Gastrointestinal problems in diabetes

Constipation prevalence in diabetic patients

Objective the aim of this study was to identify the prevalence of constipation in diabetic patients treated at the endocrinology outpatient clinic at Hospital Universitário Professor Alberto Antunes and PAM Salgadinho, from April to August 2013.

Methods a descriptive and cross-sectional study, carried out through a questionnaire using the Rome III criteria in 372 patients treated at the outpatient endocrinology clinic.

Results of 372 patients evaluated, the frequency of constipation found was 31.2% among diabetic patients. Females predominated in the sample (72.8%) as well as for the frequency of constipation (80.2%). The incidence of type II diabetes was 97.3% and it was observed that 80.2% of the sample was older than 50 years. One hundred and twelve patients with inadequate glycemic control (HgA1c ≥ 7) had an association with constipation.

Conclusion there was an increased frequency of constipation in patients with diabetes mellitus according to the Rome III criteria, in relation to the general population. The inadequate glycemic control in patients with diabetes mellitus increases the frequency of constipation and it is necessary to perform studies that allow the confirmation of this association to demonstrate this hypothesis.

Evaluation of white sweet potato tube-feeding formula in elderly diabetic patients: a randomized controlled trial

BACKGROUND

Elderly people with type 2 diabetes mellitus (T2DM) have an increased risk of diabetes-related microvascular and macrovascular complications, thus diabetic patients with a functioning gastrointestinal tract but without sufficient oral intake require enteral nutrition (EN) formulas to control blood glucose. White sweet potato (WSP) was a kind of sweet potato could provide a healthy carbohydrate source to EN formula. The aim of this study was to examine at risk of malnutrition T2DM patients whether a WSP-EN would attenuate glucose response and elevate nutritional index compared to a standard polymeric formulas.

METHODS

In this randomized, parallel, placebo-controlled, pilot clinical trial to investigate the effects of EN with WSP on aged residents with T2DM in long-term care institutions. In total, 54 eligible participants were randomly assigned to either the non-WSP-EN or WSP-EN group. For 60 days, the WSP-EN group received a WSP formula through nasogastric tube via a stoma with a large-bore syringe. The participants received EN of standard polymeric formulas without WSP in the non-WSP-EN group.

RESULTS

The body weight, body mass index, Mini Nutritional Assessment score, and Geriatric Nutritional Risk Index were significantly higher in the WSP-EN group (p < 0.05). Moreover, the WSP-EN intervention reduced glycated hemoglobin levels (6.73% ± 1.47% vs. 6.40% ± 1.16%), but increased transferrin (223.06 ± 38.85 vs. 245.85 ± 46.08 mg/dL), high-density lipoprotein cholesterol (42.13 ± 10.56 vs. 44.25 ± 8.43 mg/dL), and vitamin A (2.45 ± 0.77 vs 2.74 ± 0.93 μM) levels (p < 0.05). In addition, there was no important side effects including gastrointestinal intolerance with prescribed doses in our WSP-EN treated patients when compared with control ones.

CONCLUSIONS

The results suggest WSP incorporated into enteral formulas can improve nutrition status and glycemic control in elderly diabetic patients.

TRIAL REGISTRATION

NCT02711839, registered 27 May 2015.

Vinegar (acetic acid) intake on glucose metabolism: A narrative review

Vinegar intake is considered a food item that improves blood glucose in humans. This review aimed to discuss studies that investigated the impact of vinegar intake on the glycemic profile in humans and the putative mechanistic cellular pathways in both human and animal models. A search of literature was performed on the Cochrane, MEDLINE and Web of Science databases for articles published between 1995 and 2018. There is considerable support for vinegar having a positive acute effect on blood glucose levels when combined with carbohydrate-rich meals. Conversely, there are few chronic interventions analyzing the impact of vinegar intake on blood glucose. Based on available evidence, we hypothesize three pathways by which vinegar may improve blood glucose: The inhibition of α-amylase action; increased glucose uptake; and mediation by transcription factors. When evaluating the current body of literature, daily vinegar intake in amounts of ∼10-30 mL (∼2-6 tablespoons) appear to improve the glycemic response to carbohydrate-rich meals; however, there is a paucity of studies investigating chronic effects of vinegar intake.

Differential sensitivity of gastric and small intestinal muscles to inducible knockdown of anoctamin 1 and the effects on gastrointestinal motility

KEY POINTS

Electrical pacemaking in gastrointestinal muscles is generated by specialized interstitial cells of Cajal that produce the patterns of contractions required for peristalsis and segmentation in the gut. The calcium-activated chloride conductance anoctamin-1 (Ano1) has been shown to be responsible for the generation of pacemaker activity in GI muscles, but this conclusion is established from studies of juvenile animals in which effects of reduced Ano1 on gastric emptying and motor patterns could not be evaluated. Knocking down Ano1 expression using Cre/LoxP technology caused dramatic changes in in gastric motor activity, with disrupted slow waves, abnormal phasic contractions and delayed gastric emptying; modest changes were noted in the small intestine. Comparison of the effects of Ano1 antagonists on muscles from juvenile and adult small intestinal muscles suggests that conductances in addition to Ano1 may develop with age and contribute to pacemaker activity.

ABSTRACT

Interstitial cells of Cajal (ICC) generate slow waves and transduce neurotransmitter signals in the gastrointestinal (GI) tract, facilitating normal motility patterns. ICC express a Ca2+ -activated Cl- conductance (CaCC), and constitutive knockout of the channel protein anoctamin-1 leads to loss of slow waves in gastric and intestinal muscles. These knockout experiments were performed on juvenile mice. However, additional experiments demonstrated significant differences in the sensitivity of gastric and intestinal muscles to antagonists of anoctamin-1 channels. Furthermore, the significance of anoctamin-1 and the electrical and mechanical behaviours facilitated by this conductance have not been evaluated on the motor behaviours of adult animals. Cre/loxP technology was used to generate cell-specific knockdowns of anoctamin-1 in ICC (KitCreERT2/+ ;Ano1tm2jrr/+ ) in GI muscles. The recombination efficiency of KitCreERT was evaluated with an eGFP reporter, molecular techniques and immunohistochemistry. Electrical and contractile experiments were used to examine the consequences of anoctamin-1 knockdown on pacemaker activity, mechanical responses, gastric motility patterns, gastric emptying and GI transit. Reduced anoctamin-1 caused loss of gastric, but not intestinal slow waves. Irregular spike complexes developed in gastric muscles, leading to uncoordinated antral contractions, delayed gastric emptying and increased total GI transit time. Slow waves in intestinal muscles of juvenile mice were more sensitive to anoctamin-1 antagonists than slow waves in adult muscles. The low susceptibility to anoctamin-1 knockdown and weak efficacy of anoctamin-1 antagonists in inhibiting slow waves in adult small intestinal muscles suggest that a conductance in addition to anoctamin-1 may develop in small intestinal ICC with ageing and contribute to pacemaker activity.

Glucose sensor-augmented continuous subcutaneous insulin infusion in patients with diabetic gastroparesis: An open-label pilot prospective study

Erratic blood glucose levels can be a cause and consequence of delayed gastric emptying in patients with diabetes. It is unknown if better glycemic control increases risks of hypoglycemia or improves hemoglobin A1c levels and gastrointestinal symptoms in diabetic gastroparesis. This study investigated the safety and potential efficacy of continuous subcutaneous insulin infusion (CSII) and continuous glucose monitoring (CGM) in poorly controlled diabetes with gastroparesis. Forty-five type 1 or 2 patients with diabetes and gastroparesis and hemoglobin A1c >8% from the NIDDK Gastroparesis Consortium enrolled in a 24 week open-label pilot prospective study of CSII plus CGM. The primary safety outcome was combined numbers of mild, moderate, and severe hypoglycemic events at screening and 24 weeks treatment. Secondary outcomes included glycemic excursions on CGM, hemoglobin A1c, gastroparesis symptoms, quality-of-life, and liquid meal tolerance. Combined mild, moderate, and severe hypoglycemic events occurred similarly during the screening/run-in (1.9/week) versus treatment (2.2/week) phases with a relative risk of 1.18 (95% CI 0.85–1.64, P = 0.33). CGM time in hypoglycemia (<70 mg/dL) decreased from 3.9% to 1.8% (P<0.0001), time in euglycemia (70–180 mg/dL) increased from 44.0% to 52.0% (P = 0.02), time in severe hyperglycemia (>300 mg/dL) decreased from 14.2% to 7.0% (P = 0.005), and hemoglobin A1c decreased from 9.4±1.4% to 8.3±1.3% (P = 0.001) on CSII plus CGM. Symptom scores decreased from 29.3±7.1 to 21.9±10.2 with lower nausea/vomiting, fullness/early satiety, and bloating/distention scores (P≤0.001). Quality-of-life scores improved from 2.4±1.1 to 3.1±1.1 (P<0.0001) and volumes of liquid nutrient meals tolerated increased from 420±258 to 487±312 mL (P = 0.05) at 24 weeks. In conclusion, CSII plus CGM appeared to be safe with minimal risks of hypoglycemic events and associated improvements in glycemic control, gastroparesis symptoms, quality-of-life, and meal tolerance in patients with poorly controlled diabetes and gastroparesis. This study supports the safety, feasibility, and potential benefits of improving glycemic control in diabetic gastroparesis.

Remodeling of the rat distal colon in diabetes: function and ultrastructure

This study seeks to define and explain remodeling of the distal colon in the streptozotocin (STZ)-treated rat model of diabetes through analysis of resting and active length dependence of force production, chemical composition, and ultrastructure. Compared with untreated controls, the passive stiffness on extension of the diabetic muscle is high, and active force produced at short muscle lengths is amplified but is limited by an internal resistance to shortening. The latter are accounted for by a significant increase in collagen type 1, with no changes in types 3 and 4. In the diabetic colon, ultrastructural studies show unique, conspicuous pockets of collagen among muscle cells, in addition to a thickened basement membrane and an extracellular space filled with collagen fibers and various fibrils. Measurements of DNA and total protein content revealed that the diabetic colon underwent hypertrophy, along with a proportional increase in actin and myosin contents, with no change in the actin-to-myosin ratio. Active force production per cross-sectional area was not different in the diabetic and normal muscles, consistent with the proportionality of changes in contractile proteins. The stiffness and the limit to shortening of the diabetic colon were significantly reduced by treatment with the glycation breaker alagebrium chloride (ALT-711), with no change in collagen contents. Functionally, this study shows that, in diabetes, the production of collagen type 1 and glycation increase stiffness, which limits distensibility on filling and limits shortening and expulsion of contents, both of which can be alleviated by treatment with ALT-711.

Sensitivity of palm print sign in prediction of difficult laryngoscopy in diabetes: A comparison with other airway indices

Background and Aims:

Diabetic patients are prone for the limited joint mobility syndrome. The atlanto-occipital joint involvement limits adequate extension of head and neck during laryngoscopy making intubation difficult. The collagen glycosylation starts in the fourth and fifth inter-phalangeal joints. The degree of inter-phalangeal involvement can be assessed by scoring the ink impression made by the palm of the dominant hand (palm print [PP] sign) The aim of our study was to evaluate the PP sign as a screening tool for predicting difficult laryngoscopy in diabetic patients.

Methods:

A total of 60 diabetic patients undergoing general anaesthesia with endotracheal intubation were assessed pre-operatively for their airway indices using the modified Mallampati test, thyromental distance, degree of head extension, the PP test and the prayer sign and their corresponding Cormack–Lehane scores were noted. Statistical analysis was performed using Fischer exact test.

Results:

Of the 60 patients, 15 had positive PP sign. Of the 13 difficult laryngoscopies encountered, 10 patients had a positive PP sign. PP sign was the most sensitive index in predicting difficult laryngoscopy. P =0.000 was obtained and considered as statistically significant. The sensitivity was 76.9%, specificity 89.4%, positive and negative predictive value 71.4% and 91.3% and accuracy 86.7%, respectively. The other signs were not significant in predicting difficult laryngoscopy.

Conclusion:

The PP test appears to be the most sensitive and specific in the prediction of difficult laryngoscopy in diabetic patients.

Gastrointestinal motility revisited: The wireless motility capsule

INTRODUCTION

The wireless motility capsule (WMC) is a novel ambulatory technology that concurrently measures intraluminal pH, temperature, and pressure as it traverses the gastrointestinal tract.

OBJECTIVES

We aim to provide a concise summary of the WMC, detailing the procedure for its administration and the parameters it records. We also review the evidence that has validated the WMC against other methods currently regarded as 'gold standard'.

CONCLUSIONS

The WMC offers a number of advantages over and above current techniques, especially with respect to patient tolerability, safety, and standardization. The WMC represents a considerable enhancement of the researchers' and clinicians' investigatory armamentarium. If this technology becomes widely adopted, coupled with international consensus upon the interpretation of physiological data derived therein, it may herald a new and exciting era in gastrointestinal physiology.

Assessing constipation in palliative care within a gastroenterology framework

BACKGROUND

Constipation is common and distressing in palliative care. Despite this, approaches to assessment and subsequent treatment are most remarkable for the numbers who fail adequate palliation.

AIM

The primary aim of this paper is to summarise the current approaches to assessing constipation in palliative care, contrasting these approaches with those recommended by gastroenterologists in the assessment of resistant constipation in non-palliative care. The secondary aim is to suggest ways that the approaches used by gastroenterologist could be modified to be tolerable to palliative care.

DESIGN

A non-systematic review of the literature was undertaken.

DATA SOURCES

The electronic databases (MEDLINE, CINHAL) were searched for English language articles that explored assessment of constipation in palliative care and evidence-based gastroenterology guidelines that summarised assessment and management of constipation.

RESULTS

Currently, the assessment of constipation in palliative care is predominantly based on people's reports, physical examination and if further imaging is deemed necessary, a plain abdominal radiograph. However, data in non-palliative care patients refutes the usefulness of self-reported symptoms to localise whether problems are due to colon dysfunction or structures of defaecation. Plain radiographs are most useful to exclude a bowel obstruction only. In cases of resistant constipation, gastroenterology guidelines recommend an assessment approach that includes measuring colon transit time and an assessment of the structures that facilitate defaecation.

CONCLUSIONS

Current approaches to assessing constipation in palliative care are very different to those recommended by gastroenterology guidelines. However, modified approaches may be tolerable to palliative care patients and offer the chance of developing targeted palliation.

The prevalence of bowel problems reported in a palliative care population

CONTEXT

Constipation and other disturbances of bowel function are distressing problems for people with specialist palliative care needs. Recent observations suggest that such problems may worsen as people become more unwell, but the changes in intensity over time are not well documented.

OBJECTIVES

The objectives of this work were to understand the prevalence, intensity, and progression of self-reported bowel disturbances across a community palliative care population, which included people with cancer and noncancer diagnoses.

METHODS

All people referred to a community-based palliative care service over a period of 6.3 years had their bowel problem scores reported, using a numerical rating score at every clinical encounter until their death, at four discrete time points, namely, 90, 60, 30, and seven days before death. This allowed change over three time periods to be considered. At the same time, other symptom scores were collected including nausea, fatigue, pain, appetite problems, and breathing problems. Patients were categorized according to the underlying disease that accounted for their referral to palliative care, namely, cancer diagnoses (upper gastrointestinal cancers, lower gastrointestinal cancers, cancers of the associated digestive organs, and other cancers) and nonmalignant diagnoses. Group differences over the time periods were assessed using analysis of variance. Bivariate analysis was used to explore the relationship between bowel disturbances and other symptoms using Spearman's Rho correlation.

RESULTS

For 7772 patients, data were collected an average of 22.5 times, generating 174,783 data collection points over an average of 98.6 days on the service. At the time of referral to the service, 3248 (42.4%) people had disturbed bowel scores, 548 (7.2%) of whom described these as severe. Only 1020 (13.1%) people never described disturbed bowel function over their time in palliative care. At each time point, approximately one-third were experiencing disturbed bowel function, with proportionally greater numbers of people experiencing more significant problems as death approached (Χ(2) (9)=119.3; P<0.001). Most referrals to the service were because of cancer diagnoses, with no significant differences noted between the bowel disturbance scores of those with cancer diagnoses compared with those with nonmalignant disease. Associations between bowel problem score and appetite problems, nausea, breathing problems, fatigue, and pain were explored. Although weak, there were statistically significant associations between all symptoms and bowel problem scores except for breathing problems.

CONCLUSION

In conclusion, disturbed bowel function consistently remains a problem for people under the care of palliative care services, with the proportion of people with severe problems increasing as death approaches. This is despite the time and number of interventions currently used to palliate these problems.

Diabetic colon preparation comparison study

The purpose of the present study was to establish an optimal colon preparation for persons with diabetes who are undergoing colonoscopies. Specifically, the aim was to compare the difference between an experimental and standard preparation. Adequacy of bowel preparation is critical for good bowel visualization. Compared with nondiabetic patients, persons with diabetes have slower gastric emptying, colonic transit, and colon evacuation. Inadequate preparations may lead to suboptimal colonoscopy resulting in overlooked pathology, repeated examinations with associated risks, and organizational inefficiencies. Using a single-blind experimental design, 198 persons with diabetes who were scheduled to receive colonoscopies were randomly assigned to either the experimental (diabetic colon preparation) or the control (standard colon preparation) group. Patients in the diabetic colon preparation group had 70% good colon preparations compared with 54% in the standard group, and this finding was significant (χ = 5.14, p = 0.02). Results indicate that diabetic patients receiving 10 ounces of magnesium citrate 2 days prior to their colonoscopies followed by 10 ounces of magnesium citrate and 4-L polyethylene glycol the day prior to the procedure had cleaner colons than those receiving standard preparation of 10 ounces of magnesium citrate and 4-L polyethylene glycol the day prior to procedure. This colon preparation is safe, feasible, well-tolerated, and effective.

Orocecal transit time and small intestinal bacterial overgrowth in type 2 diabetes patients from North India

BACKGROUND

Diarrhea, constipation, flatulence, and abdominal pain are common complaints in type 2 diabetes patients. Impaired intestinal motility is often followed by small intestinal bacterial overgrowth (SIBO). Therefore, this study was planned to determine the incidence of SIBO and its relation with orocecal transit time (OCTT) in type 2 diabetes patients.

SUBJECTS AND METHODS

SIBO and OCTT were measured by using noninvasive glucose and lactulose hydrogen breath tests, respectively. For this study, 84 patients with type 2 diabetes mellitus in the age range 30-65 years and 45 age-matched apparently healthy controls were enrolled.

RESULTS

The glucose hydrogen breath test was suggestive of SIBO in 15.5% of patients with type 2 diabetes mellitus but in one (2.2%) of controls. There was a significant increase (P<0.001) in OCTT in type 2 diabetes patients compared with controls. It was also observed that OCTT in type 2 diabetes patients with SIBO was significantly delayed (P<0.001) compared with type 2 diabetes patients without SIBO.

CONCLUSION

This study indicates that SIBO in diabetes patients may be due to delayed OCTT.

Colonic motor dysfunction in human diabetes is associated with enteric neuronal loss and increased oxidative stress

BACKGROUND

Gastrointestinal dysfunction is very common in diabetic patients. We assessed the changes in the colonic enteric nervous system using colectomy specimens and intestinal biopsies from diabetic subjects and age-matched controls.

METHODS

In control and diabetic colons, we determined the total ganglion area (hematoxylin-eosin staining), changes in neuronal markers-protein gene product 9.5, peripherin, neuronal nitric oxide synthase (nNOS), neuropeptide Y (NPY), choline acetyl transferase (ChAT) and vasoactive intestinal peptide (by immunostaining), apoptosis (cleaved caspase-3 staining) and reduced glutathione levels. Superoxide dismutase mRNA was determined in enteric ganglia isolated by laser capture micro dissection. Isometric muscle recording was used to assess contraction and relaxation responses of colonic circular muscle strips. Apoptosis in enteric neurons under hyperglycemia in vitro was determined by cleaved caspase-3 Western blotting and protective effects of lipoic acid were evaluated.

KEY RESULTS

Diabetic subjects had higher incidence of lower gastrointestinal symptoms like constipation and diarrhea at baseline prior to surgery. Diabetic ganglia displayed significant decrease in ganglion size due to enhanced apoptosis and loss of peripherin, nNOS, NPY, and ChAT neurons. Reduced glutathione levels in the diabetic colon (HbA1C > 7%) were significantly less than the control, indicating increased oxidative stress. Colonic circular muscle strips from diabetic subjects showed impaired contraction and relaxation responses compared with the healthy controls. Hyperglycemia-induced cleaved caspase-3 in enteric neurons was reversed by lipoic acid.

CONCLUSIONS & INFERENCES

Our data demonstrate loss of enteric neurons in the colon due to increased oxidative stress and apoptosis which may cause the motility disturbances seen in human diabetes. Antioxidants may be of therapeutic value for preventing motility disorders in diabetes.

Small intestinal bacterial overgrowth in gastroparesis: are there any predictors?

BACKGROUND

There is some degree of overlap in the symptomatic spectrum of patients with gastroparesis and small intestinal bacterial overgrowth (SIBO) and some of the etiologies for gastroparesis, such as diabetes mellitus and vagotomy are known to predispose to SIBO. The aims of our study were to measure the prevalence of SIBO in a cohort of gastroparetic patients with prominence of abdominal pain and bloating and try to identify predictors with regard to demographics, concurrent use of medications such as prokinetics, proton pump inhibitors, and opiate analgesics, and predominant bowel movement abnormality.

METHODS

Glucose breath testing (GBT) for SIBO was performed in 50 patients (41 females) with gastroparesis. Demographic data, medication profiles, baseline and peak measurements of hydrogen or methane gas on the GBT, and results of the most recent gastric emptying scintigraphy test were recorded.

RESULTS

Thirty of fifty (60%) patients had a positive GBT for SIBO on the basis of hydrogen (63%), methane (27%), or both criteria (10%). SIBO was more likely (P=0.001) in patients with gastroparetic symptoms of greater duration (mean 5 y; 95% CI: 4-6 y). No significant differences were noted in both groups with regard to age, sex, or etiology of gastroparesis. Gastric emptying was similar in the SIBO and non-SIBO group (P>0.05). After adjusting for tegaserod and opiate analgesic use, 14/23 (61%) had a positive GBT.

CONCLUSIONS

SIBO is very common in gastroparetics with predominance of abdominal pain and bloating, especially those with a longer duration of gastroparesis. Awareness of SIBO in the setting of gastroparesis will facilitate separation of the 2 entities and allow appropriate therapies to be instituted.

Anal pressure in experimental diabetes

PURPOSE

Diabetes mellitus is a metabolic endocrine disorder that affects many systems, the gastrointestinal system often being among the affected systems. This experimental study work was designed to demonstrate altered anal sphincter pressures in an experimental model of diabetes mellitus (DM).

MATERIALS AND METHODS

Male Wistar rats (mean weight = 250 g) were used and randomized in two groups (n = 10): CO = control and DM. DM was induced by administering a single dose of streptozotocin. Glycemic levels were measured at the start (time = 0) and end (time = 60) of the experiment and anorectal manometry at the end.

RESULTS

DM rats presented a significant increase in glycemia at day 60 (DM = 407.14 +/- 73.76) as compared to the control group (time 0 = 175.7 +/- 18.62 and time 60 = 198.04 +/- 28.66). Anorectal manometry showed a significant decrease in anal pressure in the DM group at day 60 (DM = 34.2 +/- 4.97) as compared to the CO group at the same time (CO = 67.4 +/- 2.06), with P < 0.01 and P < 0.001 (Student's t test).

CONCLUSIONS

The results suggest that DM, due to the high glycemic levels, lead to alterations such as anal sphincter hypotony, which may cause complications such as fecal incontinence.

Faecal incontinence in older people

Faecal incontinence in older people is a distressing and socially isolating symptom and increases the risk of morbidity, mortality and dependency. Many older individuals with faecal incontinence will not volunteer the problem to their general practitioner or nurse and, regrettably, health care providers do not routinely enquire about the symptom. Even when older people are noted by health care professionals to have faecal incontinence, the condition is often managed passively, especially in the long-term care setting where it is most prevalent. The importance of identifying treatable causes of faecal incontinence in older people, rather than just managing passively, is strongly emphasized in national and international guidance, but audit shows that adherence to such guidance is generally poor. This article describes epidemiology, causes, assessment, diagnosis and treatment of faecal incontinence in older people.

Upper gastrointestinal symptoms in type 2 diabetes mellitus and detection of gastric emptying by ultrasongraphy

AIM: To investigate the relationship between upper gastrointestinal (GI) symptoms and gastric emptying in patients with type 2 diabetes mellitus.

METHODS: A total of 411 patients with type 2 diabetes mellitus were examined in Beijing Shunyi District Hospital from November 2005 to October 2007, and 264 normal individuals were used as controls. We statistically analyzed the rate of GI symptoms and the scores of severity. Ultrasound scan was performed to measure the gastric emptying rate 30, 60, 90 min after drinking water.

RESULTS: The rate of GI symtoms in diabetic patients was significantly higher than that in normal controls (60.3% vs 16.7%, P < 0.01). The most common GI symptoms in diabetic patients were epigastric fullness (77.9%) and abdominal distention or belching (61.1%). The scores of symptomic severity were also higher in diabetic patients (P < 0.01). The gastric emptying in patients with diabetes was delayed as compared with that in normal controls 30, 60 and 90 min after drinking water (P < 0.01). Diabetic patients with normal and delayed gastric emptying in 60 min showed significant differences only in early satiety, nausea and vomiting (P < 0.05).

CONCLUSION: Type 2 diabetic patients have a significantly higher prevalence of upper GI symptoms, and delayed gastric emptying may contribute to these symptoms. Ultrasound is convenient in detecting the gastric emptying of diabetic patients.

Diabetes mellitus and anal sphincter pressures: an experimental model in rats

PURPOSE

Symptoms of the gastrointestinal tract, frequent in patients with diabetes mellitus, which may be related to an increase in the production of free radicals, include alterations in the function of the sphincter anal musculature. Such alterations are characterized by a decrease of muscular tone associated with different degrees of fecal incontinence. This study was performed to show the alterations in the anal sphincter pressures of diabetic rats and to evaluate the role of nitric oxide and oxidative stress in this situation.

METHODS

Male Wistar rats weighing 250 to 400 g were used. The animals were divided in two groups: control and diabetic. Diabetes was induced through intraperitoneal injection of streptozotocin and the anal pressures were gauged by anorectal manometry. Nitric oxide was evaluated through measures of nitrites and nitrates, and oxidative stress through the technique of chemoluminescence.

RESULTS

There was a significant decrease in the sphincter anal pressure of diabetic animals 60 days after induction (P < 0.05). This pressure returned to basal values after administration of a nitric oxide synthase antagonist. The levels of nitrites and nitrates as well as of lipoperoxidation were significantly increased in the diabetic compared with the control group (P < 0.05).

CONCLUSIONS

In this study, hyperglycemia of diabetes mellitus caused an increase in the oxidative stress. Apparently the elevation of nitric oxide levels was one of the responsible factors for the decrease of anal sphincter pressures.

Seventy-five gram glucose tolerance test to assess carbohydrate malabsorption and small bowel bacterial overgrowth

AIM: To investigate non-invasively the incidence of absorption of carbohydrates in diabetic patients during an oral glucose tolerance test (OGTT) and to determine whether malabsorption may be associated with insulin secretion and insulin resistance.

METHODS: A standard 75-g OGTT was performed in 82 diabetic patients. The patients received 75 g of anhydrous glucose in 225 mL of water after an overnight fasting and breath samples were collected at baseline and up to 120 min after ingestion. Breath hydrogen and methane concentrations were measured. Blood glucose and serum insulin concentrations were measured before ingestion and at 30, 60, 90, 120 min post-ingestion.

RESULTS: When carbohydrate malabsorption was defined as subjects with an increase of at least 10 ppm (parts per million) in hydrogen or methane excretion within a 2-h period, 28 (34%) had carbohydrate malabsorption. According to the result of increased breath test, 21 (75%) patients were classified as small bowel bacterial overgrowth and 7 (25%) as glucose malabsorption. Patients with carbohydrate malabsorption were older and had poor glycemic control as compared with those without carbohydrate malabsorption. The HOMA value, the sum of serum insulin during the test and the Δinsulin/Δglucose ratio were greater in patients with carbohydrate malabsorption.

CONCLUSION: Insulin resistance may be overestimated by using these markers if the patient has carbohydrate malabsorption, or that carbohydrate malabsorption may be present prior to the development of insulin resistance. Hence carbohydrate malabsorption should be taken into account for estimating insulin resistance and β-cell function.

Upper gastrointestinal sensory-motor dysfunction in diabetes mellitus

Gastrointestinal (GI) sensory-motor abnormalities are common in patients with diabetes mellitus and may involve any part of the GI tract. Abnormalities are frequently sub-clinical, and fortunately only rarely do severe and life-threatening problems occur. The pathogenesis of abnormal upper GI sensory-motor function in diabetes is incompletely understood and is most likely multi-factorial of origin. Diabetic autonomic neuropathy as well as acute suboptimal control of diabetes has been shown to impair GI motor and sensory function. Morphological and biomechanical remodeling of the GI wall develops during the duration of diabetes, and may contribute to motor and sensory dysfunction. In this review sensory and motility disorders of the upper GI tract in diabetes is discussed; and the morphological changes and biomechanical remodeling related to the sensory-motor dysfunction is also addressed.

Opportunities afforded by the study of unmyelinated nerves in skin and other organs

Neurological practice is mainly focused on signs and symptoms of disorders that involve functions governed by myelinated nerves. Functions controlled by unmyelinated nerve fibers have necessarily remained in the background because of the inability to consistently stain, image, or construct clinically applicable neurophysiological tests of these nerves. The situation has changed with the introduction of immunohistochemical methods and confocal microscopy into clinical medicine, as these provide clear images of thin unmyelinated nerves in most organs. One obvious sign of change is the increasing number of reports from several laboratories of the pathological alterations of cutaneous nerves in skin biopsies from patients with a variety of clinical conditions. This study reviews recent methods to stain and image unmyelinated nerves as well as the use of these methods for diagnosing peripheral neuropathy, for experimental studies of denervation and reinnervation in human subjects, and for demonstrating the vast array of unmyelinated nerves in internal organs. The new ability to examine the great variety of nerves in different organs opens opportunities and creates challenges and responsibilities for neurologists and neuroscientists.

Effects of an aldose reductase inhibitor on gastroenteropathy in streptozotocin-diabetic rats

We investigated the effects of epalrestat, an aldose reductase inhibitor (ARI), on gastric emptying, fecal water content, and electrolyte transport in distal colon in streptozotocin (STZ)-induced diabetic rats. We measured gastric emptying time by acetaminophen method and short-circuit-current (Isc) in colonic mucosa using an Ussing chamber. The Isc in response to electric-field-stimulation (EFS) was decreased in untreated rats due to suppression by Cl- secretion. ARI treatment alleviated this suppression (2.7 +/- 0.6 vs. 7.4 +/- 1.1 microA/0.38 cm2 at 8 weeks after treatment, 1.1 +/- 0.2 vs. 7.0 +/- 1.0 at 12 weeks after treatment, P<0.05). In addition, the percentage of fecal water content in untreated rats was significantly lower than in ARI-treated rats (58.0 +/- 2.0 vs. 67.6 +/- 0.8% at 8 weeks, 56.9 +/- 2.1 vs. 63.4 +/- 1.4 at 12 weeks, P<0.05). From STZ injection to 8 weeks, the serum levels of acetaminophen in the diabetic rats were significantly lower than in controls, indicating delayed gastric emptying. At 12 weeks in the diabetic rats treated with ARI, the serum levels of acetaminophen were significantly higher than in the untreated diabetic rats (6.6 +/- 0.4 vs. 3.5 +/- 0.5 microg/ml, P<0.05). ARI-treatment ameliorated delayed gastric emptying without improving glycemic control. These findings show that ARI partially prevented progression of impaired gastric emptying, ion transport, and water transport, and suggest that epalrestat might be useful in the treatment of diabetic gastroenteropathy.

Gastrointestinal disturbances in diabetes

Gastrointestinal disorders are common in patients with diabetes mellitus. As many as 75% of patients visiting diabetes clinics will report significant gastrointestinal (GI) symptoms. The symptom complex experienced may vary widely. Many patients go undiagnosed and undertreated. Patients with a history of retinopathy, nephropathy, or neuropathy should be presumed to have GI abnormalities until proven otherwise. The workup should start with a thorough patient history and appropriate laboratory, radiographic, and GI testing. In addition to pharmacologic therapy, glycemic control and dietary manipulation play an important role in managing GI disorders in people with diabetes.

Small intestinal glucose absorption and duodenal motility in type 1 diabetes mellitus

OBJECTIVE

Small intestinal glucose absorption is increased in animal models of diabetes mellitus, but little data are available in humans. Small intestinal motility is reported to be frequently abnormal in patients with diabetes and could potentially affect glucose absorption. Our aim was to evaluate small intestinal glucose absorption and duodenal motor responses to intraduodenal nutrients, in patients with type 1 diabetes and controls.

METHODS

Eight type 1 patients (two with autonomic neuropathy) and nine controls were studied during euglycemia. A manometric catheter was positioned across the pylorus, and nutrient infused intraduodenally (90 kcal over 30 min), followed by a bolus of 3-O-methylglucose (3-OMG). Blood was sampled to measure glucose and 3-OMG concentrations.

RESULTS

During nutrient infusion, the number of duodenal waves did not differ between patients and controls. After the infusion, patients with diabetes had more propagated duodenal wave sequences (p < 0.05). The area under the plasma 3-OMG curve did not differ between the groups but correlated with both the blood glucose concentration at the time of 3-OMG administration (r = 0.64, p < 0.005) and the number of duodenal waves (r = 0.52, p < 0.05) and antegrade propagated duodenal sequences (r = 0.51, p < 0.05) preceding the 3-OMG bolus.

CONCLUSIONS

During euglycemia, duodenal motor responses to small intestinal nutrient are comparable in patients with relatively uncomplicated type 1 diabetes and healthy subjects, but duodenal motility after nutrient infusion is increased in patients. Small intestinal glucose absorption is similar in patients and controls, but may be dependent on the blood glucose concentration and duodenal motor activity.

The effect of ranitidine on the pharmacokinetics of rosiglitazone in healthy adult male volunteers

BACKGROUND

Rosiglitazone is an insulin-sensitizing oral agent in the thiazolidinedione class used to treat patients with type 2 diabetes mellitus. It binds to peroxisome proliferator-activated receptor gamma in liver, muscle, and adipose tissue. Ranitidine, a histamine2-receptor antagonist, may be prescribed for patients with type 2 diabetes and esophageal symptoms such as heartburn. By raising gastrointestinal pH levels, ranitidine may affect the bioavailability of coadministered drugs.

OBJECTIVES

This article presents the absolute bioavailability of rosiglitazone, as well as the effects of ranitidine on the pharmacokinetics of rosiglitazone.

METHODS

Healthy men were enrolled in a randomized, open-label, 4-period, period-balanced crossover study of rosiglitazone and ranitidine. All individuals received each of 4 regimens successively, separated by a 4-day washout period: a single IV dose of rosiglitazone 2 mg administered alone over 1 hour; a single IV dose of rosiglitazone 2 mg administered over 1 hour on the fourth day of treatment with oral ranitidine 150 mg given every 12 hours; a single oral dose of rosiglitazone 4 mg alone; and a single oral dose of rosiglitazone 4 mg on the fourth day of treatment with oral ranitidine 150 mg given every 12 hours. The primary end point was dose-normalized area under the plasma concentration-time curve from time 0 to infinity (AUC(0-infinity)). Maximum observed plasma concentration (Cmax), the time at which Cmax occurred (Tmax), plasma clearance (CL), steady-state volume of distribution (Vss), and terminal elimination half-life (t 1/2) were also assessed.

RESULTS

Twelve individuals were enrolled. The absolute bioavailability of rosiglitazone was 99%. For AUC(0-infinity), the point estimate and the associated 95% CI for the ratio of ranitidine + IV rosiglitazone to IV rosiglitazone alone was 1.02 (range, 0.88-1.20). With oral rosiglitazone, the AUC(0-infinity) point estimate (95% CI) for the ratio of ranitidine + rosiglitazone to rosiglitazone alone was 0.99 (range, 0.85-1.16). Cmax, Tmax, t 1/2, Vss and CL of rosiglitazone, whether administered orally or intravenously, were unaffected by ranitidine. Oral and IV rosiglitazone were associated with a favorable safety profile and were well tolerated with or without concurrent ranitidine treatment.

CONCLUSIONS

In this study of 12 healthy adult male volunteers, the absolute bioavailability of rosiglitazone was 99%, and the oral and IV single-dose pharmacokinetics of rosiglitazone were unaltered by concurrent treatment with ranitidine.

Domperidone is more effective than cisapride in children with diabetic gastroparesis

BACKGROUND

Disorders of gastrointestinal motility are commonly detected in patients with insulin-dependent diabetes mellitus and are associated with significant morbidity. They contribute to poor metabolic control of diabetes.

AIM

To assess the effect of an 8-week course of domperidone or cisapride on gastric electrical activity, gastric emptying time and dyspeptic symptoms in children with insulin-dependent diabetes mellitus and gastroparesis.

METHODS

Dyspeptic symptoms were assessed by a score system, gastric emptying time was measured by ultrasonography and gastric electrical activity was obtained by electrogastrography. Fourteen children received domperidone and 14 received cisapride. The median (range) ages were 11.6 years (5-15 years) and 12 years (6-16.9 years), respectively. Symptom assessment, ultrasonography and electrogastrography were repeated at the end of the trial. Fasting and fed (180 min after feeding) glycaemia and haemoglobin A, C (HbA1c) levels were also measured.

RESULTS

At the end of the trial both groups showed a significant decrease in symptomatic score; however, the score was markedly lower in the domperidone group than in the cisapride group (P < 0.01). Domperidone was significantly more effective than cisapride in reducing the gastric emptying time (P < 0.05), normalizing gastric electrical activity (P < 0.05) and decreasing the prevalence of episodes of gastric dysrhythmia (P < 0.01). Domperidone was also more effective than cisapride in improving diabetic metabolic control. No potentially drug-related adverse effects occurred.

CONCLUSIONS

In children with insulin-dependent diabetes mellitus complicated by dyspeptic symptoms and gastroparesis, domperidone is superior to cisapride in reversing gastric emptying delay and gastric electrical abnormalities, as well as in improving dyspeptic symptoms and diabetic metabolic control.

Evaluation of gut motility in type II diabetes by the radiopaque marker method

BACKGROUND

The clinical usefulness of the radiopaque marker method for detecting diabetic gastrointestinal motility disturbances, was evaluated by examining 21 type II diabetes subjects who did not have any neuropathic symptoms.

METHODS

After administration of a Sitzmark capsule, markers were located using plain abdominal radiographs, and the transit time of the markers through seven areas of digestive tract was calculated by Arhan's methods. The plasma concentration of acetaminophen at 45 min after oral administration was measured to evaluate gastric emptying time. The coefficient of variation of R-R intervals on the electrocardiograms (CV(R-R)) was measured to evaluate parasympathetic autonomic function.

RESULTS

In the diabetics, the average (+/- SD) transit time through upper digestive tracts was slightly but not significantly elongated compared with control subjects (14.4 +/- 8.3 vs 9.9 +/- 6.1 h). Significant elongation was observed in transit time through the lower digestive tracts or the whole gut (44.6 +/- 20.9 and 57.9 +/- 22.3 h, respectively) compared with control subjects (23.3 +/- 8.5 and 33.2 +/- 11.0 h). The transit time of the markers from stomach to small intestine was highly correlated (r = 0.693) with plasma concentration of acetaminophen. The transit time through either the whole colon (r = 0.564) or the whole gut (r = 0.630) was highly correlated with CV(R-R).

CONCLUSIONS

These findings suggest that the radiopaque marker method is a useful tool for detecting the sections of the digestive tract responsible for gut motility disturbances. In type II diabetics with no neuropathic symptoms, the lower digestive tracts may deteriorate prior to the impairment of upper digestive tracts.

Severe respiratory depression in a patient with gastroparesis while receiving opioids for pain

OBJECTIVE

To increase awareness of the possibility of severe respiratory depression when oral opioids are used in patients with gastrointestinal motility disorders.

SETTING

A major county hospital affiliated with a university.

PATIENT

A patient with severe pain from diabetic muscle necrosis with a history of gastroparesis.

INTERVENTIONS

Attempted pain control with oral and transdermal opioids.

RESULTS AND CONCLUSIONS

Pain control in our patient was attempted using potent oral opioids on two occasions. However, this patient suffered severe respiratory depression after each attempt. Transdermal delivery of fentanyl eventually provided satisfactory pain relief without side effects. We conclude that patients with gastrointestinal motility disorders may be at high risk for side effects of oral opioids due to altered absorption kinetics. Suggestions are made for alternative strategies for opiate delivery in patients with gastrointestinal motility disorders.

Cisapride-induced torsades de pointes

Two cases of torsades de pointes associated with cisapride are presented, both in association with concomitant drug therapy that inhibits cisapride biotransformation. In one case, plasma cisapride was elevated days after the event, strongly supporting a role for accumulation of the drug in causing the arrhythmia. It is emphasized that these adverse drug reactions are not idiosyncratic, but rather are predictable based on an understanding of the underlying mechanisms.