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Dive into the research topics where Fehmi Ates is active.

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Featured researches published by Fehmi Ates.


Nephrology | 2005

Psychiatric disorders and large interdialytic weight gain in patients on chronic haemodialysis

Hulya Taskapan; Fehmi Ates; Burhanettin Kaya; Murat Emul; Mine Kaya; Cagatay Taskapan; Ibrahim Sahin

Aims:  Psychiatric disorders have been considered in terms of non‐compliant behaviour and low life quality in haemodialysis patients. The aim of this study is to investigate the potential association of psychiatric disorders with compliance of fluid restriction and nutritional status and to measure the effects of psychiatric disorders on the life quality in chronic renal failure patients on haemodialysis.


Gastroenterology | 2015

Mucosal Impedance Discriminates GERD From Non-GERD Conditions

Fehmi Ates; Elif Saritas Yuksel; Tina Higginbotham; James C. Slaughter; Jerry E. Mabary; Robert T. Kavitt; C. Gaelyn Garrett; David O. Francis; Michael F. Vaezi

BACKGROUND & AIMS Current diagnostic tests for gastroesophageal reflux disease (GERD) are suboptimal and do not accurately and reliably measure chronicity of reflux. A minimally invasive device has been developed to assess esophageal mucosal impedance (MI) as a marker of chronic reflux. We performed a prospective longitudinal study to investigate MI patterns in patients with GERD and common nonreflux conditions, to assess MI patterns before and after treatment with proton pump inhibitors and to compare the performance of MI and wireless pH tests. METHODS We evaluated MI in 61 patients with erosive esophagitis, 81 with nonerosive but pH-abnormal GERD, 93 without GERD, 18 with achalasia, and 15 with eosinophilic esophagitis. MI was measured at the site of esophagitis and at 2, 5, and 10 cm above the squamocolumnar junction in all participants. MI was measured before and after acid suppressive therapy, and findings were compared with those from wireless pH monitoring. RESULTS MI values were significantly lower in patients with GERD (erosive esophagitis or nonerosive but pH-abnormal GERD) or eosinophilic esophagitis than in patients without GERD or patients with achalasia (P < .001). The pattern of MI in patients with GERD differed from that in patients without GERD or patients with eosinophilic esophagitis; patients with GERD had low MI closer to the squamocolumnar junction, and values increased axially along the esophagus. These patterns normalized with acid suppressive therapy. MI patterns identified patients with esophagitis with higher levels of specificity (95%) and positive predictive values (96%) than wireless pH monitoring (64% and 40%, respectively). CONCLUSIONS Based on a prospective study using a prototype device, measurements of MI detect GERD with higher levels of specificity and positive predictive values than wireless pH monitoring. Clinical Trials.gov, Number: NCT01556919.


Digestive Diseases and Sciences | 2006

The relationship of heart rate variability with severity and prognosis of cirrhosis.

Fehmi Ates; Ergun Topal; Feridun Kosar; Melih Karincaoglu; Bulent Yildirim; Yuksel Aksoy; Murat Aladag; Murat Harputluoglu; Ulvi Demirel; Hakan Alan; Fatih Hilmioglu

Many studies have demonstrated that cirrhosis is frequently associated with autonomic dysfunction. The aim of this study was to test autonomic dysfunction in cirrhotic patients by analyzing heart rate variability (HRV), to determine whether or not the degree of autonomic dysfunction is correlated with the severity of disease, and, also, to compare the changes of HRV between survivor and nonsurvivor groups after 2-year follow-up periods. HRV was analyzed using 24-hr ECG recording in 30 cirrhotic patients and 28 normal controls. The changes in HRV parameters including mean normal-to-normal (N-N) interbeat intervals (mean NN), standard deviation of all N-N intervals (SDNN), standard deviation of the average of N-N intervals for each 5-min period over 24 hr (SDANN), root mean square succesive differences (r-MSSD; msec), and percentage of adjacent N-N intervals that are >50 msec apart (pNN50), all as time domain parameters, were evaluated. The cirrhotic patients were also evaluated according to Child-Pugh classification scores as markers of the disease severity. The time-domain measures of HRV in cirrhotic patients were significantly reduced compared with those in the control group (for all parameters; P < 0.001). The severity of disease was associated with reduced HRV measures (for all parameters; P < 0.001). After the 2-year follow-up periods, HRV measurements in cirrhotic patients were significantly much lower in nonsurvivors than in survivors (P < 0.001 for all). We conclude that increasing severity of cirrhosis is associated with a reduction in HRV. This finding may be an indicator of poor prognosis and mortality for cirrhosis.


World Journal of Gastroenterology | 2011

Impact of liver steatosis on response to pegylated interferon therapy in patients with chronic hepatitis B

Fehmi Ates; Mehmet Yalniz; Saadet Alan

AIM To evaluate the impact of liver steatosis upon response to given therapy in chronic hepatitis B (CHB) patients. METHODS 84 consecutive CHB patients treated with 48-wk PEGylated interferon (PEG-IFN) therapy were enrolled. Baseline characteristics and sustained viral response (SVR) to PEG-IFN therapy were evaluated. RESULTS Mean body mass index (BMI) was 27.36 ± 4.4 kg/m². Six (7.1%) had hypertension and three (3.5%) had diabetes mellitus. Steatosis was present in 22.6% (19/84) of liver biopsy samples. Age, BMI, and triglyceride levels of the patients with hepatic steatosis were significantly higher than those without hepatic steatosis (P < 0.05). SVR to PEG-IFN therapy was 21.4% (18/84). Sixteen of these 18 CHB patients with SVR (88.9%) did not have any histopathologically determined steatosis. On the other hand, only two of the 19 CHB patients with hepatic steatosis had SVR (10.5%). Although the SVR rate observed in patients without steatosis (16/65, 24.6%) was higher compared to those with steatosis (2/19, 10.5%), the difference was not statistically significant (P > 0.05). CONCLUSION Occurrence of hepatic steatosis is significantly high in CHB patients and this association leads to a trend of decreased, but statistically insignificant, SVR rates to PEG-IFN treatment.


Angiology | 2007

QT Interval Analysis in Patients With Chronic Liver Disease: A Prospective Study

Feridun Kosar; Fehmi Ates; Ibrahim Sahin; Melih Karincaoglu; Bulent Yildirim

In previous studies, it has been shown that QT interval prolongation is related to an increased mortality rate in chronic liver disease (CLD). But QT dispersion (QTd) and its clinical significance in CLD has not been well studied. The objectives of this study were to investigate the relation between QTd and severity of the disease and determine its prognostic value in cirrhotic patients. Thirty-three consecutive patients with cirrhosis and 35 sex- and age-matched healthy subjects were studied. QT intervals and QT dispersions were measured on admission, and all intervals were corrected for heart rate according to Bazetts formula. The authors analyzed the potential relationship between QT parameters and the disease severity according to Child-Pugh classification and compared these values between survivors and nonsurvivors after a 3-year follow-up. Child-Pugh classification is used to assess liver function in cirrhosis. Corrected QT (QTc) prolongations were found in 32% of patients with cirrhosis and 5.7% of the healthy controls (p <0.001). The prevalence of increased (>70 ms) corrected QT dispersion (QTcd) was 45% in patients with cirrhosis. According to Child-Pugh criteria: QTd, maximum QT interval (QTmax), corrected QTmax (QTcmax), and QTcd in class C were significantly higher than those of class A and B (p <0.05, for all comparison). But there was no significant difference between class A and B in QTmax, QTcmax, QTd, and QTcd. There were 10 (30%) deaths from all causes during 3-year follow-up in the study group. Cox regression analysis showed that QTd and QTcd were better mortality indicators than QTmax and QTcmax, and Childs classification was the best predictor for mortality among all variables. In conclusion, QT dispersion and corrected QT dispersion parameters were better mortality indicators than other QT interval parameters and also may give additional prognostic information in patients with chronic liver disease.


Gut and Liver | 2015

The Pathogenesis and Management of Achalasia: Current Status and Future Directions

Fehmi Ates; Michael F. Vaezi

Achalasia is an esophageal motility disorder that is commonly misdiagnosed initially as gastroesophageal reflux disease. Patients with achalasia often complain of dysphagia with solids and liquids but may focus on regurgitation as the primary symptom, leading to initial misdiagnosis. Diagnostic tests for achalasia include esophageal motility testing, esophagogastroduodenoscopy and barium swallow. These tests play a complimentary role in establishing the diagnosis of suspected achalasia. High-resolution manometry has now identified three subtypes of achalasia, with therapeutic implications. Pneumatic dilation and surgical myotomy are the only definitive treatment options for patients with achalasia who can undergo surgery. Botulinum toxin injection into the lower esophageal sphincter should be reserved for those who cannot undergo definitive therapy. Close follow-up is paramount because many patients will have a recurrence of symptoms and require repeat treatment.


Pancreas | 2005

QT interval analysis in patients with acute biliary pancreatitis.

Fehmi Ates; Feridun Kosar; Yuksel Aksoy; Bulent Yildirim; Ibrahim Sahin; Fatih Hilmioglu

Background: It has been previously proposed that electrocardiographic abnormalities may be associated with acute pancreatitis. However, there is a lack of data on the QT interval and dispersion value in patients with acute pancreatitis, and no data are also available concerning QT interval and QT dispersion in acute biliary pancreatitis (ABP). Aims: We aimed to investigate the QT parameters in patients with ABP, to compare them with those of healthy controls, and to analyze the relationship between QT parameters and Ranson score. Methods: The present study included 32 patients with acute biliary pancreatitis and 35 healthy controls. The severity of the pancreatitis was determined by Atlanta criteria: fewer than 3 Ranson criteria or fewer than 8 APACHE II (the Acute Physiology and Chronic Health Evaluation) points indicated the mild disease (group 1); 3 or more Ranson criteria or 8 or more APACHE II points or organ failure or systemic complications or local complications indicated the severe disease (group 2). On admission, all patients underwent a standard 12-lead electrocardiogram, and corrected maximum QTc interval (QTcmax), corrected minimum QT interval (QTcmin), and corrected QTc dispersion (QTcd) values of the subjects were measured according to the Bazett formula in this study. Results: QTcmax and QTcd were significantly longer in patients with ABP than in healthy controls (442 ± 38 milliseconds versus 413 ± 34 milliseconds, P < 0.05; and 67 ± 21 milliseconds versus 42 ± 18 milliseconds, P < 0.001, respectively). Similarly, QTcmax and QTcd were significantly longer in group 2 than in group 1 (440 ± 38 milliseconds versus 450 ± 34 milliseconds, P < 0.01; and 66 ± 9 milliseconds versus 71 ± 11 milliseconds, P < 0.01, respectively). Correlation analysis showed that there is a significant positive relationship between Ranson scores of patients and QTcmax and QTcd (P < 0.01 and P < 0.001, respectively). Conclusion: The effect of acute biliary pancreatitis on QT intervals and dispersion appears to be dependent not only on the disease but also on its severity, and these parameters may give additional prognostic information in ABP patients, even in the initial evaluation.


Diseases of The Esophagus | 2016

Randomized controlled trial comparing esophageal dilation to no dilation among adults with esophageal eosinophilia and dysphagia

Robert T. Kavitt; Fehmi Ates; James C. Slaughter; Tina Higginbotham; B. D. Shepherd; Eric Sumner; Michael F. Vaezi

The role of esophageal dilation in patients with esophageal eosinophilia with dysphagia remains unknown. The practice of dilation is currently based on center preferences and expert opinion. The aim of this study is to determine if, and to what extent, dysphagia improves in response to initial esophageal dilation followed by standard medical therapies. We conducted a randomized, blinded, controlled trial evaluating adult patients with dysphagia and newly diagnosed esophageal eosinophilia from 2008 to 2013. Patients were randomized to dilation or no dilation at time of endoscopy and blinded to dilation status. Endoscopic features were graded as major and minor. Subsequent to randomization and endoscopy, all patients received fluticasone and dexlansoprazole for 2 months. The primary study outcome was reduction in overall dysphagia score, assessed at 30 and 60 days post-intervention. Patients with severe strictures (less than 7-mm esophageal diameter) were excluded from the study. Thirty-one patients were randomized and completed the protocol: 17 randomized to dilation and 14 to no dilation. Both groups were similar with regard to gender, age, eosinophil density, endoscopic score, and baseline dysphagia score. The population exhibited moderate to severe dysphagia and moderate esophageal stricturing at baseline. Overall, there was a significant (P < 0.001) but similar reduction in mean dysphagia score at 30 and 60 days post-randomization compared with baseline in both groups. No significant difference in dysphagia scores between treatment groups after 30 (P = 0.93) or 60 (P = 0.21) days post-intervention was observed. Esophageal dilation did not result in additional improvement in dysphagia score compared with treatment with proton pump inhibitor and fluticasone alone. In patients with symptomatic esophageal eosinophilia without severe stricture, dilation does not appear to be a necessary initial treatment strategy.


Best Practice & Research in Clinical Gastroenterology | 2013

Approach to the patient with presumed extraoesophageal GERD

Fehmi Ates; Michael F. Vaezi

Reflux related cough, asthma and laryngitis are frequently encountered and are considered part of extraoesophageal syndromes. The diagnosis of extraoesophageal reflux is difficult due to the lack of gold standard diagnostic criteria. Esophagogastroduodenoscopy and esophageal pH monitoring are inadequate diagnostic tools for due to poor sensitivity and specificity. For this reason, empirical PPI therapy is recommended as an initial approach to diagnose and treat the potential underlying cause of these symptoms in patients without alarm symptoms. Diagnostic testing with esophageal pH and/or impedance monitoring and esophageal motility testing is usually reserved for those who continue to be symptomatic despite a trial of therapy with PPIs. Recent developments have increased our understanding of this difficult to treat group of patients but more research into reflux related extraoesophageal symptoms are needed to better diagnose and treat this group.


Current Treatment Options in Gastroenterology | 2014

New Approaches to Management of PPI-Refractory Gastroesophageal Reflux Disease

Fehmi Ates; Michael F. Vaezi

Opinion statement“Refractory GERD” is one the most common misnomers in the area of gastroesophageal reflux disease. The term implies reflux as the underlying etiology despite unresponsiveness to aggressive, often twice-daily proton pump inhibitor therapy. The term should be replaced with “refractory symptoms.” We must acknowledge that in many patients, symptoms of reflux often overlap with non-GERD causes such as gastroparesis, dyspepsia, hypersensitive esophagus, and functional disorders. Lack of response to aggressive acid suppressive therapy often leads to esophagogastroduodenoscopy followed by pH or impedance monitoring. In the majority of patients these tests are normal. The role of non-acid reflux measured by impedance pH testing in this group is uncertain at best and the results from this test alone should not be used to refer patients to surgical fundoplication. In patients unresponsive to acid suppressive therapy, reflux is most commonly not causal and a search for non-GERD causes must ensue.

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Michael F. Vaezi

Vanderbilt University Medical Center

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Tina Higginbotham

Vanderbilt University Medical Center

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Elif Saritas Yuksel

Vanderbilt University Medical Center

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