The number of people worldwide who suffer overweight (body mass index [BMI], calculated as a person’s weight in kilograms divided by the square of their height in meters, ≥ 25) and obesity (BMI ≥ 30) is staggering at 1.7 billion people. The United States has the highest percentage of overweight adults affecting over two thirds of the population with over half that population being obese. A closer look at the most rapidly growing BMI segments are 35 and 40, 23 million and 8 million people respectively. With the rise in obesity there is also a concomitant rise in comorbidities including type two diabetes (T2D), hypertension, hyperlipidemia, heart disease, stroke and others conditions that then account for more than 2.5 million world-wide deaths. In fact, when compared to a normal weight person a 25-year-old male that is morbidly obese can expect to lose 12 years off their life, or a 22% reduction in expected lifespan.
In a systematic review and meta-analysis of bariatric surgery completed in 2004 it was concluded (134 primary studies that included 179 treatment groups and n = 22,094 patients) that “a substantial majority of patients with diabetes, hyperlipidemia, hypertension and obstructive sleep apnea experienced complete resolution or improvement.” In the studies selected for this analysis 41.8% were based in North America, 43.3% in Europe and 14.9% in other nations (Australia, New Zealand, South America, Japan, Israel, Saudi Arabia and Taiwan). The population analyzed experienced amelioration of their diabetes with 48% of patients that underwent laparoscopic adjustable gastric banding, 84% who underwent gastric bypass and 98% who underwent biliopancreatic diversion/duodenal switch. Several years later Buchwald et. al. completed another meta-analysis and systemic review that specifically looked at weight and T2D post bariatric surgery.
In a 2009 meta-analysis and systemic review of weight and T2D post bariatric surgery, 621 studies that included 888 treatment arms and over 135,000 patients concluded that, “the clinical and laboratory manifestation of type 2 diabetes are resolved or improved in the greater majority of patients after bariatric surgery.” Of the entire analyzed cohort:
- 78.1% experienced complete diabetes resolution
- 86.6% experienced improvements in their diabetes
- Biliopancreatic diversion/duodenal switch had the greatest amelioration
- Gastric Bypass had the second greatest amelioration
- Banding procedures had the least ameliorative effects
- Improvements last at least 2 years post-surgery
When looking at the overarching impact of bariatric surgery on diabetes it’s clear that bariatric surgery is not only an effective solution, but also one that seems to have long-term and lasting effects for the patient. While data should be continuously monitored for updates to these meta-analyses, it would be prudent to collect 5, 10 and 15+ year and more follow-up data to continually monitor this lasting effect. It’s promising, though, that in comparison to traditional methods of managing diabetes bariatric surgery seems to be the single most efficacious solution to a world-wide health pandemic that does not seem to be slowing down.
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