Obesity is defined as having an excessive amount of body fat caused by an imbalance between energy intake and expenditure..
The current standard measurement for obesity is the body mass index (BMI). In general, a BMI of 25 – 29.9 means you are overweight. Obesity is a BMI of 30 and above. Obesity is then classified into three categories:
Class 1: BMI of 30 – 34.9
Class II: BMI 35 – 39.9
Class III: BMI of 40 and greater
Obesity is common, serious and costly
Obesity is continue to be one of the world’s most costly and underserved growing medical conditions with significant unmet medical needs.
Worldwide, 2.8 million people die each year as a result of being overweight (including obesity and an estimated 35.8 million (2.3%) of global DALYs(Disability-adjusted life year) are caused by overweight or obesity.
Raised BMI also increases the risk of cancer of the breast, colon/rectum, endometrium, kidney,oesophagus (adenocarcinoma) and pancreas. Mortality rates increase with increasing degrees of overweight, as measured by BMI.
The worldwide prevalence of obesity has nearly doubled between 1980 and 2008. In 2008, 10% of men and 14% of women in the world were obese (BMI ≥30 kg/m2), compared with 5% for men and 8% for women in 1980. An estimated 205 million men and 297 million women over the age of 20 were obese in 2008 – a total of more than half a billion adults worldwide
Almost 36 percent of U.S. adults are obese, a condition that can lead to heart disease, Type 2 diabetes and stroke, according to the Centers for Disease Control and Prevention. The annual cost of managing obesity in the United States alone amounts to approximately $190.2 billion per year, or 20.6% of national health expenditures.
Obesity and Arthritis
Obesity rates are 54% higher among adults with arthritis compared to those without the condition. Obesity is common among people with arthritis and is a modifiable risk factor associated with arthritis-related disease progression, activity limitation, disability, reduced quality-of-life, total joint replacement, and poor clinical outcomes after joint replacement.
Obese persons with arthritis may have a difficult time losing weight because pain may limit their mobility and physical activity, which is a key part of weight loss. However, low impact physical activity and dietary changes can lead to successful weight loss for persons with arthritis. In fact, losing as little as 10-12 pounds can make a difference in pain and function.
Limitation of current treatment
Although prevention is the long-term goals, treatment is required for those who are already obese. Surprisingly, however, treatment options remain quite limited.
Current anti-obesity drugs aim to reduce food intake by either curbing appetite or suppressing the craving for food. However, many of these agents have been associated with severe psychiatric and/or cardiovascular side effects, highlighting the need for alternative therapeutic strategies.
Currently available weight loss treatments function by blocking fat absorption or signaling feelings of fullness or diminished appetite in the brain. These drugs are modestly effective that fails to provide sustainable weight loss in many patients, and, in some subjects, they are associated with unacceptable and life-threatening adverse effects.
Bariatric surgery for severe obesity is effective but costly and risky
Bariatric surgical procedures are generally used for patients with morbid obesity (BMI of 40 or more, or have a BMI of 35 to 39.9 along with serious obesity-related health problems).
Bariatric surgery is much more effective in terms of weight loss, comorbidity reduction. However, owing to concerns about perioperative mortality, surgical complications, the frequent need for reoperation, and high costs, these procedures tend to be reserved for the severe obesity.
There are high unmet medical needs for the development of safe and efficacious drug treatments for severe obesity.
There is a growing need for pharmaceutical companies to find effective, safe, and well-tolerated antiobesity drugs.
An alternative strategy to surgery is to develop therapeutic agents that can reduce fat mass directly by increasing oxidation of fatty acids, increasing energy expenditure, and /or decreasing the consumption of foods.
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R. John Rodgers et al, Anti-obesity drugs: past, present and future, Dis Model Mech. 2012 September; 5(5): 621–626.
Barber TM et al, The incretin pathway as a new therapeutic target for obesity, Maturitas. 2010 N ov;67(3):197-202
Global status report on noncommunicable diseases 2010. WHO
Center for Disease Control and Prevention