Shohei Tanaka

Alcohol and smoking affect risk of uncomplicated colonic diverticulosis in Japan.

Colonic diverticula are located predominantly on the right side in Asia and on the left side in Europe and the United States. Factors associated with uncomplicated colonic diverticulosis and its distribution pattern have been unknown. Our aims are to investigate the prevalence and risk factors for uncomplicated colonic diverticulosis. We conducted a prospective cross-sectional study in adults who underwent colonoscopy. Alcohol, alcohol related flushing, smoking, medications, and comorbidities were assessed by interview on the colonoscopy day. Alcohol consumption was categorized as nondrinker, light (1–180 g/week), moderate (181–360 g/week), and heavy (≥361 g/week). Smoking index was defined as the number of cigarettes per day multiplied by the number of smoking years and categorized as nonsmoker, <400, 400–799, and ≥800. A total of 2,164 consecutive patients were enrolled. Overall, 542 patients (25.1%) had uncomplicated colonic diverticulosis located on the right side (50%), bilaterally (29%), and on the left side (21%). Univariate analysis revealed age, male, smoking index, alcohol consumption, aspirin use, anticoagulants use, corticosteroid use, hypertension, and atherosclerotic disease as factors significantly associated with diverticulosis. Alcohol related flushing was not associated with the disease. Multivariate analysis showed increasing age (P<0.01), increasing alcohol consumption (P<0.01) and smoking (P<0.01), and atherosclerotic disease (P<0.01) as significantly associated factors. Alcohol and smoking were associated with right-sided and bilateral diverticula. In conclusion, one in four Japanese adults have colonic diverticulosis (50% right-sided). Age, alcohol consumption, and smoking were found to be significant risk factors for uncomplicated colonic diverticulosis, particularly right-sided and bilateral.

Colonic diverticular hemorrhage associated with the use of nonsteroidal anti-inflammatory drugs, low-dose aspirin, antiplatelet drugs, and dual therapy.

The effects of various medications on lower gastrointestinal tract remains unknown. Here, we investigated the effects of nonsteroidal anti‐inflammatory drugs (NSAIDs), low‐dose aspirin, and antiplatelet drugs associated with diverticular bleeding.

Predictors for identification of stigmata of recent hemorrhage on colonic diverticula in lower gastrointestinal bleeding.

Goals: The aim of this study was to identify predictors for the identification of stigmata of recent hemorrhage (SRH) on colonic diverticula. Background: Several factors influence the identification of SRH in the diagnosis of colonic diverticular bleeding. Study: A total of 396 patients hospitalized for lower gastrointestinal bleeding were analyzed. Comorbidities, medications, timing of colonoscopy [<24 h (h); urgent, 24 to 48 h, >48 h], preparation, expert colonoscopist, use of a cap, use of a water-jet scope, total colonoscopy, and procedure time (over 60 min) were assessed. A multivariable logistic regression model was used to estimate odds ratio (OR) and 95% confidence interval (CI). Results: Two hundred fifteen patients were diagnosed with colonic diverticular bleeding and 37 (17%) were identified with SRH. Urgent colonoscopy (OR, 8.4; 95% CI, 2.3-30; P<0.01), expert colonoscopist (OR, 3.0; 95% CI, 1.2-7.3; P=0.02), use of a cap (OR, 3.4; 95% CI, 1.4-8.0; P=0.01), and use of water-jet scope (OR, 5.8; 95% CI, 2.3-15; P<0.01) were found to be independent predictive factors for SRH. The accuracy of these factors in combination was 0.90 (95% CI, 0.85-0.96) as measured by area under the receiver operating characteristic curve (ROC-AUC). SRH identification rate was higher in the urgent (22%) than in the 24 to 48 hours (2.9%, P<0.01) and >48 hours groups (1.0%, P<0.01), showing a tendency to decrease with time (P<0.01 for trend). Conclusions: Factors of urgent colonoscopy, expert colonoscopist, use of a cap, and use of water-jet scope are useful for identifying SRH diverticula.

Effects of osmotic-release methylphenidate in attention-deficit/hyperactivity disorder as measured by event-related potentials

Aim:  Attention‐deficit/hyperactivity disorder (ADHD) is a relatively common central nervous system disorder in school‐age children, which may involve a specific disorder in cognition and/or information processing. Event‐related potentials (ERP) are commonly used as physiological measures of cognitive function as they are easily measured and non‐invasive. Thus, in the present study, we examined the effects of osmotic‐release methylphenidate (MPH) (Concerta), a common treatment for childhood attention‐deficit/hyperactivity disorder (ADHD), in ADHD children as measured by ERP.

Risk of peptic ulcer bleeding associated with Helicobacter pylori infection, nonsteroidal anti-inflammatory drugs, low-dose aspirin, and antihypertensive drugs: A case-control study

The associations between antithrombotic or antihypertensive drugs and peptic ulcer bleeding (PUB) remain unknown, particularly in Asia, where Helicobacter pylori infection is prevalent. This study aims to evaluate the risks of PUB from antithrombotic drugs, angiotensin II receptor blockers (ARBs), angiotensin‐converting enzyme (ACE) inhibitors, calcium channel blockers, α‐blockers, and β‐blockers.

Impact of HIV infection on colorectal tumors: a prospective colonoscopic study of Asian patients.

Background:Non-AIDS defining cancer has recently become a major problem in HIV-infected patients. Little has been reported on whether HIV infection is a risk factor for colorectal adenoma, especially in Asians. Methods:The study was conducted under a prospective cross-sectional design and included all adults who underwent colonoscopy. Subjects were matched by age and sex to compare the prevalence of colorectal adenoma, adenocarcinoma, polyps, and other tumors. Detailed risk factors were assessed, including lifestyle habits, medications, comorbidities, gastrointestinal symptom rating scale, HIV-associated factors, and human papillomavirus infection. To evaluate the effects of HIV infection on adenoma, the odds ratio (OR) was estimated by multivariate logistic regression. Results:A total of 177 HIV-infected patients and 177 controls were selected for analysis. No significant difference was noted in the prevalence of adenoma (n = 29 vs. 40, P = 0.14). Multivariate analysis adjusted by baseline demographics and risk factors showed that HIV is not associated with increased risk of adenoma (adjusted OR = 0.66, P = 0.16). Kaposi’s sarcoma was more common in HIV-infected patients (n = 6 vs. 0, P = 0.03). Among HIV-infected patients, advanced age was an independent and significant risk factor for adenoma (adjusted OR = 2.28, P < 0.01). CD4 count, HIV-RNA, history of antiretroviral treatment, and oncogenic human papillomavirus infection were not risk factors for adenoma. Conclusions:HIV infection was not identified as risk for adenoma in Asian patients. However, advanced age was independently associated with increased risk of adenoma. HIV-infected patients should not miss screening opportunity for colorectal adenoma and other gastrointestinal malignancies.

Event-related potentials reflect the efficacy of pharmaceutical treatments in children and adolescents with attention deficit/hyperactivity disorder.

Few objective biological measures of pharmacological treatment efficacy exist for attention deficit/hyperactivity disorder (ADHD). Although we have previously demonstrated that event-related potentials (ERPs) reflect the effects of osmotic-release methylphenidate in treatment of naïve pediatric patients with ADHD, whether this is true for the therapeutic effects of atomoxetine (ATX) is unknown. Here, we used the Japanese version of the ADHD rating-scale IV to evaluate 14 patients with ADHD, and compared their ERP data with 14 age- and sex-matched controls. We measured P300 and mismatch negativity (MMN) components during an auditory oddball task before treatment (treatment naïve) and after 2 months of ATX treatment. Compared with controls, P300 components at baseline were attenuated and prolonged in the ADHD group at Fz (fronto-central), Cz (centro-parietal), Pz (parietal regions), C3 and C4 electrodes. ATX treatment reduced ADHD symptomology, and after 2 months of treatment, P300 latencies at Fz, Cz, Pz, C3, and C4 electrodes were significantly shorter than those at baseline. Moreover, MMN amplitudes at Cz and C3 electrodes were significantly greater than those at baseline. Thus, ERPs may be useful for evaluating the pharmacological effects of ATX in pediatric and adolescent patients with ADHD.

Comparison of pervasive developmental disorder and schizophrenia by the Japanese version of the National Adult Reading Test

Abstract Objective. In adults, it is sometimes difficult to discriminate between pervasive developmental disorder (PDD) and schizophrenia (SCH) when positive symptoms are not outstanding. We examined whether the Japanese version of the National Adult Reading Test (JART), is a valid scale for evaluating pre-morbid intelligence quotient (IQ) in patients with SCH, and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) are useful for helping to discriminate between PDD and SCH. Methods. Sixteen patients with adult PDD and 16 age-, education- and sex-matched patients with SCH participated in the present study. In addition, two groups were matched for JART and GAF scores. All subjects were scored on the JART and WAIS-R after informed consent on the aim of this study. Examiners who were blind to the diagnoses measured JART and WAIS-R. Results. Significant diagnosis-by-IQ examination interactions were found (F[1,30] = 10.049, P = 0.003). Furthermore, WAIS-R scores of the PDD group were higher than those of the SCH group (P = 0.002) considering two groups were matched for JART. Conclusions. The comparison of IQ in the PDD group and in the SCH group by JART and WAIS-R might be an easy and useful method for helping to discriminate between PDD and SCH.

Reduced Prefrontal Cortex Hemodynamic Response in Adults with Methamphetamine Induced Psychosis: Relevance for Impulsivity.

Patients with methamphetamine abuse/dependence often exhibit high levels of impulsivity, which may be associated with the structural abnormalities and functional hypoactivities observed in the frontal cortex of these subjects. Although near-infrared spectroscopy (NIRS) is a simple and non-invasive method for characterizing the clinical features of various psychiatric illnesses, few studies have used NIRS to directly investigate the association between prefrontal cortical activity and inhibitory control in patients with methamphetamine-induced psychosis (MAP). Using a 24-channel NIRS system, we compared hemodynamic responses during the Stroop color-word task in 14 patients with MAP and 21 healthy controls matched for age, sex and premorbid IQ. In addition, we used the Barrett Impulsivity Scale-11 (BIS-11) to assess impulsivity between subject groups. The MAP group exhibited significantly less activation in the anterior and frontopolar prefrontal cortex accompanied by lower Stroop color-word task performance, compared with controls. Moreover, BIS-11 scores were significantly higher in the MAP group, and were negatively correlated with the hemodynamic responses in prefrontal cortex. Our data suggest that reduced hemodynamic responses in the prefrontal cortex might reflect higher levels of impulsivity in patients with MAP, providing new insights into disrupted inhibitory control observed in MAP.

Event-Related Potentials Correlate with the Severity of Child and Adolescent Patients with Attention Deficit/Hyperactivity Disorder

Background: Attention deficit/hyperactivity disorder (ADHD) symptoms can continue through adolescence and adulthood, including difficulty in staying focused, paying attention, and controlling behavior, as well as hyperactivity. While children and adolescents with ADHD have functional impairments at multiple dimensions, there are no objective biological indicators to assess the severity of ADHD. Event-related potentials (ERPs) are widely used as a noninvasive method for evaluating sensory and cognitive processes involved in attention tasks. Previous studies have shown that P300 amplitude or latency, a main component in ERPs, is altered in patients with ADHD. However, little is known about the relationship between P300 and the severity of ADHD symptoms. Method: We sought to measure both P300 amplitude and latency in ERPs during auditory oddball tasks in 44 patients with ADHD (mean age ± SD 10.28 ± 3.43 years) and 15 age- and gender-matched normally developing children (11.40 ± 3.02 years). In ADHD patients, we also assessed symptom severity using the ADHD rating scale-IV-Japanese version. Result: In ADHD groups, P300 amplitude and latency were attenuated and prolonged compared to controls at the frontocentral, centroparietal, and parietal positions. Furthermore, levels of P300 latency at these positions are positively correlated with the inattention subscale scores measured by the ADHD rating scale-IV-Japanese version. Conclusions: The present study revealed that the degree of P300 latency might reflect the severity of ADHD symptoms with children and adolescents, suggesting that ERPs are a useful technique to evaluate the severity of ADHD symptoms.