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The following section covers the various means of treating obesity, including dietary changes, medications, and/or surgical options. Diet plays a critical role in all of these options.
4.1 Assess the Patient’s Readiness and Willingness to Lose Weight
The previous sections provide the rationale for assessment of the health risks associated with obesity, the potential health benefits accruing from weight loss, and the importance of then maintaining a healthy body weight. Weight control requires behavioral change, which cannot happen without patient buy-in to the process. Therefore, the health risks of overweight and obesity need to be communicated, and patient readiness to change needs to be established. Table 7 outlines the various stages of behavior change as conceptualized by Kushner based on Prochaska’s model of behavior change, often referred to as the Transtheoretical Model of Behavior Change (6). It is important to note many patients will not progress through the outlined stages linearly, but rather will go back and forth repeatedly among stages. Therefore, timing is important and the clinician must watch for an appropriate time to bring up or follow through on the issue.
Table 7Transtheoretical Model of Behavior Change (5)
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|Stage||Characteristics||Patient Verbal Cues|
|Pre-contemplation||Unaware of problem, no interest in change||“I’m not really interested in weight loss. It’s not a problem.”|
|Contemplation||Aware of the problem, beginning to think of changing||“I need to lose weight but with all that’s going on in my life right now, I’m not sure if I can.”|
|Preparation||Realizes benefits of making changes and thinking about how to make change||“I have to lose weight, and I’m planning to do that.”|
|Action||Actively taking steps toward achieving the behavioral goal, but only for a brief period (less than 6 months)||“I’m doing my best. This is harder than I thought.”|
|Maintenance||Initial treatment and behavioral goals reached and sustained for a longer period of time (e.g., more than 6 months)||“I’ve learned a lot through this process.”|
Often, those who are at highest health risk due to obesity are unaware of how serious their weight-related problems are, or are in deep denial about them. The consequences of excess weight, including long-term implications, must therefore be raised and carefully explained. Helping patients to draw connections between the short-and long-term health consequences of their current weight, and the implications this will have on things they care about, such as their family or the ability to participate in activities they enjoy, may aid in empowering patients to progress through the various stages of behavior change.
Once patient readiness and willingness to lose weight has been established, a plan of attack needs to be jointly devised with the patient. Some patients are ready to start a treatment program immediately, and the patient and counselor are able to begin setting goals together right away. Other patients have reservations or other issues keeping them from reaching the action stage needed to embark upon their weight loss goals, making it important for the counselor to address these road-blocks before moving on. For patients who are not ready to act, the issue should be deferred and brought up again at the next visit, rather than dropping the subject entirely. Some groups of patients are unable or unwilling to embark on a weight reduction program at all. Even patients who are unwilling to embark on a reducing diets may be willing to take steps to avoid further weight gain, or may be willing to work on other risk factors such as smoking cessation or increasing physical activity. These activities should be encouraged. For those who are ready and raring to go, a referral to a registered dietitian should be provided where the subject can be addressed in-depth.
4.2 Decide if Dietary Treatment is the Appropriate Option
Weight reduction with dietary treatment is in order for virtually all patients with a BMI over 30, as well as those with a BMI of 25-29.9 with comorbidities. A dietary approach to weight loss should be executed in the context of comprehensive lifestyle intervention whenever possible. This type of intervention involves frequent, in-person encounters with a trained interventionist in an individual or group setting, and incorporates a moderately reduced calorie diet, increases in physical activity, and the use of behavioral techniques to facilitate adherence to recommendations. The gold standard is a comprehensive, high-intensity, on-site program with greater than 14 sessions in 6 months, provided either in a group or individually, by a trained interventionist, and lasting for at least 1 year. When a comprehensive lifestyle intervention is not feasible, other dietary-based approaches, such as electronically based programs and commercial programs, which will be discussed in further detail later, can be appropriate alternatives (23).
For some patients, however, a low calorie (hypocaloric) diet alone may not be enough to prompt significant and lasting weight loss (34).For patients who have failed to lose on a comprehensive lifestyle program, for those with a BMI greater than 30, or greater than 27 if one or more comorbidities are present, and who are likely to have little success with a purely dietary approach on the basis of a history of many failures, other steps may be in order. This is especially important for those with class 2 (BMI>35) and 3 (BMI > 40) obesity, referral to a multidisciplinary obesity treatment team for adjunctive therapies (i.e., very low calorie diets, pharmacological treatment, and/or gastric bypass surgery) is warranted (23).
4.3 Decide if Drugs will be Useful Adjunctive Therapy to the Reducing Diet
Prescription drugs are one form of adjunctive therapy that may be considered for those with a BMI greater than 30, or a BMI of 27 and above if one or more comorbidities are present, who are unable to lose weight with dietary measures alone. Weight loss drugs are only adjuncts to, rather than substitutes for, reducing diets, however, and a reducing diet will still be necessary. Without a hypocaloric diet, drugs are unlikely to be effective. The addition of weight loss medication to a dietary-based weight loss regimen can help patients lose up to 10% of their initial body weight, with most weight loss occurring in the first six months (35). Table 8 provides an overview of prescription medications that are available. Note that none are totally free of side effects.
Table 8Prescription Medications Available in the United States for Weight Loss (26)
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|Generic Name+ (Trade Name)||Food and Drug Administration Approval for Weight Loss||Drug Type||Common Side Effects|
*OTC Brand: AlliTM
|Yes; long term for adults and children age 12 and older|
*AlliTM for adults only
|Lipase Inhibitor||Gastrointestinal issues (cramping, diarrhea, oily spotting)|
Do not take with cyclosporine
|Yes; long term for adults||Serotonin Receptor Antagonist||Headache, dizziness, nausea, fatigue, dry mouth|
Do not take with Selective Serotonin Reuptake Inhibitors (SSRIs) or Monoamine Oxidase Inhibitors (MAOIs)
|Phentermine-Topiramate (QsymiaTM)||Yes; long term for adults|
Contrindicated in women who are pregnant or may become pregnant
|Appetite Suppressant/Seizure Treatment||Tingling of hands and feet, trouble sleeping, taste alterations, dry mouth constipation, dizziness, birth defects|
|Bupropion – Naltrexone|
|Yes; long term for adults||Depression Treatment/Alcohol and Opioid Abuse Treatment||Nausea, constipation, headache, vomiting, dizziness, insomnia, dry mouth, diarrhea, increased blood pressure and heart rate, seizures, suicidal thoughts and behaviors|
(Adipex-PTM, SuprenzaTM, ZantrylTM)
|Yes; short term (up to 12 weeks) for adults||Appetite Suppressant||Increased blood pressure and heart rate, sleeplessness, nervousness|
|Yes; short term (up to 12 weeks) for adults||Appetite Suppressant||Dizziness, headache, sleeplessness, nervousness|
(Bontril PDMTM, AdipostTM, MelfiatTM)
|Yes; short term (up to 12 weeks) for adults||Appetite Suppressant||Sleeplessness, nervousness|
|Yes; short term (up to 12 weeks) for adults||Appetite Suppressant||Restlessness, anxiety, sleeplessness, headache|
|No||Depression Treatment||Dry mouth, insomnia|
|No||Seizure Treatment||Numbness of skin, change in taste|
|No||Seizure Treatment||Drowsiness, dry mouth, dizziness, headache, nausea|
|No||Diabetes Treatment||Weakness, dizziness, metallic taste, nausea|
Many of the Food and Drug Administration (FDA)-approved weight-loss medications are approved only for short-term use (short term is usually interpreted to mean use up to 12 weeks), although some physicians still prescribe them for longer periods of time (35). Only four prescription drugs are currently approved for long-term use in weight reduction: Orlistat (XenicalTM), Lorcaserin (BelviqTM), Phentermine-Topiramate (QsymiaTM), and Bupropion–Naltrexone (ContraveTM).
Orlistat is available for both prescription (XenicalTM) and over-the-counter at a lower dose as AlliTM. Over-the-counter AlliTM is available only to adults aged 18 and older, and is a half-dose version of prescription Orlistat (http://www.myalli.com) (35). Orlistat operates at the level of the gut to inhibit pancreatic lipase, blocking the absorption of about one third of fat consumed. Use over one to two years can lead to a weight loss of five to seven pounds (35). Adherence to a reduced calorie diet with less than 30% calories from fat is necessary while on either Orlistat or Ali. Both Orlistat and Ali’s disadvantages include fat malabsorption, sometimes accompanied by anal leakage, and decreased absorption of fat-soluble vitamins. Because of this decrease in fat-soluble vitamin absorption, patients taking either version of the drug should be advised to take a multivitamin supplement containing fat-soluble vitamins to ensure adequate nutritional status (35). Dietetic counseling is helpful in managing weight loss.
Lorcaserin (BelviqueTM) is another weight loss drug approved for long term use and is available by prescription only. Studies evaluating its effectiveness found that 47% of those who used the drug lost at least 5% of their initial body weight (35). QsymiaTM is another long-term weight loss drug that was approved by the FDA in 2012. QsymiaTM is a combination of an appetite suppressant, phentermine, and a seizure medication, topiramate. Studies found that after 1 year using the recommended dose of the drug, 62% of patients lost greater than 5% of their initial body weight (35). ContraveTM is the newest long-term drug to treat obesity, and was approved in September 2014. ContraveTM is a combination of bupropion, an antidepressant, and naltrexone, a medication used to treat alcohol and opioid dependence. Studies showed that after 1 year, 42% of the non-diabetic patients tested lost at least 5% of their initial body weight. (36). With all long-term weight loss drugs, if at least 5% of initial body weight is not lost by 12 weeks, use of the drug should be discontinued as it is unlikely to be effective later, and therefore the risks outweigh the putative benefits (35).
Phentermine (SuprenzaTM), phendimetrazine (AdipostTM), diethylpropion (TenuateTM), and benzphetamine (DidrexTM) are modestly effective prescribed anorectic agents approved for short-term use (12 weeks in a 12 month period) by the Food and Drug Administration (FDA) (35). Phentermine and diethylpropion are widely prescribed, as they are relatively inexpensive (approximately $30 for a one-month supply), and provide slight stimulatory effects. However, little research has been done on their long-term side-effects (39).
The off-label use of bupropion (WellbutrinTM), a drug originally approved by the FDA for aiding in smoking cessation, has become popular in the past few years for weight control. Bupropion enhances norepinephrine and weakly blocks dopamine reuptake and is being studied for the treatment of obesity. Bupropion could be considered if a patient presenting with obesity wanted to quit smoking as well and lose weight (38). Short term side effects most often reported are agitation, dry mouth, insomnia, headache, nausea, constipation, and tremor. However, its long-term effects on weight loss are not clear, and its use must be accompanied by a low-calorie diet if it is to help in weight loss.
Topiramate (TopamaxTM) and zonisamide (ZonegranTM) are anticonvulsants that were originally approved to treat epilepsy. They are also sometimes used off-label for their weight-loss effects. However, adverse effects have also been reported, most commonly difficulty with memory, parathesia, difficulty concentrating, and mood problems. These drugs are approved by the FDA for epilepsy only, and not for weight loss (38).
Metformin (GlucophageTM) is a diabetes medication that may promote small amounts of weight loss in people with obesity and type 2 diabetes. One study found that patients treated with metformin for diabetes lost 2kg more at 6 months compared to placebo, and maintained at 1 kg at 4 years follow-up. It is unclear, however, if weight loss on metformin is related to improved glucose tolerance or the drug itself (40).
ByettaTM (exenatide) and pramlintide are sometimes used in treating the comorbidities of obesity. Both compounds affect the gastrointestinal hormones that regulate glucose homeostasis, gastric emptying, and satiety. Exenatide (ByettaTM) is used as an adjunctive therapy for improving glycemic control in patients with type 2 diabetes who also take metformin or sulfonylurea. Pramlintide is an adjunctive therapy for patients with type 1 or type 2 diabetes who use insulin at mealtimes. Usually patients with diabetes gain weight with better glucose control, however, with these drugs, better blood glucose control is often associated with weight loss, at least in preliminary studies. The most common side effect of these medications is nausea (38).
Major disappointments have resulted as research on the once promising class of drugs known as cannabinoid (CB1) receptor antagonists has continued. Rimonabant (AcompliaTM) was the first CB1 receptor blocker approved for use in the world. Its suggested use was for patients with a BMI of 30 or more, in conjunction with exercise and diet, to aid in weight loss. CB1 receptors are located in the brain, gastrointestinal tract, adipose tissue, heart, pituitary, and adrenal glands, and if they are stimulated, these receptors increase appetite. Blockage of these receptors is thought to decrease appetite. However, the FDA ruled that Rimonabant carried too much risk to be approved for use in the United States, with side effects including nausea, anxiety, diarrhea, and depressed mood that, in severe cases, led to suicide (38). In 2009, the European Medicines Agency (EMEA) also concluded that the benefits of Rimonabant no longer outweighed the risks, and marketing authorization for the drug in the European Union was officially revoked (43). Investigation into the cannabinoid (CB1) receptor antagonist class of drugs has since ceased (39).
Other areas of research for future weight loss drugs include drugs combining appetite suppressants and those that affect addiction, drugs affecting gut hormones that influence appetite, drugs that work to shrink the blood vessels supplying fat cells, drugs targeting genes associated with obesity, and manipulation of gut bacteria (35).
Sibutramine (MeridiaTM) was a commonly used obesity drug first introduced in 1997. However, it was voluntarily withdrewn from US markets by its manufacturer in 2010 after clinical trial data indicated that the drug increased the risk for heart attack and stroke. It should not be prescribed or used for the treatment of obesity (44).
Some of the surprisingly positive effects with weight loss drugs are due the fact that the medications are not what they seem to be but rather adulterated and contain undeclared drugs. The FDA releases an extensive list of tainted weight loss products, many of which contain undeclared drugs (Table 9) (44). If patients are taking any of these contaminated products, they should be advised to stop immediately. Table 9 provides a comprehensive list of these tainted products on the market from 2011 onwards, along with the undeclared pharmaceutical/chemical included in the product. There are also other drugs that may be added although they are no longer available for distribution through legitimate sources because of adverse and sometimes fatal side effects including Fen-PhenTM, ReduxTM, PondimenTM, fenfluramine, MeridiaTM, and dexfenfluramine.
Table 9FDA’s List of Tainted Weight Loss Products (33)
The Undeclared Drug/Chemical Ingredient is Listed After Each Product in Parentheses
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|1 Day Diet (Sibutramine)||7 Days Herbal Slim (Sibutramine)||24 Ince (Sibutramine)|
|A-Slim 100% Natural Slimming Capsule (Sibutramine)||Acai Berry Soft Gel ABC (Sibutramine)||Advanced (Sibutramine)|
|Advanced Blue (Sibutramine)||Advanced Slim 5 (SIbutramine)||Asset Bee Pollen (Sibutramine)|
|Asset Bold (Sibutramine)||Asset Extreme (Sibutramine)||Asset Extreme Plus (SIbutramine)|
|B-Perfect (Sibutramine)||Be Inspired (Sibutramine)||Beautiful Slim Body (Sibutramine)|
|Bella Vi Insane Amp’d/Bella Vi Amp’d Up (Sibutramine)||Best Line Suplemento Alimenticio (Sibutramine)||Best Share Green Coffee: Brazilian Slimming Coffee (Sibutramine)|
|Bethel 30 (Sibutramine)||Body Beauty 5 Days Slimming Coffee (Sibutramine)||Botanical Slimming Soft Gel (Sibutramine)|
|Burn 7 (Sibutramine)||Celerite Slimming Capsules (Sibutramine)||Citrus Fit Gold (SIbutramine)|
|DaiDaiHuaJiaoNang (Sibutramine and Phenolphthalein)||Diet Master (Sibutramine)||Dr. Mao Slimming Capsules (Sibutramine)|
|Dr. Ming’s Chinese Capsule (Sibutramine)||Dream Body Slimming Capsule (Sibutramine)||Extreme Body Slim (Sibutramine)|
|Fat Zero (Sibutramine and Phenolphthalein)||Fruit & Plant Slimming (Sibutramine)||Fruit Plant Lossing Fat Capsule (Sibutramine)|
|Goodliness Fat-Reducing Capsules (Sibutramine)||Hot Detox (Sibutramine)||Infinity (Sibutramine)|
|Instant Slim/ Shou Fu Ti Tun Guo Xiang Xing Jian Fei Jiao Nang (Sibutramine)||Ja Dera 100% Natural Weight Loss Supplement (Sibutramine)||Japan Hokkaido Slimming Weight Loss Pills (Sibutramine, Benzocaine, Phenolphthalein and Diclofenac)|
|Japan Rapid Weight Loss Diet Pills Green (Phenolphthalein)||Japan Rapid Weight Loss Diet Pills Yellow (Sibutramine and Phenolphthalein)||Japan Weight Loss Blue (Sibutramine, Analogs of Sibutramine, and Ephedrine Alkaloids)|
|Jimpness Beauty Fat Loss Capsules (Sibutramine)||La Jiao Shou Shen (Sibutramine)||Leisure 18 Slimming Coffee (Sibutramine)|
|Lingzhi Cleansed Slim Tea (Sibutramine)||Lipo 8 Burn Slim (Sibutramine)||Lishou (Sibutramine)|
|Lite Fit USA (SIbutramine)||Lose Weight Coffee (Sibutramine)||LX1 (DMAA)|
|Magic Slim (Sibutramine)||Magic Slim Tea (Sibutramine)||Magic Slim Weight Reduction Capsule (Sibutramine)|
|MAXILOSS Weight Advanced (Sibutramine)||MAXILOSS Weight Advanced Blue (Sibutramine)||Meizi Evolution (Sibutramine)|
|Meizitang Citrus (Sibutramine)||Mix Fruit Slimming (Sibutramine)||Natural Body Solution (Sibutramine)|
|New You (Phenolphthalein)||P57 Hoodia (Sibutramine)||Pai You Guo Slim Tea (Sibutramine and Phenolphthalein)|
|Paiyouji Plus (Sibutramine)|