Gastro - Disorders of Appetite Flashcards
What is polydipsia?
excessive thirst or excess drinking
What is adipsia?
inappropriate lack of thirst
- with consequent failure to drink in order to correct hyperosmolality
What is the clinical definition of anorexia as a symptom?
lack or loss of appetite for food
What is obesity?
abnormal or excessive fat accumulation that presents a risk to health
What are the 2 different types of polydipsic or adipsic?
primary or secondary
What is secondary polydipsia?
Medical issues that disrupt any step in osmoregulation or alter ADH
Which type of polydipsia is more common?
secondary
What are the 3 main categories of causes of secondary polydipsia?
→ chronic medical conditions
→ medications
→ dehydration
What are the chronic medical conditions that causes secondary polydipsia?
→ Diabetes insipidus & mellitus
→ Kidney failure
→ Conn’s syndrome
→ Addison’s disease
→ Sickle cell anaemia
What medications can cause secondary polydipsia?
→ Diuretics
→ Laxatives
(Both result in dehydration)
→ Antidepressants
What can cause dehydration generally, which can go to cause polydipsia?
→ Acute illness
→ Sweating
→ Fevers
→ Vomiting
→ Diarrhoea
→ Underhydration
What are the key differences between diabetes mellitus and diabetes insipidus?
What are the common symptoms of diabetes?
→ always tired
→ always hungry
→ frequent urination
→ blurry vision
→ numb or tingling hands + feet
→ always thirsty
→ sudden weight loss
→ wounds that won’t heal
→ sexual problems
→ vaginal infections
How does acute kidney failure lead to polydipsia?
→ the failing kidneys lose the capacity to concentrate the urine maximally
→ which means that they must excrete more water to eliminate the solutes acquired in the diet
→ As a consequence, patients are forced by thirst to drink more water to cover the loss linked to solute excretion
How does Conn’s syndrome cause polydipsia?
v
How does Addison’s disease cause polydipsia?
v
What can cause primary polydipsia?
→ Mental illnesses - psychogenic polydipsia
→ Brain injuries
→ Organic brain damage
What other mental illnesses can cause primary polydipsia?
→ schizophrenia
→ mood disorders (depression + anxiety)
→ anorexia
→ drug use
What are the consequences of polydipsia?
→ Kidney and bone damage
→ Headache
→ Nausea
→ Cramps
→ Slow reflexes
→ Slurred speech
→ Low energy
→ Confusion
→ Seizures
What are the different types of polydipsia? What is most common?
→ Type A – most common
→ Type B
→ Type C
→ Type D
What is the mechanism of adipsia?
→ increased osmolality of urine
→ stimulates secretion of ADH
→ water retention
→ sensation of thirst decreases
What is an eating disorder?
mental illness defined by abnormal eating habits
What are some examples of eating disorders?
→ Binge eating disorder
→ Anorexia nervosa
→ Bulimia nervosa
→ Pica (eating or craving of things that are not food)
→ Rumination syndrome (rare behavioral disorder in which food is brought back up from the stomach. It is either rechewed, reswallowed, or spit out)
→ Avoidant/restrictive food intake disorder (restricted to eating 1 or 2 types of food, to necessarily to do with body image)
What is the prevalence of eating disorders?
→ Global eating disorder prevalence increased from 3.4% to 7.8% between 2000 and 2018
→ 70 million people live with eating disorder
What are the signs of anorexia?
→ low BMI
→ continuous weight loss
→ amenorrhea
→ halitosis
→ mood swings
→ dry hair + skin
→ hair thinning
What are the causes of anorexia?
→ genetics
→ environmental
→ psychological
→ sociological
What is the main mechanism of anorexia?
→ something to do with serotonin
→ mainly unsure
What BMI signifies mild anorexia?
BMI > 17
What BMI signifies moderate anorexia?
BMI of 16-16.99
What BMI signifies severe anorexia?
BMI of 15-15.99
What BMI signifies extreme anorexia?
BMI < 15
Why is obesity increasing?
→ not down to lack of exercise (physical activity started to decline prior to obesity epidemic)
→ cheap calorie-rich / nutrient poor beverages, sweets + fast food
How do you screen for obesity?
→ Height, weight and abdominal girth
→ Medical history: Dietary and physical activity patterns, psychosocial factors, weight-gaining medications, familial traits
→ BMI of ≥30 or ≥25 + comorbidity or risk factor
What life-style modification is best in treatment of obesity?
→ diet = 8.5%
→ exercise = 2.4%
→ diet + exercise = 10.8%
therefore both work best
When are people referred to surgical treatment of obesity?
people with > BMI 40 or
people with > BMI 35 and have co-morbidities
What are the different surgical treatments for obesity?
→ bariatric surgery = weight-loss surgery
→ various procedures
→ most common = Roux-en-Y gastric bypass & sleeve gastrectomy
What are the effects of bariatric surgery?
→ WL 5 yrs after BS: 30% - 35%
→ Remission of comorbidities:
→ Diabetes (80%)
→ OSA (80%-85%)
→ reduction of mortality and morbidity after BS
What are the effects of GLP-1 and GLP-2?
→ stimulate insulin release
→ inhibit glucagon release
What are the hormonal changes after BS?
→ reduction of ghrelin
→ elevation of GLP-1 + GLP-2 + PYY
