What is the primary recommendation for managing Protein-Energy Malnutrition (PEM) in adults?

Management of Protein-Energy Malnutrition (PEM) in Adults

The primary recommendation for managing PEM in adults is to provide 30 kcal/kg/day energy intake and 1.2-1.5 g/kg/day protein intake, starting with dietary counseling and food fortification, followed by oral nutritional supplements (ONS) providing at least 400 kcal/day with ≥30g protein/day if dietary measures alone are insufficient. 1, 2

Initial Assessment and Energy-Protein Targets

Target 30 kcal/kg body weight per day for energy requirements in malnourished adults. 1 This energy prescription should be individualized based on age, sex, physical activity level, body composition, and presence of concurrent illness or inflammation. 3

Prescribe protein intake of 1.2-1.5 g/kg body weight per day to promote muscle protein anabolism and prevent further fat-free mass loss. 1, 4 This higher protein target compared to healthy adults addresses the anabolic resistance commonly seen in malnourished individuals. 3, 2

Stepwise Nutritional Intervention Algorithm

Step 1: Dietary Counseling and Food Fortification

• Begin with intensive dietary counseling and food fortification techniques to increase energy and protein density of regular foods without increasing volume. 1, 2
• Offer small, frequent meals with additional snacks between main meals to increase total daily intake. 1
• Provide texture-modified, enriched foods for patients with chewing or swallowing difficulties. 1, 2
• Create a pleasant meal environment with social interaction to stimulate appetite and improve intake. 1, 2

Step 2: Oral Nutritional Supplements (ONS)

When dietary counseling and food fortification fail to achieve adequate intake, prescribe ONS providing at least 400 kcal/day including 30g or more of protein per day. 1, 2 Continue ONS for a minimum of one month (or three months in CKD patients) with regular efficacy assessment. 3, 2

ONS have been shown to improve dietary intake, body weight, and lower risk of complications and readmission in hospitalized patients. 2, 5

Step 3: Enteral Nutrition

For patients with chronically inadequate intake whose requirements cannot be met by dietary counseling and ONS, consider a trial of enteral tube feeding. 3

Step 4: Parenteral Nutrition

In adults with PEM whose nutritional requirements cannot be met with oral and enteral intake, initiate total parenteral nutrition (TPN). 3 For hemodialysis patients specifically, intradialytic parenteral nutrition (IDPN) is an alternative option. 3

Pharmacological Appetite Stimulation

For elderly patients with moderate to severe PEM and poor appetite despite nutritional interventions, mirtazapine 7.5-15 mg at bedtime is the first-line pharmacological appetite stimulant. 2 Use lower starting doses in elderly patients with close monitoring for sedation. 2

Megestrol acetate 400-800 mg/day may be considered as second-line if mirtazapine is ineffective or contraindicated, though it carries increased risk of death (RR 1.42) and thromboembolic events (RR 1.84). 2, 6

Dexamethasone 2-8 mg/day is reserved as third-line for patients with shorter life expectancy, given significant side effects including hyperglycemia, muscle wasting, and immunosuppression. 2

Special Population Considerations

Chronic Kidney Disease (CKD)

• For CKD stages 1-5 not on dialysis: prescribe 0.6-0.8 g/kg/day protein to maintain stable nutritional status. 3
• For hemodialysis or peritoneal dialysis patients: increase to 1.0-1.2 g/kg/day protein. 3
• Energy intake should remain 25-35 kcal/kg/day based on individual factors. 3

Diabetes with Malnutrition

For older adults with diabetes and malnutrition, follow the same guidelines as non-diabetic adults—prevention and treatment of malnutrition takes priority over possible long-term complications of hyperglycemia. 1 In patients with insulin resistance, increase the ratio of fat to carbohydrate calories to increase energy density and reduce glycemic load. 1

Pressure Ulcers

For malnourished patients with pressure ulcers, consider supplementation with formulas enriched with arginine, zinc, and antioxidants to improve healing. 1

Critical Pitfalls to Avoid

Do not use hypoalbuminemia as the sole marker for protein malnutrition, as it is affected by inflammation and other non-nutritional factors. 4 Prealbumin is more sensitive for tracking nutritional repletion. 4

Avoid restrictive diets that limit dietary intake—these are potentially harmful and can worsen malnutrition. 1 Do not restrict energy intake even in obese patients with malnutrition. 1

Do not delay nutritional intervention until severe malnutrition develops—early intervention is more effective. 1

Avoid appetite stimulants in patients with dementia without evidence of depression. 2

Refeeding Syndrome Prevention

In severely malnourished individuals, start nutritional support early but increase gradually during the first three days to prevent refeeding syndrome. 1 Monitor blood levels of phosphate, magnesium, potassium, and thiamine during the first three days and supplement even with mild deficiency. 1

Multimodal Approach

Combine nutritional interventions with physical activity and exercise to maintain or improve muscle mass and function. 1 Screen for and address nutrition impact symptoms that impair food intake. 1 Regular assessment of nutritional status with adjustment of interventions based on response is essential. 1