Gastric emptying time, esophageal pH-impedance parameters, quality of life and gastrointestinal comorbidity in obese children and adolescents.

Objectives and study: Gastroesophageal reflux disease (GERD) and obesity are currently two of the most common disorders in Western populations. Rates of overweight and obesity among children have more than doubled in the past decades, with the most recent estimates indicating that about 30% of children are overweight or obese. Although there are many studies about the association between GERD and obesity in adults, very few data are available for pediatric age. A few years ago, we’ve reported that both total and abdominal obesity are independent risk factors for reflux symptoms in children. The present study was drawn in order to provide further evidence about the relationship between obesity and GERD in children, through the use of instrumental testing such as 13C-octanoic acid breath test (13C-OABT) and multichannel intraluminal impedance pH-testing (MII-pH). Methods: Children and adolescents aged 2-17 years, followed-up at the outpatient clinic for Pediatric Obesity from March 2016 to September 2016, were asked to fullfil 3 different questionnaires, investigating the presence of reflux symptoms, possible associated functional gastrointestinal disorders and both parent- and patient- reported quality of life (QoL). 20 randomly selected obese patients reporting GERD symptoms and 20 obese patients without GERD symptoms were asked to undergo 13C-OABT, in order to evaluate gastric emptying time (GET). Symptomathic patients were also required to undergo MII-pH. Age- and sex- matched asymptomatic non-obese children were enrolled in order to obtain comparative data for non-invasive procedures, such as 13C-OABT and study questionnaires. Results: 113 obese patients (M/F: 60/53; mean age ± SD: 123 ± 7.3 months; range: 48-204 months) were enrolled in the study. Of these, 44/113 (38.9%) reported reflux symptoms. 22/44 underwent MIIpH: the mean reflux index was 14.6% and the mean number of daily reflux episodes was 51.8. 20/44 underwent 13C-OABT: the mean T½ GET was 107.6 min. Among the remaining 69/113 (61.1%) obese asymptomatic patients, 20 underwent 13C-OABT: the mean T½ GET was 116.5 min. 15 healthy non-obese children (M/F: 8/7; mean age ± SD: 115 ± 6.5 months; range: 55-191 months) were enrolled as comparison group. Their mean T½ GET was 100.1 min. Both symptomatic and asymptomatic obese patients had a worse quality of life than non-obese (p:0.003 and p:0.0002, respectively); the percentage of excess body weight was directly related with QoL score (p:0.01); the narrow waist circumference was directly related to GET (p:0.01); chronic functional constipation (FC) and irritable bowel sindrome (IBS) were more prevalent among obese patients with reflux symptoms than obese asymptomatic patients (p:0.03 and p:0.007, respectively). Conclusion: The present study confirms that a high percentage of obese children and adolescents experience gastro-esophageal reflux symptoms. GET was found to be directly related to the narrow waist circumference, though it did not differ significantly between obese and non obese patient groups. Neither subjective nor objective reflux scores were related to GET. Obese patients suffering from reflux symptoms had a higher GI comorbidity than asymptomatic obese patients, reporting more frequently FC and IBS. Finally, as expected, both symptomatic and asymptomatic obese patients had a worse QoL compared to non obese healthy patients.