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Liposuctie helpt obese vrouwen niet.
Mensen met overgewicht
hebben geen baat bij liposuctie als ze de kans op diabetes, hypertensie en
hartziekten willen verkleinen. Ze zullen gewoon op de ‘ouderwetse’ manier
moeten lijnen, concluderen onderzoekers van Washington University in the New
England Journal of Medicine van 17 juni.
De
studie beschrijft de medische conditie van vijftien obese vrouwen, bij wie
ongeveer 10 kilo abdominaal vet per persoon werd verwijderd. Van de vijftien
vrouwen hadden acht vrouwen een normale glucosetolerantie en zeven vrouwen
hadden diabetes type 2. Na tien tot twaalf weken bleek de insulinegevoeligheid
van de lever, de spieren of het vetweefsel onveranderd ten opzichte van vóór
de ingreep. Ook bleef het lipidengehalte in het bloed, de bloeddruk en de
hoeveelheid markers voor ontstekingen gelijk.
Bij liposuctie wordt subcutaan vet
verwijderd, maar de vetcellen in andere weefsels, zoals de lever en het hart,
blijven aanwezig. De onderzoekers denken dat daarom het metabolisme van de
proefpersonen niet verbeterde. Door diëten ontstaat echter een negatieve
energiebalans, waardoor het aantal en de grootte van vetcellen afneemt en er wel
metabool voordeel te behalen is.
De onderzoekers zijn echter niet negatief over liposuctie. Want al is
liposuctie geen oplossing voor hart- en vaatziekten bij obesitas, deze
resultaten geven volgens hen in ieder geval aan dat het wegzuigen van een grote
hoeveelheid overtollig vet veilig is.
Liposuction Won't Remove Fat's Health Risks
Surgery no fix for preventing diabetes, heart
woes
The rapid removal of even
large amounts of body fat via liposuction is no quick fix for obesity-related
conditions like diabetes or cardiovascular disease, researchers say.
Surgeries that rid patients of
an average 22 pounds of fat did nothing to change their insulin sensitivity,
blood pressure readings or cholesterol levels, according to a study published in
the June 17 issue of the New England Journal of Medicine.
"There was no sign that
liposuction caused adverse health effects from a medical perspective, but
patients didn't gain any benefit, either," said Dr. David E. Kelley,
director of the Obesity Research Center at the University of Pittsburgh who
wrote a commentary on the study for the journal.
According to the American
Society of Plastic Surgeons, more than 320,000 liposuction procedures were
performed last year in the United States. For most Americans, liposuction
"is still perceived as a cosmetic procedure," Kelley said.
But fighting obesity can also
help prevent killer diseases like diabetes and heart disease. "Fat affects
metabolism, appetite, everything," Kelley said. "So the thought has
always been, 'What would happen if we suddenly removed a very large portion of
fat?'"
Now, researchers led by Dr.
Samuel Klein of Washington University School of Medicine in St. Louis believe
they've answered that question.
For their study, Klein and his
colleagues used liposuction on 15 obese women to remove an unusually large
amount of abdominal fat from each -- about 22 pounds on average, totaling nearly
20 percent of their total body fat. Eight of the patients were diagnosed with
type 2 diabetes; the other seven showed no signs of the disease.
The researchers compared each
woman's post-liposuction insulin sensitivity, blood pressure, cholesterol levels
and other common disease risk factors to readings taken before surgery.
According to Klein, "none
of those risk factors improved, despite removing these large amounts of
fat."
So if liposuction doesn't
affect disease risk factors, how does shedding fat by non-surgical means -- such
as diet and exercise -- improve health?
The answer, Klein said, lies
in the size of each fat cell.
"We think that when you
lose fat by dieting, you undergo a negative energy balance, consuming fewer
calories than you burn up. This causes your fat cells to shrink to a smaller
size," Klein explained.
"But with liposuction,
you remove fat cells without shrinking any of the remaining fat cells left
behind," he said.
Those oversized,
post-liposuction fat cells continue to act as they always have, raising blood
pressure and straining the body's response to insulin.
On the other hand, "diets
and exercise also cause you to reduce fat deep within your muscle tissue and
liver," Klein said. "Inside of those tissues are lipid droplets that
are associated with normal metabolism and insulin resistance. When you reduce
fat via diet and exercise, you reduce the fat content in those non-fat tissues,
too."
To the dismay of those hoping
for a medical boost from fat-removing surgery, none of this occurred after
liposuction.
"Unfortunately, we're
back to the same old boring advice -- it's not how much fat you lose but how you
lose it that's important," Klein said.
Losing fat the old-fashioned
way, by eating sensibly and working out, "is key to improving your
metabolic health," he added.
Still, liposuction's cosmetic
results might give some patients the mental jump-start they need to eat better
and get back on the treadmill.
"Some of the [health]
benefit observed in previous studies with smaller amounts of liposuction had to
do with the fact that people who had the procedure then began to change their
lifestyle," Klein said. (juni 2004)