Lifestyle Modification Plus Medication More Effective Than
Medication Alone for Weight Loss in Obese Adults
A new study shows that treatment with a lifestyle modification program of diet,
exercise and behavioral therapy when used in combination with the weight loss
medication sibutramine (Meridia®) resulted in significantly greater weight loss
among obese adults than treatment with the medication alone. The study, conducted
by researchers from the University of Pennsylvania, appears in the November 17,
2005 issue of The New England Journal of Medicine and was supported by the National
Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), one of the National
Institutes of Health (NIH).
“NIH is fighting the increasing problem of obesity in America by supporting
research that will result in better treatments and therapies for weight loss
and the prevention of obesity's associated diseases, such as type 2 diabetes,
heart disease, and some forms of cancer,” says NIH Director Elias A. Zerhouni,
M.D.
“Lifestyle modification should be the first line of treatment for obesity,” says
Susan Yanovski, M.D., director of the Obesity and Eating Disorders Program for
NIDDK, and author of an accompanying editorial in the journal. “But for obese
adults who can’t lose enough weight to improve their health, medication used
as an adjunct can help.”
“The take home message is that weight loss medications will be most effective
when they are combined with a reduced calorie diet and increased physical activity,” says
Thomas A. Wadden, Ph.D., Professor of Psychology in the Department of Psychiatry
at the University of Pennsylvania School of Medicine, and lead author of the
study. “Weight loss medication used alone can produce some weight loss, but lifestyle
modification treatment can help patients acquire skills to successfully make
changes in their diet and physical activity.”
A total of 224 obese adults aged 18 to 65 years participated in the one-year
study. Participants were randomly assigned to one of four groups: 1. weight loss
medication alone; 2. lifestyle modification alone; 3. weight loss medication
plus lifestyle modification; and 4. weight-loss medication plus brief physician-mediated
therapy. The researchers included the fourth treatment group to measure the effectiveness
of weight-loss medication combined with brief lifestyle modification counseling
delivered by primary care providers. The researchers looked at this type of therapy
as a possible model for delivering lifestyle modification therapy in the setting
of primary care practice.
Participants in the lifestyle modification therapy group attended a total of
30, 90-minute group meetings. During the meetings participants were instructed
to complete and share weekly assignments, which included keeping detailed daily
food and physical activity records. Participants in the brief lifestyle modification
counseling group met with primary care physicians eight times for 10 to 15 minute
visits, where they were given homework assignments, which also included keeping
daily food and activity records. Participants in the weight-loss medication therapy
alone group also met with primary care physicians eight times for 10 to 15 minute
visits, but were not instructed to keep food or activity records and were provided
only general information on diet and exercise. Those participants in the combined
therapy group received both the lifestyle modification therapy and the weight-loss
medication. All groups were prescribed a 1200 to 1500 calorie diet and the same
exercise plan.
After one year, patients in the weight-loss medication plus lifestyle group
lost an average of more than 26 pounds — more than double the weight loss seen
with medication alone (11 pounds). In addition, 73 percent of participants in
the combined therapy group lost 5 percent or more of their initial body weight,
compared to 56 percent of participants in the brief therapy plus weight-loss
medication group, 53 percent of participants in the lifestyle modification alone
group, and 42 percent of participants in the weight-loss medication alone therapy
group. More than half or 52 percent of people in the combined therapy group lost
10 percent or more of their initial body weight compared to 29 percent of participants
in the lifestyle modification alone group, 26 percent of participants in the
brief therapy plus weight-loss medication group, and 26 percent of participants
in the weight-loss medication alone group.
Interestingly, those participants in the combined therapy group who were most
successful were those who frequently recorded their food intake. Those participants
with high adherence to food intake record keeping lost more than twice as much
weight as those with low adherence (41.5 versus 17 pounds).
“Some people have questions about how they can do lifestyle modification,” says
Dr. Wadden. “I think that a first step is to complete daily food logs. Food records
help people become aware of their eating patterns and identifying areas for improvement.” Dr.
Wadden adds that the second step to weight loss is to increase physical activity
and one of the best ways to do that is to obtain a pedometer to count steps and
gradually increase daily walking.
One limitation of the study is that it only included obese patients who were
otherwise healthy and excluded obese patients with health problems possibly related
to their obesity, such as hypertension, cardiovascular disease, cerebrovascular
disease, kidney disease, liver disease, and diabetes. Because many obese patients
also have other conditions that can adversely affect their health, physicians
should carefully monitor patients enrolled in weight-loss programs that include
weight-loss medications.
The findings of the study are consistent with the NIH Obesity Clinical Guidelines,
which recommend that weight loss medications be used in a supportive role to
a comprehensive program of behavioral treatment, diet therapy, and increased
physical activity. The NIH Obesity Clinical Guidelines state that the most successful
strategies for weight loss include calorie reduction, increased physical activity,
and behavioral therapy designed to improve eating and physical activity habits.
The Guidelines also recommend that physicians prescribe a regimen of lifestyle
therapy for at least six months before adding weight-loss medication to the regimen.
More information on the NIH Obesity Clinical Guidelines is available on the NIH
web site at http://www.nhlbi.nih.gov/guidelines/obesity/ob_home.htm.
According to data from the 1999 to 2000 National Health and Examination Survey
(NHANES), approximately 65 percent of Americans aged 20 years or older are overweight
with 31 percent of adults obese as defined by body mass index (BMI). BMI is a
calculation that takes into account both height and weight. Overweight is defined
as having a BMI of 25 to 29.9 kg/m2. Obesity is defined as having a BMI of 30
kg/m2 or higher. The NIDDK Weight-control Information Network fact sheet, Statistics
Related to Overweight and Obesity (http://win.niddk.nih.gov/statistics/index.htm)
provides more information.
NIDDK, part of the National Institutes of Health (NIH), conducts and supports
research on diabetes; endocrine and metabolic diseases; digestive diseases, nutrition,
and obesity; and kidney, urologic and hematologic diseases. Spanning the full
spectrum of medicine and afflicting people of all ages and ethnic groups, these
diseases encompass some of the most common, severe, and disabling conditions
affecting Americans.
The National Institutes of Health (NIH) — The Nation's Medical Research
Agency — includes 27 Institutes and Centers and is a component of
the U. S. Department of Health and Human Services. It is the primary Federal
agency for conducting and supporting basic, clinical, and translational medical
research, and it investigates the causes, treatments, and cures for both common
and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov. |