To estimate an accurate annual incidence of Parkinson disease in Wakayama, a mail survey was conducted in 1998. A questionnaire was delivered to each clinic where Parkinson disease would be potentially diagnosed. The survey was conducted in February 1998 by the Research Committee on Parkinson disease of Wakayama. A total of 792 clinics and 87 hospitals were listed as candidates. Physicians in these 879 medical facilities were asked and instructed to register all newly diagnosed patients with Parkinson disease in 1997 according to the diagnostic criteria proposed by the Japanese Research Committee on Neuro-degenerative Diseases. Of 879 facilities, 873 ones including 81 hospitals replied (response rate: 99%). A total of 229 patients were reported as newly diagnosed cases in 1997. Of these cases, 183 cases were classified as Yahr I to III. The annual incidence rate was 16.9 per 100, 000 population (95% confidence interval: 14.5-19.3). Male-to-female ratio was 1:1.4 as a whole, and the dominant age stratum was 70 to 79 years old. When Parkinson disease incidence was observed from northern part of Wakayama to south by district, crude rates (95% Cls) were 15.9(12.9- 18.9), 18.1(12.0-24.2), and 19.3(13.4-25.2). After age-adjustment using the Japanese Model Population in 1985, differences of Parkinson disease incidence became attenuated and adjusted rates (95% Cls) turned to 10.8(9.1-12.7), 10.4(8.6-12.2), and 9.9(6.9-12.9), respectively. J Epidemiol 2002;12:403-407.
We have been conducting a cohort study titled the Jichi Medical School Cohort Study (The JMS Cohort Study) since 1992, which is aiming to clarify the risk factors of cardiovascular and cerebrovascular diseases in the Japanese. The baseline data were gathered from April 1992 through July 1995 in 12 rural districts using a legal mass screening system. The total samples were 12, 490 males and females, and the overall response rate for the total population was 63%. The mean ages were 55.2 years for males and 55.3 years for females, respectively. Smoking rates were 50.5% and 5.5%, and drinking rates were 75.1% and 25.0% for males and females, respectively. We also examined the Standardized mortality ratios (SMRs) of the cohort subjects for 7.6 year follow-up period. The SMRs were 0.68 [95% confidence interval (CI): 0.59-0.78] for males and 0.73 (95% CI: 0.62-0.85) for females for the cohort subjects, whereas the SMRs were 1.00 (95% Cl 0.97-1.04) for males and 1.06 (95% Cl: 1.02-1.10) for females for all residents. In this article, we outlined the cohort study and showed general characteristics of the baseline data, and the SMRs of the subjects. We have been following the eligible subjects, and are preparing to show some prospective data regarding cardiovascular and cerebrovascular risks in the near future. J Epidemiol 2002; 12:408-417.
A relationship between distance from major roads and the prevalence of allergic disorders and general symptoms among junior high school students was assessed, separating the effects of distance of residence and school from the roads. Study subjects were 5, 652 students aged 12 to 15 years. This study used diagnostic criteria from the International Study of Asthma and Allergies in Childhood. The questionnaire also asked about symptoms of headache, stomachache, tiredness, and cough and the shortest distance from residence to major roads. Distance from school to the nearest major road was measured on a map. Adjustment was made for gender, grade, the number of older siblings, smoking in the household, and maternal history of allergy. A shorter distance between residence and major roads was associated with an increased prevalence of headache, stomachache, tiredness, and cough. There was a marginally significant positive association between residence facing major roads and the prevalence of allergic rhinoconjunctivitis. Residence within 100 m of major roads showed a tendency for a positive relationship with the prevalence of wheeze and atopic dermatitis. There was no apparent relationship between distance of school from major roads and allergic disorders or the general symptoms. The findings suggest that proximity of residence, not school, to major roads may be associated with an increased prevalence of allergic disorders, headache, stomachache, and tiredness among Japanese adolescents. Further investigations with more precise and detailed exposure and health outcome measurements are needed to corroborate the relationship between traffic related factors and allergic disorders and general symptoms. J Epidemiol 2002; 12:418-423.
The aim of this case-control study was to evaluate the association between the lifestyle risk factors, especially physical activity, and the prevalence of type 2 diabetes and the comorbidity of type 2 diabetes and dyslipidemia in middle-aged Japanese urban population. Subjects (279 males and 119 females, 53.5±6.8 years old) were selected from one city office in Tokyo and consisted of type 2 diabetes cases (n=53), dyslipidemia cases (n=130), the comorbidity cases (n=58) and sex- and agematched controls (n=155). A self-administered questionnaire was used to collect physical activity data using Baecke's questionnaire translated and other lifestyle data. Our results revealed that physical activity was significantly associated with the reduction of the prevalence of type 2 diabetes and the comorbidity, and the sex- and age-adjusted odds ratios of the fourth quartile to the lowest one were 0.31(95%Cl:0. 12-0.81) and 0.32 (95%Cl:0.13-0.81), respectively. Family history of diabetes and smoking were independent risk factors for the prevalence of type 2 diabetes and the comorbidity. J Epidemiol 2002;12:424-430.
We examined the association of nutritional factors with body fat deposition in a representative sample (n=530, aged 40-79 years) of first and second-generation Japanese-Brazilian population who was submitted to standardized questionnaires, including nutritional data, clinical examination and laboratory procedures. Dietary data were compared between groups of subjects defined by the presence of obesity or central adiposity. Associations of body mass index or waist circumference (dependent variables) with energy and nutrient intakes (main exposure of interest) were analyzed by multiple linear regression, with adjustment for gender, age, physical activity and generation. Groups of obese subjects and those with central adiposity consumed higher proportions of energy as fat and lower as carbohydrate than those without obesity and central adiposity (p<0.05). Stratifying by generation, second-generation was shown to take more energy as fat than the first-generation (p<0.05). In the regression models, pro- tein intake was the only variable significantly associated with body mass index. Replacing body mass index by the waist circumference, male sex and protein intake were shown to be independent predictors of central adiposity. When second-generation was taken, total energy intake and all macronutrient intakes became significantly associated with body mass index (p<0.05) but only protein intake predicted waist circumference. We speculate that Japanese-Brazilians, genetically prone to insulin resistance, when exposed to unfavorable environment will express a number of metabolic disturbances. A deleterious dietary pattern may contribute to weight gain, was associated with abdominal fat deposition in particular a protein-rich diet, and reflected by their waist circumference. Intra-abdominal fat could be triggering insulin resistance, which would explain the increased prevalence rates of diabetes, dyslipidemia and hypertension seen in Japanese-Brazilians. J Epidemiol 2002; 12:431-438.
Suicide rate in Japan surged in 1998. Although the standardized mortality ratios (SMRs) of suicide in Osaka Prefecture, Japan had been mostly lower than the national SMRs of suicide between 1980 and 1997, they surpassed the increased national SMR of suicide in 1998 and 1999. We investigated whether the suicide rates for 1980-97 and the recent increased suicide rates in Osaka Prefecture were associated with socioeconomic factors. Time-series regression analyses of the suicide rate and socioeconomic factors were performed on respective data for five sub-areas in Osaka Prefecture. The suicide rates of young people and middle-aged men were more strongly associated with the job application and divorce rates for 1980-99 than for 1980-97. Some relations between the suicide rate and public assistance rate were found. The suicide rate was negatively associated with the marriage rate in some areas. The suicide rate of elderly women was strongly associated with the number of persons per household. The notable relation was found between the suicide rate of middle-aged men and the job application rate for 1980-99. The inverse relation between the suicide rate of elderly women and the number of persons per household was noteworthy. J Epidemiol2002;12:439-449.
This study aims to evaluate the contribution of the change in circulatory diseases mortality to the life expectancy at birth observed during the years 1955-1995 in Japan. We used data on the population and the number of deaths by cause, age, and sex in 1955, 1965, 1975, 1985, and 1995. The contribution of different ages and causes of death to the change in life expectancy were examined with the method developed by Pollard. We found that the reduction in circulatory diseases mortality contributed to the improvements in life expectancy for both sexes during the decade 1975-1985. Much of this was due to the decrease in cerebrovascular disease. In the years 1985-1995, however, the contribution of cerebrovascular disease decreased in both sexes, while that of heart disease grew to become the largest of any single condition. By age, the contribution of all circulatory diseases increased among the elderly in recent years. The contribution of the change in circulatory diseases mortality to the life expectancy at birth has increased in recent years but seems to have reached a plateau. The weight against improvements in life expectancy in middle-aged people has shown little change, so that reducing the mortality rate in middle-aged people is now a major issue. J Epidemiol2002;12;450-456.