Introduction
Endoscopic bariatric therapies (EBTs) are evolving to be an effective minimally invasive
treatment option for patients with obesity and associated comorbidities [1]
[2]. EBT is performed either as a primary stand-alone therapy or as a bridge treatment
before surgery [3]. Currently, three US Food and Drug Administration-approved devices are available
for endoscopic treatment of obesity, and a few more are under development [4]. Among them, intragastric balloons (IGBs) and endoscopic gastroplasty (EG) techniques
have gained wide popularity and acceptance.
Several studies have established the technical feasibility, reproducibility, safety,
and efficacy of IGBs and EG [5]
[6]
[7]
[8] ([Table 1]). However, considerable variation exists in short-term and long-term total body
weight loss outcomes [9]
[10]. At 12-month follow-up, Apollo Overstitch sutured gastroplasty (Overstitch; Apollo
Endosurgery, Austin, Texas, United States), was shown to achieve total body weight
loss (17.6 %) with the effect sustained up to 24 months (20.9 %) [11]. On the contrary, the total body weight loss with IGBs ranged between 11 % and 15%
at 6 months with a risk of weight regain after balloon removal [12]
[13]
[14]
[15]. Multiple factors, in addition to the anatomical and neuroendocrine signaling changes,
may have influenced the difference in weight loss outcomes [16].
Table 1
Summary of data published on each technique.
|
Procedure type (ref)
|
Publication (n)
|
Patients (n)
|
%TBWL-12 months (95 % CI)
|
SAE (%)
|
SAE needing surgery
|
|
Orbera [13]
[14]
|
8
|
8506
|
10 % (6.6 – 13.6 %)
|
1.5 %
|
0.1 %
|
|
ReShape Duo [15]
|
1
|
202
|
14.7 % (8.02 – 21.4)
|
0.03 %
|
16 %
|
|
POSE [20]
|
3
|
402
|
10.98 (3.48 – 18.48)
|
0.03 %
|
0.09 %
|
|
ESG [24]
|
9
|
1542
|
16.09 % (14.24 – 17.94)
|
1 %
|
21 %
|
In our prior experience treating 25 patients (body mass index [BMI] > 30 kg/m2) with Apollo ESG, we found that the number of contacts with the nutritionist and
psychologist during follow-up significantly predicted the weight loss at 1 year [17]. Currently, it is unclear if the weight loss results between different EBTs is related
to the technique or multidisciplinary team (MDT) follow-up or both. Most centers differ
in the nutrition and follow-up protocol and there is a lack of evidence comparing
weight loss outcome of different EBTs within an identical follow-up program.
Since 2011, our bariatric endoscopy unit has standardized EBT techniques, adopted
a structured post-procedure follow-up protocol, and performed a variety of EBTs. In
this study, we aimed to compare weight loss outcomes of different EBTs within the
same follow-up program and evaluated factors that predicted weight loss and follow-up
adherence at 1 year.
Patients and methods
Study design
We prospectively collected and retrospectively studied data from patients who underwent
EBTs at the Bariatric Endoscopy Unit of HM Sanchinarro University Hospital, Madrid,
between March 2012 and January 2017. The institutional review board approved the study.
All authors had access to the study data and reviewed and approved the final manuscript.
All the procedures were performed following the ethical principles detailed in the
Declaration of Helsinki and were consistent with the Good Clinical Practices recommendation.
Study patients
We included 1013 patients who received EBTs during this period. All the patients were
referred to our unit after failed conservative therapy at other centers. The EBTs
were offered as a self-pay procedure and not covered by health insurance. We discussed
the different endoscopic bariatric treatment options with the patient and explained
the risks, benefits, and cost (EG >IGB) of each procedure. Choice of EBT was decided
based on patient preference. We did not have a personalized or preferred treatment
approach based on patient profile. All the patients included paid the treatment expenses
upfront, and the cost of MDT follow-up was identical. We extracted data on demographics,
weight parameters, type of EBT, and compliance to follow-up from our obesity database
for analysis. All patients consented to the procedure. We excluded those who were
referred for EG after failed IGB.
Intervention
Procedure
The EBTs performed during this study included Intragastric balloon placement (Orbera,
Apollo Endosurgery, Austin, TX; ReShape Duo, Apollo Endosurgery, Austin, TX) and endoscopic
gastroplasty using Apollo Overstitch or Primary obesity surgery endoluminal (POSE,
USGI Medical, San Clemente, USA) ([Fig.1]). All the procedures were performed by the same endoscopist and were followed-up
by the same multidisciplinary team (nutritionist and psychologist). We have previously
described in detail our technique on different IGB placement, Apollo ESG, and POSE
in our prior publications [7]
[8]
[18]
[19]
[20]. We do not routinely perform repeat endoscopy to assess the integrity of the sutures
with the endoscopic gastroplasty procedures.
Fig. 1 Endoscopic image of 4 different EBTs. a Orbera IGB. b ReShape Duo IGB. c Apollo endoscopic sleeve gastroplasty. d POSE.
Follow-Up Schedule
Patients were followed-up weekly or biweekly post-procedure by a nutritionist, psychologist,
and physiotherapists. When their condition stabilized, we extended the visits to once
a month. We recommend achieving 24 clinic visits over 1 year irrespective of the procedure
type. The follow-up program comprised dietary instructions, psychological support,
physical activity, and a planned counseling schedule, as well as a timeline for future
visits.
Body requirements and individual taste preferences were taken into account while designing
the hypocaloric diets. Energy requirements were calculated from the Harris-Benedict
formula. Based on the type of physical activity, we decreased caloric intake by about
2.6 MJ/day to induce an approximate weight loss of between 0.5 and 1 kg/week. In the
first month after EG, we maintained patients on a strict liquid diet (4 weeks). We
subsequently escalated intake to semi-solid and solid food as tolerated. In the IGB
patients, we initiated a solid meal within 2 weeks. We used a Mediterranean type diet
in which distributions of principal components were as recommended by the Spanish
Society of Community Nutrition [21].
We devised an individualized exercise plan and avoided an increase in intra-abdominal
pressure during the first month. We encouraged walking in the initial phase and then
progressively increased exercise intensity. There were no other differences in the
follow-up plan between the two groups, and the patients were counseled to adhere to
follow-up even after balloon explantation.
Study outcomes
The primary outcome was to compare the weight loss results of four different EBTs
at 1 year. Our secondary outcome was to identify factors that predict weight loss
and follow-up completion at 1 year.
Study variable description
We collected information on the following variables.
-
Gender
-
Age: Continuous variable and we classified them into two groups (Group 1 ≥ 45 years;
Group 2 < 45 years)
-
Type of EBTs: We segregated them into IGB group (Orbera and ReShape Duo IGB), EG group
(Apollo ESG, and POSE)
-
Weight Parameters: We measured weight, height, and BMI at baseline and during each
follow-up visit. We classified them into two groups based on severity of obesity (Group
1 ≥ 40 kg/m2, and Group 2 < 40 kg/m2).
-
Attendance to follow-up: We defined it as the percentage of scheduled visits to which
the patient went during the first year of follow-up. We divided follow-up attendance
in the completion group into three tertiles to understand its relationship with the
weight parameters [17].
-
End of Treatment Response: We classified them into two groups. Completion group are
those who had weight results recorded at 1 year. Drop-out group are those who failed
to complete the 1 year recommended follow-up. Patients were considered drop-out if
they had no weight loss results recorded at 1 year irrespective of the prior follow-up
attendances.
-
Weight loss parameters: We measured %TBWL and %excess weight loss (%EWL) with the
four EBTs at the end of 1 year. We grouped them into those who achieved ≥ 10 %TBWL
and those who met ≥ 20 %TBWL.
Statistical analysis
We expressed continuous variables as mean ± standard deviation (SD) and categorical
variables as a percentage. Comparisons of means between groups were calculated using
the Mann-Whitney or Kruskal-Wallis test (for not normally distributed variables).
Bivariate analyses of proportionality of distribution of categorical variables were
estimated using the Chi-square test. We performed a linear regression analysis to
evaluate the relationship of age, gender, initial BMI, procedure type, and % follow-up
attendance on %TBWL at 1 year. We performed a logistic regression analysis to study
the association between age, sex, initial BMI, and procedure type on follow-up adherence
at 1 year. We used Kaplan-Meier survival curves to illustrate patient attrition over
treatment time. P < 0.05 was considered statistically significant. We analyzed the data analyses using
Statistical Package for the Social Sciences 19.0 software (SPSS Inc., Chicago, Illinois,
United States).
Results
Patient characteristics
We identified 1013 patients who underwent EBTs during the study period. We excluded
51 cases as they were treated using an alternative swallowable IGB (Elipse, Allurion
Technology, United States) device with a shorter follow-up duration (4 months). Among
the remaining 962 patients, we treated half (50 %, n = 481) using IGBs and the rest
with EG. We used Orbera balloon in 389 (40.4 %) and ReShape Duo IGB in 92 (9.6 %)
cases, and performed Apollo ESG in 247 (24.3 %) and POSE in 234 (25.7 %) patients,
respectively ([Table 2]). The mean number of follow-up visits to the MDT was 7.6 ± 5.3 (median-7; IQR-7;
range-0 to 36). Only half the patients (n = 480, 49.9 %) had weight loss results recorded
at 1 year ([Fig. 2]). The remaining patients dropped out from follow-up at a different time interval.
Characteristics of the study participants are detailed in [Table 3]. Mean age was 44.8 ± 10.6 years, and mean BMI was 37.8 ± 5.9 Kg/m2. The majority of participants were female (71.2 %, n = 691).
Table 2
Baseline characteristics of EBTs.
|
Variables
|
Orbera
|
Reshape Duo
|
Apollo
|
POSE
|
P value
|
|
Age
|
42.9 ± 11
|
42.3 ± 12.8
|
45.9 ± 9.6
|
47 ± 10.1
|
< 0.001
|
|
Sex
|
70.2 %
|
79.3 %
|
70.4 %
|
73.1 %
|
0.32
|
|
Initial BMI
|
37.6 ± 6.7
|
38.4 ± 5.2
|
38.3 ± 5.7
|
37.6 ± 4.8
|
0.052
|
|
BMI > 40 kg/m2
|
29.6 %
|
33.7 %
|
36.4 %
|
27.8 %
|
0.16
|
EBT, endoscopic bariatric therapy; BMI, body mass index
Fig. 2 Flowchart describing the study population.
Table 3
Characteristics of study groups.
|
Characteristics
|
Completion Group (n = 480)
|
Drop-out Group (n = 482)
|
P value
|
|
Age ± SD, years
|
45.3 ± 11.3
|
44.3 ± 10
|
0.04
|
|
|
45 %
|
55 %
|
|
|
|
52 %
|
48 %
|
|
|
Gender
|
|
|
0.01
|
|
|
44 %
|
56 %
|
|
|
|
52 %
|
48 %
|
|
|
Initial BMI ± SD, kg/m2
|
38.5 ± 5.8
|
37.2 ± 6
|
< 0.001
|
|
|
46 %
|
54 %
|
|
|
|
59 %
|
41 %
|
|
|
Procedure type
|
|
|
0.002
|
|
|
217 (45 %)
|
264 (54 %)
|
|
|
|
263 (55 %)
|
218 (45 %)
|
|
BMI, body mass index; IGB, intragastric balloon; EG, endoscopic gastroplasty
Weight loss results with four EBTs
Among the 480 patients who reached 1 year follow-up (completion group), 45 % were
treated with IGBs and 55 % using EG techniques. Overall mean TBWL, %TBWL and %EWL
of the bariatric program involving the four EBTs were 18 ± 11.9 kg, 16.3 ± 9.3 %,
and 51 ± 30.8 %, respectively. Ninety-one percent achieved ≥ 5 % TBWL (n = 436), 77 %
obtained ≥ 10 % TBWL (n = 370), and 31 % reached ≥ 20 % TBWL (n = 150). Among the
EBTs, Apollo ESG demonstrated significantly higher mean ± SD TBWL (19.5 ± 13 kg, P = 0.035), %TBWL (17.4 ± 10.2, P = 0.025), ≥ 20 % TBWL (36.7 %, P = 0.032) and had the highest percentage follow-up attendance at 1 year (59.3 ± 25.6 %,
P = 0.001) ([Table 4]). To better compare and synchronize with balloon removal, we analyzed results in
patients who completed follow-up at 6 months (n = 624) and found Apollo ESG achieved
significantly higher mean ± SD TBWL (17.7 ± 9.2 kg, P = 0.008), %TBWL (16.1 ± 17.4, P = 0.007), and higher percentage follow-up attendance (49.6 ± 27.5 %, P = 0.001) ([Table 5])
Table 4
Weight loss outcomes with different techniques at 1 year.
|
Outcomes
|
Orbera
(n = 151)
|
Reshape Duo
(n = 66)
|
POSE
(n = 113)
|
Apollo
(n = 150)
|
P value
|
|
Mean ± SD TBWL
|
18.7 ± 12.6
|
15.3 ± 8
|
16.6 ± 10.6
|
19.5 ± 13
|
0.035
|
|
Mean ± SD %TBWL
|
16.9 ± 9.3
|
14.4 ± 6.7
|
15.3 ± 8.7
|
17.4 ± 10.2
|
0.025
|
|
≥ 10 % TBWL
|
79.5 %
|
74.2 %
|
71.7 %
|
80 %
|
0.337
|
|
≥ 20 % TBWL
|
35.1 %
|
19.7 %
|
25.7 %
|
36.7 %
|
0.032
|
|
Mean ± SD %Attendance
|
56.3 ± 26.9
|
31.9 ± 23.8
|
25.1 ± 17.7
|
59.3 ± 25.6
|
0.001
|
TBWL, total body weight loss
Table 5
Weight loss outcomes with different techniques at 6 months.
|
Outcomes
|
Orbera
(n = 228)
|
Reshape Duo
(n = 53)
|
POSE
(n = 148)
|
Apollo
(n = 195)
|
P value
|
|
Mean ± SD TBWL
|
17.2 ± 9.8
|
13.5 ± 6
|
15.6 ± 8.3
|
17.7 ± 9.2
|
0.008
|
|
Mean ± SD %TBWL
|
15.7 ± 7.5
|
12.6 ± 4.9
|
14.5 ± 6.8
|
16.1 ± 7.4
|
0.007
|
|
> 10 % TBWL
|
82.2 %
|
75.6 %
|
71.6 %
|
83.1 %
|
0.135
|
|
≥ 20 % TBWL
|
37.2 %
|
24.4 %
|
24.2 %
|
37.7 %
|
0.071
|
|
Mean ± SD %Attendance
|
45.3 ± 26.9
|
37.4 ± 23.5
|
18.5 ± 15.9
|
49.6 ± 27.5
|
0.001
|
TBWL, total body weight loss
We analyzed the relationship between weight loss parameters (TBWL, %TBWL, %EWL) and
MDT follow-up. We classified attendance to MDT follow-up into three groups: low-attendance
(T1, attendance < 28 %), medium attendance (T2, attendance 28 %-57 %), and high attendance
(T3, attendance > 57 %) [17]. We found the magnitude of weight loss increased significantly in patients who achieved
high MDT follow-up attendance in the completion group at 6 months and 1 year. (P < 0.01) ([Fig. 3] and [Fig. 4]).
Fig. 3 Weight loss outcome based on percentage follow-up attendance at 12 months in the completion
group (n = 480). The best weight loss outcome was observed in the high-attendance
group.
Fig. 4 Weight loss outcome based on %follow-up attendance at 6 months in the completion
group (n = 624). The best weight loss outcome was observed in the high-attendance
group.
Predictive factors for weight loss and follow-up completion at 1 year
We performed a linear regression analysis, after controlling for study variables,
to identify predictive factors for %TBWL in the completion group (n = 480). We found
%follow-up attendance (B = 0.24, P < 0.001) and initial BMI (B = 0.31, P < 0.001) predicted higher %TBWL at 1 year. Type of EBT did not influence weight loss
at 1 year (B = 0.02, P = 0.72). These findings were identical when we performed the analysis at 6 months
(n = 624). Procedure type did not influence weight loss (B = 0.01, P= 0.72) ([Fig. 5] and [Fig. 6]).
Fig. 5 Kaplan-Meier curve indicating cumulative incidence of achieving > 10 %TBWL at time
of last contact (dropout) with the MDT team in the IGB and EG groups. Procedure type
did not influence weight loss results (0 = 0.83)
Fig. 6 Kaplan-Meier curve indicating the cumulative incidence of achieving > 10 %TBWL at
time of last contact (dropout) with the MDT team for the four different EBTs.
We performed a logistic regression analysis to identify factors that predicted follow-up
completion at 1 year in the entire cohort. We found gender (females adhered better),
initial BMI (higher BMI-higher adherence), procedure type (endoscopic gastroplasty-longer
follow-up), and %weight loss at 1 month (higher weight loss- longer follow-up) significantly
predicted follow-up completion at 1 year ([Table 6]). However, when analyzed at 6 months, type of procedure did not predict follow-up
adherence (P = 0.2).
Table 6
Logistic regression assessing predictive factors for follow-up completion in 962 patients.
|
Covariables
|
6-months
|
1 year
|
|
Exp (B)
|
95 % CI
|
P value
|
Exp (B)
|
95 % CI
|
P value
|
|
Gender
|
1.17
|
0.77 – 1.78
|
0.45
|
1.64
|
1.11 – 2.42
|
0.01
|
|
Age
|
0.99
|
0.9 – 1.01
|
0.67
|
1.004
|
0.99 – 1.02
|
0.63
|
|
Initial BMI
|
1.04
|
1.01 – 1.77
|
0.01
|
1.82
|
1.25 – 2.64
|
< 0.001
|
|
Procedure type
|
1.28
|
0.86 – 1.89
|
0.21
|
1.44
|
1.0 – 2.07
|
0.04
|
|
1-month %weight loss
|
1.07
|
1.01 – 1.14
|
0.02
|
1.134
|
1.07 – 1.20
|
< 0.001
|
Variables: Gender (male vs. female); age (continuous); initial BMI (continuous); procedure
type (IGB vs. EG)
BMI, body mass index; IGB, intragrastric balloon; EG, endoscopic gastroplasty
We performed additional analysis to identify variables associated with high attendance
to MDT (T3, attendance > 57 %), independent of treatment completion at 1 year. We
found initial BMI (B = 0.103, P = 0.012), female sex (B = 0.12, P = 0.002) and %weight loss at 1 month (b = 0.276, P < 0.001) but not procedure type (B = 0.02, P = 0.63) predicted high MDT attendance.
Discussion
We report 1 year weight loss outcome of four EBT techniques in a structured bariatric
program and present the predictive variables for better results. We found the Apollo
ESG demonstrated higher weight loss results at the end of 1 year. However, in regression
analysis, adherence to MDT follow-up predicted weight loss at 1 year independent of
procedure type. Only 50 % of patients completed follow-up, and among them, endoscopic
gastroplasty (Apollo ESG and POSE) promoted more compliance with follow-up appointments.
ESG is a minimally invasive, incisionless endoscopic treatment that functions by shortening
and narrowing the gastric volume using a series of full-thickness sutures placed from
the distal body to the fundus of the stomach. Weight loss achieved with ESG is related
to delay in gastric emptying, reduced hunger, and early satiety [16]. Prior studies have reported that ESG can achieve up to 17 % to 20 % TBWL at 12
and 24 months [7]
[22]
[23]. Weight loss results in our study are consistent with the published literature [24]. There is scant data comparing the outcome of different IGB to EG. A retrospective
study (n = 88), which is published only in abstract form, showed no significant difference
in %TBWL at 6 months and 1 year between EG and IGB [25]. Our results are in agreement with this finding. We showed that weight loss at 1
year was not dependant on type of procedure but was determined by follow-up attendance
([Fig. 3] and [Fig. 4]). We postulated that frequent interaction with the MDT might have provided an opportunity
to identify "at risk of failure" patients and intervene at an early stage. Besides,
the psychological counseling and motivation of early responders may have promoted
sustained weight loss at 1 year.
Despite its significance, non-adherence and loss to follow-up is still an unresolved
problem with many obesity treatments [26]
[27]. We observed that half the patients were lost to follow-up at 1 year. Our drop-out
rates were similar to those described in bariatric surgical series and with conventional
therapies [28]
[29]
[30]. Surgical studies have identified several variables for long-term success but have
a limited description of follow-up compliance. In the current study, we found that
EG procedure (Apollo ESG, POSE), female sex, and high initial BMI predicted higher
follow-up adherence at 1 year. It is understandable that EG, a more lasting treatment
option, promoted more follow-up adherence than the temporary IGBs, which are usually
removed at 6 months. However, the finding that high BMI, independent of the patient's
age, predicts adherence is in contrast to published studies. In fact, among bariatric
surgical cases, high BMI and advanced age are considered as poor predictors for treatment
compliance [28]
[31]
[32]. We are uncertain about the reason for this discrepancy. The cohort of patients
with high BMI who choose EBT are those who declined surgery because of its invasiveness
and risk. We believe these patients are different from bariatric surgical patients
and that they are more motivated to achieve results with a less invasive treatment
option. Increased adherence to follow-up observed among patients who achieved significant
weight loss at 1 month lends support to this hypothesis. Also, achievement of early
desired weight loss in the low BMI group may have given them confidence to self-manage
their condition and drop-out from follow-up.
Our study has several strengths. It represents one of the largest bariatric endoscopy
cohorts to date that has the weight loss outcome recorded for different EBTs at the
end of 1 year. Performance of the procedures by the same endoscopist eliminated technique-related
bias. Most centers tend to specialize in one technique and focus on performing only
a specific type of EBT. Also, they differ considerably in their nutritional plan and
follow-up protocol. Thus, to study and compare the outcome of different EBTs from
a heterogenous bariatric endoscopy program may be difficult. We have standardized
the follow-up program, built an MDT team with experience in bariatric endoscopy care,
and have demonstrated the importance of the MDT program in achieving weight loss at
1 year. We have also added new information on predictive factors for weight loss and
follow-up compliance in the EBT cohort, which were previously less described.
Our study has certain limitations which are inherent to a retrospective analysis.
The study population was mainly Spanish, and all the procedures were performed by
a single endoscopist in a single center. Reproducibility of similar results in other
centers needs to be studied. Although our post-procedure follow-up was standardized
across different EBTs, there was a slight variation in nutrition escalation during
the first month between IGBs and EG. It possibly could have contributed to excess
weight loss with EG at 1 month but is unlikely to have influenced the outcome at 1
year. We are uncertain whether the demonstrated benefit with adherence to MDT follow-up
is a reflection of the true success of our follow-up protocol or the motivation status
of the patients. Although challenging to differentiate, our prior experience, and
results from bariatric surgical series provide support for the importance of standardized
follow-up [17]
[33]. We did not evaluate some technical factors, such as suture pattern, number of sutures
placed and patient-related factors such as educational status, economic status, comorbidities,
prior pharmacotherapy, and mental health in predicting weight loss and compliance
to follow-up at 1 year. We could not obtain this information from our database. However,
available studies on different ESG patterns have reported no significant difference
in weight loss. Similarly, the evidence assessing the role of other parameters in
the bariatric surgical series has only yielded conflicting results [31]
[32]
[34]
[35]. In our previous study, we did not find any difference between presence of comorbidities
and treatment completion [27]. A prospective study assessing the relevance of these variables in EBT patients
ought to be performed.
Conclusion
In summary, all four EBTs are effective in achieving weight loss within a standardized
bariatric endoscopy program at 1 year. In particular, endoscopic gastroplasty procedures
(Apollo ESG, POSE) promote higher adherence to MDT follow-up than IGB. Careful monitoring
is required in order for low-responder-profile patients (male, BMI < 40 kg/m2, and less 1-month %TBWL) to achieve good results. Our study provides insight on the
importance of MDT follow-up and centers planning to establish a bariatric program
should focus on building a robust MDT and not just focus on the procedures alone.
