7 years, and 66.8% were female. A total of 192 patients (25.4%) were identified with appetite loss. Individuals with appetite loss were older, more likely to be female, and more likely to have chronic kidney disease than those without appetite loss were (p < 0.05), while their educational level was lower. In the multivariate logistic regression, after adjusting for age, sex, years of education, and chronic kidney disease, there was an association between lower Tinetti Balance and Gait Scale scores, higher Geriatric Depression Scale-15 scores, and the number of medications associated with appetite loss (p < 0.05).

Conclusions

Appetite loss was observed in one out of four older adults with normal nutritional status (MNA ≥ 24). Appetite loss was associated with advanced age, female sex, lower educational level, chronic kidney disease, and polypharmacy. Older patients with appetite loss had more balance and gait disturbances and depressive symptoms even if they were well nourished.

Trial registration

Not applicable. This study is observational and not a clinical trial.

Background

Loss of appetite is a common issue among older adults living at home, in care facilities, and in hospitals. It can lead to weight loss, a greater risk of malnutrition, and negative health outcomes, including a greater risk of mortality [1]. Anorexia of ageing is a complex condition involving age-related changes in physiological and hedonic control mechanisms, along with environmental and sociocultural factors [2]. Oral processing behaviors, such as eating speed, are known to be associated with appetite in older adults [3]. Therefore, appetite loss in this population is complex and requires a comprehensive approach.

In the systematic literature review conducted by Fielding et al., the prevalence of anorexia/appetite loss, assessed via these screening tools, ranged from 3.4 to 33% among community-dwelling older adults and from 38 to 63% in inpatient care settings [4]. Anorexia or appetite loss is associated with an increased risk of mortality [4]. The largest study, which included over 1.4 million community-dwelling older adults, reported that appetite loss increased the risk of death by 30–35% [5]. Additionally, in a study of 296 older individuals hospitalized, a short nutritional assessment questionnaire (SNAQ) simplified score less than 14 was linked to a 2.62-fold greater likelihood of mortality within six months. In the same study, each 1-point decrease in the SNAQ simplified score was associated with a 22% increase in the odds of six-month mortality [6]. The relationships between anorexia/appetite loss and outcomes beyond malnutrition or mortality have been examined in terms of their associations with sarcopenia indicators, reduced physical function, increased care needs, hospitalization-related outcomes, falls, decreased health-related quality of life, and impaired cognition [4].

The term geriatric syndrome refers to a group of clinical conditions frequently observed in older adults. These syndromes include, but are not limited to, cognitive impairment, malnutrition, falls, incontinence, frailty, pressure ulcers, functional decline,, and polypharmacy [7]. Studies investigating appetite loss and geriatric syndromes have demonstrated that poor appetite is independently associated with reduced skeletal muscle mass and decreased muscle strength [8]. Another study conducted on patients with appetite loss revealed that decreased appetite was associated with lower muscle strength, reduced mobility skills, and decreased physical performance [9]. A study conducted on patients with Alzheimer’s dementia revealed that years of education, Standardized Mini-Mental State Examination (S-MMSE) score, Constipation Assessment Scale score, depression status, and the number of comorbidities were significantly associated with appetite status [10]. Since these studies included patients with impaired nutritional status, it remains unclear whether the observed outcomes are solely related to decreased appetite or are also influenced by malnutrition. However, it is well established that appetite loss contributes to the development of malnutrition, which in turn exacerbates geriatric syndromes, further complicating the health status of older adults [4].

This study aimed to investigate the effects of appetite loss on comprehensive geriatric assessment parameters in geriatric patients before significant deterioration in nutritional status occurs. To the best of our knowledge, this is the first study in the literature to examine the impact of appetite loss before the onset of malnutrition, which may contribute to the early identification of at-risk individuals and the implementation of appropriate nutritional interventions.

Methods

Study design and participants

This cross-sectional study included 2,674 patients aged 65 years and older who were admitted to a single geriatric outpatient clinic in Turkey and underwent a comprehensive geriatric assessment (CGA) between 2018 and 2024. Data were collected from electronic medical records and patient files.

Appetite was evaluated via the Council on Nutrition Appetite Questionnaire (CNAQ), a noninvasive tool consisting of a simple questionnaire (Wilson et al., 2005). A CNAQ score of ≤ 28/40 was identified as indicative of reduced appetite. The Council on Nutrition Appetite Questionnaire (CNAQ) is a screening tool developed to assess appetite status in older adults and is widely used in clinical practice. The CNAQ plays a significant role in evaluating factors such as appetite status, dietary habits, and interest in food to determine overall appetite [11].

The Mini-Nutritional Risk Assessment score consists of simple measurements and 18 questions to evaluate nutritional status. It includes anthropometric measurements (four items assessing body mass index, weight loss, brachial circumference, and calf circumference), a global assessment (six questions regarding lifestyle, medication use, and mobility), and an evaluation of dietary habits and subjective perceptions (eight questions about meal frequency, food and fluid intake, feeding autonomy, and self-perception of health and nutrition) [12]. Out of a total score of 30, a score below 23.5 indicates undernutrition [13].

The study protocol was approved by the Bezmialem Vakıf University Ethics Committee (E-54022451-050.04-183069/18.02.2025) and conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all participants prior to data collection.

Inclusion and exclusion criteria

Patients who underwent a comprehensive geriatric assessment (CGA) and laboratory evaluations on the same day were included in the study. Patients were excluded if they had undernutrition or malnutrition (n = 1,503); absence of a Mini Nutritional Assessment (n = 89) or the Council on Nutrition Appetite Questionnaire (CNAQ) (n = 39); severe chronic kidney disease (CKD; defined as estimated glomerular filtration rate [eGFR] < 30 mL/min/1.73 m²) (n = 76); acute health conditions such as infection, acute kidney failure, delirium, or stroke (n = 81); severe dementia and/or significant visual or hearing impairment that impeded communication and comprehension during the assessment (n = 71); refusal to participate in the study (n = 11); a fatal illness (n = 9); a life-threatening disease within the last six months (n = 29); or recent hospitalization for major surgery (n = 11). A total of 755 patients were included in the study after the final evaluation. A flowchart summarizing the inclusion and exclusion process is presented in Fig. 1.

Fig. 1.

Flowchart showing the inclusion and exclusion process and final sample selection

Patient characteristics

Age, sex, years of education, body mass index, and comorbidities—including hypertension, diabetes mellitus, chronic kidney disease, ischemic heart disease, dementia, and cerebrovascular diseases—were recorded.

To systematically evaluate multiple geriatric domains, a structured Comprehensive Geriatric Assessment was conducted. The assessment included the following components:

• Dependency: The Barthel Basic Activities of Daily Living Scale was used to assess dependency, with scores ranging up to 100, where lower scores indicate a higher level of dependence in daily activities [14, 15].

• The Lawton Instrumental Activities of Daily Living Scale assigns a maximum score of 8 points, with higher scores reflecting greater independence [16, 17].

• Polypharmacy: The chronic use of five or more medications is considered polypharmacy particularly in older adults [18].

• Muscle Strength: Handgrip strength (HGS) was measured via a Jamar hydraulic hand dynamometer (Sammons Preston, Inc., Bolingbrook, IL, USA) following a validated protocol [19]. Three measurements were taken from each hand, with the highest value recorded. A resting interval of at least 30 s was allowed between trials. Dynapenia was defined as a maximum handgrip strength of less than 27 kg in males and 16 kg in females [20].

• Depressive mood evaluation: Depression was assessed via the short form of the Geriatric Depression Scale (GDS-SF). A GDS score of ≥ 5 indicates an increased likelihood of depression [21].

• Neurocognitive Evaluation: The Standardized Mini-Mental State Examination (S-MMSE) was utilized to assess cognitive function, with permission obtained from Molloy DW for use. The S-MMSE includes a bedside evaluation of distinct cognitive domains, such as attention, language, memory, visuospatial abilities, and executive functions [22, 23].

• Mobility Evaluation: Mobility was assessed via the Tinetti performance-oriented mobility assessment and the timed up and go (TUG) test. Fall risk was determined via the Tinetti scale, which has a maximum score of 28 points (16 for balance and 12 for gait) [24, 25].

The TUG test measures the time it takes for a patient to rise from an armchair, walk at a comfortable and safe pace to a line marked 3 m away, turn, walk back to the chair, and sit down [26].

Laboratory measurements

Blood samples were collected in a fasting state during the same visit as the Comprehensive Geriatric Assessment (CGA). As part of the routine evaluation in our outpatient clinic, blood was drawn for biochemical, hormonal, vitamin D, and complete blood count analyses. No additional intervention was performed specifically for this study. The laboratory tests included hemoglobin, serum albumin, glucose, urea, creatinine, C-reactive protein, vitamin D, vitamin B12, folate, potassium, calcium, LDL cholesterol, HDL cholesterol, and triglycerides. The glomerular filtration rate was calculated on the basis of serum creatinine levels via the Chronic Kidney Disease Epidemiology Collaboration formula.

Statistical analysis

The normality of the data was assessed via the Kolmogorov‒Smirnov test. Continuous variables with a skewed distribution are reported as medians with interquartile ranges, whereas those with a normal distribution are presented as the means with standard deviations. Categorical variables are expressed as counts and percentages. Proportions were compared via the chi-square test or Fisher’s exact test, as appropriate. Means of continuous variables in the loss of appetite and no loss of appetite groups were compared via the Mann–Whitney U test. Logistic regression analysis was performed to assess the association between loss of appetite and geriatric syndromes. The results are expressed as odds ratios (ORs) and 95% confidence intervals. Statistical analysis was performed via SPSS version 22.0 (IBM SPSS, Chicago, IL). A P value of < 0.05 was considered statistically significant.

Results

General characteristics of the study population

A total of 755 older adults were included in the final analysis. The mean age was 78.6 ± 7.7 years, and the majority were female (n = 504, 66.8%). Dementia was present in 179 patients (23.7%). Loss of appetite was identified in 192 individuals (25.4%). Among the patients excluded due to malnutrition or risk of malnutrition, the prevalence of appetite loss was 91% and 63%, respectively (p < 0.001).

Demographic and clinical differences by appetite status

Patients with loss of appetite were significantly older (mean 80 vs. 78 years, p = 0.017) and more likely to be female (76% vs. 64%, p = 0.002). Educational attainment was lower in this group (median 5 vs. 5 years, p = 0.015). The prevalence of comorbidities was similar across the groups, except for chronic kidney disease, which was more frequent among those with appetite loss (42.3% vs. 32.4%, p = 0.027). Estimated glomerular filtration rate (eGFR) was also lower in this group (63 vs. 66 mL/min/1.73 m², p = 0.026). Laboratory parameters were largely similar, except for slightly higher serum calcium levels (median 9.5 vs. 9.4 mg/dL, p = 0.043).

Differences in geriatric assessment scores

All geriatric assessments—except for the Standardized Mini-Mental State Examination (S-MMSE)—showed statistically significant differences between patients with and without loss of appetite. Specifically, patients with appetite loss had lower scores on the Barthel Index, Lawton IADL Scale, and Tinetti Test, and had longer TUG times, higher GDS scores, and greater drug burden (all p < 0.05, Table 1).

Table 1.

Clinical characteristics of patients with and without loss of appetite

Variables	Loss of appetite (n = 192)	No loss (n = 563)	p
Demographics, comorbidities
Age, mean ± SD	80 ± 8	78 ± 8	0.017
Female sex	146 (76%)	358 (64%)	0.002
Education, median (IQR)	5 (0–8)	5 (4–10)	0.015
Diabetes mellitus	%34	%34	0.994
Hypertension	%74	%68	0.082
Chronic kidney disease	%42	%32	0.027
Ischemic heart disease	%15	%18	0.344
Cerebrovascular event	%8	%10	0.375
Dementia	%24	%23	0.888
BMI	30.5 ± 5.4	30.0 ± 5.1	0.188
Laboratory evaluation
GFR (mL/dak/1.73 m²)	63 ± 16	66 ± 18	0.026
Albumin (g/dL)	4.3 ± 0.3	4.3 ± 0.3	0.477
Triglyceride (mg/dL)	121 (90–167)	129 (96–181)	0.164
HDL (mg/dL)	53 ± 13	53 ± 14	0.486
LDL (mg/dL)	135 ± 36	134 ± 41	0.675
Calcium (mg/dL)	9.5 (9.2–9.8)	9.4 (9.1–9.7)	0.043
Hemoglobin (g/dL)	12.7 ± 1.6	12.9 ± 1.6	0.112
C-Reactive Protein (mg/L)	1.7 (0.4–5.8)	1.8 (0.2–5.9)	0.704
Vitamin D (ng/mL)	22 (15–32)	23 (14–32)	0.596
Folate (ng/mL)	6.9 (5.1–9.1)	7.2 (5.4–9.7)	0.438
VitB12 (pg/mL)	369 (270–567)	365 (254–514)	0.358
Comprehensive geriatric assessment
Barthel Index of Activities of Daily Living	89 ± 13	91 ± 12	0.023
Lawton Instrumental Activities of Daily Living Scale	16 ± 6	17 ± 6	0.007
Tinetti Balance and Gait Test	24 ± 7	25 ± 5	< 0.001
Timed Up and Go (TUG) Test	10 (11–19)	12 (10–16)	< 0.001
Geriatric Depression Scale (GDS)	4 (2–7)	2 (1–4)	< 0.001
Standardized Mini-Mental State Examination (S-MMSE)	24 ± 5	25 ± 5	0.127
Drug count	6 (4–8)	5 (3–8)	0.002
Dynapenia	46%	38%	0.051

GFR values represent estimated glomerular filtration rate (eGFR) calculated using the CKD-EPI formula

Abbreviations: GFR Glomerular Filtration Rate, BMI Body Mass Index, HDL High-Density Lipoprotein, LDL Low-Density Lipoprotein, CRP C-Reactive Protein, VitB12 Vitamin B12, GDS Geriatric Depression Scale, S-MMSE Standardized Mini-Mental State Examination, TUG Timed Up and Go Test

Compared to patients without loss of appetite, those who had loss of appetite were more likely to have geriatric depression (21% vs. 47%, p < 0.001), fall risk based on TUG test (38% vs. 53%, p < 0.001), fall risk based on Tinetti scale (12% vs. 18%, p = 0.029), dependency based on Barthel index (37% vs. 46%, p < 0.018), dependency based on Lawton index (12% vs. 16%, p = 0.260), polypharmacy (58% vs. 71%, p = 0.001), and dynapenia (38% vs. 54%, p = 0.051), while dementia rates were similar (Fig. 2).

Fig. 2.

Prevalence of common geriatric syndromes among patients with or without appetite loss

Factors independently associated with appetite loss

Univariate analysis revealed that the Tinetti scale, geriatric depression scale, and drug count were associated with loss of appetite. The multivariate regression model was adjusted for age, sex, years of education, and chronic kidney disease; the Tinetti scale (OR 0.96, 95% CI 0.92–0.99, p = 0.007), the Geriatric Depression Scale (OR 1.18, 95% CI 1.12–1.26, p < 0.001), and the number of drugs (OR 1.08, 95% CI 1.02–1.14, p = 0.009) were independent associate of loss of appetite (Table 2).

Table 2.

Associations between geriatric assessment tests and loss of appetite according to logistic regression

Geriatric assessment tests	Univariate			Multivariate*
	OR	95% CI	P	OR	95% CI	P
Barthel Index of Activities of Daily Living	1.00	0.98–1.01	0.570	-	-	-
Lawton Instrumental Activities of Daily Living Scale	0.98	0.95–1.01	0.282	-	-	-
Tinetti Balance and Gait Test	0.96	0.93–0.99	0.021	0.96	0.92–0.99	0.007
Timed Up and Go (TUG) Test	1.01	0.99–1.03	0.358	-	-	-
Geriatric Depression Scale (GDS)	1.18	1.11–1.25	< 0.001	1.18	1.12–1.26	< 0.001
Standardized Mini-Mental State Examination (S-MMSE)	0.99	0.95–1.03	0.551	-	-	-
Drug count	1.06	1.01–1.12	0.023	1.08	1.02–1.14	0.009
Dynapenia	1.39	1.00-1.93	0.052	1.14	0.74–1.74	0.559

*For each variable in the table, the multivariate regression model was adjusted for age, sex, years of education, and chronic kidney disease

Discussion

This cross-sectional study examined the relationships between appetite loss and CGA parameters in older adults before the onset of malnutrition risk. The rate of loss of appetite was 91% for malnutrition and 63% for undernutrition. One in four geriatric patients presenting to the outpatient clinic with normal nutritional status experienced appetite loss. Patients without appetite loss had a significantly longer duration of education and were more likely to be female. Chronic kidney disease was more prevalent in the appetite loss group. Among the laboratory parameters, the serum calcium levels were slightly higher in the appetite loss group than in the control group, whereas the other laboratory findings were comparable. Except for S-MMSE score and reduced muscle strength, all the comprehensive geriatric assessment parameters were more adversely affected in the group with appetite loss. Moreover, fall risk, geriatric depression, and polypharmacy were identified as independent associates of appetite loss, even before the development of malnutrition risk.

A review of the literature indicates that the prevalence of anorexia/appetite loss, as assessed via various screening tools, ranges from 3.4% to 33% among community-dwelling older adults and from 38% to 63% in inpatient care settings. The substantial variation in reported prevalence across studies can be attributed, in part, to differences in the populations assessed, study designs, and methods used to evaluate or define anorexia/appetite loss [4]. In our study, after excluding patients with impaired nutritional status, we observed appetite loss in one out of four individuals. When patients with impaired nutritional status were included in the analysis, the prevalence of loss of appetite was 91% in malnourished patients and 63% in undernourished patients. The higher rate of loss of appetite in our study compared to the literature may be attributed to the fact that our patient group consists of individuals with complex comorbidities and includes patients presenting to the hospital for various reasons. Although highly prevalent, anorexia of aging is frequently regarded as a normal aspect of aging and, as a result, often remains undiagnosed and untreated. In a study evaluating the changes in eating habits among individuals with senile anorexia, the prevalence of anorexia was found to be higher in women compared to men [27], like the findings in our study. The greater prevalence of appetite loss in women may be partly explained by social factors. For older women, the enjoyment of meal preparation may diminish once they are no longer cooking for their families or children. Additionally, eating is often a social behavior closely tied to social interactions and events [28]. Furthermore, in our study, the greater mean age of the women may have contributed to this finding. In our study, we found that individuals with a longer duration of education had a lower prevalence of appetite loss. This may possibly be attributed to greater health literacy and nutritional awareness often associated with higher educational attainment [29].

As kidney function decreases, metabolic alterations frequently lead to changes in appetite and food intake. Uremia, along with associated inflammation, hormonal imbalances, metabolic acidosis, and altered gut motility, can contribute to reduced dietary intake as chronic kidney disease progresses [30]. Consistent with this information, our study revealed that chronic kidney disease was more prevalent in the appetite loss group. Loss of appetite is one of the symptoms of hypercalcemia [31].

Malnutrition (undernutrition) remains a major global health concern for older adults and is driven by multiple factors, such as appetite loss, polypharmacy, dementia, frailty, swallowing difficulties, social isolation, and poverty [32]. Malnutrition in the aging population is associated with an increased risk of falls, a higher prevalence of depression, an elevated risk of sarcopenia, and polypharmacy [33–36]. In the literature examining appetite loss and geriatric syndromes, the ilSIRENTE study by Landi et al., which included 354 community-dwelling older adults, reported an association between anorexia of aging and sarcopenia [37]. However, their study did not use any formal assessment tool to evaluate appetite loss and did not exclude patients with malnutrition. In another study conducted by Ilhan et al., poor appetite was found to be independently associated with lower skeletal muscle mass and decreased muscle strength [8]. However, this study also did not exclude malnutrition, which is a risk factor for sarcopenia. In our study, no significant association was found between muscle strength loss and appetite loss. This may be due to other factors influencing muscle strength or the exclusion of patients with malnutrition and those at risk of malnutrition from our study.

The association between depression and appetite in older adults has been extensively investigated. In a study examining the associations between appetite loss and psychosocial factors in community-dwelling older adults, depressive symptoms were found to be linked to appetite loss [38]. In this study, where appetite was assessed via the SNAQ, 67.2% of individuals were without nutritional risk. Even after excluding malnutrition, which can influence depression, our study still revealed a significant association between appetite loss and depression. Changes in appetite are among the symptoms of depression [39]; additionally, a reduction in caloric intake may have contributed to worsening depressive mood.

The only study in the literature evaluating the association between fall risk and appetite loss using the Tinetti scale was conducted in older patients with chronic kidney disease [40]. In this study, lower Tinetti scores were significantly associated with appetite loss in the univariate analysis; however, after adjusting for confounders in the multivariate regression analysis, this association was no longer significant. In our study, univariate analysis revealed an association between the risk of falls and appetite loss. Furthermore, in the multivariate regression model adjusted for age, sex, years of education, and chronic kidney disease, the Tinetti scale score was identified as an independent associate of appetite loss. Therefore, an increased risk of falls should be considered in patients presenting with appetite loss. Fall prevention is necessary for older adults suffering from appetite loss. In a study conducted on 1,192 community-dwelling older adults aged >70 years, 25 individuals were identified with cognitive frailty, and a low CNAQ score was significantly associated with falls in the cognitive frailty group [41]. In our study, frailty was not assessed; however, the increased risk of falls may have been influenced by cognitive frailty. As previously mentioned, a study conducted on HD patients revealed an association between appetite and the number of sleep medications used [41]. It is well known that medications used for sleep can cause sedation [42]. In our study, we did not evaluate specific drug classes while assessing polypharmacy. The increased fall risk observed in patients with appetite loss may be attributed to sedation caused by the sleep medications they are taking.

We recognize the limitations of this study, particularly its cross-sectional design, which restricts our ability to establish definitive cause‒and‒effect relationships. While we identified an association, causation could not be determined, and the observed relationships may be bidirectional. However, the strengths of our study include a sufficient sample size and the exclusion of individuals who are malnourished and at risk of malnutrition, allowing for a more precise evaluation of appetite loss. Although acute conditions were part of the exclusion criteria, we cannot completely rule out the possibility that unrecognized transient health problems may have influenced appetite at the time of assessment. On the other hand, this is the first study to investigate the relationship between poor appetite and comprehensive geriatric assessment in older adults with preserved nutritional status. Moreover, medication classes known to influence appetite (e.g., antidepressants, antipsychotics) were not specifically recorded in this study; polypharmacy was assessed solely based on the total number of medications used. Further research is needed to validate these findings.

Conclusion

One in four older adults who were presented to the geriatric outpatient clinic without existing nutritional disorders experienced appetite loss. Appetite loss is associated with advanced age, female sex, lower educational level, and chronic kidney disease. These patients exhibited more balance and gait disturbances, depressive symptoms, and greater medication use. Therefore, in older adults with appetite loss, it is crucial to implement appropriate clinical approaches addressing depression and polypharmacy alongside nutritional support. This may also contribute to reducing the risk of falls in these patients.

Abbreviations

SNAQ

Short Nutritional Assessment Questionnaire

S-MMSE

StandardizedMini-Mental State Examination

CNAQ

Council on Nutrition Appetite Questionnaire

CGA

Comprehensive Geriatric Assessment

CKD

Chronic kidney disease

HGS

Handgrip strength

GDS-SF

Geriatric Depression Scale-Short Form

TUG

Timed Up and Go

ORs

odds ratios

Authors’ contributions

All authors have significantly contributed to the work both directly and intellectually and have given their approval for publication.

Funding

No funding was provided for this study.

Data availability

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethics approval and consent to participate

This study was conducted in accordance with the principles of the Declaration of Helsinki and received approval from the Bezmialem Vakıf University Ethics Committee (E-54022451-050.04-183069/18.02.2025).

All participants provided written informed consent prior to participation in the study.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.