An interventional study of LEFT smartwatch app in Gastroesophageal Reflux and Heartburn, sponsored by Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA). Completed at 1 site in Netherlands. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-05-31.
Sponsored by Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA) · Not applicable, Interventional, and Treatment
The main objectives of the study are (1) to investigate if sleep positional therapy, using the LEFT smartwatch app reduces nocturnal gastroesophageal reflux symptoms in patients with gastroesophageal reflux disease symptomatology at night and (2) stimulates patients to avoid sleeping in the right lateral sleep position.
Gastroesophageal reflux disease (GERD) is one of the most common gastro-intestinal disorders and approximately 50-80% of the GERD patients experience nocturnal gastroesophageal reflux symptoms. Symptoms at night have a negative impact on sleep quality, daytime functioning and quality of life. When sleeping in left lateral decubitus position, the stomach is positioned below the esophagus, resulting in less reflux compared to sleeping in right lateral decubitus position. Sleep positional therapy, using an electronic wearable device which gently vibrates in an annoying way when turning in the sleep to the disadvantageous right lateral decubitus position, stimulates subjects to avoid sleeping in the right lateral decubitus position and effectively alleviates nocturnal gastroesophageal reflux symptoms. This prospective single center interventional pilot study will aim to (1) investigate if sleep positional therapy, using the LEFT smartwatch app reduces nocturnal gastroesophageal reflux symptoms in patients with GERD symptomatology at night and (2) stimulates patients to avoid sleeping in the right lateral sleep position.
1,211 studies on the registry are indexed under Gastroesophageal Reflux; 202 are open to participants now.
This study's enrollment of 18 is below the median of 68 across 796 interventional studies indexed under Gastroesophageal Reflux.
Browse Gastroesophageal Reflux studies →Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA) is the lead sponsor of 532 studies on the registry; 183 are open to participants now.
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Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Device: LEFT smartwatch app
The LEFT smartwatch app is an app on the Apple Watch which measures body sleep position and gently vibrates when the body is in the right lateral decubitus position. In this way, patients with nocturnal gastroesophageal reflux symptoms learn to avoid the right lateral sleep position as they will avoid the annoying vibrations. Measurements while using the smartwatch app will be compared to measurements at baseline.
Nocturnal Gastroesophageal Reflux Disease Symptom Severity and Impact Questionnaire (N-GSSIQ)
The primary efficacy measure is relative change in total nocturnal gastroesophageal reflux symptoms measured by the Nocturnal Gastroesophageal Reflux Disease Symptom Severity and Impact Questionnaire (N-GSSIQ). The N-GSSIQ is a 20-item questionnaire measuring the severity, morning impact and concern about nocturnal gastro-esophageal reflux disease. The N-GSSIQ is a validated questionnaire to assess nocturnal GERD symptom severity over the past 2 weeks. The N-GSSIQ is comprised of three subscales: Nocturnal Gastroesophageal Reflux Disease Symptom Severity (13 questions, score range 0-65), Morning Impact of Nocturnal Gastroesophageal Reflux Disease (2 questions, score range 0-10), and Concern about Nocturnal Gastroesophageal Reflux Disease (5 questions, score range 0-20). Total score ranging from 0 to 95. A higher score indicates more severe symptoms.
Time frame: 2 weeks
Treatment success
Percent responders as treatment success, defined as subjects with a minimal 50% reduction in nocturnal gastroesophageal reflux symptoms measured by N-GSSIQ
Time frame: 2 weeks
Change in total Nocturnal Gastroesophageal Reflux Disease Symptom Severity and Impact Questionnaire (N-GSSIQ) score.
Change in total Nocturnal Gastroesophageal Reflux Disease Symptom Severity and Impact Questionnaire (N-GSSIQ) score. The N-GSSIQ is a 20-item questionnaire measuring the severity, morning impact and concern about nocturnal gastro-esophageal reflux disease. The N-GSSIQ is a validated questionnaire to assess nocturnal GERD symptom severity over the past 2 weeks. The N-GSSIQ is comprised of three subscales: Nocturnal Gastroesophageal Reflux Disease Symptom Severity (13 questions, score range 0-65), Morning Impact of Nocturnal Gastroesophageal Reflux Disease (2 questions, score range 0-10), and Concern about Nocturnal Gastroesophageal Reflux Disease (5 questions, score range 0-20). Total score ranging from 0 to 95. A higher score indicates more severe symptoms.
Time frame: 2 weeks
Sleep position
Change in sleep position. Four sleep positions will be studied: left lateral decubitus, right lateral decubitus, supine and prone. The outcome sleep position will be noted as percentage of the time sleeping in a certain sleep position during the entire sleep.
Time frame: 2 weeks
Number of nocturnal reflux free nights
Change in the number of nocturnal reflux free nights measured by daily symptom diary
Time frame: 2 weeks
Reflux disease questionnaire (RDQ)
Change in reflux symptoms measured by Reflux disease questionnaire (RDQ) questionnaire. The RDQ is a validated 12-item questionnaire to obtain information on the current severity and frequency of reflux symptoms (heartburn, regurgitation and dyspepsia). The three subscales are the different reflux symptoms and consist of four questions. Scores were scaled with a Likert scale which ranges from 0 to 5. Subjects have more frequent and severe reflux symptoms if the RDQ score is higher
Time frame: 2 weeks
Pittsburgh Sleep Quality Index (PSQI)
Change in sleep quality measured by Pittsburgh Sleep Quality Index (PSQI). The PSQI is a validated 19-item questionnaire assessing various factors relating to sleep quality, sleep disturbance and usual sleep habits. The 19 items are grouped into seven component scores (sleep quality, sleep onset latency, sleep duration, sleep efficiency, sleep disturbances, use of sleep medication and daytime dysfunction). The seven component scores are summed to calculate a global PSQI score, which has a range of 0-21. A higher score indicates a worse sleep quality; and a score above 5 is suspect for insomnia.
Time frame: 2 weeks
Functional Outcomes of Sleep Questionnaire (FOSQ)
Change in sleep quality measured by Functional Outcomes of Sleep Questionnaire (FOSQ). The FOSQ is a validated questionnaire about sleep-quality of life which consists of 30 questions. The short form which consists of 10 questions will be used in this study. Questions have a 4-point Likert scale. The recall period is not specified, but two weeks will be used in this study. A lowerscore indicates a worse sleep quality.
Time frame: 2 weeks
Ran from Oct 2023 to primary completion in Oct 2024, 12 months.
Of 192 non-industry interventional studies with no phase under Gastroesophageal Reflux, half reached primary completion within 31 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 68. This study's 12 months is below that.
Counting every sponsor, half of 225 studies reached it within 32 months; a quarter within 12 and three quarters within 68.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in May 2025. You cannot join it, but the record below documents what was studied.
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