[in Japanese]

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 Attention deficit/hyperactivity disorder (ADHD) is characterized by inattentiveness and /or impulsiveness and hyperactivity, which are unsuited for the developmental stage or age. Although mechanisms leading to the onset of the disease are unclear, this condition seriously hinders childrens' social or learning functions, and recently it was selected as a target disease for a special supporting education program by the Minitry of Education, Culture, Sports, Science and Technology, together with learning disorders and high-functioning pervasive developmental disorders in Japan. In spite of the increasing social interest in ADHD, the epidemiological evidence including data for incidence, prevalence, gender differences, and etiology remain insufficient. In Western countries, as represented by the United States, operational diagnostic criteria such as DSM-IV are widely used and several diagnostic processes using structured interviews have been established. However, the diagnostic criteria have not been consistent even within DSM as shown by DSM-IV and DSM-III-R, and therefore basic epidemiological evidence was not consistent in the previous studies. Regarding the etiology of ADHD, exposure to addictive substances during the pregnancy period caused by maternal smoking or drinking, and familial socioeconomic status are considered important environmental factors. In addition, a family history of mental disorders and polymorphisms of dopamine-related genes such as DRD4 or SLC6A3 have been noted as genetic factors concerning the development of ADHD. However, in Japan, no studies of these subjects or gene-environment interactions have so far been performed. Thus, epidemiological assessment of other than Western populations is needed. In the clinical situation, it is important to grasp the timing of treatment and target problems on the basis of changes of children's ability to control their attention or behavior, and environmental factors associated with growth processes. Especially, comorbidity such as conduct disorder or oppositional defiant disorder is a critical problem. Thus, considering that ADHD is a multifactorial disease, a comprehensive therapic strategy involving medication, education, judicature, and administration should be established for primary and secondary prevention.

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Objective Panel interview surveys of nationally representative elderly people aged 65 years or above in Japan were conducted three times at 2-year intervals since 1999 (Nihon University Japanese Longitudinal Study of Aging) to estimate health expectancy for males and females separately according to their chewing ability.
Method Multistate life table methods were applied to estimate health expectancy. Three health states, namely, active, inactive and dead, were defined according to the ability to perform specified daily activities. Living respondents were considered to be in an “inactive state” if they responded “very difficult” or “unable” for performance of at least one ADL or IADL. Otherwise they were considered to be in an “active state”. 4,323 sampled persons who responded to the baseline survey were included in the study. Based on estimated transition probabilities over the survey period between active and inactive states, and active and inactive states to death, both population- and status-based multistate life tables were constructed according to chewing ability. Those who could chew relatively hard foods at the baseline survey were classified as Group A and those who could chew only relatively soft foods were classified as Group B.
Results The population-based multistate life tables indicated that at age 65, total life expectancy was 19.3/23.2(males/females) years for Group A and 16.7/21.1 years for Group B. Active life expectancy was 16.8/18.6 years and 13.6/16.3 years, and inactive life expectancy was 2.4/4.6 years and 3.1/4.8 years for Groups A and B respectively. A statistically significant difference was observed between the two groups only in terms of active life expectancy. From status-based multistate life tables, similar patterns were observed for those whose status at the baseline was “active”.
Conclusion These results suggest that maintenance or recovery of sufficient chewing ability for elderly people is related to a longer total life expectancy and even more strongly related to a longer active life expectancy.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Purpose An outbreak of adult measles occurring in the eastern part of Ehime prefecture in Japan was analyzed, and the future directions of measures against infectious diseases in public health centers was studied.
Method An outbreak of adult measles (in individuals more than 18 years old) occurred in the eastern part of Ehime prefecture between October 2002 and July 2003. During this outbreak, provisional surveillance of adult measles as well as pediatric measles (less than 18 years old) was performed by all clinics and hospitals in addition to that by The Ehime Epidemiological Surveillance of Infectious Diseases (sentinel surveillance). Furthermore, identification of viral genes was performed from pediatric and adult measles patient samples.
Results 112 cases of measles in adults and 200 cases in children were reported in Ehime between October 2002 and July 2003, and the rates for the eastern part of the prefecture accounted for 89.7% and 94.1% respectively. The relation between the pediatric measles and adult measles could be followed by change in the outbreak number of patients week by week. The genotype of the measles viruses isolated was type H1, which is prevalent in China and Korea. The results of an epidemiological survey showed that 59.3% of adult and 84.1% of pediatric cases had not been vaccinated. The measles vaccination rates for adult and pediatric cases were 21.9% and 11.4%, respectively. While the number of measles cases detected by sentinel pediatric surveillance comprised 32.0% of the measles cases reported by all pediatricians, the figure for adult measles cases was only 11.6% of those reported by all clinics and hospitals.
Conclusions It was suggested that improvement in the vaccination rates and revaccination rates mainly among school children or young people is necessary to prevent measles outbreaks. The surveillance system must be strengthened to increase the number of sentinel hospitals because an outbreak may not be detected with the current approach, especially for measles among adults. Positive information exchange between public health centers and medical institutions also appear to be particularly important.

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