The reasons for unintentional weight loss
Unintentional weight loss usually develops over weeks or months. This can be a sign of significant physical or mental impairment and is associated with an increased risk of mortality. The cause of the illness may be obvious (eg chronic diarrhoea due to malabsorption syndrome ) or unknown aetiology (eg undiagnosed cancer). The reasons for unintentional weight loss doing unintentional weight loss this discussion concerns patients who are losing weight rather than those who are losing weight due to a more or less expected consequence of a known chronic disease (eg, metastatic cancer, end-stage chronic obstructive pulmonary disease [COPD]).
Do unintentional weight loss is generally considered a clinically significant symptom if it exceeds 5% of body weight or 5 kg in 6 months. However, this traditional definition does not distinguish between the loss of both muscle and fat mass, which can lead to different results. In addition, oedema (for example, in heart failure or chronic kidney disease ) can mask clinically significant muscle loss.
In addition to weight loss.
Patients may have other symptoms.
Such as anorexia, fever, or night sweats caused by the underlying medical condition.
Symptoms and signs of nutritional deficiencies may also be present.
Depending on the cause and its severity (see Vitamin Deficiency, Metabolic Disorders and Overdose ).
The overall incidence of significant involuntary weight loss in the United States is about 5% per year.
However, the incidence increases with age.
Often reaching 50% among patients in nursing centres.
Weight loss results are caused by the higher calories burned compared to the calories consumed (consumed with food and absorbed).
Diseases that increase flow or decrease absorption tend to cause an increase in appetite.
But the reasons for unintentional weight loss.
More often than not.
Then the inadequate caloric intake is a mechanism for weight loss.
Such patients tend to experience decreased appetite.
Several mechanisms are sometimes involved.
For example, cancer leads to a decrease in appetite but also increases the main calorie expenditure due to the action of cytokinin mechanisms.
Many diseases cause involuntary weight loss.
Including almost any chronic disease of sufficient severity.
However, many of them are clinically evident and were usually diagnosed at the time of weight loss.
Other disorders are most likely to manifest as involuntary weight loss (see table Some Causes of Primary Symptoms of Involuntary Weight Loss ).
The most common causes of involuntary weight loss of unknown aetiology are associated with increased appetite, such as
- Uncompensated diabetes mellitus
- Diseases causing malabsorption
The most common causes of involuntary weight loss of unknown aetiology are associated with the decreased appetite to such as
- Mental illness (such as depression )
- Side effects of medications
- Drug abuse
For some conditions that cause involuntary weight loss to other symptoms are more prominent.
Then the so weight loss is usually not the main complaint.
Examples include the following:
- Some malabsorption disorders: gastrointestinal surgery and cystic fibrosis
- Chronic inflammatory diseases: severe rheumatoid arthritis
- Diseases of the gastrointestinal tract: achalasia, celiac disease, Crohn’s disease, chronic pancreatitis, obstructive oesophagal disease, ischemic colitis, diabetic enteropathy, peptic ulcer disease, progressive systemic sclerosis, ulcerative colitis (end-stage)
- Severe chronic diseases of the lungs and heart: chronic obstructive pulmonary disease (COPD), heart failure (stage III or IV), pulmonary fibrosis
- Mental illnesses (known and poorly controlled): anxiety, bipolar disorder, depression, schizophrenia
- Neurological diseases: amyotrophic lateral sclerosis, dementia, multiple sclerosis, myasthenia gravis, Parkinson’s disease, stroke
- Social issues: poverty, social exclusion
In chronic kidney disease and heart failure to swelling can mask the loss of muscle mass.
The survey should focus on identifying other unknown causes of the disease.
Due to the fact that these reasons are numerous, the survey should be comprehensive.
The history of present illness includes questions about quantitative weight loss and its dynamics.
Weight loss reports may not be accurate.
Thus, corroborating evidence should be sought.
For example, in weight measurements in old medical records.
But changes in clothing size or confirmation from family members.
Appetite, doing unintentional weight loss eating and swallowing.
And bowel imaging should be described.
On follow-up examinations to patients should keep a food diary because food recollections are often inaccurate.
Then nonspecific symptoms of possible causes are noted.
Then such as feeling tired.
Feeling unwell, fever, and night sweats.
A systemic review should be complete.
Considering symptoms for all major organ systems.
Medical history can reveal conditions that can cause weight loss.
The issues of the need to use prescription drugs.
Nonprescription drugs to soft drugs and herbal medicines are also considered.
Social history can reveal changes in life situations that could explain why food intake is declining (eg, loss of a loved one, loss of independence or work, loss of common eating habits).
Vital signs are checked for fever, tachycardia, tachypnea, and hypotension.
The weight is measured and the body mass index is calculated (see Obesity: diagnosis ).
To assess muscle mass, triceps skinfold thickness and average arm circumference can be measured (see Review of Malnutrition: Physical Examination ).
BMI and lean body mass scores are useful mainly for detecting dynamics at follow-up visits.
General examination should be especially complete.
But including examination of the heart, lungs, abdominal organs, head and neck, mammary glands, nervous system, rectum (including examination of the prostate and occult blood test), genitals, liver, spleen, lymph nodes, joints, skin, mood and emotional responses.
Fever, night sweats, generalized lymphadenopathy
Shortness of breath, cough, hemoptysis
Inappropriate fear of weight gain in adolescent girls or young women
Polydipsia and polyuria
Headache, chronic dislocation of the mandible and/or visual impairment in the elderly
Roth spots, Janeway sores, Osler’s nodes, haemorrhages at the base of the nails, retinal artery embolism
Interpretations of some results are shown in the table Interpretation of individual results for involuntary weight loss.
Abnormal results suggest a cause for weight loss in about half or more of patients.
Including those ultimately diagnosed with cancer.
Although many chronic illnesses can lead to weight loss.
The doctor should not rush to assume that existing medical conditions are causing it.
Although an existing condition is a likely cause of weight loss in patients whose condition remains poorly controlled or worsening.
But stable patients who suddenly begin to lose weight without worsening the course of the disease may be diagnosed with new diseases.
(for example, patients with stable ulcerative colitis may begin to lose weight because they have developed colon cancer).
Age-appropriate cancer screening tests (eg, colonoscopy, mammography) are indicated if not previously performed.
Other research is done when treating diseases that are suspected based on a history of abnormal findings or on examination.
According to one of the proposed approaches the following tests should be done:
General urine analysis
Complete blood count (CBC) with the determination of the leukocyte formula
Erythrocyte sedimentation rate (ESR) or C-reactive protein
Biochemical analysis (serum electrolyte and calcium levels, liver and kidney function tests)
Serum thyrestimulating hormone (TSH)
As shown the pathological results of these studies follow from additional analyzes.
If all test results are within normal limits.
And the clinical data are normal.
Such testing is very ineffective and can be misleading and harmful.
But showing random or unrelated data.
But such to patients should be trained inadequate caloric intake.
And followed up after about 1 month with body weight measurements.
If patients continue to lose weight.
The entire history and physical examination results should be reviewed.
Because patients may share important.
But previously undisclosed information and new, weak physical pathologies may be discovered.
If weight loss continues, and all other indicators remain within the normal range.
Then the purpose of further studies (for example, CT, MRI) should be considered.
Treatment of the underlying disease is necessary.
If the underlying condition is to associated with malnutrition.
It should be to considered the appointment power supply.
Useful general behavioural interventions include motivating patients to eat by helping them eat.
But offering snacks between meals and before bedtime.
Providing favourite foods or foods with strong flavours.
Then offering only small portions.
If behavioural interventions are ineffective and weight loss is extreme.
But appetite stimulants are not indicated to prolong life.
Important points in geriatrics
Normal age-related changes that can contribute to weight loss include the following:
Desensitization to certain appetite stimulant mediators (eg, orexins, ghrelin, neuropeptide Y) and increased sensitivity to
certain inhibitory mediators (eg, cholecystokinin, serotonin, corticotropin-releasing factor)
Decreased rate of gastric emptying (prolonged satiety)
Decreased taste and olfactory sensitivity
Loss of muscle mass (sarcopenia)
In older people to numerous chronic illnesses often contribute to weight loss.
Social isolation causes a downward trend in food intake.
In particular patients in nursing care centres but depression is a common factor.
It is so difficult to isolate the exact contribution of individual factors due to interactions between factors such as depression.
loss of function, drug effects, dysphagia, dementia, and social isolation.
When evaluating elderly patients with weight loss.
A checklist of potential contributing factors starting with the letter D is helpful:
Medical conditions (such as severe kidney, heart, or lung disease)
Perversion of taste
- Elderly patients with weight loss should be screened for vitamin D deficiency
- vitamin B12 deficiency.
Enteral feeding is rarely beneficial for elderly patients.
Except in isolated patients in whom this type of feeding may be a short-term transition period to a normal diet.