Geriatric Failure to Thrive

Geriatric failure to thrive is a syndrome of unintentional weight loss, poor appetite, inadequate nutrition and physical inactivity, often with decline in cognition and function. Unintentional loss of more than 5% of body weight in a month or more than 10% in 6 months is a commonly used marker.

It is common in frail people, in hospital and in nursing homes.

Pathophysiology. The cause is multifactorial. Anorexia of ageing, depression, dementia, dysphagia, poor dentition, medicines, social isolation, poverty, chronic disease and occult malignancy each reduce intake or raise energy needs. Inflammation then drives catabolism and muscle loss.

Weight loss, low appetite, reduced food intake, low body mass index (under 18.5 kg/m2), weakness, fatigue, falls, pressure injury, infections and loss of independence. Cognitive decline and low mood often coexist.

Red flags.

• Rapid weight loss with night sweats, fever or lymphadenopathy.
• Dysphagia, vomiting, melaena or change in bowel habit.
• Cough with haemoptysis or breathlessness.

Document the weight trend and screen with a validated nutrition tool. Assess mood, cognition, swallowing, dentition and medicines. Investigate with full blood count, C-reactive protein, urea and electrolytes, glucose, thyroid function, calcium, liver tests, vitamin B12, folate, coeliac serology, urinalysis and chest radiograph. Add HIV testing, faecal occult blood or imaging when the picture suggests it.

Differential diagnosis.

• Malignancy, tuberculosis and other chronic infection.
• Hyperthyroidism, diabetes mellitus, adrenal insufficiency and hypercalcaemia.
• Heart failure, COPD and chronic kidney disease.
• Malabsorption, coeliac disease and chronic mesenteric ischaemia.
• Depression and dementia.

Treat reversible causes first. Relax dietary restrictions, fortify meals, offer small frequent meals and oral nutritional supplements, and provide help with eating. Repair dentition and treat dysphagia. Stop drugs that reduce appetite (digoxin excess, metformin, cholinesterase inhibitors where tolerated badly, opioids). Treat depression; mirtazapine 7.5 to 15 mg at night may help depression with poor appetite. Avoid megestrol because of thromboembolism and mortality risk. Tube feeding gives no survival or comfort benefit in advanced dementia.

Monitoring. Weigh weekly at first, then monthly.

Referral and escalation. Refer for dietetic and speech and language therapy assessment, and for investigation of suspected malignancy. Hold goals-of-care discussions when decline continues despite treatment.