Childhood mortality due to unintentional injuries in Japan, 2000–2009.

This study examined deaths due to unintentional injuries among children in Japan to identify the age groups and sexes at most risk, and the types of injuries, so that effective forms of targeted intervention can be devised. Among children aged 0-14 years, deaths whose underlying causes had been classified under code V01-X59 of the ICD-10 were defined as deaths of children caused by unintentional injuries. Using data from the Vital Statistics 2000-2009 for analysis, we examined the changes in mortality and trends in terms of sex, age, and cause of death. Mortality decreased by 46.2%, from 933 in 2000 to 502 in 2009. The mortality rate among children aged 1-4 years decreased by almost half. The total number of deaths during this decade was 7,362 (boys: 4,690, girls: 2,672). Among the causes of death, the majority were due to "transport accidents", followed by "other accidental threats to breathing", and "accidental drowning and submersion". The characteristics observed in terms of sex, age, and cause of death--that is, deaths from suffocation among infants aged less than 1 year, drowning deaths among boys, and transport accidents involving pedestrians and cyclists--must be addressed as targets for future intervention.

Blue Monday phenomenon among men: suicide deaths in Japan.

The number of suicide deaths in Japan has continued to be high, and is a pressing social problem. Although the weekly distribution of suicide deaths has been documented, no nationwide analysis has yet been conducted. In the present study, the ratios of the number of suicide deaths per day, by day of the week, and on weekdays relative to holidays were calculated using the data for all suicide deaths recorded in 2003. The suicide deaths recorded on holidays were treated as the reference, and a confidence interval of 95% (95% CI) was used. We calculated the suicide death ratios among men and women of all ages (men:23,396, women:8,713, total:32,109) and also among those of productive age (age:15-64 years, men:18,552, women:5,481, total:24,033). Among men of all ages, the suicide death ratio on Mondays was found to be significantly high at 1.49 (95% CI:1.04-2.14), and the ratios were found to decrease over the course of the week from Monday to Friday. On each weekday, the suicide death ratios among men of productive age were found to be higher than those among men of all ages. Among women, the suicide death ratios on any weekday were found to be higher than 1, but there was no significant difference between the days. Among both men and women, the number of suicide deaths on holidays was lower than that on weekdays. This study revealed that the number of suicide deaths recorded per day on Mondays is 1.5 times higher than that on holidays among men. This suggests that the structure of the work week may possibly influence suicide deaths among men. Future discussions regarding the arrangement and distribution of weekly holidays should be conducted in order to reduce the number of suicide deaths.

NADH dehydrogenase subunit-2 237 Leu/Met polymorphism modulates the effects of coffee consumption on the risk of hypertension in middle-aged Japanese men.

BACKGROUND: Habitual coffee consumption has been reported to lower blood pressure in the Japanese population. The NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism is associated with longevity and modifies the effects of alcohol consumption on blood pressure in the Japanese population. The objective of this study was to determine whether this polymorphism also modifies the effects of coffee consumption on blood pressure or the risk of hypertension in middle-aged Japanese men. METHODS: A total of 398 men (mean age +/- standard deviation, 53.8 +/- 7.8 years) were selected from among individuals visiting the hospital for regular medical check-ups. Hypertension was defined as a systolic blood pressure > or =140 mm Hg, diastolic blood pressure > or =90 mm Hg, or antihypertensive drug treatment. Polymerase chain reaction-restriction fragment length polymorphism using the restriction enzyme AluI was performed to determine ND2-237 Leu/Met genotype. RESULTS: In subjects with ND2-237Leu, coffee consumption was significantly and negatively associated with diastolic blood pressure (P = 0.007). The odds ratio (OR) for hypertension was significantly lower in subjects with ND2-237Leu who consumed 2 or 3 cups of coffee per day than in those who consumed less than 1 cup of coffee per day (OR, 0.517; 95% confidence interval [CI], 0.276 to 0.968; P = 0.039). After adjustment, the OR remained significant (OR = 0.399; 95% CI, 0.184 to 0.869; P = 0.020). Moreover, after adjustment, the OR was significantly lower in subjects with ND2-237Leu who consumed more than 4 cups of coffee per day than in those who consumed less than 1 cup of coffee per day (OR, 0.246; 95% CI, 0.062 to 0.975; P = 0.046). However, the association between ND2-237Met genotype and hypertension did not depend on coffee consumption. CONCLUSIONS: The present results suggest that the ND2-237 Leu/Met polymorphism modulates the effects of coffee consumption on hypertension risk in middle-aged Japanese men.

Human intake of PCDDs, PCDFs, and dioxin like PCBs in Japan, 2001 and 2002.

PCDDs, PCDFs, and dioxin like PCBs (dioxin) surveillance results derived from regular environmental monitoring as well as other dioxin surveys by national and local governmental bodies in Japan were collected and analyzed. Several thousand data for air and soil in fiscal year 2001 (from 01/04/2001 to 31/03/2002) and 2002, water (from the sea, rivers and lakes), sediment (from the sea, rivers and lakes), ground water, aquatic organisms, purified water from water purification plants, raw water from water purification plants, human breast milk, and human blood in fiscal 2001, and total diet study (TDS) and various kinds of foodstuff in fiscal 1998-2002 were collected. Average human uptake of dioxin in Japan in fiscal 2001 was estimated at 1.68 pg-TEQ/kg-bw/day, while uptake in fiscal 2002 was estimated at 1.52 pg-TEQ/kg-bw/day. Diet accounted for more than 90% of the total intake. Contributions of inhalation and soil ingestion were relatively small. Age-group-specific contribution of various foodstuff to total dietary intake was also estimated. The estimates of intake through fish and shellfish accounted for approximately 45-70% of total dietary intake in each age group. Monte Carlo simulation was conducted, using the data of the air and soil concentrations in fiscal 2001 and the total diet study data in fiscal 1998-2001, in order to obtain information on the variability of dioxin intake; The estimated average, median, 5th percentile and 95th percentile of the intake distribution were 1.78, 1.69, 0.95 and 2.91 pg-TEQ/kg-bw/day, respectively. This study found that the average total intake estimates in Japan in both fiscal 2001 and 2002 were estimated to be below tolerable daily intake level (TDI) defined by the Ministry of Health, Labour and Welfare, Japan (i.e. 4 pg-TEQ/kg-bw/day). The 95th percentile of the dioxin intake distributions estimated with Monte Carlo simulation using the data of the air and soil concentrations in fiscal 2001 and TDS data in fiscal 1998-2001 was also below the Japanese TDI.