Strategies to Improve Long-Term Outcome 131(e.g., 5 to 7 kg over “ve years) but gastric bypass patients
commonly maintain 80% to 90% of their initial (i.e., “rst
year) weight losses (Balsiger et al., 2000).
Bariatric surgery entails both greater risks and greater
bene“ts than alternative treatments of obesity. The risks asso-
ciated with surgery can include postoperative complications,
micronutrient de“ciencies, and late postoperative depression
(National Institutes of Health, 1992). Among surgeons and
centers experienced in these surgical procedures, mortality
associated with bariatric surgery is approximately 0.5%
(L. Sjöstrom et al., 1995). These risks should be considered
in light of the documented bene“ts of bariatric sur gery.
Gastric bypass reduces or eliminates the major comorbid
conditions experienced by severely obese patients. Signi“-
cant improvements in hypertension, diabetes, dyslipidemia,
asthma, and sleep apnea are seen in the majority of patients
affected by these conditions (Kral, 1995; Long et al., 1994;
NIH, 1992). Moreover, a nonrandomized study showed a
signi“cantly lower mortality rate among morbidly obese dia-
betic patients who underwent gastric bypass surgery com-
pared to a matched group who did not (MacDonald et al.,
1997). Bariatric surgery also appears to prevent the develop-
mentof serious diseases that commonly occur in morbidly
obese patients. L. Sjöstrom et al. (1995) documented a three
to fourfold reduction in risk for hypertension and a 14-fold
reduction in the risk for diabetes. Finally, it should be noted
that signi“cant improvements in quality of life routinely ac-
company the large weight losses achieved by bariatric
surgery patients (NIH, 1992).
STRATEGIES TO IMPROVE
LONG-TERM OUTCOME
With the exception of surgery, virtually all treatments for
obesity show limited long-term effectiveness. Indeed, after
reviewing the outcome of all nonsurgical treatments of obe-
sity, the Institute of Medicine (Thomas, 1995) concluded
that •... those who complete weight-loss programs lose
approximately 10% of their body weight, only to regain two
thirds of it back within one year and almost all of it back
within 5 yearsŽ (p. 1).
What accounts for such disappointing outcomes? Poor
maintenance of weight loss seems to stem from a complex in-
teraction of physiological, environmental, and psychological
factors. Physiological factors, such as reduced metabolic rate
(Dulloo & Jacquet, 1998; Ravussin & Swinburn, 1993),
adaptive thermogenesis (Leibel, Rosenbaum, & Hirsch,
1995; Stock, 1999), and increased adipose tissue lipoprotein
lipase activity (Kern, 1997; Kern, Ong, Saffari, & Carty,
1990), prime the dieter to regain lost weight. Continuous
exposure to an environment rich in tasty high-fat, high-
calorie foods (Hill & Peters, 1998), combined with a dieting-
induced heightened sensitivity to palatable foods (Rodin,
Schank, & Striegel-Moore, 1989), further predisposes the
individual to setbacks in dietary control.
This challenging combination of physiological and envi-
ronmental barriers makes long-term success a very dif“cult
proposition. Thus, it is not surprising that most overweight
individuals experience dif“culties after the completion of
weight-loss treatment. In addition, from the patient•s view-
point, the most satisfying aspect of treatment, weight loss,
usually ends with the termination of intervention. As a re-
sult, many perceive a high behavioral •costŽ associated with
continued efforts at weight control precisely at the same
time they are experiencing diminished •bene“tsŽ in terms of
little or no additional weight loss. A regaining of weight
often leads to attributions of personal ineffectiveness that
can trigger negative emotions, a sense of hopelessness, and
an abandonment of the weight-control effort (Goodrick,
Raynaud, Pace, & Foreyt, 1992; Jeffery, French, & Schmid,
1990).
Over the past 15 years, researchers have examined a wide
array of strategies with the goal of improving long-term out-
come in obesity treatment. These include very low-calorie
diets, extended treatment, skills training, monetary incen-
tives, food provision, peer support, exercise/physical activity,
and multicomponent posttreatment programs (see Table 6.5).
In the following sections, we review the effectiveness of
these approaches to improving long-term outcome.Very Low-Calorie DietsIf obese patients lose larger amounts of weight during initial
treatment, will they keep off more weight in the long run?
Investigations of very low-calorie-diets (VLCDs) provide a
partial answer to this question. VLCDs are portion-controlled,
very low energy ( 800 kcal/day), high protein diets, often de-
livered in liquid form. Losses of 20 to 25 kg (approximately
20% of initial body weight) are usually incurred following use
of VLCD. A review of seven studies comparing VLCDs with
lifestyle interventions (using 1200 to 1500 kcal/day diets)
showed that participants treated with a VLCDinitiallylost
nearly twice as much weight as those in lifestyle interventions
(Wadden & Foster, 2000). However, at the conclusion of
VLCD treatment, a rapid regaining of weight usually occurs
such that the long-term weight losses produced by VLCDs are
no greater than those obtained by lifestyle interventions (e.g.,
Wadden, Foster, & Letizia, 1994).