Transcription
Obesity is defined as excess fat with many associated comorbidities. It is associated with a significant increase in mortality, including a reduced life expectancy of up to 10 years.
The body mass index, or BMI, is the accepted standard measure of obesity and weight. The BMI is represented by kilograms per meter squared. Being underweight has a BMI of less than 18.5. A normal BMI is 18.5 to 24.9. Overweight is 25 to 29.9, and obesity is greater than 30, which is then further divided into three different classes.
Another measurement of obesity is waist circumference, which takes into account central adiposity and really has a better correlation to cardiovascular disease. Obesity is defined when the waist circumference in men is greater than 102 centimeters, or greater than 40 inches. In women, it's greater than 85 centimeters, or 35 inches. The waist circumference is measured at the level of the iliac crest.
Obesity is complex, and the pathophysiology involves genetics and behavioral habits. There is energy intake versus energy expenditure, as well as changes in the neuroendocrine pathways. But to put it simply, really, obesity occurs when you have increased energy intake but reduced expenditure, and so all this accumulation of energy just goes into fat deposits around the body.
The etiologies and risk factors of obesity. It can be divided into behavioral things, such as physical inactivity, poor diet, such as high, you know, takeaway foods, also cessation of smoking because people take up other habits such as eating more. Further poor eating patterns, such as overeating, binge eating, or night eating, is associated with increased energy intake. Sleep deprivation is also a risk factor.
There are many medical causes of obesity. These include hypothalamic obesity, caused by damage to the hypothalamus, a part of the brain that makes hormones that control specific body functions, such as sleep, as well as hunger. Growth hormone deficiency, hypothyroidism, low thyroid levels released from the thyroid gland, hypogonadism in women, polycystic ovarian syndrome, which is also associated with hirsutism. Cushing's syndrome is a very important medical cause, and really, patients manifest with elevated cortisol levels, and you could get moon-like faces and a buffalo hump.
There are many medications that can cause an increase in weight. These include, namely, corticosteroids, which really lead to Cushing's appearance and stimulates appetite, so you eat more. Antipsychotics, antidepressants, beta-blockers. There are also anti-diabetic agents, such as insulin, which causes mild weight gain, as well as sulfonylureas.
Complications of obesity is a lot, and these include stroke, the stigma associated with being obese, respiratory issues such as obstructive sleep apnea, obesity hypoventilation syndrome, which is really characterized when you have slightly increased amounts of carbon dioxide in the body, gastroesophageal reflux disease, heart diseases including heart attacks, hypertension, hyperlipidemia, a fatty liver disease, diabetes, urinary incontinence, osteoarthritis from all the weight, increased risk of gout, venous thrombosis, hernias, as well as an increased risk of certain malignancies as well.
To know something called metabolic syndrome, which is really encompasses obesity as well. Metabolic syndrome describes a constellation of medical conditions which increases the risk of cardiovascular disease. These conditions include insulin resistance, hypertension, hyperlipidemia, and obesity. All this makes up metabolic syndrome.
The treatments for obesity. Well, there's many approaches, but first is to address the underlying cause if it's medical or behavioral, as well as addressing the triggers. You want to set a realistic goal, for example, five percent body weight reduction per year. And a good idea is to create an action plan involving a certain diet, such as a low-calorie diet, an exercise program.
Pharmacotherapy, or medications, also have a role in the treatment of obesity, usually when all other things fail. These pharmacotherapies include a GLP-1 agonist. Now, a GLP-1 is a normal peptide that's produced by the body, which slows gastric, which slows gastric emptying, inhibits glucagon excretion, and stimulates insulin production. The side effects of this include nausea and vomiting. Further, GLP-1 agonists are given as an injection into the tummy or the thigh, and so this could also be a sort of a side effect in a way.
Orlistat is another medication that works on the pancreas by inhibiting the pancreatic lipase. Lipase is an enzyme which helps break down fat so that fat can be absorbed by the body. By inhibiting, you know, fat absorption, you're essentially preventing fat accumulation. The side effects of orlistat include gastrointestinal upset as well as diarrhea, a fatty stool.
Sympathomimetics can also be used for the treatment of obesity, and these include phentermine. Sympathomimetics really, they increase the sympathetic activity in your body, and so your fight or flight response, and so you increase energy expenditure.
Another very, very important treatment for obesity is bariatric surgery, and there are many types. There's the adjustable gastric band, so it really suppresses appetite by really, you know, reducing the amount of food that you can actually take in to your stomach. There's a sleeve gastrectomy, you're shaving off part of the stomach, and so you have less space for food. There's a Roux-en-Y gastric bypass. Which looks complicated, but really, the take-home message for bariatric surgery is that bariatric surgery is associated with a reduced all-cause mortality to non-surgical management for obesity. And what all-cause mortality means is that any death that occurs in patients who have obesity, regardless of the cause of the death.
So, I hope you enjoyed this video. We talked about obesity, how to measure weight using BMI or waist circumference, the different causes and risk factors for obesity, as well as the complications and treatment. Thank you for watching. I hope you enjoyed this video.
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