Kazuhiro Yoshiuchi

Comorbidity of Irritable Bowel Syndrome, Panic Disorder, and Agoraphobia in a Japanese Representative Sample

OBJECTIVES:Irritable bowel syndrome (IBS) is considered to be a transcultural functional bowel disorder with high comorbidity and psychiatric disorders; but well-designed epidemiologic studies have never been performed in Japan. The purpose of this study was to establish the prevalence of IBS, together with the comorbidity rates of panic disorder (PD) and agoraphobia, employing a large-scale survey based on stratified random sampling.METHOD:A total of 4,000 subjects aged 20–69 years completed a questionnaire and the results were weighted to ensure representativeness of the Japanese general population. The questionnaire covered key symptoms of IBS, PD, and agoraphobia. The prevalence of IBS and its subtypes was calculated by gender. The comorbidity of PD and agoraphobia with IBS was compared with morbidity in non-IBS subjects; and comorbidity in IBS subjects who had consulted medical practitioners regarding their symptoms and in those who had not was also compared.RESULTS:The prevalence of IBS was 6.1% in total. It was significantly higher in females than in males. Diarrhea-predominant IBS was more prevalent in males and constipation-predominant IBS in females. The morbidity rates of PD and agoraphobia were significantly higher in IBS than in non-IBS subjects. Comorbidity did not differ between female and male IBS subjects, while morbidity was significantly higher in female than in male non-IBS subjects; and comorbidity did not differ between consulter and nonconsulter subjects.CONCLUSIONS:The prevalence of IBS and its comorbidity with PD and agoraphobia in Japan were demonstrated to be similar to those reported in Western industrialized countries.

Of Mice and Men — Universality and Breakdown of Behavioral Organization

Mental or cognitive brain functions, and the effect on them of abnormal psychiatric diseases, are difficult to approach through molecular biological techniques due to the lack of appropriate assay systems with objective measures. We therefore study laws of behavioral organization, specifically how resting and active periods are interwoven throughout daily life, using objective criteria, and first discover that identical laws hold both for healthy humans subject to the full complexity of daily life, and wild-type mice subject to maximum environmental constraints. We find that active period durations with physical activity counts successively above a predefined threshold, when rescaled with individual means, follow a universal stretched exponential (gamma-type) cumulative distribution, while resting period durations below the threshold obey a universal power-law cumulative distribution with identical parameter values for both of the mammalian species. Further, by analyzing the behavioral organization of mice with a circadian clock gene (Period2) eliminated, and humans suffering from major depressive disorders, we find significantly lower parameter values (power-law scaling exponents) for the resting period durations in both these cases. Such a universality and breakdown of the behavioral organization of mice and humans, revealed through objective measures, is expected to facilitate the understanding of the molecular basis of the pathophysiology of neurobehavioral diseases, including depression, and lay the foundations for formulating a range of neuropsychiatric behavioral disorder models.

Reliability of recalled self‐report on headache intensity: investigation using ecological momentary assessment technique

Recalled evaluation of headache intensity is often affected by several factors. Recently, computerized ecological momentary assessment (EMA) has been developed to avoid such problems as recall bias. Here, we compared recalled headache intensity with momentary headache intensity using EMA in tension- type headache (TTH). Forty patients with TTH wore watch-type computers for 1 week to record momentary headache intensity and also rated their headache intensities by recall. We calculated intraclass correlation coefficients between recalled headache intensity and indices from EMA recordings in the whole study population and in two subgroups divided by variability of momentary headache intensity. The results showed that consistency and agreement of momentary and recalled headache intensity were low, and this was especially marked in the subjects whose headache varied widely. These observations suggested that variability of headache intensity may affect recall of headache intensity and this should be taken into consideration in both clinical and research settings.

Symptom profile of multiple chemical sensitivity in actual life.

Objective: This study was conducted to confirm the definition of multiple chemical sensitivity (MCS) in actual life: that multiple symptoms are provoked in multiple organs by exposure to, and ameliorated by avoidance of, multiple chemicals at low levels. We used the Ecological Momentary Assessment to monitor everyday symptoms and the active sampling and passive sampling methods to measure environmental chemical exposure. Methods: Eighteen patients with MCS, diagnosed according to the 1999 consensus criteria, and 12 healthy controls participated in this study. Fourteen patients and 12 controls underwent 1-week measurement of physical and psychologic symptoms and of the levels of exposure to various chemicals. Linear mixed models were used to test the hypotheses regarding the symptom profile of MCS patients. Results: Some causative chemicals were detected in 11 of 14 MCS patients. Two other patients did not report any hypersensitivity episodes, whereas passive sampling showed far less exposure to chemicals than control subjects. Another subject reported episodic symptoms but was excluded from the following analyses because no possible chemical was detected. Eleven of the 17 physical symptoms and all four mood subscales examined were significantly aggravated in the interview based on “patient-initiated symptom prompts.” On the other hand, there were no differences in physical symptoms or mood subscales between MCS patients and control subjects in the interview based on “random prompts.” Conclusions: MCS patients do not have either somatic or psychologic symptoms under chemical-free conditions, and symptoms may be provoked only when exposed to chemicals. AS = active sampling; AS–PS method = active sampling and passive sampling methods; CAS = the concentration of exposure estimated by the AS method; CFS = chronic fatigue syndrome; CPS = the concentration of exposure estimated by the PS method; CS = chemical sensitivity; DAMS = Depression and Anxiety Mood Scale; DNPH = 2,4-dinitrophenyl-hydrazine; ED = electronic diary; EESI = Environmental Exposure and Sensitivity Inventory; EMA = Ecological Momentary Assessment; FM = fibromyalgia; M.I.N.I. = Mini International Neuropsychiatric Interview; MCS = multiple chemical sensitivity; PS = passive sampling; RSD = relative standard deviation; RSDAS = RSD of repeatability test in the AS method; RSDPS = RSD of repeatability test in the PS method; VOCs = volatile organic compounds.

A real-time assessment of the effect of exercise in chronic fatigue syndrome

Patients with chronic fatigue syndrome (CFS) report substantial symptom worsening after exercise. However, the time course over which this develops has not been explored. Therefore, the objective of this study was to investigate the influence of exercise on subjective symptoms and on cognitive function in CFS patients in natural settings using a computerized ecological momentary assessment method, which allowed us to track the effects of exercise within and across days. Subjects were 9 female patients with CFS and 9 healthy women. A watch-type computer was used to collect real-time data on physical and psychological symptoms and cognitive function for 1week before and 2weeks after a maximal exercise test. For each variable, we investigated temporal changes after exercise using multilevel modeling. Following exercise, physical symptoms did get worse but not until a five-day delay in CFS patients. Despite this, there was no difference in the temporal pattern of changes in psychological symptoms or in cognitive function after exercise between CFS patients and controls. In conclusion, physical symptoms worsened after several days delay in patients with CFS following exercise while psychological symptoms or cognitive function did not change after exercise.

Clinical effects of blood pressure biofeedback treatment on hypertension by auto-shaping

Objective Although biofeedback has been reported to be efficacious in the treatment of hypertension, the degree of response has varied. This study investigated the mechanisms of blood pressure reduction by biofeedback. Method: Thirty outpatients with essential hypertension (10 men and 20 women) aged 38 to 65 years were studied. Subjects were randomly assigned to group A or B. Subjects in group A underwent biofeedback treatment once a week for a total of four sessions. Those in group B self-monitored their blood pressure during the sessions as the control period and later underwent the same biofeedback treatment. Results: Blood pressure measured by doctor was reduced by 17 +/- 18/8 +/- 7 (p <.01) and elevation of pressure induced by mental stress testing was suppressed by 8 +/- 9 (p <.05)/4 +/- 8 during the treatment period in group A (mm Hg). In group B, both blood pressure measured by doctor and elevation of pressure by mental stress testing remained unchanged during the control period and they were later suppressed by 20 +/- 15/9 +/- 7 (p <.01) and 11 +/- 10 (p <.05)/5 +/- 9 by the biofeedback treatment. Self-monitored pressure in both groups tended to decrease by the biofeedback treatment. Systolic and diastolic pressures as well as pulse rate decreased, skin temperature increased, and alpha-wave amplitude on electroencephalography increased during the therapy (p <.05). Conclusion: This treatment was effective in suppressing the pressor response to stress. Patients whose blood pressure increases with stress may be suited for biofeedback intervention.

Eating attitudes and body dissatisfaction in adolescents: Cross‐cultural study

Aims:  Sociocultural factors are thought to be important in the pathogenesis of eating disorders. However, there have been few studies comparing eating behavior among various cultural populations. The aim of the present study is to compare attitudes towards bodyweight and shape, and desire for thinness in Japanese male and female subjects with those in people from other countries and of different ethnic origin.

Development of a hand-held personal digital assistant-based food diary with food photographs for Japanese subjects.

Hand-held personal digital assistant (PDA)-based food diaries have been developed for self-monitoring of dietary intake, but the accuracy of these diaries is unclear for patients with diabetes. The aim of the study was to assess the accuracy and feasibility of use of a new PDA-based food diary, including food photographs. The study included 44 Japanese participants without diabetes (mean age 23 years) and 16 Japanese patients with type 2 diabetes (mean age 53 years). The PDA-based food diary was used for 7 consecutive days. Information about all dietary intake on the 7th day of PDA self-monitoring was collected by a 24-hour recall interview on the 8th day. The PDA-based data for dietary intake on the 7th day were then compared to the 24-hour recall data for the same period. Feasibility was assessed based on the frequency and timeliness of self-monitoring. There was no significant difference in daily totals for energy, protein, carbohydrate, and fat between the two methods in each group. Pearsons correlation and intraclass correlation coefficients showed strong significant relationships for all variables between the two methods in both groups. Bland-Altman plots did not indicate any bias in estimated daily caloric intake. Participants recorded 98% of their meals in the PDA, with 75% of entries recorded within 6 hours after the meal starting time. The findings suggest that the PDA-based food diary is a potential clinical method to estimate dietary intake and may be a beneficial tool for self-monitoring of dietary intake.

Enhanced persistency of resting and active periods of locomotor activity in schizophrenia.

Patients with schizophrenia frequently exhibit behavioral abnormalities associated with its pathological symptoms. Therefore, a quantitative evaluation of behavioral dynamics could contribute to objective diagnoses of schizophrenia. However, such an approach has not been fully established because of the absence of quantitative biobehavioral measures. Recently, we studied the dynamical properties of locomotor activity, specifically how resting and active periods are interwoven in daily life. We discovered universal statistical laws (“behavioral organization”) and their alterations in patients with major depressive disorder. In this study, we evaluated behavioral organization of schizophrenic patients (n = 19) and healthy subjects (n = 11) using locomotor activity data, acquired by actigraphy, to investigate whether the laws could provide objective and quantitative measures for a possible diagnosis and assessment of symptoms. Specifically, we evaluated the cumulative distributions of resting and active periods, defined as the periods with physical activity counts successively below and above a predefined threshold, respectively. Here we report alterations in the laws governing resting and active periods; resting periods obeyed a power-law cumulative distribution with significantly lower parameter values (power-law scaling exponents), whereas active periods followed a stretched exponential distribution with significantly lower parameter values (stretching exponents), in patients. Our findings indicate enhanced persistency of both lower and higher locomotor activity periods in patients with schizophrenia, probably reflecting schizophrenic pathophysiology.

QT interval and QT dispersion in eating disorders

Background: Eating disorders are thought to be risk factors for cardiac sudden death secondary to arrhythmia. Results in previous studies on QT interval and QT dispersion, markers of fatal arrhythmia, have been inconsistent. Methods: We prospectively examined 179 female eating disorder patients, being over 18 years old and diagnosed according to the DSM-IV criteria between January 1995 and December 2002, and 52 healthy women. Patients with abnormal plasma electrolytes or taking medications that might influence the electrocardiogram (ECG) were excluded from the study. QT intervals were corrected for heart rate using Bazett’s formula and the nomogram method, which is more reliable at extremely low heart rates than Bazett’s formula. QT dispersion was measured as the difference between the longest and shortest QT intervals. QT intervals and QT dispersion in each patient group were compared with those in the control group. Results: The 164 eligible patients consisted of 43 patients with anorexia nervosa restricting type, 35 with anorexia nervosa binge eating/purging type, 63 with bulimia nervosa purging type, and 23 with bulimia nervosa nonpurging type. There was no significant difference in age between eating disorder patients and controls. QT interval and QT dispersion were significantly longer in all eating disorder subtypes than in the control group. QT interval and QT dispersion were significantly correlated with the rate of body weight loss in bulimia nervosa. Conclusions: QT interval and QT dispersion were prolonged in both anorexia nervosa and bulimia nervosa. Examination of ECG in eating disorder patients without extremely low body weight also appears to be clinically important.