Course:PostgradFamilyPractice/ExamPrep/99 Priority Topics/LOW

From UBC Wiki

Loss of Weight - Key Features

1. Pursue an underlying cause in a patient with unexplained weight loss through history, physical examination (including weight) and appropriate investigations.

2. Maintain an ongoing record of patients’ weights so as to accurately determine when true weight loss has occurred.

3. In patients with persistent weight loss of undiagnosed cause, follow-up and reevaluate in a timely manner in order to decide whether anything needs to be done.

Look out!! Involuntary weight loss, either with decreased or increased appetite, is nearly always a sign of a serious medical or psychiatric illness

History: magnitude of the loss of weight loss?

- Clinically significant weight loss is 10 lbs or more, or 5 % of baseline body weight over 6-12 months
- Get their past history – from family members, i.e.: changes in eating habits, old growth charts,
- Previous variations in weight during adult life?
- Voluntary or involuntary weight loss?
- Appetite ↑ or ↓?
- Time course of weight loss?
- Diabetic - weight loss and increased appetite indicator of poor diabetic control
- Type 1 diabetes (ask especially in young patients) may purposely decrease their insulin dose in an attempt to lose weight
- Recent changes to medications
- Herbal products

Differential Diagnosis
Involuntary weight loss with ↑’d appetite

- Hyperthyroidism, uncontrolled diabetes mellitus, malabsorption syndromes, pheochromocytoma,
- Marked ↑ in physical activity (relatively fewer causes of weight loss with ↑’d appetite – it’s either increase caloric expenditure or loss via the gut/kidneys)
- Hyperthyroid elderly patients may manifest anorexia (apathetic hyperthyroidism) rather than ↑’d appetite

Involuntary weight loss with ↓’d appetite

- Medical disorders, malignancy, endocrinopathies, chronic illness, COPD, GI disease, psych d/o (depression, manic phase, etc.), chronic drug use, alcohol, opiates, amphetamines/cocaine, other meds topiramate and zonisamide, SSRI, levodopa, digoxin, metformin, NSAID’s drugs, anticancer drugs)
- Cancer anorexia-cachexia syndrome – weight loss due to cancer occasionally is the only manifestation of cancer
- HIV infection - Muscle wasting and weight loss are common in patients with HIV
- Endocrinopathies – Hyperthyroidism
- Adrenal insufficiency
- Hypercalcemia
- Diabetes
- Cardiac cachexia – weight loss in a patient with advanced congestive heart failure and COPD
- GI diseases - weight loss with loss of appetite occurs either directly or indirectly by:
• Dysphagia
• Sensation of satiety
• Vomiting and regurgitation
• Abdominal pain or discomfort
• Chronic inflammation
• Malabsorption
• Spontaneous and surgical fistulas and bypasses
- Herbal products

Voluntary weight loss/ intentional ↓’d food intake

- Treatment of obesity, intentional use of anorexic drugs – amphetamines and derivatives, anorexia nervosa and bulimia, distance runners, models, ballet dancers, gymnasts
- Psych: bipolar illness during manic phase, depression, Munchausen syndrome – as a mechanism for getting attention, delusional/paranoid disorders – ideations about food, neuroleptic withdrawal cachexia (chlorpromazine, thioridazine, haloperidol), cannabis withdrawal syndrome (sudden discontinuation of the “munchies”)

Possible CCFP Key Features:
1. Involuntary weight loss often indication of a serious underlying medical/psychiatric condition (i.e. cancer).
2. Determining if there is an increase or decreased appetite can help differentiate a cause.
3. Various chronic diseases (Cardiac, Endocrine, GI, Pulmonary, Infectious, Psych) can often lead to weight loss by different mechanisms.
4. A review of medications is essential since the use of some medications or the withdrawal of others can cause involuntary weight loss.
5. There are relatively fewer causes of involuntary weight loss with ↑’d appetite compared to ↓’d appetite. Appetite increases when either there is an increase in caloric expenditure or there’s a loss, i.e. via GI/kidneys
6. Obese patients may exaggerate weight loss and patients with underlying organic cause may try to minimize the weight loss.

Study Guide

Loss of Weight