March 2, 2024

Obesity, defined by the World Health Organization, as “excess or abnormal fat accumulation that presents a risk to health” is a chronic disease that continues to increase in prevalence among children, adolescents, and adults worldwide.
Overweight is defined based on body mass index or BMI of 25 to 29.9 kg/m2 and obesity as BMI of 30 kg/m2 or higher. Class 3 or extreme or severe obesity is having BMI greater than 40 kg/m2.
Just as high death rate or risk of hospitalization is associated with BMI less than 20 kg/m2, excess body weight contributed to about four million deaths globally in 2015 and more than 320,000 deaths in the United States in 2014.
Aside from cardiovascular diseases, other medical conditions closely associated with obesity include cancer, gout, osteoarthritis, gallstone formation, nonalcoholic fatty liver disease, infertility, endometriosis, kidney disease, kidney stones, urinary incontinence, depression, asthma, infection, influenza to name a few.
Treatment of obesity starts with counseling and evaluation of a person’s medical status. The physician has to look for underlying illnesses like diabetes mellitus, abnormal cholesterol levels, elevated blood pressure, heart disease, sleep apnea, and symptomatic osteoarthritis.
The goals of treatment need to be defined and these are to help the patient lose weight and to help improve his overall health and quality of life. The first and basic treatment is lifestyle modification in the form of diet or healthy eating, exercise, and behavioral modification. The patient has to believe that his/her weight can be controlled and participate or cooperatein planning the weight control treatment.
If a person does not lose at least five percent of total body weight at three to six months with lifestyle modifications alone, drug therapy is considered for persons with BMI of 30 kg/m2 and above or BMI of 27 to 29.9 kg/m2 with weight-related conditions mentioned earlier. Treatment is individualized and the benefits, cost, and side effects are all considered, including the person’s choice.
Drugs used in the treatment of obesity include the following: GLP-1 or glucagon-like peptide receptor agonists liraglutide by daily injection and semaglutide by weekly injection; Phentermine-Topiramate combination; Orlistat; Bupropion-Naltrexone combination; Phentermine; Benzphetamine; Phendimetrazine; and Diethypropion.
These medications are prescription drugs to be used under a doctor’s supervision and not through self-medication. There are guidelines on how their safety and efficacy is assessed, the blood tests to be taken while monitoring a patient’s response, and adverse effects to be observed. The doses also need to be adjusted based on guidelines.
Recommended first line drugs in weight management are the GLP-1 receptor agonists because of their added cardiovascular and renal benefits on top of weight control. These drugs stimulate glucose-dependent insulin secretion by the pancreas, inhibit the release of the hormone glucagon, and delay emptying of the stomach (this leads to a sensation of being full and hence reduced food intake). Semaglutide and Liraglutide both have demonstrated efficacy in weight management in patients with and without type 2 diabetes mellitus.
They have been shown to decrease cardiovascular complications in adults with type 2 diabetes with established heart disease or chronic kidney disease.
The adverse events that may occur during use of these drugs include nausea and vomiting, diarrhea, and hypoglycemia. Rare cases of pancreatitis (inflammation of the pancreas) have been reported. The doses of GLP-1 receptor agonists are adjusted based on a patient’s response, presence of adverse reactions, and the goals of therapy that are attained- the weight loss and the general health well-being of the patient.
Regaining weight may occur when a drug is stopped.
Studies have shown that lifestyle modifications plus drug therapy can lead to five to 22.5 percent weight loss. Bariatric surgery is an option when lifestyle modifications and drugs don’t work.