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Nelson, Alfred D.

https://orcid.org/0000-0002-6595-2534

Mayo Clinic

AdventHealth Orlando

Citations 20

S0426 Evaluation of Manometric Parameters in Patients With Asthma: A Novel Study Using High-Resolution Esophageal Manometry
Montenegro, Marilia , Werlang, Monia E., Nelson, Alfred D. , Lacy, Brian E.

American Journal of Gastroenterology | October 24, 2020 | Volume: 115 | Issue: 1 | Pages: S212-S213

10.14309/01.ajg.0000703752.10253.1b Get It

A single‐center, prospective, double‐blind, sham‐controlled, randomized study of the effect of a vibrating capsule on colonic transit in patients with chronic constipation
Nelson, Alfred D. , Camilleri, Michael , Boldingh, Amy, Busciglio, Irene, Burton, Duane D. , Ryks, Michael, Zinsmeister, Alan R., Camilleri, M , Acosta, Andrés

Neurogastroenterology & Motility | February 8, 2017 | Volume: 29 | Issue: 7 | Pages: No page available

10.1111/nmo.13034 Get It

AbstractBackgroundIn an open‐label study of 26 patients with IBS‐C and chronic constipation, treatment with a vibrating (VIBRANT) capsule twice a week for 7.5 weeks resulted in 88.5% responders. Effects on colonic transit are unclear. We aimed to compare effects of VIBRANT and sham capsule treatment on colonic transit in patients with functional constipation.MethodsPatients with functional constipation (Rome III criteria) were randomized to VIBRANT or sham capsule treatment for 8 weeks and underwent scintigraphic colonic transit measurements during week 8. We estimated the overall rate of colonic transit from the slope of progression of colonic geometric center over 48 hours. The capsule was activated 8 hours after ingestion, and the vibration sequence included 240 cycles.Key ResultsThere were no significant group differences in overall colonic transit [GC48, 2.76 (IQR 2.42‐4.03) for sham group and 3.46 (2.55‐4.61) for active treatment group (P=.13)]. Additionally, the progression of the isotope through the colon was numerically faster, though not significantly different (slope, P=.14) in the VIBRANT capsule group compared to the sham group. Three participants in the VIBRANT capsule group had accelerated colonic transit at 32 hours and faster colonic transit slope compared to the 95th percentile of the sham group.Conclusions and InferencesAlthough there were no group differences between VIBRANT and sham capsule treatment on colonic transit, at least one (and possibly three) of 12 patients receiving the VIBRANT capsule had faster colonic transit. The vibration parameters to accelerate colonic transit in patients with functional constipation require further optimization.
Opioid analgesic use among patients presenting with acute abdominal pain and factors associated with surgical diagnoses
Khemani, Disha, Camilleri, Michael , Roldan, Ana , Nelson, Alfred D. , Zinsmeister, Alan R., Park, Seon‐Young , Acosta, Andrés

Neurogastroenterology & Motility | December 26, 2016 | Volume: 29 | Issue: 5 | Pages: No page available

10.1111/nmo.13000 Get It

AbstractBackgroundThe prevalence of chronic opioid use among non‐cancer patients presenting with acute abdominal pain (AAP) is unknown. The aim was to characterize opioid use, constipation, diagnoses, and risk factors for surgical diagnoses among non‐cancer patients presenting with AAP to an emergency department (ED).MethodsWe performed a retrospective, observational cohort study of all (n=16,121) adult patients (88% from MN, IA and WI) presenting during 2014 with AAP. We used electronic medical records, and focused on 2352 adults with AAP who underwent abdominal CT scan within 24 hours of presentation. We determined odds ratios of association with constipation and features predicting conditions that may require surgery (surgical diagnosis).Key ResultsThere were 2352 eligible patients; 18.8% were opioid users. Constipation was more frequent in opioid (35.1%) compared to non‐opioid users [OR 2.88 (95% CI 2.28, 3.62)]. Prevalence of surgical diagnosis in the opioid and non‐opioid users was 35.3% and 41.7% respectively (P=.019). By univariate analysis, age and neutrophil count independently predicted increased risk, and chronic opioid use decreased risk of surgical diagnosis. Internal validation of logistic models using a randomly selected validation subset (25% of entire cohort, 587/2352) showed receiver operating characteristic (ROC) curves for the validation and full cohorts were similar.Conclusions and InferencesApproximately 19% of adults presenting with AAP were opioid users; constipation is almost three times as likely in opioid users compared to non‐opioid users presenting with AAP. Factors significantly associated with altered risk of surgical diagnoses were age, opioid use, and neutrophil count.
Comparison of efficacy of pharmacological treatments for chronic idiopathic constipation: a systematic review and network meta-analysis
Nelson, Alfred D. , Camilleri, Michael , Chirapongsathorn, Sakkarin , Vijayvargiya, Priya , Valentin, Nelson, Shin, Andrea , Erwin, Patricia J., Murad, M. Hassan , Wang, Zhen , Murad, M Hassan

Gut | June 11, 2016 | Volume: 66 | Issue: 9 | Pages: 1611-1622

10.1136/gutjnl-2016-311835 Get It

Objective To compare efficacy of pharmacotherapies for chronic idiopathic constipation (CIC) based on comparisons to placebo using Bayesian network meta-analysis. Data sources We conducted searches (inception to May 2015) of MEDLINE, EMBASE, Scopus and Cochrane Central, as well as original data from authors or drug companies for the medications used for CIC. Study selection Phase IIB and phase III randomised, placebo-controlled trials (RCT) of ≥4 weeks' treatment for CIC in adults with Rome II or III criteria for functional constipation; trials included at least one of four end points. Data extraction and synthesis Two investigators independently evaluated all full-text articles that met inclusion criteria and extracted data for primary and secondary end points, risk of bias and quality of evidence. Outcomes Primary end points were ≥3 complete spontaneous bowel movements (CSBM)/week and increase over baseline by ≥1 CSBM/week. Secondary end points were change from baseline (Δ b ) in the number of SBM/week and Δ b CSBM/week. Results Twenty-one RCTs (9189 patients) met inclusion and end point criteria: 9 prucalopride, 3 lubiprostone, 3 linaclotide, 2 tegaserod, 1 each velusetrag, elobixibat, bisacodyl and sodium picosulphate (NaP). All prespecified end points were unavailable in four polyethylene glycol studies. Bisacodyl, NaP, prucalopride and velusetrag were superior to placebo for the ≥3 CSBM/week end point. No drug was superior at improving the primary end points on network meta-analysis. Bisacodyl appeared superior to the other drugs for the secondary end point, Δ b in number of SBM/week. Conclusions Current drugs for CIC show similar efficacy. Bisacodyl may be superior to prescription medications for Δ b in the number of SBM/week in CIC.
Effects of ghrelin receptor agonist, relamorelin, on gastric motor functions and satiation in healthy volunteers
Nelson, Alfred D. , Camilleri, Michael , Busciglio, Irene, Nord, Sara Linker, Boldingh, Amy, Rhoten, Deborah, Ryks, Michael, Burton, Duane D. , Acosta, Andrés

Neurogastroenterology & Motility | June 10, 2016 | Volume: 28 | Issue: 11 | Pages: 1705-1713

10.1111/nmo.12870 Get It

AbstractBackgroundSynthetic human ghrelin accelerates gastric emptying, reduces gastric accommodation, and results in numerical increases in postprandial symptom scores. The ghrelin receptor agonist, relamorelin, accelerates gastric emptying in patients with diabetic gastroparesis.AimTo measure pharmacological effects of relamorelin on gastric accommodation, distal antral motility, and satiation in healthy volunteers.MethodsIn a placebo‐controlled, double‐blind, randomized study of 16 healthy volunteers, we compared effects of 30 μg subcutaneous (s.c.) relamorelin to placebo on: (i) gastric volumes measured by single photon emission computed tomography, (ii) 1‐h postprandial distal antral motility index (MI) by 15‐lumen perfusion gastroduodenal manometry, and (iii) satiation tested by Ensure nutrient drink test. Primary endpoints were: fasting and postprandial gastric volumes, distal antral phasic pressure activity (number of contractions, mean amplitude, and MI), and maximum tolerated volume. Results were normally distributed and the two treatment groups were compared using t‐test.Key ResultsRelamorelin, 30 μg s.c., significantly increased the number of contractions in the distal antrum during 0–60 min postmeal when compared to placebo (p = 0.022); this was also observed in the first two 15‐min periods (p = 0.005 and 0.015 for number of contractions 0–15 and 16–30). There was borderline increase in MI0‐15 (p = 0.055) and numerically increased MI0‐60 (p = 0.139) and MI16‐30 (p = 0.116). The amplitude of contractions was not significantly increased. Relamorelin did not significantly alter fasting or postprandial gastric volumes, gastric accommodation, or satiation volumes and symptoms.Conclusions & InferencesRelamorelin increases frequency of distal antral motility contractions without significant effects on amplitude of contractions. The lack of inhibition of accommodation and absence of increase in satiation symptoms support relamorelin for the treatment of symptomatic gastroparesis (ClinicalTrials.gov NCT02466711).
Opioid-induced constipation: advances and clinical guidance
Nelson, Alfred D. , Camilleri, Michael

Therapeutic Advances in Chronic Disease | January 25, 2016 | Volume: 7 | Issue: 2 | Pages: 121-134

10.1177/2040622315627801 Get It

Currently opioids are the most frequently used medications for chronic noncancer pain. Opioid-induced constipation is the most common adverse effect associated with prolonged use of opioids, having a major impact on quality of life. There is an increasing need to treat opioid-induced constipation. With the recent approval of medications for the treatment of opioid-induced constipation, there are several therapeutic approaches. This review addresses the clinical presentation and diagnosis of opioid-induced constipation, barriers to its diagnosis, effects of opioids in the gastrointestinal tract, differential tolerance to opiates in different gastrointestinal organs, medications approved and in development for the treatment of opioid-induced constipation, and a proposed clinical management algorithm for treating opioid-induced constipation in patients with noncancer pain.
Characteristics of chronic megacolon among patients diagnosed with multiple endocrine neoplasia type 2B
Gibbons, Denys , Camilleri, Michael , Nelson, Alfred D. , Eckert, Deborah J., Eckert, Deborah

United European Gastroenterology Journal | October 13, 2015 | Volume: 4 | Issue: 3 | Pages: 449-454

10.1177/2050640615611630 Get It

Ehlers Danlos syndrome and gastrointestinal manifestations: a 20‐year experience at Mayo Clinic
Nelson, Alfred D. , Mouchli, Mohamad, Valentin, Nelson, Deyle, David R. , Pichurin, Pavel N. , Camilleri, Michael , Acosta, Andrés

Neurogastroenterology & Motility | September 17, 2015 | Volume: 27 | Issue: 11 | Pages: 1657-1666

10.1111/nmo.12665 Get It

Abstract Background Gastrointestinal ( GI ) manifestations are found in Ehlers Danlos syndrome ( EDS ) hypermobility subtype ( HM ). We aimed to assess associations between EDS HM and other EDS subtypes with GI manifestations. Methods We reviewed medical records of EDS patients evaluated at Mayo Clinic's Medical Genetics Clinic 1994–2013. We extracted information regarding EDS subtypes, GI manifestations, and treatments. Key Results We identified 687 patients; 378 (56%) had associated GI manifestations (female 86.8%, diagnosis mean age 29.6 years). Of the patients identified, 58.9% (43/73) had EDS classic, 57.5% (271/471) EDS HM , 47.3% (27/57) EDS vascular subtypes. In addition, 86 patients had EDS that could not be classified in any of those three subtypes. Commonest GI symptoms were: abdominal pain (56.1%), nausea (42.3%), constipation (38.6%), heartburn (37.6%), and irritable bowel syndrome‐like symptoms (27.5%). Many GI symptoms were commoner in EDS HM than the other subtypes together. Among 37.8% of the 378 patients who underwent esophagogastroduodenoscopy, the commonest abnormalities were gastritis, hiatal hernia and reflux esophagitis. Abnormal gastric emptying was observed in 22.3% (17/76): 11.8% delayed and 10.5% accelerated. Colonic transit was abnormal in 28.3% (13/46): 19.6% delayed and 8.7% accelerated. Rectal evacuation disorder was confirmed in 18/30 patients who underwent anorectal manometry. Angiography showed aneurysms in abdominal vessels in EDS vascular type. Proton pump inhibitors (38%) and drugs for constipation (23%) were the most commonly used medications. A minority underwent colectomy (2.9%) or small bowel surgery (4%). Conclusions & Inferences EDS HM and other subtypes should be considered in patients with chronic functional GI symptoms and abdominal vascular lesions.
Biomarkers for bile acid diarrhoea in functional bowel disorder with diarrhoea: a systematic review and meta-analysis
Valentin, Nelson, Camilleri, Michael , Altayar, Osama , Vijayvargiya, Priya , Nelson, Alfred D. , Murad, M. Hassan , Acosta, Andrés , Murad, M Hassan , Altayar, Osama

Gut | September 7, 2015 | Volume: 65 | Issue: 12 | Pages: 1951-1959

10.1136/gutjnl-2015-309889 Get It

There is no universally available laboratory test to diagnose bile acid diarrhoea (BAD). Objective To conduct a systematic review and meta-analysis to identify a biomarker for idiopathic BAD in patients with functional bowel disorder (FBD) with diarrhoea. Design We searched multiple databases through 15 May 2015. Data were only available to estimate the diagnostic yield of each test (the prevalence of a positive test). Estimates were pooled across studies using the random effects model. Results We included 36 studies, enrolling 5028 patients (24 using 75 selenium homotaurocholic acid test ( 75 SeHCAT) retention of <10%, 6 using fasting serum C4, 3 using fasting serum fibroblast growth factor 19 (FGF19) and 2 based on total faecal bile acid (BA) excretion over 48 h). The diagnostic yields (and 95% CI) of abnormal tests were: 0.308 (0.247 to 0.377) for 75 SeHCAT retention (<10%), 0.171 (0.134 to 0.217) for serum C4, 0.248 (0.147 to 0.385) for serum FGF19 and 0.255 (0.071 to 0.606) for total faecal BA excretion over 48 h. The majority of the analyses were associated with substantial heterogeneity. Performance characteristics relative to a gold standard test could not be estimated. Conclusions Overall, the test with the highest diagnostic yield conducted in the largest number of studies was 75 SeHCAT retention, which is not widely available in many countries outside Europe and Canada. Using different diagnostic tests, 25% (average) of patients with lower FBD with diarrhoea has evidence of idiopathic BAD. These tests serve to identify idiopathic BAD among patients with FBD with diarrhoea. Further studies are required to appraise the performance characteristics of tests for idiopathic BAD.
Chronic opioid induced constipation in patients with nonmalignant pain: challenges and opportunities
Nelson, Alfred D. , Camilleri, Michael

Therapeutic Advances in Gastroenterology | April 20, 2015 | Volume: 8 | Issue: 4 | Pages: 206-220

10.1177/1756283x15578608 Get It

With the recent introduction and approval of medications directed at the treatment of opioid induced constipation (OIC) in patients with nonmalignant pain, there is increased interest and understanding of the unmet need and opportunities to enhance patient management. The high incidence of OIC is associated with rapid increase of narcotic analgesic prescriptions for nonmalignant chronic pain. This review addresses briefly the mechanisms of action of opioids that lead to OIC, the differential tolerance of gastrointestinal organs to the effects of opioids, the size and scope of the problem, the definition and outcome measures for OIC, current differential diagnosis and management algorithms, and the pharmacology and efficacy of treatments for OIC in patients with nonmalignant pain.