THIRUVANANTHAPURAM : Obesity has become a significant global health challenge with an increasing prevalence in both developed and developing countries. The worldwide occurrence of obesity has nearly tripled in the last 40 years, and 31.3 per cent of India’s population was diagnosed positive in the year 2015.
Obesity is associated with a plethora of metabolic diseases including cardiovascular anomalies, hypertension, diabetes mellitus, dyslipidemia, and sleep apnea. The primary cause of obesity may be genetic—including monogenic disorders and conditions like Prader—Willi. Secondary causes may be neurological illnesses like brain injury, tumours, hypothalamic obesity), endocrine imbalances like hypothyroidism or depression or drug-induced problems like the effects of antidepressants and beta-blockers.
Obesity causes decreased cardiac output, increased left ventricular wall thickness and accelerates atherosclerosis. It also results in diabetes by altering levels of adipocytokines, increasing circulation of free fatty acids and altering body fat distribution, causing insulin resistance and increased blood glucose levels. Weight loss can bring in significant differences in this condition. A loss of 5-10 per cent has been shown to improve hypertension, insulin resistance, and glycemic control. In the diabetes prevention program, a cut-back of approximately 7 per cent achieved through lifestyle changes was associated with a 58 per cent reduction in the risk of developing type 2 DM in obese, prediabetic individuals. A weight loss of 10 kg increased life expectancy by 35%.
While many methods for weight loss are available these days, lifestyle interventions and maintaining a healthy diet are most preferred. All scientific guidelines mandate at least 150 minutes of moderate aerobic exercise per week, along with 3 weekly sessions of resistance training. Mediterranean diet which is rich in vegetables, fruits, lean meat and fish cooked in olive oil is shown to aid in weight loss.
Drug therapy is indicated when lifestyle interventions fail in long-term weight management of patients who are obese—with body mass index >30 kg/m2 or those who have BMI between 27-29.9 with obesity-related morbidity (eg diabetes, hypertension, etc). Doctors were facing a holy grail when it came to safe and effective anti-obesity molecules for non-diabetic obese patients until we found the answer in lorcaserin.
This drug is promising as it acts on the 5HTc receptor selectively and stimulates them in the appetite center of the brain. This further reduces food intake and increases a feeling of fullness, thus aiding weight loss. Compared to other similar molecules it has fewer cardiovascular side effects like valvular heart disease.
It helps in effective weight loss when taken on a long term basis accompanied by exercise and diet control. This, in turn, will reverse many of the obesity-related complications mentioned earlier too. However, It cannot be used in those with major depressive disorders. Surgery is yet another way to beat extreme cases of obesity. Bariatric surgery is a good option for those with a BMI above 40, but all surgeries have their own set of complications. An appropriate weight-loss strategy must be chosen only after taking aspects like cardiovascular safety, and maintenance of kidney health into account.
Dr Joseph K Joseph
The author is a consultant in internal medicine and diabetes at VPS Lakeshore hospital. Views expressed are his own.