Objectives The purpose of this study was to examine the epidemiological features of self-injury in Japan, and to investigate the factors associated with a history of self-injury, using nationwide random sample data on Japan in 2010.
Methods Questionnaires were distributed to 2,693 subjects, aged 16–49 years, randomly selected from the all over Japan using 2-stage stratified random sampling; the answers regarding self-injury were analyzed. Potential risk factors were compared between those who answered that they had a history of self-injury (self-injury group) and those who answered that they did not (non-self-injury group).
Results Responses were obtained from 1,540 participants (response rate, 57.2%). Lifetime prevalence of having 1 or more self-injury events was 7.1% overall (3.9% for men; 9.5% for women) and approximately half of them reported a repetitive history of self-injury. Lifetime prevalence of self-injury was highest in those aged 16–29 years (9.9%, 16–29 years; 5.6%, 30–39 years; 5.7%, 40–49 years). Lifetime prevalence among women (16–29 years, 30–39 years, and 40–49 years) decreased with age (15.7%, 7.5%, and 5.8%, respectively), however, that among men increased with age (3.0%, 3.4%, and 5.5%, respectively). Compared with the non-self-injury group, those in the self-injury group were significantly more likely to have a history of cigarette smoking (self-injury group, 47.5%; non-self-injury group, 28.2%; adjusted odds ratio [95% confidence interval]: 2.18 [1.32–3.58]), childhood abuse (23.6% and 3.7%, respectively, 4.24 [2.18–8.25]), induced abortion (30.3% and 12.7%, respectively, 1.93[1.13–3.30]); moreover, they were significantly less likely to answer that they had a happy life when they were junior high school students (41.1% and 78.6%, respectively, 0.45[0.25–0.79]). In addition, those in the self-injury group were more likely to report a history of parental divorce, that they did not have good communication with their parents, and that they did not have respect and appreciation for their parents; however, these factors were not significant after adjustment.
Conclusion These results are consistent with those of previous research reports in which the lifetime prevalence of self-injury was high among women aged 16–29 years, and in which self-injury was more likely to occur among individuals who had a history of cigarette smoking and childhood abuse. Such individuals should be provided care to prevent self-injury. In addition, from a social point of view, research examining family environments including these factors is required.

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Objectives The objective of this study was to assess the prevalence of subjective daytime sleepiness among the community-dwelling elderly population in Japan using the Japanese version of the Epworth Sleepiness Scale (JESS) and to investigate the correlates of excessive daytime sleepiness (EDS).
Methods Subjects aged 65 years or older, born between April and September, living independently, who resided in 1 district of Tokyo, Japan, were recruited. A total of 3195 subjects meeting the inclusion criteria were mailed a questionnaire that inquired about the JESS, socio-demographic factors, and health-related factors. Of the 2034 elderly individuals who responded to the survey (response rate, 63.7%), 1494 subjects (652 men, 842 women) who completely answered the questionnaire were included in the study (valid response rate, 46.8%).
Results The mean (±standard deviation) JESS score was 5.0±3.8 (men 5.6±4.1, women 4.4±3.4, P<0.01). The prevalence of EDS (a cut-off score>10) was 8.8% (men 12.7%, women 5.7%, P<0.01). The male gender, being employed, having poor mental health and well-being, having lowered activity of daily living (ADL), or having subjective memory impairment were significantly associated with EDS. In the gender-specific models, low social network and subjective memory impairment in men, whereas obesity and lowered ADL in women, were significantly associated with EDS.
Conclusion EDS was more frequently observed in men than in women among the community-dwelling elderly population in Japan. A substantial gender difference was found in correlates of EDS. This finding is useful in the clinical management of patients who complain of daytime sleepiness; moreover, it is useful for the management of public health.

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Objectives To make recommendations on the revision of the Pandemic Influenza National Action Plan and Guidelines, we reviewed the data from the flu call center and medical institutions in Kobe city and compared them with data from Ibaraki prefecture.
Methods The overall duration of study from May 2009 to December 2009 was divided into 4 periods; we analyzed details of the calls received by the call center and examined the correlation between them and cases who were seen at medical institutions in Kobe. We used a mathematical model to approximate the cumulative growth curve of the number of calls received by the call center and the number of cases attending fever clinics in Kobe. We compared the above data with data from Ibaraki because the total number of confirmed cases of pandemic (H1N1) 2009 influenza was similar: Kobe identified the first confirmed case of the influenza in Japan, while Ibaraki reported their first case 1 month later.
Results Following the report of the initial domestic case, the Kobe call center received 30,067 calls in a month. A “delayed sigmoid curve” fitted well for both the rise in the number of calls at the call center and of cases attending the fever clinics. “Feeling sick despite no overseas travel history” was the most common reason for call. More than 2,000 calls/day were received, and the responses to such calls were instructions to consult a general medical institution (40%), instructions to refer to a fever clinic (8%), guidance on home care or how to manage underlying disorders, and listening to callers' anxieties and complaints. The numbers of calls decreased towards the end of July; the number of calls increased again when outbreaks were reported in schools and a death due to influenza was confirmed. After November, on an average, 500 calls/day were received; most were complaints regarding vaccination. Unlike Kobe, Ibaraki did not experience a surge in the number of calls to the call center or consultations to fever clinics within a short period of time.
Conclusion The outbreak of pandemic (H1N1) 2009 influenza showed different call patterns and medical consultations in different regions. The time of disease outbreak and the availability of medical resources differ among regions; hence, each municipality should act practically and flexibly according to the situation in their locality.

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Objectives The frequency of food poisoning from fresh seafood in Japan in 2009 and the regional characteristics and causative factors of such poisoning require investigation. In all cases, no bacterial or viral pathogens have been detected, although sliced raw flounder (sashimi) was suspected as being causative by the food sanitation inspectors. However, the cause of these poisonings is still unknown, and comprehensive approaches are required to completely understand the problem.
Methods In order to obtain information on these poisonings, we sent a questionnaire to all 136 autonomies in Japan. It was found that many patients had contracted such poisoning. Symptoms included vomiting/nausea, diarrhea, and abdominal pain. Symptoms generally began within 12 hours of eating fresh seafood and resolved by the next day. The period of this survey was from January 1, 2009 to December 31, 2009. We analyzed the data by year and month and investigated the regional incidence.
Results The response rate was 72.8% (99/136). Seventy autonomies answered “yes” and the remaining 29 answered “no.” There were 57 cases of definite and 171 cases of suspected food poisoning. Since 2003, the number of poisonings has increased annually, and they occur throughout the year, although they are most common in September in all autonomies. The highest incidence (53.9%) was reported for August, September, October, and November.
Conclusion Food poisoning of unknown origin from fresh seafood in Japan shows seasonal characteristics, being more common during the hot seasons than in the cold seasons. When a pathogenic substance is not discovered, it is very difficult to confirm food poisoning, which is why the number of suspected cases was 3 times that of the confirmed.

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Objectives The Dietary Record by Cooked Dishes (DRcd) method, which enables simple assessment of food and nutrient intake, is unique because it uses a nutrient database of cooked dishes. Although this method has been validated among the rural Japanese populations for which the database was developed, the applicability of the DRcd for other populations is unclear. In this study, we have examined the applicability of DRcd among an urban population.
Methods Subjects were selected from among patients who underwent cancer screening between 2004 and 2006 at the Research Center for Cancer Prevention and Screening, National Cancer Center, Japan. Subjects aged 40–69 years, who lived in Tokyo and the surrounding suburbs, were stratified into groups by sex and age. A total of 144 men and women agreed to participate in the study after random selection. Subjects were instructed to keep 4-day dietary records (4d-DR) of all consumed foods and beverages, including dish names, and all dishes were then coded using DRcd codes on the basis their names. The intake of 17 food groups and 40 nutrients was estimated using the dish-based nutrient composition table of the DRcd. Simultaneously, 4d-DR were used to calculate dietary intake independently, which served as a reference. We examined the applicability of the DRcd method using percentage difference and Pearson's correlation coefficients for intakes estimated using 4d-DR and the DRcd. Moreover, the results were compared to those of a previous study.
Results A total of 88% of the recorded dishes matched the dish codes of the DRcd database by name. Pearson's correlation coefficient scores of 0.6 or higher were observed for 12 and 10 food groups, and for 34 and 27 nutrients in men and women, respectively. Notably, the intake of majority of the nutrients tended to be underestimated, a difference that was more pronounced in men. In comparison with a previous study, the percentage differences and Pearson's correlation coefficient scores for intake tended to be lower in our study.
Conclusion As the correlation coefficients (0.6) were high for a majority of food groups and nutrients estimated by DRcd, the DRcd method may be applicable for urban populations. However, regional intake data may be necessary for the estimation of absolute value for the intake of some nutrients.

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