to Chapter Index
on Fen-Phen and Heart-Valve Problems
Two recent studies are adding to the data concerning fen-phen and
heart-valve problems. These studies should offer some reassurance
to patients who took this combination of weight-loss drugs.
Researchers from Harvard
Medical School evaluated echocardiograms performed on 226 people
who took fen-phen as part of a long-term study from September 1994
to September 1997. Shortly after the manufacturers voluntary
withdrawal of fen-phen, the medications were stopped and the patients
underwent testing to determine if any heart-valve problems had
developed. The echocardiograms showed that not one patient had
severe valvular disease. Mild leaking of the aortic valve was detected
in 12 patients, and three patients exhibited moderate aortic-valve
a total of 15 (6.6%) patients. Three subjects (1.3%) had moderate
leaking of the mitral valve. To compare the rate of heart-valve problems
in these patients to the rate one might expect to see in the general
population, investigators turned to data collected as part of the
Framingham Heart Study (the long-term epidemiological study being
conducted in a Boston suburb). They found nearly the same rates of
aortic- and mitral-valve leaking in the Framingham volunteers as
in the diet-drug study participants.
A second study published
in the November 23, 1999, issue of the American Heart Association
journal, Circulation, suggests that heart-valve abnormalities
in individuals who took dexfenfluramine (Redux) may dissipate.
Although study findings did link the drug to mild aortic-valve
disease and moderate mitral-valve problems, it also noted that
valve problems might eventually go away after drug use is stopped.
to spot heart-valve abnormalities, investigators evaluated 223
patients who had taken dexfenfluramine for an average of seven
months. The tests were performed an average of 8.5 months after
the participants stopped taking the drug. None of the former dexfenfluramine
users was found to have severe mitral valve disease or moderate
(or worse) aortic-valve disease, but 7.6% had either mild aortic-valve
disease or moderate mitral-valve problems. People who had stopped
treatment less than eight months before the echocardiogram were
twice as likely to have valve problems than those who had been
off dexfenfluramine for longer, suggesting the problem regresses.
Could it be that these
diet pills are safe after all? An editorial in the Journal of
the American College of Cardiology accompanied publication
of the Harvard study and asked whether there was adequate proof
of any increase in risk from fen-phen. No one is ready to go so
far as to suggest that these drugs should return to the market,
but a reasonable conclusion at this point is that there is an increased
risk of heart-valve problems, though the risk is probably quite
Regardless of the relative
risks and merits of fen-phen and of diet drugs in general
weight loss remains a problem that cannot be solved by any "magic
bullet." Medications may help a little in some patients, and
surgical solutions might be considered for severely overweight individuals.
However, for most of us, regular exercise and careful attention to
how many calories we eat remain the best strategies for successful
and lasting weight loss.
Journal of the American
College of Cardiology, Vol. 34, No. 4, pp. 115358.
Circulation, Vol. 100, No. 21, pp. 216167.
Health Burden of a Few Extra Pounds
According to an extensive study conducted by the American Cancer
Society, even being moderately overweight adds a significant
burden to your health. This research looked at the relationship
between body-mass index and the risk of death. It also examined
the influence of smoking, disease, race, and age on the weight-related
Body-mass index (BMI) combines height and weight measures to
gauge body mass. It is calculated by dividing your weight in
kilograms by the square of your height in meters. The simplest
way to calculate your BMI is to use a table that lists the
BMI for various weights and heights. (Check
The study investigators followed more than one million adults
between 1982 and 1996 and found that being moderately to severely
overweight greatly increases a persons chance of early
death from cancer, cardiovascular disease, and other illnesses.
Smoking and the presence of disease exacerbated this risk.
The lowest risk of death was associated with BMIs of 23.5 to
24.9 in men and 22.0 to 23.4 in women. Death rates then increased
as BMI increased. Even exceeding the upper end of the ideal
range by just a point or two appeared hazardous. The risk of
death from cardiovascular disease increased significantly in
men after a BMI of 26.5 and in women after 25.0 in men. And
the most obese white men and women (35+ BMI) were at least
twice as likely to die than their healthy cohorts. For instance,
a 5 ft. 9 in. male weighing 150 pounds has a BMI of 22. Add
just 30 lbs. to this person, and the BMI increases to 27, already
raising his health risks. At a 35 BMI, our 5 ft. 9 in. male
would weigh 240 pounds, and have increased his risk of dying
from cancer by 40% and cardiovascular disease by almost 100%.
Smoking and the presence of disease decreased the chance of
survival regardless of the subjects BMI.
Black Women proved the exception. Even the heaviest black women
saw only a 2030% increase in their risk of death opposed
to the nearly 100% increase in risk for similarly overweight
white women. This confirms the findings of previous studies,
and could be related to how differences in how the two groups
of women store and process fat.
The studys conclusion regarding the health effects of
extreme leanness is more controversial. While subjects with
BMIs under 18.0 experienced a moderately higher risk of death,
researchers believe this was more likely a function of an unrecognized
disease that resulted in lower body weight, rather that being
Debating the consequences of extreme leanness is academic.
Only 7.7% of the US population have BMIs lower than 20. Obesity,
however, is a public health threat. Nearly one- third of Americans
are moderately overweight (25.0 to 29.9 BMI) and almost one-
quarter are significantly overweight (30+ BMI). For more information
on obesity and approaches to weight loss, see page 853 of the
Family Health Guide.
for Severe Obesity
Two recent studies offer some hope for people who suffer from "clinically
severe obesity" (generally, a body mass index greater
than 40). For these people, whose weight poses serious health
risks, conventional diet and drug interventions are usually
unsuccessful. A last resort has been surgery to limit the number
of calories the body absorbs. But there have always been concerns
about the benefits versus the risks of surgery. Two procedures,
the Roux-en-Y gastric bypass and adjustable laparoscopic gastric
banding, each appear highly effective at promoting weight loss
in obese individuals.
In the Roux-en-Y gastric bypass procedure, surgeons divide
the patients stomach in two and create a small pouch
from the upper stomach. They then connect the small intestine
directly to this pouch, bypassing the rest of the stomach.
When the patient eats or drinks, the food passes from the esophagus
into the small pouch, which can hold only two to three ounces.
Because the pouch is so limited, the person feels full and
satisfied after eating only a small amount of food.
In a study conducted through the Mayo Clinic, surgeons performed
the gastric bypass procedure on obese patients and found that
after one year, the patients followed up had lost 68% of their
excess body weight. This weight loss remained fairly consistent
over four years. Many patients also reported that their appetites
had decreased. As an added benefit, a number of individuals
were able to reduce their high blood pressure, diabetes, and
anti-inflammatory medications. Yet some patients in the study
suffered complications from the surgery, such as wound infection,
hernias, and bowel obstruction. Despite this, the procedure
proved to be successful overall. After three years, 93% of
the patients contacted were satisfied with the results.
Traditionally, gastric bypass is performed through a long incision
in the patients abdomen. Doctors at the Lahey Clinic
have eliminated the need for the long incision through the
use of laparoscopic techniques during surgery. The surgeons
make six half-inch-long incisions in the abdomen through which
they can use surgical instruments and a laparoscope to view
the abdominal cavity. The Lahey Clinic reports that this technique
results in weight loss similar to the traditional surgical
technique, yet is safer and less invasive patients recover
more quickly and do not have the risk of complications associated
with a long incision.
The other procedure for obesity that boasts good results is
adjustable laparoscopic gastric banding. With this technique,
surgeons use a laparoscope to place an adjustable silicone
band around the stomach, forming two pouches. As with the bypass
technique, patients with the band feel full after eating a
small amount of food because the first pouch of the stomach
is small. In addition, the narrow passageway between the two
pouches slows down the transfer of food. Doctors can use radiography
to view the condition of the band and, if needed, can adjust
the size of the passageway between the two pouches by injecting
or aspirating a saline solution into a tube connected to the
In a Swiss study, patients who underwent the banding procedure
lost an average of 14% of their total weight six months after
the procedure and 18% after twelve months. These results sound
great, but complications, such as problems with the band, were
frequent, occurring in 34 out of 98 patients. Despite that,
the study claims that complications led to unsatisfactory weight
loss in only one of the patients. Nineteen other patients did
not lose significant amounts of weight as a result of poor
As with any weight loss treatment, both gastric bypass and
banding surgery require that the patient adopt new eating habits.
Physicians must also monitor these patients to make sure that
they do not develop vitamin and mineral deficiencies. But given
the apparent success of each technique, surgery for clinically
severe obesity may be an attractive alternative to diet and
drug intervention, despite the risks involved.
October 2000 Update