Nutritional Assessment in Older Persons

Purpose. Nutritional assessment answers four questions (Essentials, Table 3-12): Is there reason to suspect malnutrition? Of which nutrient(s) and to what extent? What is the pathophysiological mechanism? What is the underlying etiology?

Why assessment is different in the elderly. No single parameter is adequate — anthropometric variables are not highly correlated with biochemical or haematologic indicators, and the effect of ageing on lean body mass is so great that lean mass alone is a poor reflection of nutritional status. Assessment must therefore be multi-parameter and multi-domain.

The standard two-step (now three-step) approach. Step 1 — SCREEN every older person with a validated tool. Step 2 — DIAGNOSE using GLIM criteria. Step 3 — GRADE severity and identify the mechanism, then plan intervention.

Mini Nutritional Assessment (MNA) — the geriatric standard. The full MNA is multidimensional and identifies malnourished elders or those at risk, whatever the cause. MNA-SF has equivalent performance: 12– 14 = normal, 8–11 = at risk, 0–7 = malnourished. Body mass is entered as BMI (0 = <19, 1 = 19–20.9, 2 = 21– 22.9, 3 = ≥23) or, if BMI is unavailable, calf circumference (0 = <31 cm, 3 = ≥31 cm).

MNA components (six domains). (A) decline in food intake over 3 months, (B) weight loss over 3 months, (C) mobility, (D) psychological stress or acute illness in 3 months, (E) neuropsychological problems (dementia/depression), (F) BMI or calf circumference.

Performance and prognostic value. MNA is 96% sensitive and 60% specific for body weight loss. Subjects with a normal MNA had lower mortality (RR 0.35, 95% CI 0.18–0.66) than those with an abnormal score. Those “at risk” had more acute illness, more assistance needs and more weight loss. MNA is a powerful independent prognostic factor, especially in cancer, and can assess cancer cachexia. A six-item version has equivalent predictive value.

Other validated tools. SGA (predicts mortality but classifies more patients as well-nourished than MNA — those “well-nourished” by MNA had better 3-year survival), MUST, NRS-2002, and the Geriatric Nutritional Risk Index (GNRI), which predicts healthcare costs and hospitalisation.

SNAQ (Simplified Nutritional Appetite Questionnaire) — four questions on appetite, early satiety, taste of food, and number of meals per day, each scored 1–5. A score <14 indicates significant risk of weight loss. Recommended by Pathy’s as a rapid appetite screen.

Screening question in routine geriatric review (Pathy’s Function Assessment Scales): ask “Have you lost weight?” and record height and weight; if positive, proceed to BMI, MNA, SNAQ, and use the “MEALS ON WHEELS” mnemonic to look for treatable causes.

GLIM criteria — malnutrition requires ≥1 phenotypic + ≥1 etiologic criterion:

Severity grading (GLIM Stage 1 vs Stage 2). Stage 1 (moderate): weight loss 5–10% in 6 months or 10–20% beyond 6 months; BMI <20 if <70 y, <22 if ≥70 y; mild–moderate muscle deficit. Stage 2 (severe): weight loss >10% in 6 months or >20% beyond 6 months; BMI <18.5 if <70 y, <20 if ≥70 y; severe muscle deficit.

Caution. Diagnosing malnutrition on low BMI alone, without identifying a cause, overestimates prevalence. Always pair a phenotypic with an etiologic criterion. Nutrition in the Elderly — MD Geriatric Medicine Revision Page 11 of 25 STEP 3 — COMPONENTS OF FULL ASSESSMENT

History. Weight history (magnitude and rate of loss — 5% in 1 month, 7.5% in 3 months, 10% in 6 months is serious), appetite (SNAQ), chewing and swallowing difficulty, dietary history, food fads and restrictive diets, alcohol, drug review (>250 drugs alter taste), depression, dementia, social and financial circumstances, ability to shop and cook, living alone.

Physical examination. General appearance and muscle wasting; oral examination — dentition, ill-fitting dentures, xerostomia, candidiasis, dental plaque, loss of occluding pairs; swallowing test; abdominal exam for faecal impaction; skin for pressure ulcers and poor wound healing; Braden scale for pressure-ulcer risk; signs of specific deficiencies (glossitis, cheilosis, neuropathy, ataxia, ecchymoses, oedema). Pathy’s dental screening tool: dry mouth (2), eating difficulty (1), no dental care within 2 years (1), tooth/mouth pain (2), change in food selection (1), oral lesions (2) — ≥3 points warrants dental referral.

Anthropometry — what each measure reflects (Essentials, Table 3-11):

Practical anthropometric pitfalls and corrections. Serial weight is preferred to BMI — kyphosis makes height unreliable; also consider oedema. Height from knee height: Men = (2.02 × knee height cm) − (0.04 × age) + 64.19; Women = (1.83 × knee height cm) − (0.24 × age) + 84.88. Amputee weight corrections: single below-knee 6%, at knee 9%, above knee 15%, single arm 6.5%, arm below elbow 3.6%. BMI <22 kg/m² predicts higher one-year mortality; BMI below the 15th percentile independently predicts 180-day post-hospitalisation mortality.

Body composition and muscle assessment. DXA (fat-free mass index, appendicular lean mass index), BIA, CT at the L3 slice (muscle index, used in cancer follow-up), MRI. GLIM/sarcopenia cut-offs: FFMI <17 (men), <15 (women) kg/m²; ASMI <7.0 (men), <5.4–5.7 (women) kg/m². Where these are unavailable, calf circumference or MAMC is acceptable.

Functional assessment (increasingly the anchor). Handgrip strength, gait speed, Timed Up and Go, unipodal stance, chair rise, and SPPB (predicts disability). Function correlates with outcome better than mass alone.

Biochemical assessment. Serum albumin — practical, but liver disease, proteinuria and protein-losing enteropathy must be excluded; a normal or raised albumin does not exclude malnutrition. Prealbumin (thyroxine-binding) and retinol-binding protein are more sensitive than albumin and transferrin. Haemoglobin — anaemia is one of the earliest manifestations of protein-calorie malnutrition. Total lymphocyte count — a good marker of nutritional problems. CRP — grades inflammation and separates starvation (CRP <3 mg/L) from cachexia (medium grade) and hypercatabolism (CRP >100 mg/L). Micronutrients: B12 with MMA and homocysteine, folate (red-cell folate reflects the preceding 120 days), 25(OH)D, ferritin with CRP, calcium, TSH. Zinc measurement is unreliable — cytokines lower serum zinc; leukocyte or hair zinc may help. Also: creatinine clearance, blood count, and targeted cancer screening where weight loss is unexplained.

Dietary intake and multidomain assessment. Intake: 24-hour recall, food-frequency questionnaire, food diary, plate-waste/intake charts. Limitations in elders: recall and misclassification bias, worse with cognitive impairment — hence the value of objective nutrient biomarkers. CGA-based assessment (Pathy’s Table 14.3) — cognition (MMSE/MoCA), depression (GDS), delirium (CAM), Nutrition in the Elderly — MD Geriatric Medicine Revision Page 12 of 25 falls (TUG, SPPB), function (Katz, Barthel, Lawton–Brody), morbidity and drug review, nutrition (BMI, MNA, weight history, swallowing, constipation screen, oral exam), and social/socioeconomic domains. Monitoring: weigh nursing-home residents monthly; persistent weight loss must prompt a search for treatable medical, psychiatric and functional conditions.

GLIM — 5-year update. Following review of >400 publications from 2019–2024, no revisions were made to the weight loss, low BMI or reduced food intake/assimilation criteria; assessment of low muscle mass should be guided by experience and available technological resources, and clinical judgement may suffice for the inflammation/disease burden criterion. Severity-grading thresholds are unchanged, but a broad distinction between moderate and severe reduction of muscle mass is not yet possible because only some methods allow that level of differentiation, and further research is needed to secure consensus reference BMI data for Asian populations. (Jensen GL, et al. Clin Nutr / JPEN. 2025.)

Bedside surrogates for muscle mass formally validated. Applying calf circumference <31 cm in both sexes, or MUAC <23 cm in men and <22 cm in women, gave 84.6% and 83.4% accuracy against SGA, with sensitivity ~89% and ~84% and specificity ~81–83%. Directly applicable in Indian wards without DXA or BIA. (Shahraki Jazinaki M, et al.

Choice of tool changes the answer. A meta-analysis of 98 studies (n = 79,976) found a global malnutrition prevalence of 18.6% (95% CI 16.4–21.1%) in older adults, with the highest prevalence — 39.9% — obtained using NRS-2002. Examination point: always state which instrument was used. (Salari N, et al. Public Health in Practice.

Sarcopenia assessment reframed — GLIS 2024. Muscle mass, muscle strength and muscle-specific strength were all accepted as components of sarcopenia, whereas impaired physical performance was accepted as an outcome rather than a component. (Kirk B, et al. Age Ageing. 2024;53:afae052.)

BIA phase angle and BIVA — emerging bedside tools. Phase angle is a highly reliable indicator of skeletal muscle quality because it is calculated directly from reactance and resistance and does not depend on an estimation formula. In hospitalised older patients, standardised phase angle carried prognostic significance and BIVA usefully estimated body-composition/nutrition phenotypes; patients with low standardised phase angle had significantly lower BMI and fat mass. BIVA also discriminated sarcopenic from non-sarcopenic elderly in both sexes, supporting 50 kHz phase-sensitive measurements as biomarkers of hydration, catabolic state and nutritional status. (Front Aging / Clin Nutr cohort studies. 2024–2025; Sensors. 2023;23:7090.)

Muscle ultrasound entering nutritional assessment. In hospitalised older adults, ultrasound and bioelectrical impedance analysis are reliable, non-invasive and reproducible for quantitative and qualitative muscle assessment, with rectus femoris cross-sectional area, thickness, echogenicity and compressibility measured combinedly for sarcopenia diagnosis. (Nutrients. 2024;16:2429.)

ESPEN — screening is mandatory, not optional. All older persons shall routinely be screened for malnutrition in order to identify existing risk early. Low-intake dehydration should be diagnosed on the basis of serum osmolality, not clinical signs alone. A dedicated ESPEN update for dementia followed in 2024. (Volkert D, et al. Clin Nutr. 2022;41:958–989; Volkert D, et al. Clin Nutr. 2024.)

Indian BMI cut-offs need adjustment. CART analysis of LASI data lowered the underweight cut-off from <18.5 to <17.4 for ages 60–74 and <13.3 for those 75 and above, based on cardio-metabolic outcomes. Set against LASI prevalence — 28% of men and 25% of women aged 60 and above are underweight, with those from low economic and social strata more likely to be underweight. (Singh A, Chattopadhyay A. Sci Rep. 2024;14:15200; Khan J, et al. Sci Rep.

Indian dietary reference values for interpreting intake. ICMR-NIN Dietary Guidelines for Indians 2024 with the “My Plate for the Day” model and RDA 2020 (safe protein 0.83 g/kg/day, EAR 0.66 g/kg/day; DIAAS replacing PDCAAS for protein quality). The guidelines discourage protein supplements and high-protein concentrates, citing bone mineral loss and kidney damage with prolonged intake. (ICMR-NIN. Dietary Guidelines for Indians. 2024.)