Sleep duration and incidence of cardiovascular events in a Japanese population: the Jichi Medical School cohort study.

BACKGROUND: Although sleep is one of the most important health-related factors, the relationship between sleep duration and the incidence of cardiovascular events has not been fully described. METHODS: The present study comprised the 11,367 study subjects (4413 men and 6954 women) of the Jichi Medical School Cohort Study, a population-based prospective study. Baseline data were obtained by questionnaire and health examinations between April 1992 and July 1995 in 12 rural areas in Japan, and the main outcome measures were the incidence of cardiovascular diseases (stroke and myocardial infarction [MI]). Cox proportional hazards models were used to analyze the association between sleep duration and the incidence of cardiovascular events. RESULTS: A total of 481carciovascular events (255 men and 226 women) were observed during an average follow-up period of 10.7 years. After adjusting for age, systolic blood pressure, serum total cholesterol, body mass index, smoking habits, and alcohol drinking habits, the hazard ratios (95% confidence intervals) for the incidence of cardiovascular diseases for individuals sleeping less than 6 hours and 9 hours or longer were 2.14 (1.11-4.13) and 1.33 (0.93-1.92) in men, and 1.46 (0.70-3.04) and 1.28 (0.88-1.87) in women, respectively, relative to those who reported sleeping 7 to 7.9 hours per day. CONCLUSIONS: Our data indicate that men who sleep less than 6 hours a day have a higher risk of cardiovascular events than those sleeping 7 to 7.9 hours.

[Home care service at the division of general medicine in Jichi Medical University Hospital--the terminal stage cancer patient's care in the past 3 years].

We have provided a home care service for the past 20 years as a part of our community medical program at the Division of General Medicine in Jichi Medical University Hospital (JMUH). We reflected our activities of the past 3 years since 2004, and considered our meanings of home care service at the University Hospital. Especially, we reported on terminal stage cancer patients who died in the past 3 years. We normally visit about 10 homes of our patients who live near the University Hospital. There has been a decreasing trend toward a regular home visit by doctor, but an emergency visit has been increasing. Further more, we visited many elderly cerebral vascular patients in the past. However, many terminal stage cancer patients have now been requesting us to visit their homes. A total of 17 patients died in the past 3 years: 10 of 17 patients died at their homes, and 6 of them were terminal stage cancer patients who died at their homes.

Age at menopause and mortality in Japan: the Jichi Medical School Cohort Study.

BACKGROUND: Although several studies have reported increased mortality risk with early menopause, there were no studies examining the relationship between age at menopause and mortality in Japan. The goal of this analysis is to investigate the relationship between age at menopause and all-cause mortality among the Japanese. METHODS: Study subjects were 4,683 postmenopausal females in the Jichi Medical School Cohort Study, a population-based prospective study. Baseline data were obtained by questionnaire and health checkups between April 1992 and July 1995 in 12 rural areas in Japan. Main outcome measures were all-cause mortality derived from death certificates up to December 31, 2002. Cox's proportional hazard models were used to analyze the association of age at menopause with mortality. RESULTS: A total of 215 deaths were observed during the average of 9.2 year follow-up period. After adjusting for age, systolic blood pressure, serum total cholesterol level, serum high density lipoprotein cholesterol level, history of diabetes mellitus, body mass index, smoking habits, alcohol drinking habits, marital status, study area, and types of menopause, the hazard ratios (95% confidence intervals) of all-cause mortality were 2.10 (1.07-4.11), 0.68 (0.36-1.26), 0.94 (0.68-1.30), and 1.17 (0.63-2.20) for females with a menopause at ages younger than 40 years, 40-44, 50-54, and 55 or older, respectively, relative to those with menopause at age 45-49 years. CONCLUSIONS: Our data suggest that menopause aged younger than 40 years increases the risk of death from all causes among the Japanese.

Sleep duration and mortality in Japan: the Jichi Medical School Cohort Study.

BACKGROUND: Although sleep is one of the most important health-related factors, relationship between sleep duration and mortality has not been fully discussed. METHODS: Study subjects were 11,325 participants (4,419 males and 6,906 females) in the Jichi Medical School Cohort Study, a population-based prospective study. Baseline data were obtained by questionnaire and health checkups between April 1992 and July 1995 in 12 rural areas in Japan. Main outcome measures were all-cause and cause-specific mortality derived from death certificates up to December 31, 2001. Cox's proportional hazard models were applied to analyze the association of sleep duration with mortality. RESULTS: A total of 495 deaths (289 males and 206 females) were observed during the average of 8.2-year follow-up period. After adjusting for age, systolic blood pressure, serum total cholesterol, body mass index, smoking habits, alcohol drinking habits, education, and marital status, the hazard ratios (95% confidence intervals) of all-cause mortality for individuals sleeping shorter than 6 hours and 9 hours or longer were 2.4 (1.3-4.2) and 1.1 (0.8-1.6) in males, and 0.7 (0.2-2.3) and 1.5 (1.0-2.4) in females, respectively, relative to those with 7-7.9 hours sleep. CONCLUSION: Our data suggest that males with short sleep and females with long sleep were at an elevated risk of death.