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Unsedated transnasal endoscopy with ultrathin endoscope as a screening tool for research studies
Robert M Siwiec1, Kulwinder Dua, Sri Naveen Surapaneni
1Medical College of Wisconsin, Division of Gastroenterology and Hepatology, VA Medical Center, Milwaukee, Wisconsin, USA.
Objectives/Hypothesis:
Asymptomatic subjects volunteering for research studies are generally stratified as healthy based on a questionnaire, medical interviewing, and physical examination. The aim of this study was to evaluate the prevalence of upper gastrointestinal (GI) abnormalities in healthy asymptomatic volunteers using unsedated transnasal esophagogastroduodenoscopy (T-EGD) with an ultrathin endoscope as an additional screening tool.
Study Design:
A prospective study from one academic medical center with extensive experience in T-EGD.
Methods:
Consecutive 150 subjects volunteering for research studies were initially screened by using a gastroesophageal reflux disease (GERD) questionnaire, interviewing, and examination. Based on these, they were stratified as healthy asymptomatic volunteers or with GERD. Unsedated T-EGD was then performed by a faculty member who was blinded to the results of the initial assessment.
Results:
On initial assessment using GERD questionnaire, medical interviewing, and physical examination, of the total 150 consecutive research volunteers, 83 (average age 33 ± 16 years; 46 females, 37 males) subjects were healthy asymptomatic volunteers and 67 (average age 36 ± 15 years; 35 females, 32 males) had symptoms of GERD. On T-EGD, GI pathology was found in 15 of 83 (18%) healthy asymptomatic volunteers as compared to 24 of 67 (36%) stratified as having GERD (P < .01). The esophageal abnormalities found in healthy asymptomatic volunteers were esophagitis (13.3%), Barrett's esophagus (2.4%), hiatus hernia (2.4%), and gastritis (2.4%).
Conclusions:
A small but significant number of asymptomatic subjects have abnormal upper GI findings. Hence, transnasal unsedated endoscopy can be considered as a screening tool to stratify subjects as healthy, especially when considering them for research studies.
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