Temporal course of the development of obesity in Japanese school children: a cohort study based on the Keio Study.

OBJECTIVE: To demonstrate the temporal course of obesity development in Japanese school children by conducting a school-site cohort study over 12 years. METHODS: From 1981 to 1984, height and weight of 479 subjects (343 boys and 136 girls) were measured every year from entrance into primary school until graduation from high school in Tokyo. Obese children were defined as those with a body mass index (BMI) at or above the age-sex-specific standard value, derived from Japanese nationwide data. RESULTS: Approximately 50% of the children who were obese in the primary school period were obese at age 17. Likewise, 40% who were obese in the junior high school period and 70% who were obese in the high school period were obese at age 17. Among 44 children who were obese at age 17, 14 showed tracking of obesity from the preschool period, 14 showed tracking from ages 7 to 11 years, 10 showed tracking from the junior high school period, and 6 showed tracking from the high school period. CONCLUSIONS: Among children who were obese at age 17, most tracked from the primary school age or earlier. The earlier the tracking commenced, the greater the BMI at age 17. This indicates the importance of conducting health education for school children at an early age.

Hepatitis B virus markers in Japanese immigrants and their descendants in Bolivia and native Bolivians.

A survey of hepatitis B virus (HBV) markers of Japanese immigrants, their descendants and native Bolivians was performed in two agricultural settlements in Bolivia. The prevalence of HBV markers in sera, either hepatitis B surface antigen (HBsAg) or its antibody (HBsAb), was higher in the Japanese (46.4%) than in the native Bolivian (12.9%) adult generations of both colonies. There was no significant difference between Japanese (4.3%) and Bolivian (0.9%) school children in one colony, but a high percentage (32.6%) was recognized among Japanese children in the other colony. The numbers of adw subtypes were unexpectedly high among these HBsAg positive Japanese children, compared to those in Japan. Antibody to hepatitis delta virus (HDV) was detected in one case. These data suggested that although horizontal transmission of adw HBV had occurred within the Japanese population, HBV and HDV were not endemic to this geographic area.

Infectious states of human T lymphotropic virus type I and hepatitis B virus among Japanese immigrants in the Republic of Bolivia.

Serologic tests for human T lymphotropic virus type I (HTLV-I) and hepatitis B virus infections were conducted in 1986 in two Japanese immigrant colonies located in Santa Cruz, Bolivia. A total of 322 adults (283 Japanese and 39 Bolivians) over age 35 years and 305 children (166 Japanese, 124 Bolivians, and 15 of mixed blood) aged 8-17 years were sampled at the time of a routine health checkup. The prevalence of antibody to HTLV-I was 17% in first-generation Japanese immigrants and 6% in second- or third-generation Japanese children. Prevalences among native Bolivians were 3% and 5% in adults and children, respectively. Seropositive Japanese immigrants and mothers showed clustering according to birthplace in endemic areas of Japan. The prevalence of either hepatitis B virus surface antigen (HBsAg) or antibody to HBsAg was 48% in Japanese adults, 21% in Japanese children, 13% in Bolivian adults, and 1% in Bolivian children. Seropositive adults did not show clustering according to birthplace, but children in one colony showed clustering and a narrow age range. A correlation of seropositivity between husbands and wives was found only for HTLV-I. The seropositivity was independent of whether an HTLV-I or a hepatitis B virus infection marker was present.

Prevalence of antibodies to human T-cell leukemia/lymphoma virus type I and human immunodeficiency virus in Japanese immigrant colonies in Bolivia and Bolivian natives.

This study was performed to estimate human T-cell leukemia-lymphoma virus type-I (HTLV-I) infection and human immunodeficiency virus (HIV) infection in Japanese immigrant colonies in Bolivia, where no seroepidemiological study of HTLV-I or HIV has ever been reported, among 647 healthy adults and children of Japanese descent and Bolivian natives living in the same colonies. The overall prevalence of HTLV-I antibody was 12.6% (59/469) among Japanese immigrant populations, but increased with age, being 16.2% (49/303) among adults and 6.0% (10/166) among children; no significant difference in relation to sex was noted. The first generation immigrants (issei) from Kyushu, the large southwestern island of Japan where adult T-cell leukemia (ATL) is endemic, had 19.0% (49/258) HTLV-I seroprevalence, while issei from outside Kyushu had none (0/39). Among Bolivian members of the community, consisting mostly of Indians and persons of Spanish descent, the HTLV-I seroprevalence was 4.3% (7/164) overall, 2.4% (1/42) among adults and 4.9% (6/122) among children. No antibody to HIV was detected among Japanese or Bolivian populations. The results of this study show that: (1) there is a considerable number of HTLV-I carriers among Japanese immigrant populations in Bolivia, especially among immigrants from Kyushu, (2) there exist some HTLV-I carriers among Bolivian natives, raising the possibility of HTLV-I transmission by co-habitation with Japanese immigrants, (3) HIV is far from endemic in this district of Bolivia, at present.

PIP: This study was performed to estimate human T-cell leukemia-lymphoma virus type-I (HTLV-I) infection and human immunodeficiency virus )HIV) infection in Japanese immigrant colonies in Bolivia, where no seroepidemiological study of HTLV-I or HIV has ever been reported, among 847 healthy adults and children of Japanese descent and Bolivian natives living in the same colonies. The overall prevalence of HTLV-I antibody was 12.6% (59/469) among Japanese immigrant populations, but increased with age, being 16.2% (49/303) among adults and 6.0% (10/166) among children; no significant difference in relation to sex was noted. The 1st generation immigrants (issei) from Kyushu, the large southwestern island of Japan where adult T-cell leukemia (ATL) is endemic, had 19.0% (49/258) HTLV-I seroprevalence, while issei from outside Kyushu had none (0/39). Among Bolivian members of the community, consisting mostly of Indians and persons of Spanish descent, the HTLV-I seroprevalence was 4.3% (7/164) overall, 2.4% (91/42) among adults, and 4.9% (6/122) among children. No antibody to HIV was detected among Japanese or Bolivian populations. The results of this study show that: there is a considerable number of HTLV-I carriers among Japanese immigrants in Bolivia, especially among immigrants from Kyushu, there exist some HTLV- I carriers among Bolivian natives, raising the possibility of HTLV-I transmission by cohabitation with Japanese immigrants, and HIV is far from endemic in this district of Bolivia at the present time.