Malnutrition in Older Adults 

Learning Objectives

Upon completion of this module, students should be able to:

Attitudes

Recognise that poor nutritional status is an often overlooked reversible problem in the care of older adults.

Recognise that undernutrition is frequently a multifactorial problem of complex bio-psycho-social-cultural aetiology.

Knowledge

Discuss age-related physiological changes and psychosocial risks that can predispose to poor nutritional health.

Relate potential complications associated with anorexia, involuntary weight loss (IWL), and protein energy malnutrition for older adults who are: community dwelling, hospitalised, or residents in aged care facilities.

Briefly explain these conditions:  starvation, marasmus, cachexia, kwashiorkor.

Describe the diagnosis and management of protein energy malnutrition (PEM).

Skills 

List medications in which poor nutritional status is commonly an issue. Complete a nutritional status assessment of an older adult in the clinic,

at home, and aged care facility. Recommend appropriate interventions for undernutrition in the clinic,

home, and aged care facility settings.

Module Content: Nutrition, Undernutrition, Malnutrition

I. PrevalenceII. Types of Malnutrition

III. Morbidity and Mortality Impact IV. Normal Ageing ChangesV. Normal RequirementsVI. Contributing Factors

VII. Screening and Assessment

 

I.  PREVALANCE

Geriatric malnutrition is complex and multifactoral.  Additionally, three population subsets need to be considered when one speaks of “older adults”:  community dwelling, hospitalised, and institutionalised in residential aged care settings.

Malnutrition as reduction in nutrient reserve

Ambulatory/Community Dwelling – 1% to 15% Hospitalized – 35% to 65% Institutionalized – 24% to 60

Protein-Energy Malnutrition (PEM):  presence of both clinical and biochemical changes consistent with undernutrition.

Ambulatory/Community Dwelling – 15% Hospitalized – 20% to 65% Institutionalized – 5% to 85%

II.  TYPES OF MALNUTRITION

A. Kwashiorkor-like:  acute or subacute type of PEM that develops acutely or over weeks secondary to physiological stress or low protein intake.  As depletion of visceral proteins (albumin, transferrin, prealbumin and retinol-binding protein) occurs, albumin levels drop, oedema develops and there may not be any weight loss.  The mortality rate is high.  Older adults who already have low serum total cholesterol and serum albumin biochemical markers are at risk for more severe acute illness (even with seemingly minor pathology) due to accentuation of the normal age-related impaired immune response, haematological function, and organ function.  Kwashiorkor may also develop concurrently with the pre-existing marasmus PEM subtype. [mnemonic: Kwashiorkor – Kwick]

B. Marasmus: more insidious development over months to years due to poor food intake.  Muscle wasting (beyond age-related sarcopenia that can be found even in healthy, active older adults) develops in response to the metabolism of skeletal muscle.  Because muscle is metabolised rather than serum or visceral proteins, the serum levels are normal or close to normal.  Mortality is much lower than for kwashiorkor. However, marasmus can quickly develop into a kwashiorkor-like malnutrition during periods of acute illness.   [mnemonic: Marasmus – Muscles; Months]

C. Cachexia:  hypermetabolic state of catabolism and proinflammatory responses (mediated by cytokines such as TNF, IL-1 and IL-6) that occur in both acute, life-threatening illnesses as well as chronic conditions that can elicit an acute-type response.  Examples include cancer, COPD and chronic heart failure.  Anorexia with reduced nutritional intake, fatigue, severe weight loss, increased insulin

resistance, increased CRP, hypercortisolaemia and reduced albumin synthesis can all occur.  Cachexia does not usually respond to hypercaloric intake.  Interventions are aimed at the underlying condition.

D. Starvation: hypometabolic state that occurs due to lack of adequate food intake. Skeletal muscle mass is preserved until late in the starvation course.  Starvation does respond to hypercaloric intake.

E. Undernutrition:  reduction in nutrient reserve

III. MORBIDITY AND MORTALITY IMPACT Inadequate dietary intake can contribute to, or exacerbate disease,

advance age-related degenerative conditions, increase hospital stays and costs, delay illness recovery in outpatients, and increase mortality in older adults compared with older adults who are not nutritionally compromised.

o Specific adverse effects of involuntary weight loss (IWL) in older adults:

Anaemia, Immune dysfunction, Infections, Hip fracture, Pressure Ulcers, Fatigue, Decreased cognitive function, oedema, Muscle loss, Osteoporosis, Falls

NHANES III (National Nutrition Examination Surveys)o Older women (mean age 66) with 5% or more body weight loss

over 10 years had two-fold increased risk of disability compared with women of stable weight

The Geriatric Anorexia Nutrition (GAIN) Registry o Adults living in permanent residential aged care and losing

weight have a higher mortality compared with those who stopped losing weight  [those who lost >5% weight in any one month had a 10-fold increase in risk for death compared with those who gained weight]

o Those who gained weight had a lower mortality than those whose weight loss stabilised.

IV. NORMAL AGEING CHANGES

Reduced bone mass, lean body mass and water content

Increased total body fat and intra-abdominal fat stores (nearly doubled adipose content after age 65)

Physiological Anorexia of Ageingo Weight tends to stabilise until about the 6th or 7th decade, then

slowly declineso Increased circulating cholecystokinin (the satiating hormone)o Reduced relaxation of the fundus allows for quicker passage of

food into the antrum and this antral stretch also contributes to early satiety in older adults

o Reduced BMR (basal metabolic rate) due to muscle mass losses

o BMR is the primary determinant of total energy expenditure

Reductions in olfactory and gustatory (taste and texture discrimination) senses

o Olfactory changes are thought to have a more negative impact on appetite than changes in taste buds

o Mild decrease in saliva production Decreased thirst perception, response to serum osmolality, and ability

to concentrate urine following fluid deprivation

Tendancy to constipation

V. NORMAL REQUIREMENTS

Generally fluid requirements in older adults are roughly estimated to be at least 1500mls/day.  Other formulas are 30-35mls/kg; or, 1500mls the first 20kg + 20ml per additional kg.

A quick estimation of energy based on body weight:  25-30 kcal/kg/day The Harris-Benedict (HB) equation is perhaps the most well-known and

utilised formula for calculating energy needs in hospitalised adults.  It calculates Basal Energy Expenditure (BEE) and then incorporates gender and metabolic stress factors to estimate total energy demands. [Resting Energy Expenditure (REE) is slightly higher than BEE.] Although the equation does not always correctly estimate energy needs, it may be the best available equation at this time.  A study published August 2007 in Clinical Nutrition, (26)4, 498-505 showed that of the 5 best known energy equations, the HB had the lowest mean difference between estimated needs and measured needs (using indirect calorimetry, a metabolic cart, to measure substrate utilisation). The HB equation and stress factors can be found at several websites.  Here is one of them: http://healthlinks.washington.edu/nutrition/section13.html

o Macronutrient Needs Pro – 0.8g/kg/day (1.5 g/kg/day if stress)** Fat – 20% -35% total energy intake per day CHO – 45% - 65% total energy intake per day

Specific conditions may dictate changes; for example:  COPD patients may have less CO2 retention by reducing CHO substrate metabolism and increasing fat calories.  The work of breathing (WOB) in COPD patients can lead to a pulmonary cachexia.

Fibre – 30 g/day (men); 21 g/day (women

**    Sarcopenia is the age-related development and progression of skeletal mass.  The mechanisms of the universal phenomenon are poorly understood.  However, research has suggested that moderate increases of dietary protein greater than 0.8g/kg/day may enhance anabolism and slow skeletal

muscle mass losses with age.  This would not be appropriate in persons with renal disease.  Resistance training also slows sarcopenia and functional decline. Research abstract and full text from the American Journal  of Clinical Nutrition, May 2008, can be accessed online at:   http://www.ajcn.org/cgi/content/full/87/5/1562S

Calcium – recommended daily calcium intake is 1500 mg.

o Ca+ critical to function of cellso 99% of calcium stored in bones /teetho Serum calcium does NOT reflect bone calciumo Ca+ is leeched from bones if needed o 500 mg = Maximum absorbed at one time

Vitamin D – is needed for calcium absorption. Vitamin D synthesis in the skin requires the sun’s UV rays. Sufficient Vitamin D synthesis solely through the sun requires 5-30 minutes of unprotected sun exposure twice weekly. Complete could cover reduces UVB by 50%, shade by 60%, and there is no UVB penetration through glass.

o Community dwelling older adults may be Vitamin D deficient due to sun reduction or avoidance due to skin cancer concerns and subsequent sun avoidance.

o Institutionalised frail older adults are usually sun-deprived and usually require Vitamin D supplementation.

VI.  CONTRIBUTING FACTORS TO UNDERNUTRITION

There are numerous risk factors for nutritional compromise, but it has been reported that the most important are:  low income, social isolation, high stress level, poor appetite, visual impairment, and medical illness. 

1. Poverty and Near-poverty Older women, and older adults living alone or living with non relatives experience poverty rates higher than average.  Poverty rates are higher in rural than in urban older populations.  Since there is a close connection between insufficient income and hunger this suggests many older people are at risk for food insecurity and hunger. 

o Food Insecurity:  “occurs whenever the availability of nutritionally adequate and safe food, or the ability to acquire foods in socially acceptable ways, is limited or uncertain.”

o Hunger:  “uneasy or painful sensation caused by recurrent or involuntary lack of food and is a potential, although not necessary, consequence of food insecurity.  Over time, hunger may result in malnutrition."

o Food Insufficiency:  “an inadequate amount of food intake due to lack of resources.”

2. Functional Deficits:  visual impairments, immobility, tremors, dexterity problems, transportation lack to secure food.

3. Cognitive, Psychiatric & Social:  isolation, lack of transportation, depression, dementia, paranoia.  In nursing homes, depression and other psychiatric conditions account for nearly 60% of involuntary weight loss.

4. Restrictive Diets:  low sodium, low fat, diabetic, renal5. Oral Problems:  edentulous, poor fitting dentures, dental

pain, oral sores, xerostomia (due to medications, Sjogren’s disease), dysgeusia

6. Medical Conditions:  COPD, cardiac disease, dysphagias, Parkinsonism and other neurological disorders, cancer, arthritis, infections, thyroid disorder, malabsorption syndromes, GORD, alcoholism, and others.

7. Polypharmacy as well as specific Offending Drugs:  Many medications have side-effects that can negatively impact nutrition directly or indirectly, and eventually lead to weight loss.  The following potential effects and associated medications are only a few examples:

Anorexia – digoxin, spironolactone, furosemide, phenytoin, K+ supplementsNausea – digoxin, NSAIDs, opioids, some antibioticsAltered taste – metronidazole, clarithromycin, ACEIs, CCBs, metforminDysphagia – bisphosphonates, NSAIDs, K+ supplements Early satiety –anticholinergicsHypermetabolism – thyroxine                Constipation  --  opioids, iron, diureticsDiarrhea – antibiotics

Also consider the potential risk for free circulating drug in undernourished persons taking medications that are highly protein bound such as digoxin.

VII.  SCREENING AND ASSESSMENT

A. Screening

Nutritional screening tools are general survey, questionnaire, checklist or scaled instruments to identify individuals in a group of older adults with undernutrition or at potential risk. They can be self-administered, volunteer or professionally administered.  Screenings may lead to individual nutritional assessments to diagnose and treat persons with undernutrition.  Seven criteria have been established for screening tool selection: 1) simple– easy to use and interpret; 2) acceptable to the older adult; 3) accurate 4) cost – benefits equal to or exceed cost; 5) reliable; 6) sensitive; and 7) specific.

The Nutrition Screening Initiative (NSI) was developed to address the prevalence of malnutrition among older adults; it was a collaborative effort among the AAFP (American Academy of Family Physicians), the ADA (American Dietetic Association), and others.  Two of the tools cited below (DETERMINE and NMA)  were among the many outcomes of the NSI.

1. DETERMINE: a checklist of warning signs of poor nutrition. 

DiseaseEating PoorlyTooth Loss/Mouth PainEconomic HardshipReduced Social ContactMultiple MedicationsInvoluntary Weight Loss / GainNeeds self-care assistanceEighty years old or over

The questions in the screening tool flow out of the DETERMINE warning sign mnemonic above.  The questionnaire and scoring criteria can be found at: http://geridoc.net/nutrition.html  or nutritionandaging.fiu.edu/downloads/NSI_checklist.pdf

2. MNA:  Mini-Nutritional Assessment is both a screening and assessment tool.  The MNA-SF (short form) is only a screen and is Part I of the two-part MNA tool.  The MNA has been called the best screening tool for use in older adults.  More detailed Information and the tool itself can be viewed at:  http://www.merck.com/media/mmpe/pdf/Figure_002-1.pdf

http://www.mna-elderly.com/forms/mna_guide_english.pdf  (color detailed MNA directions)

3. SCALES:  this tool has been cross-screened with the MNA and is useful in outpatient settings.  Available online at: http://www.merck.com/mrkshared/mmg/tables/61t3.jsp

B. Assessment

1. Detailed History and Exam o Diet and weight history, Medical, Medications,

Psychiatric, Social (financial resources, bereavement, isolation, alcohol), Functional

o Potentially Reversible Causes? Meals on Wheels mnemonic in residential

aged care

MedicationsEmotional (depression)Alcoholism/ Anorexia tardive (late life nervosa)Late onset paranoia Swallowing disorders

Oral problemsNosocomial infections (H. pylori, C. Diff)

Wandering (& other dementia related behavior [DRB] )Hyperthyroidism / Hypoadrenalism / HypercalcemiaEnteric problems (malabsorption)Eating ProblemsLow salt dietStones (cholelithiasis)

2. Clinical Signs of Undernutrition o Muscle wasting, loss of fat storeso Percentage of IWL (involuntary weight loss)

5% in 30 days 10% in 6 months or less

o BMI < 21 [severe if <19]o Weight < 80% IBW (ideal body weight) o Anthropometrics

Mid-arm circumference and Triceps skin fold measurements

< 10th percentile on normative values table May yield more useful information over time

using the patient as his/her own control Not commonly done unless part of Nutrition

Support Team or Registered Dietician Consult

o Clinical signs of Dehydration Reduced urine output New or worsened orthostatic vital signs Delirium Xerostomia

“Ropey” saliva Buccal mucosal dryness Dry, furrowed tongue Caution:  patients with Sjogren’s

disease often have xerostomia as well as dryness of other mucous membranes (depending on severity)

3. Biochemical Signs of Undernutrition o Low Total Cholesterol (TC) [late sign]o Serum Albumin < 35

half-life 2-3weekso The combination of BOTH low total cholesterol and

serum albumin confers even greater risk of increased morbidity or mortality.

Low Albumin has prognostic significance but is not sensitive nor specific  for malnutrition; it may actually be a marker of inflammatory status due to cytokine activity

o Other testing that may be useful in searching for potentially reversible underlying causes:  FBC, TFT, FOBs (faecal occult blood)

C. Treatment

1. Address the underlying cause when possible o Example:  treat the pain of arthritic hands (or any

significant pain), depressive pathology, GORD, tremor, dental appliance fit, oral topical analgesics, drug contributions, artificial saliva, etc

o Obtain dietician consult o Estimate energy requirementso Eliminate restrictive diets

Involve patient in food preferences Use calorie dense foods

2. Liquid Supplements between meals o Recall that supplements usually do not work in

cachexias (hypermetabolic states) o Little benefit if given with meals

3. Smaller portions & more frequent eating rather than traditional 3 meals

Consider disease specific recommendations in select cases, such as switching substrate to low carbohydrate (CHO) and higher balanced-fat calories in patients with COPD.  CHO substrate metabolism typically results in increased CO2 production which can be burdensome on the lungs to try to exhale it.  The Respiratory Quotient (RQ) is a ratio of C02 production to O2 consumption.  The RQ for CHO metabolism is higher than that for fat or protein.  Commercially available low CHO and balanced

high-fat nutritional supplements are available for patients with COPD.  These types of products may be helpful in COPD patients who are hypercapnaeic.  They also provide denser calories which is usually beneficial in persons with COPD since the work of breathing (WOB) alone can be very costly in terms of caloric expenditures.  Low BMI in patients with COPD is associated with higher mortality. 

4. Consult a speech pathologist for evaluation and management recommendations regarding dysphagia in any one or more of the four phases of deglutition.

5. Carefully consider Orexigenic Drugs (so-called appetite stimulants)

o Antidepressant Mirtazapine:  antidepressant with some

orexigenic properties. Sedating.  Start with low dose 15mg. Give at bedtime. 

o Anabolic Steroid Testosterone:  Low levels correlate with

male sarcopenia.  May be reasonable in undernourished men with low testosterone levels.  Not commonly tried.

o Progestational Agent Megestrol Acetate:  (Megace ®) 400 to 800

mg increases appetite (food intake) and weight.  Weight gain is fat.  Risks:  DVT, markedly decreased testosterone levels, adrenal suppression, edema, constipation, hyperglycemia.  Use in ambulatory persons with cytokine excess.  If used in men, may consider use concurrently with testosterone.

o Prokinetic Agent Domperidone:  useful if gastroparesis and

nausea limit oral intakeo Glucocorticoids – e.g. dexamethasone- but side

effects limit use

6. Nutrition Tubes o commonly called “feeding tubes” although there is

nothing about these tubes that is “feeding.”  The term “feeding” carries heavy emotional and social connotations.  Rather, these are medical devices used for a medical treatment that allows for an alternative provision of nutrition (aka: artificial nutrition).

o May be appropriate in dysphagia given the patient’s full medical context and QOL (quality of life), especailly if some degree of recovery is expected (e.g following stroke)

o They are not recommended in end-stage dementia (studies show no benefit)

o They are not appropriate if the primary purpose is to prevent aspiration pneumonia as there is no research demonstrating PEG (percutaneous endoscopic gastrostomy) tubes prevent pneumonia