The relationships between Dehydroepiandrosterone sulfate (DHEAS) level and atherosclerosis were studied using 90 men who received a general medical examination in their company. The mean serum DHEAS level was 1510.2ng/ml, while the frequency distribution was skewed to a lower value. A marked linear decline of levels with age was observed. DHEAS levels were positively correlated with high density lipoprotein-choresterol (HDLC) (r=0.22, p<0.05), and negatively correlated with low density lipoprotein-choresterol (LDLC) (r=-0.31, p<0.001), even after adjustment for age. The mean Atherogenic Index (AI) was significant inversely correlated with rise of tertiles of the DHEAS level, both before and after adjustment for age, total cholesterol (TC), HDLC and triglyceride (TG). These results suggest that DHEAS may have an important role in the etiology and prevention of atherosclerosis. J Epidemiol, 1996; 6 : 63-67.
A case control study was carried out in order to evaluate the various factors which may influence the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) infections in a skilled nursing home. From April 1991 to March 1994, bacterial cultures were performed in 55 out of 102 residents in a nursing home based on various clinical aspects. We divided 102 residents into following three groups ; (1) the MRSA group (n=1 0), residents whose materials for bacterial culture were positive for MRSA, (2) the non-MRSA group (n=45), residents whose specimens were negative for MRSA but positive for other bacteria, (3) the control group (n=47), residents who did not have to undergo a bacterial culture because they were free from moderate and severe infectious diseases. Compared with the control group, the activities of daily living score and the serum albumin level were significantly lower in the MRSA group and the non- MRSA group at the beginning of the study. In contrast, the number of antibiotics used prior to the bacterial culture and the proportion of hospitalization within 6 months prior to the bacterial culture were significantly larger in the MRSA group than in either the non-MRSA group, or the control group. These results thus suggest that a low activities of daily living score, the use of many kinds of antibiotics and a recent previous hospitalization may be risk factors of MRSA infection in a nursing home environment. J Epidemiol, 1996; 6 : 69-73.
In order to clarify the epidemiological features of chronic fatigue syndrome (CFS), a nationwide survey was conducted using the Japanese version of the CDC Criteria prepared by the CFS Research Group of Japan. All clinical departments of internal medicine, pediatrics, psychiatry and neurology at university hospitals and at ordinary hospitals with 200 or more beds were surveyed. Major results were as follows : (1) Period prevalence adjusted for response rate was 0.85 (0.63 for males and 1.02 for females) per 100, 000 population during the year 1992 ; (2) Based on the first and final dates of hospital visits, the prevalences on January 1 of 1992 and 1993 were 0.40 and 0.60 per 100, 000 population, respectively, suggesting an increasing trend ; (3) Reported new cases during 1992 were 301, and the response adjusted-incidence was estimated to be 0.46 per 100, 000 person-years ; (4) The proportion of post-infectious CFS cases was 14.8% for both sexes, and tended to be slightly higher among females than males, but was not related to age. Three clusterings of two cases were reported. J Epidemiol, 1996; 6:75- 80.
To examine contribution of plasma fibrinogen concentrations to coronary atherosclerosis in Japanese, a cross-sectional study was conducted from 1991 to 1993 for 169 myocardial infarction cases and 1 : 1 matched references. All cases had one to three coronary vessels with 50 percent or more stenosis. References were chosen out of Osaka residents who had no cardiac event by matching sex and age (+- 3 years) with cases. Mean (SD) values of plasma fibrinogen concentration were 322 (81) mg/dl in men and 377 (77) mg/dl in women for cases, and were 282 (56) mg/dl in men and 277 (48) mg/dl in women for references ; mean plasma fibrinogen was significantly higher in cases than in references for both men and women. Furthermore, mean plasma fibrinogen was progressively higher as the number of stenotic vessels increased for men, and similar trend was seen for women. The case-reference difference remained significant even after adjusting smoking status, hypertension, serum total cholesterol, serum HDL cholesterol. Although plasma fibrinogen concentration was reported lower in Japanese than in American Caucasians, plasma fibrinogen is suggested to be a risk factor for myocardial infarction among Japanese as so among Caucasians. J Epidemiol, 1996; 6 : 81-86.
Relationships between smoking habits and other behavior factors such as habitual exercise, physical activities, and alcohol drinking habits were observed among Japanese males. Data used were obtained in The 1990 National Cardiovascular Survey in Japan, which consisted of 3826 males aged 30+ years selected from the Japanese population randomly. The proportion of current smokers was 53.5% in overall, and it decreased according to aging; these results were similar to Japanese former data. Those exercising habitually were more likely to be former smokers, whereas no relationship was observed between smoking habits and physical activities. Smoking and alcohol drinking habits were closely related; habitual drinkers were 3.34 times as likely to be current smokers as non-drinkers. Dose-response relationship was observed as well. Thus, the relationship between smoking and alcohol drinking habits was shown quantitatively. J Epidemiol, 1996 ; 6 : 87-91.
Trends of cardiovascular disease risk factors were evaluated through comparison of three national surveys in Japan, 1971-1990. Data from three Japanese national surveys on circulatory disorders, conducted in 1971, 1980, and 1990, were analyzed. Variables common to the three national surveys were selected for analysis. Serum total cholesterol was also but was examined only in 1980 and 1990. Age- and sex-specific mean values, standard deviations, median values, and proportions in extreme categories were determined for all continuous variables and proportions in categories interest for all discrete variables. Trends from 1971-1990 and 1980- 1990 were estimated by linear regression analysis for continuous variables, and logistic regression analysis for binary variables. Systolic blood pressure was decreasing constantly during three surveys in both men and women (β=-0.22 in men and -0.34 in women, p<0.01 in both). Total cholesterol was increasing rapidly in both men and women between 1980 and 1990 (β=1.27 in men and 1.41 in women, p<0.01 in both). For other risk factors, the results were less consistent among age- or sex-specific groups. Continued monitoring of risk factor trends in Japan will be important for predicting and explaining future trends in the occurrence of coronary heart disease and stroke in this population. J Epidemiol, 1996 ; 6 : 93-107.
The aim of the present study is to determine the reference value of erythrocyte sedimentation rate for differential diagnosis of rheumatic fever in the National Center for Control of Rheumatic Fever and Heart Diseases, Dhaka, Bangladesh among patients with signs and symptoms which may be related to acute rheumatic fever. All medical records for the patients aged 5 to 20 years who attended the outpatient department of the hospital between July, 1994 and November, 1995 were reviewed. Fifty-three of 337 such patients had acute rheumatic fever defined by the updated Jones criteria. The performance of erythrocyte sedimentation rate test was evaluated by sensitivity, specificity, positive predictive value, and receiver operating characteristic curve. The findings of this study suggest that the lower limit for a positive test should be considered at 30 mm (Westergren 1 h) in this hospital. J Epidemiol, 1996 ; 6 : 109-113.