Browsing by Author "Koch, Timothy R."

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    Anastomotic Stricture Formation after Roux-En-Y Gastric Bypass Surgery: A Single Center Retrospective Cohort Study
    Vanga, Rohini R.; Majithia, Raj; Finelli, Frederick C.; Shope, Timothy R.; Koch, Timothy R. (ACT Publishing, 2013-12-21)
    AIM: Roux-en-Y gastric bypass is used for treating medically-complicated obesity. Gastrojejunal anastomotic stricture is a common complication reported in 3% to 27% of these patients. The pathogenesis of postoperative strictures is not well understood, but ischemia has been hypothesized as a major cause. The aim of this study was to evaluate potential factors that could increase the risk of a post-operative anastomotic stricture. METHODS: The records of 165 patients who had gastric bypass from June 2006 to March 2011 were reviewed. Demographics, co-morbidities, smoking status, surgical approach, medication use, and H. pylori status were noted, as well as a diagnosis of gastrojejunal stricture and/or marginal ulceration. RESULTS: Thirty-four symptomatic patients (21%) developed gastrojejunal stricture, while 26 patients (16%) developed marginal ulceration. The majority were women (89%) with a mean age of 43 years and mean body mass index of 51 kg/m2. Caucasians were at a higher risk for developing a stricture. Proton pump inhibitor use and marginal ulceration were significantly associated with risk of stricture, and there was a strong trend in patients with obstructive sleep apnea. Post-operative strictures were successfully treated with an average of two dilation sessions using an endoscopic through-the-scope balloon dilator. CONCLUSION: After gastric bypass, proton pump inhibitor use and marginal ulceration were associated with anastomotic stricture formation. Strictures were more common in Caucasians. A trend towards an increased risk of strictures in patients with sleep apnea was observed, supporting the role of ischemia. Endoscopic balloon dilation relieved symptoms in all patients.
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    Current and future impact of clinical gastrointestinal research on patient care in diabetes mellitus
    Koch, Timothy R.; Shope, Timothy R.; Camilleri, Michael (Baishideng, 2018-11-15)
    The worldwide rise in the prevalence of obesity supports the need for an increased interaction between ongoing clinical research in the allied fields of gastrointestinal medicine/surgery and diabetes mellitus. There have been a number of clinically-relevant advances in diabetes, obesity, and metabolic syndrome emanating from gastroenterological research. Gastric emptying is a significant factor in the development of upper gastrointestinal symptoms. However, it is not the only mechanism whereby such symptoms occur in patients with diabetes. Disorders of intrinsic pacing are involved in the control of stomach motility in patients with gastroparesis; on the other hand, there is limited impact of glycemic control on gastric emptying in patients with established diabetic gastroparesis. Upper gastrointestinal functions related to emptying and satiations are significantly associated with weight gain in obesity. Medications used in the treatment of diabetes or metabolic syndrome, particularly those related to pancreatic hormones and incretins affect upper gastrointestinal tract function and reduce hyperglycemia and facilitate weight loss. The degree of gastric emptying delay is significantly correlated with the weight loss in response to liraglutide, a glucagon-like peptide-1 analog. Network meta-analysis shows that liraglutide is one of the two most efficacious medical treatments of obesity, the other being the combination treatment phentermine-topiramate. Interventional therapies for the joint management of obesity and diabetes mellitus include newer endoscopic procedures, which require long-term follow-up and bariatric surgical procedure for which long-term follow up shows advantages for individuals with diabetes. Newer bariatric procedures are presently undergoing clinical evaluation. On the horizon, combination therapies, in part directed at gastrointestinal functions, appear promising for these indications. Ongoing and future gastroenterological research when translated to care of individuals with diabetes mellitus should provide additional options to improve their clinical outcomes.
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    Obesity Subtypes and Short Term Weight Loss After Vertical Sleeve Gastrectomy: A Retrospective Cohort Study
    Shah, Raj A.; Nath, Anand; Shope, Timothy R.; Pardo Lameda, Ivanesa L.; Brebbia, John S.; Koch, Timothy R. (2022-12)
    AIM: Vertical sleeve gastrectomy has become the most common surgical intervention for medically-complicated obesity. This study examines the hypothesis that a clinical subtype of obesity (psychosocial factors, genetic risk, or early life endocrine disruptors termed obesogens) can identify the best candidates for vertical sleeve gastrectomy. MATERIALS AND METHODS: This is a retrospective cohort study of 225 consecutive new individuals with medically-complicated obesity seen preoperatively in outpatient bariatric clinic in an urban community teaching hospital. Eighty-four individuals underwent sleeve gastrectomy with a minimum of 6 months of follow up. RESULTS: Among 3 subtypes, early life obesogen exposure has been identified in 14.5% of individuals, genetic risk in 24.5% of individuals, and psychosocial factors in 61% of individuals. Percent excess weight loss (mean+/-SD) at 6 months is different among the three groups (pANOVA = 0.024). Individuals with genetic risk (38%+/-14) have significantly less weight loss (p = 0.029) than individuals with psychosocial factors (47%+/-15), while there is no difference compared to the obesogen subtype (41%+/-8.9). CONCLUSION: The most common clinical subtype of obesity is psychosocial factors, and there is significantly higher short term weight loss after sleeve gastrectomy in individuals with psychosocial factors. Weight loss may be limited by an individual’s genetic risk and early life obesogen exposure. A prospective study is required to confirm these findings.
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    Organization of future training in bariatric gastroenterology
    Koch, Timothy R.; Shope, Timothy R.; Gostout, Christopher J. (Baishideng, 2017-09-21)
    A world-wide rise in the prevalence of obesity continues. This rise increases the occurrence of, risks of, and costs of treating obesity-related medical conditions. Diet and activity programs are largely inadequate for the long-term treatment of medically-complicated obesity. Physicians who deliver gastrointestinal care after completing traditional training programs, including gastroenterologists and general surgeons, are not uniformly trained in or familiar with available bariatric care. It is certain that gastrointestinal physicians will incorporate new endoscopic methods into their practice for the treatment of individuals with medically-complicated obesity, although the longterm impact of these endoscopic techniques remains under investigation. It is presently unclear whether gastrointestinal physicians will be able to provide or coordinate important allied services in bariatric surgery, endocrinology, nutrition, psychological evaluation and support, and social work. Obtaining longitudinal results examining the effectiveness of this ad hoc approach will likely be difficult, based on prior experience with other endoscopic measures, such as the adenoma detection rates from screening colonoscopy. As a longterm approach, development of a specific curriculum incorporating one year of subspecialty training in bariatrics to the present training of gastrointestinal fellows needs to be reconsidered. This approach should be facilitated by gastrointestinal trainees' prior residency training in subspecialties that provide care for individuals with medical complications of obesity, including endocrinology, cardiology, nephrology, and neurology. Such training could incorporate additional rotations with collaborating providers in bariatric surgery, nutrition, and psychiatry. Since such training would be provided in accredited programs, longitudinal studies could be developed to examine the potential impact on accepted measures of care, such as complication rates, outcomes, and costs, in individuals with medically-complicated obesity.
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    Prevalence of Biochemical Thiamine Deficiency in a Non-large Urban Population of Individuals with Obesity: A Retrospective Study
    Koch, Timothy R.; Cronin, David C.; Iranmanesh, Ali (Sryahwa Publications, 2024-07)
    Background: Previous studies of individuals with obesity in large urban populations identified biochemical or clinical thiamine deficiency in 15.5% to 29% of individuals. The prevalence of biochemical thiamine deficiency in a non-large urban, obese population is not well defined. Methods: Consecutive patients with obesity (n=400) had been seen in gastroenterology clinic. Individuals (n=23) are excluded from this study because of specific diagnoses. Whole blood thiamine was completed in 130 individuals who had complaints of dysphagia, nausea & vomiting, constipation, abdominal distension, or symptoms of peripheral neuropathy. Results: Men comprised 84% of the 130 subjects with 83% identified as white men and 17% as black men. There were 64 individuals (49%) with type 2 diabetes. Four individuals (3%) have biochemical thiamine deficiency of whom two (50%) have type 2 diabetes. Two thiamine deficient individuals have dysphagia as a complaint, one has nausea/vomiting, and one has peripheral neuropathy. Conclusions: Despite the high percentage of individuals with type 2 diabetes and enrollment of patients with symptoms consistent with thiamine deficiency, there was a low prevalence of biochemical thiamine deficiency in individuals with obesity in this non-large urban population. Potential explanations for this result may include dietary thiamine intake differences, a higher rate of thiamine supplementation, or lower body mass index. A whole blood thiamine level is unlikely to be useful when screening for thiamine deficiency, but supplemental thiamine may be helpful in determining whether a patient with a suggestive gastrointestinal symptom has thiamine deficiency.
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    Prevalence of irritable bowel syndrome in morbidly obese individuals seek­ing bariatric surgery
    Andalib, Iman; Hsueh, William; Shope, Timothy R.; Brebbia, John S.; Koch, Timothy R. (ACT Publishing, 2018-01-01)
    AIM: An increased prevalence of irritable bowel syndrome has been reported in obese individuals. Factors important in weight loss after bariatric surgery are incompletely understood, and small intestinal bacterial overgrowth in individuals with type 2 diabetes mellitus is a potential risk factor. Our aims are to examine whether the increased prevalence of irritable bowel syndrome in obese individuals seeking bariatric surgery is associated with diabetes mellitus and whether weight loss after bariatric surgery is altered by irritable bowel syndrome. METHODS: This is a single-center, retrospective study performed in a large, urban community teaching hospital. Individuals seen in gastrointestinal bariatric clinic prior to bariatric surgery from 2010 to 2013 completed a Manning symptom criteria questionnaire prior to their medical evaluation; ≥3 Manning criteria is accepted as diagnostic of irritable bowel syndrome. Percent excess weight loss at 6-, 12-, and 24-months after bariatric surgery is recorded. RESULTS: Thirty percent of 278 individuals seeking bariatric surgery have ≥3 Manning criteria. There is no relationship between type 2 diabetes mellitus and the presence of ≥3 Manning criteria (p>.05), nor is body mass index a significant risk factor for irritable bowel syndrome (p>.05). At 6-, 12-, and 24-months after Roux-en-Y gastric bypass or vertical sleeve gastrectomy, there is no difference in percent excess weight loss in individuals with ≥3 Manning criteria compared to individuals with ≥2 Manning criteria (for both surgical procedures: p>.05). CONCLUSION: A diagnosis of diabetes mellitus or body mass index do not explain the high prevalence of irritable bowel syndrome identified in individuals with obesity seeking bariatric surgery, and irritable bowel syndrome does not alter weight loss after bariatric surgery.
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    Prolonged Hypercupremia after Laparoscopic Vertical Sleeve Gastrectomy Successfully Treated with Oral Zinc
    Koch, Timothy R.; Zubowicz, Elizabeth A.; Gross, John B., Jr. (Hindawi, 2019-06-04)
    A 30-year-old female underwent vertical sleeve gastrectomy. Postoperatively, hypercupremia and elevated ceruloplasmin were identified. Further testing revealed normal blood levels of transaminases, alkaline phosphatase, and albumin. She stopped ingestion of multivitamins, began a copper-free multivitamin, and then began a low copper diet, but with no improvement in hypercupremia. Protein electrophoresis was normal with no M-spike. Urinary copper excretion was normal at 0.24 micromol/24 hours (normal: < 0.55), and there were no Kayser-Fleischer rings on slit lamp examination. Two years postoperatively, she lost 44% of excess preoperative weight and she began zinc sulfate before meals twice daily (115 mg elemental Zinc/day). At 2 months and 8 months later, plasma copper and ceruloplasmin had essentially normalized. Increased production of ceruloplasmin could have been a response to significant weight loss or the presence of nonalcoholic steatohepatitis. The mechanism of zinc’s beneficial effect is uncertain but may be related to suppressing hepatic synthesis of or secretion of ceruloplasmin.
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    Structural studies of precursor and partially oxidized conducting complexes. II. A neutron diffraction study of disodium dibromotetracyanoplatinate dihydrate
    Maffly, Robert L.; Johnson, Paul L.; Koch, Timothy R.; Williams, Jack M. (International Union of Crystallography, 1977-02-01)
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    Structural studies of precursor and partially oxidized conducting complexes. VI. A neutron diffraction study of dicesium tetracyanoplatinate(II) monohydrate
    Johnson, Paul L.; Koch, Timothy R.; Williams, Jack M. (International Union of Crystallography, 1977-04-15)
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    Structural studies of precursor and partially oxidized conducting complexes. VII. A neutron diffraction study of disodium tetracyanoplatinate(II) trihydrate
    Johnson, Paul L.; Koch, Timothy R.; Williams, Jack M. (International Union of Crystallography, 1977-06-01)
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    Structural studies of precursor and partially oxidized conducting complexes. XI. A neutron diffraction study of barium dibromotetracyanoplatinate(IV) hydrate
    Koch, Timothy R.; Johnson, Paul L.; Washecheck, Donald M.; Cornish, Thomas L.; Williams, Jack M. (International Union of Crystallography, 1977-10-01)
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    Will gastroenterologists be successful as metabolic physicians?
    Sharbaugh, Matthew E.; Shope, Timothy R.; Koch, Timothy R. (ACT Publishing, 2020-04-01)
    As the result of incomplete treatments, obesity continues to be a worldwide origin for multiple medical problems, including metabolic disorders. With the worldwise rise in obesity, the prevalence of type 2 diabetes mellitus has increased in both men and women. Effective treatments for obesity can improve the treatment of metabolic disorders. The adjustable gastric band and the vertical sleeve gastrectomy are less complex gastric surgeries utilized by bariatric surgeons for the treatment of metabolic disorders. Studies have supported the utility of both of these gastric surgeries for the treatment of subgroups of individuals with diabetes mellitus. The field of gastroenterology has mainly been examining four major endoscopic procedures for the treatment of obesity: intragastric balloons, intragastric aspiration systems, intraluminal gastric suturing, and intraluminal barriers deployed within the upper small intestine. Ongoing studies are examining the ability of these endoscopic procedures to treat metabolic disorders, which includes reduction in the blood levels of hemoglobin A1C in individuals with diabetes mellitus. Ongoing issues are discussed that should be addressed prior to the wide spread utilization of endoscopic procedures for the treatment of this metabolic disorder.
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    X-ray diffuse scattering of one-dimensional tetracyanoplatinate salts
    Schultz, A. J.; Stucky, G. D.; Williams, Jack M.; Koch, Timothy R.; Maffly, R. L. (Elsevier, 1977-01)