Risk Factors for Abdominal Pain-Related Disorders of Gut-Brain Interaction in Adults and Children: A Systematic Review.

BACKGROUND & AIMS: Many studies have assessed risk factors of irritable bowel syndrome (IBS) and other abdominal pain-related disorders of gut-brain interaction (AP-DGBI); however, the role of these factors is unclear due to heterogeneous study designs. The aim of this systematic review was to extensively evaluate the literature and determine clinical risk and protective factors for the presence and persistence of AP-DGBI in children and adults. METHODS: A PubMed search identified studies investigating potential risk and protective factors for AP-DGBI in adults and children. Inclusion criteria included fully published studies with a control group; exclusion criteria included poor-quality studies (using a validated scale). For each factor, the proportion of studies that found the factor to be a risk factor, protective factor, or neither was summarized. The number of studies, diagnostic criteria, number of subjects, and average study quality rating provided further context. Whenever possible, a meta-analysis generated pooled odds ratios or mean difference. RESULTS: The systematic review included 348 studies. Female sex, gastroenteritis, abuse, stress, psychological disorders, somatic symptoms, and poor sleep were consistent risk factors for developing AP-DGBI in adults and children. In adults, additional risk factors included obesity, smoking, and increased use of medical resources. Protective AP-DGBI factors in adults included social support and optimism; no studies for protective factors were found for children. CONCLUSIONS: There are multiple risk factors for AP-DGBI in adults and children. These include female sex, gastroenteritis, abuse, stress, poor sleep, obesity, psychological disorders, and somatic symptoms. Additional studies are needed in children, on protective factors, and on factors associated with persistence of AP-DGBI.

Colonic mucosal microbiota is associated with bowel habit subtype and abdominal pain in patients with irritable bowel syndrome.

Mucosal microbiota differ significantly from fecal microbiota and may play a different role in the pathophysiology of irritable bowel syndrome (IBS). The aims of this study were to determine if the composition of mucosal microbiota differed between IBS, or IBS bowel habit (BH) subtypes, and healthy controls (HCs). Sigmoid colon mucosal biopsies were obtained from 97 Rome-positive patients with IBS (28% IBS-constipation, 38% IBS-diarrhea, 24% IBS-mixed, and 10% IBS-unsubtyped) and 54 HCs, from which DNA was extracted. 16S rRNA gene sequencing and microbial composition analysis were performed. Group differences in α and ß diversity and taxonomic level differences were determined using linear regression while controlling for confounding variables. IBS BH subtype was associated with microbial α diversity (P = 0.0003) with significant differences seen in the mucosal microbiota of IBS-constipation versus IBS-diarrhea (P = 0.046). There were no significant differences in α or ß diversity in the mucosal microbiota of IBS versus HCs (P = 0.29 and 0.93, respectively), but metagenomic profiling suggested functional differences. The relative abundance of Prevotella_9 copri within IBS was significantly correlated with increased abdominal pain (r = 0.36, P = 0.0003), which has not been previously reported in IBS. Significant differences in the mucosal microbiota were present within IBS BH subtypes but not between IBS and HCs, supporting the possibility of IBS BH subtype-specific pathogenesis. Increased Prevotella copri may contribute to symptoms in patients with IBS.NEW & NOTEWORTHY Gut mucosal microbiota differs significantly from fecal microbiota in irritable bowel syndrome (IBS) and may play a different role in its pathophysiology. Investigation of colonic mucosal microbiota in the largest cohort of patients with IBS and healthy controls accounting for confounding variables, including diet demonstrated significant differences in mucosal microbiota between IBS bowel habit subtypes but not between IBS and healthy controls. In addition, the study reported gut microbiota is associated with abdominal pain in patients with IBS.

Gender and Other Factors Associated with Endoscopy Volume Among U.S. Gastroenterology Fellows.

Gastroenterology (GI) fellows' ability to perform procedures are evaluated by the level of competency in the cognitive and technical components of procedures in Accreditation Council for Graduate Medical Education-accredited fellowship programs.1 However, competency in endoscopic procedures correlates with the number of procedures performed.2 The American Society for Gastrointestinal Endoscopy has recommended that a minimum of 130 esophagogastroduodenoscopies (EGDs) and 275 colonoscopies be performed before procedural competency can be assessed.3 Few studies have examined program or trainee-related factors, such as trainee gender, that may influence procedural volume. In other procedural subspecialties, a gender gap exists in trainee procedural volumes, with female residents performing fewer surgical cases than males.4,5 However, whether gender-related disparities exist in endoscopy volume among GI trainees is unknown. The primary aim of this study was to determine the impact of GI fellow gender on endoscopic procedural volume during training. Secondary aims were to determine if fellow career choice or other training program-related factors, such as program size, location, or setting, affect procedure volume during fellowship.

Effect of Exclusion Diets on Symptom Severity and the Gut Microbiota in Patients With Irritable Bowel Syndrome.

BACKGROUND & AIMS: Altered fecal microbiota have been reported in irritable bowel syndrome (IBS), although studies vary, which could be owing to dietary effects. Many IBS patients may eliminate certain foods because of their symptoms, which in turn may alter fecal microbiota diversity and composition. This study aimed to determine if dietary patterns were associated with IBS, symptoms, and fecal microbiota differences reported in IBS. METHODS: A total of 346 IBS participants and 170 healthy controls (HCs) completed a Diet Checklist reflecting the diet(s) consumed most frequently. An exclusion diet was defined as a diet that eliminated food components by choice. Within this group, a gluten-free, dairy-free, or low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols diet was further defined as restrictive because they often are implicated in reducing symptoms. Stool samples were obtained from 171 IBS patients and 98 HCs for 16S ribosomal RNA gene sequencing and microbial composition analysis. RESULTS: Having IBS symptoms was associated with consuming a restrictive diet (27.17% of IBS patients vs 7.65% of HCs; odds ratio, 3.25; 95% CI, 1.66-6.75; P value = .006). IBS participants on an exclusion or restrictive diet reported more severe IBS symptoms (P = .042 and .029, respectively). The composition of the microbiota in IBS patients varied depending on the diet consumed. IBS participants on an exclusion diet had a greater abundance of Lachnospira and a lower abundance of Eubacterium (q value, <.05), and those on a restrictive diet had a lower abundance of Lactobacillus (q value, <.05). CONCLUSIONS: Restrictive diets likely are consumed more by IBS patients than HCs to reduce GI symptom severity. Dietary patterns influence the composition of the fecal microbiota and may explain some of the differences between IBS and HCs.

Chances of Renal Recovery or Liver Transplantation After Hospitalization for Alcoholic Liver Disease Requiring Dialysis.

BACKGROUND: Acute kidney injury in the setting of alcoholic liver disease portends a poor prognosis without liver transplant. AIMS: Using a tertiary care population, we aimed to evaluate the outcomes of renal replacement therapy in patients with alcoholic liver disease and acute kidney injury with < 6 months sobriety. METHODS: A retrospective review of hospitalized patients with alcoholic hepatitis/acute on chronic alcoholic cirrhosis and hepatorenal syndrome or acute tubular necrosis was performed. Analyzed variables included patient comorbidities, mode of dialysis, MELD-Na score, CLIF-C ACLF score, and CLIF-C OF score. RESULTS: Forty-seven patients were included, 21.3% of which survived 6 months of sobriety to be eligible for transplant evaluation. Despite renal replacement therapy, mortality was 78.7%. Of survivors, 4 received transplants and 6 recovered without transplant. Lower CLIF-C ACLF (p < 0.001) and CLIF-C OF (p = 0.001) predicted 6-month survival and lower MELD-Na (p = 0.016), CLIF-C ACLF (p < 0.001), and CLIF-C OF (p = 0.006) predicted renal recovery. There was no difference in survival or renal recovery between etiologies of kidney injury. Modality of initial dialysis with intermittent hemodialysis compared to continuous renal replacement therapy predicted improved survival (41.2 vs. 10.0%, p = 0.01) and nearly reached significance for renal recovery (23.5 vs. 6.7%, p = 0.054). CONCLUSIONS: Although severe alcoholic liver disease with acute kidney injury is associated with a high mortality irrespective of the etiology of renal failure, over 20% of patients in this study survived 6 months to be evaluated for liver transplant and 12.8% recovered renal function. These outcomes should be considered when weighing the decision of initiating dialysis.

An Urban Center Experience Exploring Barriers to Adherence to Endoscopic Surveillance for Non-Dysplastic Barrett's Esophagus.

Background Data regarding barriers to Barrett's esophagus (BE) surveillance is limited. Studying an urban center population, we aimed to characterize non-dysplastic BE surveillance rates and identify health, racial, and socioeconomic disparities affecting surveillance. Methods Patients with biopsy-confirmed BE were retrospectively identified between January 2002 and December 2012. Non-dysplastic BE patients were analyzed for adherence to established surveillance guidelines. Demographic, racial, comorbidities, and socioeconomic variables were extracted. Annual gross income (AGI) was utilized as a marker of socioeconomic status (SES). Univariate and multivariate analyses compared adherent vs. non-adherent patients to surveillance guidelines. Results A total of 217 patients with non-dysplastic BE were analyzed. The majority were male (67.3%) and Caucasian (75.6%), with only 47.5% adherent with the first surveillance endoscopy. Patients with a high average AGI were more likely to be adherent with the initial surveillance endoscopy than those with low AGI (p=0.032). Initial compliance with first surveillance was associated with better surveillance at regular intervals (p=0.001). No significant differences in age, primary language, insurance type, marital status, or Charlson Comorbidity Index (CCI) between adherent and non-adherent patients were found. Conclusions Although overall adherence to guidelines was suboptimal, this study identifies important socioeconomic disparities in the endoscopic surveillance for non-dysplastic BE. Identifying and understanding the barriers to care among these lower socioeconomic groups may ultimately lead to improved screening compliance and early BE detection.

Postmenopausal women with irritable bowel syndrome (IBS) have more severe symptoms than premenopausal women with IBS.

BACKGROUND: Although irritable bowel syndrome (IBS) is more common in women, little is known about the role of hormonal changes and menopause in IBS. This study aimed to evaluate for differences in gastrointestinal (GI) and psychological symptoms between pre- and postmenopausal women with IBS compared to age-matched men with IBS. METHODS: Patients with Rome-positive IBS were identified. Premenopausal women were <45 years of age with regular menses. Postmenopausal women were ≥45 years without menses for at least 1 year. Younger men were <45 years, and older men were ≥45 years. Questionnaires measured severity of IBS symptoms, somatic symptoms, health-related quality of life (HRQOL), and psychological symptoms. Multivariable linear or logistic regressions evaluating relationships between age and sex were performed. KEY RESULTS: 190 premenopausal women (mean age 30.25 years), 52 postmenopausal women (mean age 54.38 years), 190 men <45 years (mean age 30.45 years), and 52 men ≥45 years (mean age 53.37 years) were included. Postmenopausal IBS women had greater severity of IBS symptoms (P = .003) and worse physical HRQOL (P = .048) compared to premenopausal women. No differences were observed between age-matched older and younger IBS men. Constipation increased with age for both sexes but was the principal IBS subtype in women only. CONCLUSIONS AND INFERENCES: Postmenopausal women with IBS have more severe IBS symptoms than premenopausal women, while no comparable age-related changes were seen in IBS men. The modulatory effect of female sex hormones on brain-gut interactions which affect visceral perception and GI function likely contributes to these findings.

Emerging Threat: Changing Epidemiology of Hepatitis A and Acute Kidney Injury.

In the past decade, hepatitis A has been considered a rare disease in the United States, largely due to targeted vaccination of at-risk children. Evolving epidemiology has resulted in decreasing immunity and increasing hepatitis A infections among adults who are more likely to experience severe disease. A surge in outbreaks has been noted in the past 2 years, resulting in a high volume of hepatitis A related hospitalizations and complications in otherwise healthy individuals. The traditional understanding that acute kidney injury is a rare extrahepatic manifestation is being challenged by the resurgence of hepatitis A in a more vulnerable population. This review examines the epidemiologic factors that contributed to current public health concern and the association between hepatitis A and acute kidney injury.

Use of Dietary Management in Irritable Bowel Syndrome: Results of a Survey of Over 1500 United States Gastroenterologists.

BACKGROUND/AIMS: Dietary therapy is increasingly used to manage gastrointestinal (GI) symptoms in patients with irritable bowel syndrome (IBS). We aim to gauge United States gastroenterologists' perceptions of dietary therapies for IBS. METHODS: We distributed a 22-question survey to members of the American College of Gastroenterology. The survey was developed by gastroenterologists and survey methodologists. We collected information pertaining to demographics, providers' interpretation of their patients' views on dietary therapy, and gastroenterologists' perceptions on dietary therapy, and nutritional counseling in IBS. RESULTS: One thousand five hundred and sixty-two (14%) surveys were collected. Nearly 60% of participants reported that patients commonly associate food with GI symptoms. IBS patients most commonly use a trial and error approach followed by a lactose-free and gluten-free diet, and rarely use a low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet on their own. Over half of providers recommend diet therapy to ＞ 75% of IBS patients and most commonly recommend a low FODMAP diet. Only 21% of gastroenterologists commonly refer IBS patients to registered dietitians, and only 30% use GI dietitians. Female providers were more likely than males to recommend dietary changes as the primary mode of therapy (OR, 1.43 [1.09-1.88]; P = 0.009). CONCLUSIONS: Our national survey identified enthusiasm for diet treatment of IBS. While patients infrequently tried a low FODMAP diet on their own, GI providers commonly recommended this diet. Only a minority of GI providers refer their IBS patients to a registered dietitian for nutrition counseling and few refer patients to dietitians with specialized GI training. Female providers were more enthusiastic about diet therapies than males.

Acute Kidney Injury in Patients Undergoing Chronic Hepatitis C Virus Treatment With Ledipasvir/Sofosbuvir.

Ledipasvir-sofosbuvir, a once-a-day, oral combination pill, was approved in 2014 for the treatment of chronic hepatitis C infection. Initial trials did not comment on nephrotoxicity; however, recent data suggest a risk of acute kidney injury (AKI) with the use of the medication. We assessed the rates of AKI in patients undergoing ledipasvir-sofosbuvir in a large, urban tertiary care center. This single-center retrospective observation study included all patients undergoing therapy from October 1, 2014, to October 1, 2015. Rates of AKI, defined by more than a 0.3 mg/dL increase in serum creatinine level, were calculated. Patients were followed 12 weeks after therapy to assess for sustained viral response as well as to assess for improvement of AKI after completion of therapy, defined by less than 0.2 mg/dL above baseline serum creatinine. In total, 197 patients were included in the final analysis who had completed ledipasvir-sofosbuvir therapy and completed laboratory values. Among the patients treated, 38 (19%) had AKI during therapy. An additional 4 (2%) had AKI at the end of therapy. Of the 38 patients who experienced AKI, 20 (53%) had improvement in serum creatinine to less than 0.2 mg/dL above their baseline. When comparing for chronic kidney disease (CKD) stage, those with CKD I or II experienced AKI 17% of the time compared with 47% of the time in CKD III or worse (P = 0.005). Conclusion: AKI was seen in nearly one-fifth of our patients, and patients with CKD stage III or worse are at increased risk. Although ledipasvir-sofosbuvir is generally safe in the general population, close monitoring of renal function is recommended.

A Systematic Review of the Effects of Polyols on Gastrointestinal Health and Irritable Bowel Syndrome.

Polyols are sugar alcohols found in certain fruits, vegetables, and sugar-free sweeteners. They make up a component of the diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, which is gaining popularity in the treatment of patients with irritable bowel syndrome (IBS). We conducted a systematic review to evaluate the effects of polyols on the gastrointestinal tract in healthy men and women and in patients with IBS. Utilizing PubMed, Ovid, and Embase databases, we conducted a search on individual polyols and each of these terms: fermentation, absorption, motility, permeability, and gastrointestinal symptoms. Standard protocols for a systematic review were followed. We found a total of 1823 eligible articles, 79 of which were included in the review. Overall, available work has shown that polyol malabsorption generally occurs in a dose-dependent fashion in healthy individuals, and malabsorption increases when polyols are ingested in combination. However, studies in patients with IBS have shown conflicting results pertaining to polyol malabsorption. Polyol ingestion can lead to intestinal dysmotility in patients with IBS. Regarding the microbiome, moderate doses of polyols have been shown to shift the microbiome toward an increase in bifidobacteria in healthy individuals and may therefore be beneficial as prebiotics. However, data are limited regarding polyols and the microbiome in patients with IBS. Polyols can induce dose-dependent symptoms of flatulence, abdominal discomfort, and laxative effects when consumed by both healthy volunteers and patients with IBS. Further research is needed to better understand the effects of specific polyols on gastrointestinal function, sensation, and the microbiome in health and gastrointestinal disorders such as IBS.

Hepatitis C Virus-Associated Aortitis Caused by Type I Cryoglobulins.

Chronic hepatitis C virus infection (HCV) can present with cryoglobulinemic vasculitis, which is primarily associated with type II/III cryoglobulins. Type I cryoglobulins are usually seen in lymphoproliferative disease, and large vessel involvement with this type of vasculitis is rare. A 70-year-old man with chronic HCV presented with abdominal pain, leukocytosis, and rash. Computed tomography angiography showed thickening of the abdominal aorta consistent with large-vessel vasculitis. He was found to have type I cryoglobulinemia and was treated with corticosteroids and ledipasvir/sofosbuvir with rapid resolution of his aortitis. This case emphasizes the need to recognize HCV as a potential etiology of large-vessel vasculitis.

Hepatocellular Carcinoma: A Decade of Hospitalizations and Financial Burden in the United States.

BACKGROUND: Despite a rise in the prevalence of hepatocellular carcinoma (HCC), data on HCC-related hospitalizations and financial burden are limited. The aim of this study was to evaluate temporal trends of HCC-related hospitalizations and evaluate its financial influence. MATERIALS AND METHODS: Patients with the diagnosis of HCC, as reported by International Classification of Diseases-Ninth Revision code, were identified from the National Inpatient Sample databases from 2002-2011. The national estimates of hospitalizations were derived using appropriate sample weights. The change in total average charges per each hospitalization over the study period was calculated after adjusting for inflation. RESULTS: Hospitalizations related to HCC have increased from 24,024 in 2002 to 50,609 in 2011. Of these admissions, HCC was the principal diagnosis in 10,762 and 16,350 subjects in 2002 and 2011, respectively. Most were white males (male: 70%; white: 55%). The overall inpatient mortality was significantly decreased from 13.5% in 2002 to 9.9% in 2011 (P < 0.01). The same trend was also observed for the length of hospital stay (6.5 versus 5.6 days in 2002 and 2011, respectively). The inflation-adjusted cost per hospitalization increased by approximately 47% during the study period. CONCLUSIONS: Despite the decrease in mortality rate and length-of-stay, hospitalizations and financial burden associated with HCC continued to increase between 2002 and 2011 in the United States.

A Perplexing Case of Abdominal Pain That Led to the Diagnosis of Zollinger-Ellison Syndrome.

Zollinger-Ellison syndrome (ZES) is a rare clinical disorder, characterized by hypersecretion of gastric acid and multiple ulcers distal to the duodenal bulb. This occurs via the release of gastrin by neuroendocrine tumors known as gastrinomas. Patients with ZES present with nonspecific GI symptoms, which often leads to a delay in diagnosis. Our patient is a 55-year-old female with chronic abdominal pain, nausea, and diarrhea. She underwent EGD, EUS, MRCP, CT scans, and cholecystectomy, which did not reveal the cause of her symptoms. Repeat EGD showed a cratered ulcer in the second portion of the duodenum, suspicious for ZES. Serum gastrin was initially only moderately elevated while on PPI therapy, but chromogranin A was also elevated. Repeat gastrin level after stopping PPI therapy was 1639 pg/mL. Somatostatin receptor scintigraphy was obtained, which showed two small lesions in the gastrinoma triangle. She subsequently underwent a Whipple pancreaticoduodenectomy and pathology was positive for four microscopic foci of a neuroendocrine tumor. She reported improvement in her symptoms after surgery. This case highlights the need for increased awareness of ZES in patients with unexplained GI complaints and emphasizes the use of multiple modalities in the diagnosis of ZES.

Primary care physicians are under-testing for celiac disease in patients with iron deficiency anemia: Results of a national survey.

BACKGROUND: Iron deficiency anemia (IDA) is a common extra-intestinal manifestation of celiac disease (CD). Little is known about the frequency with which primary care physicians (PCPs) test for CD in patients with IDA. We aimed to describe how PCPs approach testing for CD in asymptomatic patients with IDA. METHODS: We electronically distributed a survey to PCPs who are members of the American College of Physicians. Respondents were asked whether they would test for CD (serologic testing, refer for esophagogastroduodenoscopy [EGD], or refer to GI) in hypothetical patients with new IDA, including: (1) a young Caucasian man, (2) a premenopausal Caucasian woman, (3) an elderly Caucasian man, and (4) a young African American man. These scenarios were chosen to assess for differences in testing for CD based on age, gender, and race. Multivariable logistic regression was used to identify independent predictors of testing. RESULTS: Testing for CD varied significantly according to patient characteristics, with young Caucasian men being the most frequently tested (61% of respondents reporting they would perform serologic testing in this subgroup (p<0.001)). Contrary to guideline recommendations, 80% of respondents reported they would definitely or probably start a patient with positive serologies for CD on a gluten free diet prior to confirmatory upper endoscopy. CONCLUSIONS: PCPs are under-testing for CD in patients with IDA, regardless of age, gender, race, or post-menopausal status. The majority of PCPs surveyed reported they do not strictly adhere to established guidelines regarding a confirmatory duodenal biopsy in a patient with positive serology for CD.

A Rare Case of Gastric Variceal Hemorrhage Secondary to Infiltrative B-Cell Lymphoma.

Portal hypertension commonly arises in the setting of advanced liver cirrhosis and is the consequence of increased resistance within the portal vasculature. Less commonly, left-sided noncirrhotic portal hypertension can develop in a patient secondary to isolated obstruction of the splenic vein. We present a rare case of left-sided portal hypertension and isolated gastric varices in a patient with large B-cell lymphoma, who was treated with splenic artery embolization. The patient is a 73-year-old male with no previous history of liver disease, who presented with coffee ground emesis and melena. On admission to hospital, he was found to have a hemoglobin level of 3.4 g/l. Emergent esophagogastroduodenoscopy showed isolated bleeding gastric varices (IGV1 by Sarin classification) in the fundus and cardia with subsequent argon plasma coagulation injection. He was transferred to our tertiary center where work-up revealed normal liver function tests, and abdominal ultrasound showed patent hepatic/portal vasculature without cirrhosis. MRI demonstrated a large heterogeneously enhancing mass in the pancreatic tail, with invasion into the spleen and associated splenic vein thrombosis. Surgery consultation was obtained, but urgent splenectomy was not recommended. The patient instead underwent splenic artery embolization to prevent future bleeding from his known gastric varices. Pathology from a CT-guided biopsy was consistent with diffuse large B-cell lymphoma. PET imaging showed uptake in the splenic hilum/pancreatic tail region with no additional metastatic involvement. He was evaluated by the Hematology Department to initiate R-CHOP chemotherapy. During his outpatient follow-up, he reported no further episodes of melena or hematemesis. To the best of our knowledge, there have only been two published case reports of large B-cell lymphoma causing upper gastrointestinal bleeding from isolated gastric varices. These cases were treated with splenectomy or chemotherapy alone. Thus far, splenectomy has been the standard treatment approach for splenic vein thrombosis with clinical complication, such as gastric variceal bleeding. We present a case of successful treatment of bleeding isolated gastric varices using a less invasive and less morbid approach through splenic artery embolization. This case highlights the need for an increased awareness of the diverse etiologies of left-sided portal hypertension and isolated gastric varices, as well as the consideration of minimally invasive management strategies.

Abnormal MoCA and normal range MMSE scores in Parkinson disease without dementia: cognitive and neurochemical correlates.

BACKGROUND: The Montreal Cognitive Assessment (MoCA) is increasingly being used as a cognitive screening test in Parkinson disease (PD). The MoCA's popularity likely reflects its ability to detect executive dysfunction, a relative deficiency of the Mini-Mental State Examination (MMSE). OBJECTIVE: To compare neurochemical and neuropsychological functions in non-demented PD patients with mild cognitive impairment (PD-MCI) and without, as defined by MoCA (PD-MCI = MoCA<26). METHODS: Non-demented PD subjects underwent combined MoCA and MMSE, detailed cognitive testing and [¹¹C]methyl-4-piperidinyl propionate acetylcholinesterase and [¹¹C]dihydrotetrabenazine monoaminergic PET imaging. RESULTS: Eighteen subjects met MoCA PD-MCI criteria but had MMSE scores in the normal range, compared to 29 subjects with normal MoCA and MMSE scores. The MoCA-defined PD-MCI group had reduced performance in global cognition (t = 2.91, P = 0.0056), most significantly in executive function (t = 3.18, P = 0.002), as well as significant reduction in dorsal caudate nucleus dopaminergic innervation (t = 2.72, P = 0.009) compared to the PD without MCI group. Both MoCA and MMSE had poor diagnostic accuracy for PD-MCI (65.3%) when using the Level 2 Movement Disorder Society Task Force definition. CONCLUSION: PD subjects with normal range MMSE but abnormal MoCA scores had evidence of caudate nucleus dopaminergic denervation and mild cognitive changes, predominantly in executive function. The MoCA may be able to preferentially detect executive dysfunction compared to the MMSE, but the MoCA has limited diagnostic accuracy for PD-MCI, and should not be used alone to make this diagnosis.