Obesity and Overweight: How to Tell, What to Do

Determining that an individual is overweight or obese may involve a team of clinicians and a variety of assessments conducted in controlled environments, such as a medical office or hospital. There are several methods that can be used to determine if a patient is overweight or obese. For example, bio-electrical impedance analysis involves the measurement of body fat in relation to lean body mass. Hydrostatic underwater weighing is a technique of obtaining a weight while the patient is in the water. Dual energy x-ray absorptiometry involves the measurement of bone mineral density (BMD). Waist-to-hip measurements may also be included. This measurement is obtained by dividing the circumference of an individual’s waist by their hips.^1–2

Perhaps more commonly recognized, body mass index (BMI) is a screening tool used to identify individuals who may be at increased health risk due to being overweight or obese. BMI involves a numeric value calculated by dividing weight by height squared. Once obtained, the patient’s BMI results can be compared to the numeric system to assist in determining the patient’s weight status. Examples of BMI values can be found in Tables 1 and 2.^3–5

The BMI system includes subcategories depending on the value obtained. Clinically severe obesity is considered to be either a BMI of 40 or more, or a BMI of 35 or more plus a serious health problem linked to obesity. Examples of health problems linked to obesity include type 2 diabetes, heart disease, sleep apnea, lung disease and arthritis. An individual with a BMI above 40 is considered to be morbidly obese. These patients are likely to be recommended for surgical intervention and may have a higher weight-related mortality rate.^3–5

Weight-Loss Treatment Options

If a patient is overweight or obese and treatment is indicated, there are a variety of options. Treatment can range from education on healthy eating habits to implementing routine exercise to the prescription of medicines and, as a last resort, bariatric surgery. Treatment plans may implement several of these options simultaneously. No two situations are identical, and each requires a thorough review and evaluation regarding treatment options and outcome expectations.^6–8

Bariatric surgery may be an option for individuals who are unable to lose weight by other means or who suffer from serious health problems (e.g., congestive heart failure) related to obesity. In some cases it may also be considered for patients who are unable to achieve a 5% decrease in weight with diet and lifestyle modifications. Bariatric surgery is not a novel procedure. There were more than 100,000 procedures in 2003 and more than 150,000 in 2005.^6–9

The surgical approach to weight loss is accomplished by either restricting the size of the stomach or bypassing a section of the intestines. Reducing the size of the stomach restricts the amount of food a patient can consume during a single meal. Malabsorptive procedures, such as bypass, decrease the nutrients absorbed from a meal. Similar to other medical conditions, prior to determining specific treatment options, there are numerous factors the clinician and provider will need to consider.^6–10 For examples see Table 3.

Weight-loss surgery may be performed using an open technique or laparoscopic technique. In an open approach, the surgeon dissects the abdomen to perform the surgery. In laparoscopy, surgeons insert instruments through small incisions and guide a small camera that sends images to a monitor. Of the two options, laparoscopic tends to involve a smaller incision, creates less tissue damage, is associated with shorter hospital stays and may have fewer complications. Not all individuals are suitable for laparoscopy. Patients who are extremely obese, who have had previous stomach surgery or who have complex medical problems may require the open approach.^{6–9, 11}

There are several surgical options that can be used with weight-loss surgery. The following summarizes four common approaches used in the United States (see Figure 1): adjustable gastric band (AGB), Roux-en-Y gastric bypass (RYGB), biliopancreatic diversion with a duodenal switch (BPD-DS) and vertical sleeve gastrectomy (VSG). Weight loss following each procedure can vary. For example, the percentage of weight loss is about 48% after adjustable gastric banding and approximately 60% after sleeve gastrectomy and gastric bypass. Patients who have bypass surgery generally lose two thirds of their excess weight within two years.^{6–9, 11–12}

Adjustable gastric band—AGB primarily works through reducing food intake. This is accomplished by placing a small bracelet-like band around the top of the stomach to restrict the size of the opening from the throat to the stomach. The surgeon can control the size of the opening with a circular balloon inside the band. The balloon can be inflated or deflated with saline solution.^{6–9, 11–12}

Roux-en-Y gastric bypass—RYGB restricts food intake as well as food absorption. Food intake is limited by a small pouch that is similar in size to the pouch created with AGB. RYGB allows food to be sent directly from the pouch into the small intestine. Food is subsequently absorbed differently because the stomach, duodenum and upper intestine do not have contact with it.^{6–9, 11–12}

Vertical sleeve gastrectomy—VSG surgery restricts food intake and subsequently decreases the amount of food digested. In this procedure most of the stomach is removed. This may result in a decrease in ghrelin, a hormone that prompts appetite. Low amounts of ghrelin may reduce hunger more than restrictive surgeries such as AGB.^{6–9, 11–12}

In the past VSG had been performed as part of the first stage of other procedures in patients who were, due to body weight and/or medical issues, at high risk for problems from more extensive types of surgery. Contemporary theory is that VSG alone may be sufficient, thereby negating the need for a second or more complicated procedure.^{6–9, 11–12}

Biliopancreatic diversion with a duodenal switch—This surgery includes three parts. One is to remove a portion of the stomach; this makes the patient feel full sooner while eating. Another is rerouting food away from a majority of the small intestine. This limits what the body can absorb and/or how it digests food. The third changes how bile and other digestive juices affect the body’s ability to digest food and absorb calories, thereby influencing body weight.^{6–9, 11–12}

In this procedure the surgeon creates a tubular “gastric sleeve,” as in a vertical sleeve gastrectomy. The smaller stomach sleeve remains linked to a very short part of the duodenum, which is then linked directly to a lower part of the small intestine. This surgery leaves a small part of the duodenum available to absorb food, vitamins and minerals. As a result, food bypasses most of the duodenum. The distance from the stomach to the colon is also shortened. This limits how food is absorbed and tends to produce weight loss.^{2, 6–9, 11–12}

Of the procedures summarized above, gastric bypass is the most common. It tends to result in greater weight loss and less weight regain. It is also reported to be very effective in resolving obesity-related diseases, such as diabetes, high cholesterol and high blood pressure. In 2002 it was reported to account for more than 75% of all bariatric-related surgeries.^{2, 6–9, 11–12}

While this discussion has primarily addressed adult weight loss, there may be cases where weight loss surgery needs to be considered for children. Nearly 2,700 youth weight-loss surgeries were performed from 1996–2003. Evaluation of the child will require clinicians with expertise in child weight loss and the use of specific criteria. Depending on the reference consulted, it is suggested that prior to surgery being considered, the patient must have tried unsuccessfully to lose weight for a minimum of 6 months. The patient should also be evaluated for factors such as BMI of 40 or more, reaching adult height and experiencing serious health problems (e.g., sleep apnea) linked to their weight that might be improved with surgery.⁹

References

1. Doylestown Hospital. Bio-Electrical Impedance Analysis (BIA)—Body Mass Analysis, https://www.dh.org/Bio-ElectricalImpedanceAnalysisBIA-BodyMassAnalysis.

2. International Atomic Energy Agency. Dual Energy X ray Absorptiometry—Bone Mineral Densitometry, https://rpop.iaea.org/RPOP/RPoP/Content/InformationFor/HealthProfessionals/6_OtherClinicalSpecialities/DEXA/.

3. Sturm R. Increases in clinically severe obesity in the United States, 1986–2000. Arch Intern Med, 2003 Oct 13; 163(18): 2,146–8.

4. Roller Weight Loss & Advanced Surgery. Obesity, www.rollerweightloss.com/info/obesity.html.

5. National Heart, Lung and Blood Institute. Assessment of Weight and Body Fat, www.nhlbi.nih.gov/guidelines/obesity/e_txtbk/txgd/411.htm.

6. U.S. Food and Drug Administration. Obesity Treatment Devices, www.fda.gov/MedicalDevices/ProductsandMedicalProcedures/ObesityDevices/default.htm.

7. Weight-control Information Network. Bariatric Surgery for Severe Obesity, win.niddk.nih.gov/publications/PDFs/Bariatric_Surgery_508.pdf.

8. Agency for Healthcare Research and Quality. Pharmacological and Surgical Treatment of Obesity, https://archive.ahrq.gov/clinic/epcsums/obesphsum.pdf.

9. Weight-control Information Network. Bariatric Surgery for Severe Obesity, https://win.niddk.nih.gov/publications/gastric.htm.

10. Collopy KT, Kivlehan SM, Snyder SR. How Obesity Impacts Patient Health and EMS. EMS World, www.emsworld.com/article/10654895.

11. National Association for Weight Loss Surgery. Weight Loss Surgery Statistics and Definitions, www.nawls.com/public/102.cfm?sd=2.

12. American Society of Plastic Surgeons. Obesity Epidemic Means Bariatric Surgery Rates Continue to Rise: Plastic Surgeons Play Key Role in Body Contouring After Massive Weight Loss, www.plasticsurgery.org/news-and-resources/press-release-archives/2012-press-release-archives/obesity-epidemic-means-bariatric-surgery-rates-continue-to-rise.html.

Paul Murphy, MS, MA, EMT-P, has administrative and clinical experience in healthcare organizations.

Chris Colwell, MD, is director of emergency medicine at the Denver Health Medical Center and medical director of the Denver Paramedic Division and Denver Fire Department.

Gilbert Pineda, MD, FACEP, is medical director for the Aurora Fire Department and Rural/Metro Ambulance in Aurora, CO, as well as an attending physician in the emergency department at the Medical Center of Aurora.