Metabolic and Weight Loss Effects of Long- Term Dietary Intervention in Obese Patients: Four-Year Results

SHORT COMMUNICATION
Metabolic and Weight Loss Effects of Long-
Term Dietary Intervention in Obese Patients:
Four-Year Results
Marion Flechtner-Mors,* Herwig H. Ditschuneit,* Timothy D. Johnson,† Mark A. Suchard,†‡ and
Guido Adler*
Abstract
(mean
SEM) for Group B. Both groups showed signifi-
FLECHTNER-MORS,
MARION,
HERWIG
H.
cant improvement in blood glucose and insulin (p
0.001),
DITSCHUNEIT, TIMOTHY D. JOHNSON, MARK A.
but only Group B showed significant improvement in tri-
SUCHARD, AND GUIDO ADLER. Metabolic and weight
acylglycerol and systolic blood pressure compared to base-
loss effects of long-term dietary intervention in obese pa-
line values (p
0.001).
tients: Four-year results. Obes Res. 2000;8:399 – 402.
Discussion: Providing a structured meal plan via vitamin-
Objective: To investigate the contribution of meal and snack
and mineral-fortified liquid meal replacements is a safe and
replacements for long-term weight maintenance and risk
effective dietary strategy for obese patients. Long-term
factor reduction in obese patients.
maintenance of weight loss with meal replacements can
Research Methods and Procedures: Prospective, random-
improve certain biomarkers of disease risk.
ized, two-arm, parallel intervention for 12 weeks followed
by a prospective single-arm 4-year trial in a University
Key words: dietary treatment, meal replacements, long-
Hospital clinic. One hundred patients,
18 years old and
term weight loss, biomarkers for disease
with a body mass index
25 and
40 kg/m2, were
prescribed a 1200 to 1500 kcal/d control diet (Group A) or
an isoenergetic diet, including two meal and snack replace-
Introduction
ments (vitamin- and mineral-fortified shakes, soups, and
There is general concern that weight loss in obese pa-
bars) and one meal high in fruits and vegetables (Group B).
tients is only transient, and therefore, future efforts at
Following a 3 months of weight loss, all patients were
weight control should be aimed at prevention of weight
prescribed the same energy-restricted diet (1200 to 1500
gain. Recent reports, however, have demonstrated long-
kcal) with one meal and one snack replacement for an
term successes in weight loss (1–3). These observations plus
additional 4 years.
the documentation that a minimal weight loss (5% to 10%
Results: All 100 patients were evaluated at 12 weeks. Mean
of initial body weight) can have profound health benefits (4)
percentage weight loss was 1.5
0.4% and 7.8
0.5%
indicate a need for health professionals to utilize all effec-
(mean
SEM) for Groups A and B, respectively. At 12
tive methods to promote healthy weight loss in overweight
weeks systolic blood pressure, plasma triacylglycerol, glu-
or obese individuals.
cose, and insulin concentrations were significantly reduced
The subject of the present study is the 4-year follow-up of
in Group B, whereas no changes occurred in Group A. After
patients who were originally instructed on the use of meal
4 years, 75% of the patients were evaluated. Total mean
replacements for weight loss and weight maintenance (5).
weight loss was 3.2
0.8% for Group A and 8.4
0.8%
This report provides follow-up data of body weight and
biomarkers of disease risk for 75% of the original patients
who continued the meal replacement program as a means of
reducing energy intake.
Submitted for publication October 18, 1999.
Accepted for publication in final form February 11, 2000.
*Department of Internal Medicine, University of Ulm, Germany and †Department of
Biomathematics, UCLA, Los Angeles, California.
‡Recipient of a Howard Hughes Medical Training Grant.
Materials and Methods
Address correspondence to Herwig H. Ditschuneit, MD, University of Ulm, Department of
Patients were referred by their physicians to the Univer-
Internal Medicine, Robert-Koch-Strasse 8, D-89081 Ulm, Germany. E-mail: herwig.
sity of Ulm Obesity Center because of past dissatisfaction
ditschuneit@medizin.uni-ulm.de
Copyright © 2000 NAASO.
with a standard energy-restricted diet plan for
3 months.
OBESITY RESEARCH Vol. 8 No. 5 Aug. 2000
399

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Effects of Long-Term Dietary Intervention in Obese Patients, Flechtner-Mors et al.
The study was carried out according to the principles of the
of the time points. To adjust for multiple comparisons, a test
Helsinki Declaration, and the Freiburg Ethics Committee
was considered significant if its p value was less than 0.01
International (Freiburg, Germany) approved the protocol.
as opposed to the traditional 0.05.
Individuals with a history of, or presence of, significant
disease, endocrine disorders, psychiatric disorders, alcohol
or drug abuse, or abnormal laboratory test results of clinical
Results
significance were excluded. In addition, women were ex-
Seventy-five percent (60 female and 15 male patients) of
cluded if they were lactating, pregnant, or wished to become
the original study population comprise the analyses in this
pregnant.
report. Figure 1 represents the average percentage weight
One hundred patients agreed to participate in the study.
change for Groups A and B over time. There were no gender
They received no financial compensation other than free
differences in percentage weight loss; hence, these data
supplies of meal replacement products. The experimental
were combined for each of the original treatment groups.
design and results of the 2-year intervention have been
During 4 years of weight maintenance, average weight
previously reported (5). Patients were encouraged to main-
loss of Group B was consistently greater than Group A (p
tain their usual level of physical activity and received
0.001). Both groups showed a transient increase in body
monthly instruction in behavior modification by the dieti-
weight at month 41. A matched pairs analysis (matching for
tian. The study design consisted of a weight loss period
group, gender, and length of time a re-entrant subject was
(Phase I) of 3 months and a weight maintenance period
missing) found no significant body weight differences be-
(Phase II) of 48 months. Before study initiation, patients
tween the re-entry subjects and those who stayed in trial.
were randomly assigned to one of two groups (Group A or
Those subjects in Group A with regular visits lost an aver-
Group B). The initial demographics were not different be-
age of 3.2
4.9%, whereas the transient drop-outs lost
tween the study groups (5). Average age and body mass
3.0
3.0%. In Group B, completers lost an average of
index of the 21 male and 79 female patients was 45.2
8.4
5.0%, whereas transient drop-outs lost 8.5
5.0%.
10.1 years and 33.6
3.6 kg/m2
The subjects also showed no increase in weight from the
, respectively.
time of drop-out to the time of re-entry. An examination of
During Phase I, patients in Group A were prescribed per-
individual patient records showed that those patients who
sonalized menus. The diet was composed of 1200 to 1500 kcal
had gained the most weight ( 3 kg between months 39 and
(19% to 20% of energy was as protein, 48% to 54% of energy
41) coincided with their summer vacation and the time that
as carbohydrate, and 25% to 34% of energy as fat). Three
they re-entered the study (month 41).
meals and two snacks were recommended. Group B was also
prescribed similar self-selected diets, except two of three daily
meals were replaced by diet shakes (Slim Fast Foods Co., West
Palm Beach, FL). The third meal consisted of 600 to 900 kcal
with 30 to 45 g of protein. Each meal replacement contained
200 to 220 kcal, 14.0 to 17.0 g of protein, 27.0 to 33.5 g of
carbohydrate, 5.0 to 6.6 g of fat, and 4.5 to 6.5 g of dietary fiber
with vitamin and mineral fortification. Food exchange lists and
food diaries were used to equalize energy and protein intake
between groups.
During Phase II, patients received the same dietary in-
struction, i.e., to replace one meal and one snack with the
energy-controlled meal and snack replacement. The energy
content of the prescribed diets was the same for both groups.
At the end of the second year (month 27), 63 of the
original 100 patients completed the study. By month 37, a
total of 58 patients continued to keep their monthly appoint-
ments. Thirty-two of the 42 patients who had left the study
were located. Twenty-two agreed to re-enter the weight
Figure 1. Mean (
SEM) percentage change from initial body
control program between months 37 and 41.
weight in patients during 51 months of treatment with an energy-
At scheduled intervals, blood pressure, anthropometric
restricted diet (1200 to 1500 Kcal/d). Data were analyzed on an
and laboratory measurements, and side effects were re-
available case basis. Patients received either a conventional ener-
corded. Blood samples and analyses were as reported (5).
gy-restricted diet (control Group A,
) or a diet with two meal
Weight loss over time was evaluated using generalized
and snack replacements (Group B, ‚) for 3 months. During
estimating equations (GEE) (6 – 8). Student’s t test was used
the remaining 4 years, all patients received one meal and snack
to make group comparisons of these measurements at each
replacement daily.
400
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Effects of Long-Term Dietary Intervention in Obese Patients, Flechtner-Mors et al.
Table 1. Anthropometric and biochemical measurements at baseline, 2 and 4 years after treatment
Baseline
3 months
27 months
51 months
Measurements*
(n
100)
(n
100)
(n
63)
(n
75)
Body weight (kg)†‡
Group A
92.7
10.8§
91.4
11.6
85.0
11.8¶
88.6
11.0¶
Group B
92.6
13.7
85.5
13.4¶
82.2
13.4¶
83.1
13.3¶
SBP (mm Hg)**
Group A
140
14
141
16
138
13
139
15
Group B
139
15
130
13¶
124
12¶
126
13¶
DBP (mm Hg)**
Group A
83
6
82
5
80
6
80
7
Group B
82
6
80
5
78
5¶
78
6
Triacylglycerol (mM)†**
Group A
2.13
1.34
2.15
1.50
1.77
0.62
1.44
0.42
Group B
2.23
1.24
1.75
1.09¶
1.40
0.49¶
1.29
0.32¶
Cholesterol (mM)†
Group A
6.01
0.94
5.84
1.00
5.69
0.60
5.58
0.52
Group B
5.83
1.01
5.79
0.89
5.35
0.95
5.37
0.45
HDL-cholesterol (mM)†
Group A
1.27
0.41
1.24
0.31
1.18
0.17
1.21
0.12
Group B
1.31
0.41
1.30
0.44
1.39
0.77
1.26
0.16
Blood glucose (mM)
Group A
5.05
0.85
5.07
0.79
4.52
0.42¶
4.40
0.34¶
Group B
4.97
0.87
4.58
0.74
4.40
0.39¶
4.37
0.32¶
Insulin (pM)
Group A
134.6
50.4
139.1
63.2
98.8
30.0¶
92.6
17.1¶
Group B
132.0
53.1
84.9
30.4¶
81.8
30.2¶
82.5
22.4¶
* SBP, systolic blood pressure; DBP, diastolic blood pressure.
† GEE gender effect; p
0.01.
‡ GEE quadratic time effect; p
0.01.
§ Values are means
SD.
¶ Significantly different from baseline; p
0.01 (paired t test).
** GEE treatment effect; p
0.01.
Gender, group, time, and time squared plus interactions
Table 1 summarizes the changes in other study param-
were fit with the GEE model. No interactions were signif-
eters during the 4 years. Expressed as kilograms of
icant. At 4 years, both groups exhibited a significant weight
weight loss, there were gender differences (males lost
reduction from their baseline weight. There was a signifi-
more weight than females) that were not present when
cant group effect in which Group B had a greater percentage
weight loss was based on a percentage of initial body
change from baseline for all time points. This significance
weight. With minimal weight loss at 2 and 4 years,
was due to the difference in the initial weight loss observed
glucose and insulin were significantly reduced over time
at the completion of the first 3 months.
in Groups A and B (paired t test, p
0.01). Group B
At the completion of the study, 14 patients had lost more
showed significant reductions in systolic blood pressure
than 10% body weight, 28 patients lost 5% to 10%, and 25
and triacylglycerol when compared to baseline (paired t
patients lost 0% to 5% body weight compared to baseline.
test, p
0.01). GEE analyses showed that improvements
Eight of the 75 patients had gained an average of 2.4
1.8 kg
in biomarkers during the first 3-month period were main-
compared to their baseline weight; all were in Group A.
tained for the next 4 years (no time trend effects). The
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Effects of Long-Term Dietary Intervention in Obese Patients, Flechtner-Mors et al.
GEE found significant gender differences for high-
Acknowledgments
density lipoprotein-cholesterol, triacylglycerol, and total
This study was supported in part by Slim Fast Foods Co.,
cholesterol.
West Palm Beach, FL.
No adverse events were reported.
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