LA VIDA EN UN PUEBLO INDÍGENA DE GUATEMALA

A finding from the scoping review (Chapter 2) was that severely obese adolescents were often being considered for pharmacotherapy or bariatric surgery (NICE, 2006) yet it s use e ai s o te tious (Woolford et al., 2002) and under researched (Sachdev et al., 2014). With treatment paradigms entrenched in facilitating lifestyle change (Chapter 1 and Chapter 2), novel treatments that combine multidisciplinary lifestyle intervention (NICE, 2014) with a less invasive treatment (compared with bariatric surgery) such as a temporary aid are warranted. One such strategy is the use of Intra- Gastric Balloons as an adjunct to a lifestyle behavioural support programme.

4.1.1 Intra-gastric balloons (IGB)

Intra-gastric balloons (IGB) were first proposed as an aid for weight loss in adults more than 20 years ago (Imaz et al., 2008). Its primary objective was for the treatment of obese patients who had exhausted all clinical treatment options, other than bariatric surgery (Fernandes et al., 2007). The 1980 s generation of air balloons reported many complications and placement problems that led to a new generation of fluid filled balloons (Imaz et al., 2008) namely the BioEnterics Intra- gastric Balloon (BIB®), introduced in 1991. Since then, Bioenterics fluid-filled balloons (BIB), a spherical elastic balloon of silicone filled with between 400 and 700 ml of saline solution has been used (Imaz et al. 2008). It works to induce satiety by reducing the stomach capacity, thereby reducing food intake and encouraging weight loss amongst obese populations. Patients undergoing insertion of an IGB a o su e a o al diet Fe a des et al., 2007). IGB insertion and removal are performed under conscious sedation or general

et al., 2015).

Adverse side effects can be associated with the procedure with patients needing clinical supervision throughout. Oesophageal injury and vomiting are possible due to balloon slippage. Absolute contraindications for the procedure involve a hiatus hernia and abnormalities of the pharynx or oesophagus (Fernandes et al., 2007). Significant nausea, vomiting and discomfort were typically experienced in the early insertion period (Brooks et al. 2007).

4.1.2 Effectiveness of an intra-gastric balloon to promote weight loss in adults

Previous reviews of surgical treatment options for obese adults (Colquitt et al. 2003) did not include the use of an intra-gastric balloon due to study quality and criterion set, resulting in a separate review of its use by Fernandes et al. (2007). The review highlighted that due to heterogeneous and partially incomplete data, no conclusion could be made in relation to effectiveness of an IGB compared with conventional treatment. A systematic review in obese adults by Dumonceau (2008), (4877 patients, 30 studies, 18 prospective) found the mean weight loss was 17.8 kg, ranging from 4.9 kg to 28.5 kg, in specific studies with change in BMI of 4.0 - 9.0 kg/m2_{. A separate} meta-analysis by Imaz et al. (2008) (pooled data - 15 studies, 3600 patients) suggested that at 6 months average weight loss was 14.7 kg, representing a loss of 32.1% of excess weight and a change in BMI of 5.7. Consistently, high incidences of nausea and vomiting were experienced in early days of balloon placement (Sallet et al. 2004) yet severe complications were minimal (Dumonceau 2008). Looking at weight loss maintenance, Chuttani et al. (2015) found an average weight loss at 6 and 12 months after Orbera balloon removal was 113.1 kg (average loss of 15.9 kg) and 96.8 kg (average loss of 8.7 kg), respectively. This data indicates that, on average, 52% of the weight lost during Orbera balloon therapy was sustained 12 months after Orbera balloon removal. Generally the balloon was safe, albeit management of initial side effects, with the IGB effective in promoting short term weight loss (Dumonceau 2008).

4.1.3 Rationale for use of intra-gastric balloon treatment in severely obese adolescents

Adolescents have been included in some studies assessing the use of an IGB (Vandenplas et al., 1999; Sallet et al., 2004), yet their outcomes are rarely separated from other patients (Dumoncea 2008). It is because of this lack of focus on adolescents and the dates with which the interventions occurred, that these studies were not included in the scoping review in Chapter 2. A study by Vandenplas et al., (1999) demonstrated a transient beneficial effect with a positive reduction in BMI at 3 month yet this was only identified in five adolescents and was not maintained. In Sallet et al. (2004) study 483 adolescents received an intra-gastric balloon, with 250 patients at 6 month follow-up showing a global weight reduction from baseline BMI of 38.2 kg/m2 _± 9.4 to 6-month BMI of 32.9 kg/m2 _{± 8.3, with a significant reductions in weight status,} 15.2 ± 10.5 kg (Sallet et al., 2004). Sallet et al. (2004) concluded, in contrast to Vandenplas et al. (1999), that obese adolescents who had failed clinical treatment could be a promising target group for the intra-gastric balloon, because the shorter duration of obesity allowing them the greater possibility for change (Sallet et al., 2004). Neither study reported the inclusion of a multidisciplinary lifestyle programme. 4.1.4 Current UK management of severely obese adolescents

Bariatric surgery for severe obesity in adolescents is undoubtedly efficacious but its use remains controversial (Wright and Wales, 2016). NICE makes provision within its guidance for consideration of obesity surgery in adolescents in exceptional circumstances. NHS England is currently examining the commissioning of tier 4 bariatric services for adolescents (Wright and Wales, 2016) but while there are no formally commissioned services, several UK centres offer surgery in exceptional circumstances. Intra-gastric balloons are not routinely used due to a lack of evidence in the severely obese adolescent population.

exhausted all clinical treatment options. The inclusion of a multidisciplinary lifestyle programme, alongside a temporary aid like an IGB, that focuses on behavioural change (drawing from the learning in Chapter 2) is needed as current studies looking at the use of IGB in adolescents and adults has not consistently reported this (Dumonceau et al., 2008). In light of the scarcity of data in severely obese adolescents, pilot studies that explore the feasibility and safety of using an IGB alongside a multidisciplinary lifestyle programme with severely obese adolescents are warranted.