Treatment Guidelines
The goal of weight loss therapy for patients with cardiovascular disease (CVD) is to reduce or eliminate coronary heart disease (CHD) risk factors and improve cardiac function. Aggressive weight loss therapy could be harmful in selected patients, such as those who have had a recent myocardial infarction or stroke or who have unstable angina, and attempts at weight loss should be delayed until these patients are medically stable.
Clinical Evaluation
The physician's office should be an environment that is sensitive to the needs of obese patients. The waiting room should contain chairs without arms, large gowns and large blood pressure cuffs should be available, and a scale that can weigh patients who weigh >300 lb should be available and located in a private area. The initial assessment should include an appropriate history, physical examination, and laboratory tests.
History
In addition to a standard medical interview, a patient's history should include an assessment of (1) weight history (highest and lowest adult body weight, previous weight loss attempts, weight pattern, and potential triggers and social and environmental factors that contributed to weight gain), (2) dietary history, including an assessment of types and timing of meals and snacks and an attempt to identify possible triggers that result in excessive energy intake, (3) physical activity and function (daily and exercise activities, physical limitations, effect of obesity on physical lifestyle), (4) obesity-related health risk (age of onset and duration of obesity, family history of obesity and obesity-related medical complications, current obesity-related disease), (5) possible psychiatric illnesses, such as binge eating disorder and depression, that may require therapy before a weight loss program is initiated, and (6) ability to lose weight (desire to lose weight, weight loss goals and expectations, limitations for achieving weight loss, including medications and illnesses, lifestyle and work patterns, financial resources, and special needs).
Physical Examination
The patient's body-mass index (BMI) and waist circumference should be determined. BMI is generally correlated with percentage of body fat in a curvilinear fashion. Some people with an "obese" BMI, who have a normal amount of body fat and a large muscle mass, are not at increased risk for CHD, whereas people with a "normal" BMI, who have excessive body fat and small muscle mass, are at increased risk. Waist circumference, measured halfway between the last rib and the iliac crest, correlates with abdominal fat mass. The table below titled "Weight Classification by BMI" provides a classification of risk based on BMI. A waist circumference of >88 cm (35 in) for women and >102 cm (40 in) for men is associated with an increased risk of metabolic diseases and CHD. Additional assessments should include measuring blood pressure with a large cuff and searching for physical signs of right or left ventricular dysfunction, congestive heart failure, and pulmonary disease. An electronic stethoscope can increase a physician's ability to detect cardiac abnormalities in patients who are extremely obese.
Table: Weight Classification by BMI*
|
Obesity Class |
BMI kg/m2 |
Disease Risk |
Underweight |
|
<18.5 |
Increased |
Normal |
|
18.5-24.9 |
Normal |
Overweight |
|
25.0-29.9
| Increased
|
Obesity |
I |
30.0-34.9 |
High |
| II |
35.0-39.9 |
Very high |
Extreme Obesity |
III |
>40.0 |
Extremely high |
* Data from Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults -- The Evidence Report. National Institutes of Health. Obes Res. 1998;6:51S-209S.
Additional adiposity-related risk factors: waist circumference >40 (in men) and >35 (in women); weight gain of >5 kg since age 18-20 years.
Laboratory Tests
An electrocardiogram (ECG) is needed to check for evidence of CHD and to obtain a baseline tracing for future comparisons. Standard blood tests should be performed to search for CHD risk factors, including prediabetes (impaired fasting blood glucose or impaired glucose tolerance), dyslipidemia (increased triglycerides, low high density lipoprotein cholesterol [HDL-C], and increased low density lipoprotein cholesterol [LDL-C]), and the metabolic syndrome. Additional studies may be needed to further evaluate specific clinical suspicions based on the history and physical examination, such as sleep studies to diagnose obesity hypoventilation syndrome (OHS) or obstructive sleep apnea (OSA) and an exercise treadmill test or electron beam computerized tomography scanning or both to evaluate CHD risk. The comparative value of exercise tolerance testing and electron beam computerized tomography in obese subjects has not been determined. Exercise treadmill testing is not recommended for patients without cardiac symptoms, and neither exercise treadmill testing nor electron beam computerized tomography scanning should be performed in patients who are at low risk for CHD, based on clinical judgment or Framingham risk score.
Therapeutic Options
Appropriate management requires identifying patients who need treatment, developing a realistic treatment plan, and implementing a defined treatment strategy that can be modified as needed during long-term surveillance. The Practical Guide to the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults was developed by the North American Association for the Study of Obesity in conjunction with the National Heart, Lung, and Blood Institute. Suggested guidelines from the guide for selecting among different weight loss treatment options, based on disease risk, are shown in the table below titled "Weight Loss Treatment Guidelines." A typical clinical consultation involves a physician's giving advice without adequate consideration of the patient's priorities, motivation, or confidence in undertaking change. In contrast, obesity therapy should involve "patient-centered counseling," which encourages patients to set goals and express their own ideas for therapy, with input from the healthcare professional. The treatment plan also must take into account the patient's readiness for therapy and the patient's ability to comply with the proposed treatment plan. Realistic goals should be established and frequent follow-up visits should be scheduled to monitor progress, modify the treatment plan as needed, and provide encouragement. Effective therapy requires a long-term structured approach with continued support from the physician and other caregivers, particularly during periods of patient recidivism and weight regain.
Reducing energy intake is the cornerstone of weight management therapy. Providing appropriate nutrition counseling and the behavior modification therapy needed to implement dietary changes within the setting of a busy outpatient practice is difficult if not impossible for most physicians because they do not have the time or expertise to provide this kind of care. Therefore, referral to a reputable weight loss program or experienced dietitian should be considered, if these resources are available. Additional therapy with weight loss medications or bariatric surgery can be useful in properly selected patients.
Table: Weight Loss Treatment Guidelines*
BMI Category, kg/m2 |
Treatment |
25.0-26.9 |
27.0-29.9 |
30.0-34.9 |
35.0-39.9 |
>40.0 |
Diet, physical activity, behavior therapy, or all 3
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Pharmacotherapy**
|
|
With obesity-related disease
|
Yes
|
Yes
|
Yes
|
Surgery***
|
|
|
|
With obesity-related disease
|
Yes
|
* Data from Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults -- The Evidence Report. National Institutes of Health. Obes Res. 1998;6:51S-209S.
** Pharmacotherapy should be considered only in patients who are not able to achieve adequate weight loss by available conventional lifestyle modifications and who have no absolute contraindications for drug therapy.
*** Bariatric surgery should be considered only in patients who are unable to lose weight with available conventional therapy and who have no absolute contraindications for surgery.