What Is An Observational Study?A new study of weight loss surgery in England has found that use of of laparoscopic bariatric or other types of weight loss surgery has increased ten-fold in NHS hospitals since 2000. One possible reason behind the rise, say the researchers, is the greater demand from obese patients as they become more conscious of the surgery as a feasible treatment alternative. The observational population cohort study was carried out by a team of researchers based at Imperial College London. It was published 26 August 2010 in the British Medical Journal.
Bariatric surgery is an operation that is performed on people who are morbidly obese, in order to help them lose weight. This goal is typically achieved by reducing the size of the stomach with a surgical band, as in gastric banding, by re-routing the small intestines to a small stomach pouch, as in a gastric bypass, or by removing a portion of the stomach, as in sleeve gastrectomy.
Bariatric surgery, which has been shown to reduce hospital admission, risk of death, and long term cost to the health service, is usually recommended for people with a body mass index of at least 40 or of at least 35 if accompanied by coexisting disease that could be improved by weight loss, and for whom all non-surgical treatments for weight loss have failed. Up until recently, little has been known about the demographics of who is actually having bariatric surgery in England.
Elective Bariatric Procedures
Using the Hospital Episode Statistics database, the researchers involved in the study identified all adult patients who had a first elective bariatric procedure (gastric bypass, gastric banding or sleeve gastrectomy) between April 2000 and March 2008. Mortality rates 30 days and one year after surgery were recorded, as well as duration of hospital stay and unplanned readmission rates.
A total of 6,953 bariatric procedures were carried out during the study period, and the number of procedures rose more than ten-fold from 238 in 2000 to 2,543 in 2007. Patients selected for gastric banding had lower post-surgery mortality and readmission rates and a shorter length of stay than those selected for gastric bypass. Patients with comorbidities showed poorer post-surgery outcomes than did other patients.
The percentage of laparoscopic procedures also increased during this time, from 28% in 2000 to 75% in 2007. However, no significant increase in mortality or unplanned readmission was seen over the study period, suggesting that laparoscopy has been introduced in a safe manner into the NHS, say the authors. “In conjunction with the growing level of obesity,” they say, “as patients become more aware of surgery as a viable treatment option, demand for surgery among morbidly obese patients increases.”
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