Choy-Lye Chei

Body Fat Distribution and the Risk of Hypertension and Diabetes among Japanese Men and Women

To identify anthropometrical indices of body fat distribution for predicting the risk of hypertension and diabetes, a population-based prospective study was designed. Subjects in two communities (n=2,422 and 3,195), who were free of hypertension and diabetes, respectively, were followed-up. The area and gender-specific risk of hypertension and diabetes were compared among tertiles of body mass index (BMI) and body fat distribution, including waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), and subscapular skinfold-thickness (SSF). During the 10-year follow-up for hypertension and diabetes, the incident cases of hypertension were 72 for Yao men, 125 for Kyowa men, 160 for Yao women and 193 for Kyowa women and those of diabetes were 27, 64, 37 and 77, respectively. One SD differences in BMI and WC were associated with 1.2 to1.6-fold higher risk of hypertension, and that of SSF was associated with 1.4 to 1.6-fold higher risk of diabetes for both men and women in Yao and for women, but not men, in Kyowa. One SD differences of BMI, WC and WHtR were also associated with 1.4 to 2.0-fold higher risk of diabetes for Yao and Kyowa women. In conclusion, the significant predictors for hypertension were BMI and WC and those for diabetes were BMI and SSF in both genders in both communities, except for men in Kyowa. WC and WHtR were also predictors for diabetes in women but not in men.

Metabolic Syndrome and the Risk of Ischemic Heart Disease and Stroke among Middle-Aged Japanese

Limited information is available regarding risk of cardiovascular disease and trends for the metabolic syndrome in Asia. We examined the impact of the metabolic syndrome and its components on risk of cardiovascular disease among middle-aged Japanese according to four criteria. We followed 2,613 subjects from a rural Japanese community who participated in cardiovascular health examinations between 1990 and 1993. After 27,477 person-years of follow-up through 2003, there were 42 incidents of ischemic heart disease, 73 total strokes (54 ischemic and 18 hemorrhagic), and 115 total cases of cardiovascular disease. The metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII), American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI), International Diabetes Federation (IDF), and Japanese criteria. The multivariable hazard ratios (95%CI) associated with the metabolic syndrome based on NCEP-ATPIII criteria were 2.1 (1.1–4.0) for ischemic heart disease, 1.7 (1.0–2.7) for total stroke, 2.0 (1.2–3.5) for ischemic stroke, 1.1 (0.4–2.8) for hemorrhagic stroke, 2.0 (1.3–3.1) for ischemic cardiovascular disease, and 1.7 (1.2–2.5) for total cardiovascular disease. The population- attributable fractions of the metabolic syndrome based on NCEP-ATPIII criteria were 26–27% for ischemic heart disease and ischemic stroke and 20% for total cardiovascular disease. The metabolic syndrome based on AHA/NHLBI, IDF and Japanese criteria had weaker associations with risk of cardiovascular disease, and the association with risk of ischemic heart disease was not statistically significant. The metabolic syndrome based on NCEP-ATP III criteria predicted risks of ischemic heart disease, ischemic stroke and total cardiovascular disease, whereas that based on three other criteria predicted them less effectively.

C-reactive protein levels and risk of stroke and its subtype in Japanese: The Circulatory Risk in Communities Study (CIRCS)

BACKGROUND Epidemiological studies have shown high-sensitive C-reactive protein (hs-CRP) to predict cardiovascular disease. However, there are only limited studies on the effects of hs-CRP levels on risk of stroke especially stroke subtypes. We examined associations of hs-CRP levels with risks of total stroke and its subtypes. METHODS A prospective nested case-control study of Japanese 40-85 years of age was conducted using frozen serum samples collected from 13,521 men and women who participated in cardiovascular risk surveys from 1984 to 2001 for one community and 1989 to 1998 for the other two communities under the Circulatory Risk in Communities Study (CIRCS). Three control subjects per case were matched by sex, age, community, year of serum storage, and fasting status. RESULTS By the end of 2005, we identified 261 incident strokes (165 ischemic strokes and 96 hemorrhagic strokes). There was a positive association between hs-CRP and incidence of incidence of total stroke, ischemic stroke and lacunar infarction. After further adjustment for known cardiovascular risk factors, these relationships remained statistically significant. The multivariable conditional odds ratios associated with 1-SD increment of log-transformed hs-CRP were 1.17(1.01-1.35) for total stroke, 1.27(1.06-1.52) for ischemic stroke, and 1.24(1.00-1.55) for lacunar infarction. The association between hs-CRP levels and incidence of ischemic stroke did not vary by sex, age, body mass index and smoking. No associations were found between hs-CRP levels and risk of hemorrhagic stroke. CONCLUSIONS hs-CRP predicts the incidence of total and ischemic strokes among middle-aged Japanese men and women.

Cigarette Smoking and Risk of Disabling Dementia in a Japanese Rural Community: A Nested Case-Control Study

Background: Previous prospective cohort studies have examined the association between smoking and the risk of dementia, but the results were inconsistent. Methods: A prospective, nested, case-control study was conducted to examine the association between cigarette smoking and risk of disabling dementia within the cohort of 6,343 men and women aged 35–85 years. Incident dementia was documented in 208 men and women (95 cases with and 113 cases without a history of stroke). Two control subjects per case were selected by matching for sex, age and year of examination. Results: The multivariable odds ratios (95% CI) for current versus never smokers were 2.3 (1.1–4.7) for total dementia, 2.6 (0.8–8.2) for dementia with a history of stroke and 2.2 (0.8–5.7) for dementia without it, yielding no effect of stroke history on the smoking-dementia association. A dose-response relationship was noted between the years of cigarette smoking and the risk of total dementia, and a significant excess risk was found for smoking duration of ≧45 years. Conclusions: The present prospective study suggests that long-term cigarette smoking may raise the risk of disabling dementia.

High-density Lipoprotein Subclasses and Risk of Stroke and its Subtypes in Japanese Population The Circulatory Risk in Communities Study

Background and Purpose— High-density lipoprotein (HDL) cholesterol is an established protective factor for ischemic stroke. However, the contribution of HDL subclasses to stroke risk and its subtypes is uncertain. Methods— A prospective nested case–control study of 40- to 85-year-old Japanese was undertaken using frozen serum samples collected from 5280 men and 7524 women. They participated in cardiovascular risk surveys from 1985 to 1999 (1 community) and 1989 to 1998 (2 communities) under Circulatory Risk in Communities Study. HDL cholesterol subclasses were classified by high-performance liquid chromatography into 3 subgroups: S-HDL (very small or small HDL), M-HDL (medium HDL), and L-HDL (large or very large HDL) cholesterol. One control subject per case was matched by sex, age, community, serum storage year, and fasting status. Results— In 2005, we identified 241 strokes (155 ischemic and 86 hemorrhagic). S-HDL and M-HDL cholesterol levels were inversely associated with total stroke risk, ischemic stroke, specifically lacunar infarction, and hemorrhagic stroke. After adjustment for cardiovascular risk factors, these associations remained statistically significant. Multivariable conditional odds ratios (95% confidence interval) for 1 SD (0.12 mmol/L) increment of S-HDL cholesterol levels were 0.34 (0.23–0.52) for total stroke, 0.38 (0.23–0.63) for ischemic stroke, 0.33 (0.18–0.61) for lacunar infarction, 0.30 (0.14–0.65) for hemorrhagic stroke, and 0.30 (0.12–0.77) for intraparenchymal hemorrhage. The respective multivariable odds ratios for 1SD (0.10 mmol/L) increment of M-HDL cholesterol levels were 0.56 (0.41–0.75), 0.63 (0.45–0.88), 0.59 (0.40–0.87), 0.41 (0.21–0.80), and 0.38 (0.16–0.90). No associations were found between L-HDL cholesterol levels and risk of total stroke and its subtypes. Conclusions— Small- to medium-sized HDL, not large HDL, cholesterol levels were inversely associated with total stroke risk.

Total and high molecular weight adiponectin levels and risk of cardiovascular disease in individuals with high blood glucose levels

OBJECTIVE The association of adiponectin levels with cardiovascular disease (CVD) may vary by age and health condition. It is unknown whether adiponectin predicts CVD events among individuals with high blood glucose levels. METHODS We conducted a nested case-control study among 15,566 men and women aged 40-85 years from four communities, who were free of CVD at baseline. During 192,181 person-years of follow-up, 117 individuals subsequently developed coronary heart disease or ischemic stroke and had high plasma glucose concentrations (fasting/nonfasting ≥ 5.6/7.2 mmol/L or treated) at baseline. Controls were randomly selected at a 2:1 ratio and matched for sex, age, blood glucose, year of survey, fasting conditions, and community (n = 234). Baseline total and high molecular weight (HMW) adiponectin and their ratio were examined for total subjects and the association with CVD was compared between ages of 40-69 and 70-85 years. RESULTS After adjustment for matched variables and traditional risk factors, total and HMW adiponectin and their ratio were not associated with overall risk of CVD. However, significant interactions of the associations between the age groups were found. The highest quartile for HMW adiponectin and HMW/total adiponectin ratio decreased risk of CVD compared with the lowest quartile among middle-aged individuals (multivariable-adjusted odds ratio = 0.33 [95%CI, 0.13-0.83] and 0.47 [0.22-0.98], respectively), while this association was not seen among the elderly. CONCLUSIONS High HMW adiponectin levels may decrease the risk of CVD in middle-aged adults with high blood glucose.

Prevalence and Risk Factors of Atrial Fibrillation in Chinese Elderly: Results from the Chinese Longitudinal Healthy Longevity Survey

Background: Prevalence of atrial fibrillation (AF) is increasing as the world ages. AF is associated with higher risk of mortality and disease, including stroke, hypertension, heart failure, and dementia. Prevalence of AF differs with each population studied, and research on non-Western populations and the oldest old is scarce. Methods: We used data from the 2012 wave of the Chinese Longitudinal Healthy Longevity Survey, a community-based study in eight longevity areas in China, to estimate AF prevalence in an elderly Chinese population (n = 1418, mean age = 85.6 years) and to identify risk factors. We determined the presence of AF in our participants using single-lead electrocardiograms. The weighted prevalence of AF was estimated in subjects stratified according to age groups (65–74, 75–84, 85–94, 95 years and above) and gender. We used logistic regressions to determine the potential risk factors of AF. Results: The overall prevalence of AF was 3.5%; 2.4% of men and 4.5% of women had AF (P < 0.05). AF was associated with weight extremes of being underweight or overweight/obese. Finally, advanced age (85–94 years), history of stroke or heart disease, low high-density lipoprotein levels, low triglyceride levels, and lack of regular physical activity were associated with AF. Conclusions: In urban elderly, AF prevalence increased with age (P < 0.05), and in rural elderly, women had higher AF prevalence (P < 0.05). Further exploration of population-specific risk factors is needed to address the AF epidemic.

Vitamin D Levels and the Risk of Cognitive Decline in Chinese Elderly People: the Chinese Longitudinal Healthy Longevity Survey

BACKGROUND Vitamin D has a neuroprotective function, potentially important for the prevention of cognitive decline. Prospective studies from Western countries support an association between lower vitamin D level and future cognitive decline in elderly people. No prospective study has examined this association in Asia. METHODS This community-based cohort study of elderly people in China follows 1,202 cognitively intact adults aged ≥60 years for a mean duration of 2 years. Plasma vitamin D level was measured at the baseline. Cognitive state of participants was assessed using the Mini-Mental State Examination (MMSE). Cognitive impairment was defined as an MMSE score <18. Cognitive decline was defined as ≥3 points decline from baseline. Multivariable logistic regression models were used to examine the association between quartiles of vitamin D levels with cognitive decline and incidence of cognitive impairment. RESULTS Participants with low vitamin D level had an increased risk of cognitive decline. Compared with the highest quartile of vitamin D levels, the multivariable odds ratios (ORs; 95% confidence interval) for cognitive decline were 2.1 (1.3-3.4) for the second highest quartile, 2.2 (1.4-3.6) for the third highest quartile, and 2.0 (1.2-3.3) for the lowest quartile. The multivariable ORs of incident cognitive impairment for the second highest, third highest, and lowest versus highest quartiles of vitamin D levels were 1.9 (0.9-4.1), 2.6 (1.2-5.6), and 3.2 (1.5-6.6), respectively. CONCLUSIONS This first follow-up study of elderly people, including the oldest-old, in Asia shows that low vitamin D levels were associated with increased risk of subsequent cognitive decline and impairment.

Short-Term Trajectories of Depressive Symptoms in Stroke Survivors and Their Family Caregivers.

GOAL We utilize group-based trajectory modeling (GBTM) to delineate depressive symptom trajectories among stroke survivor-caregiver dyads, to identify predictors of the delineated trajectories, and to assess the influence of time-varying covariates (stroke survivor depressive symptoms and functional disability, caregiver depressive symptoms, and foreign domestic worker [FDW] assistance) on the level of the depressive symptom trajectories. METHODS Data on 172 stroke survivor-caregiver dyads in Singapore, for whom depressive symptoms were assessed thrice (baseline/3 months/6 months), were utilized. GBTM was applied to delineate depressive symptom trajectories, and to identify their predictors and time-varying covariates. FINDINGS Three stroke survivor depressive symptom trajectories (low and decreasing [47.6%], low and increasing [43.1%], and high and increasing [9.3%]) and 2 caregiver depressive symptom trajectories (low and stable [71.5%] and high and decreasing [28.5%]) were delineated. Caregivers with chronic diseases were more likely (odds ratio [95% confidence interval]: 8.09[2.04-32.07]) and those caring for older stroke survivors (0.94[0.90-0.98]) were less likely to follow the high and decreasing than the low and stable depressive symptom trajectory. An increase in stroke survivor functional disability and caregiver depressive symptoms led to a rise (~worsening) in stroke survivor depressive symptom trajectories. Whereas an increase in stroke survivor depressive symptoms led to a rise in caregiver depressive symptom trajectories, FDW assistance led to a decline (~improvement). CONCLUSION Care professionals should be mindful of heterogeneity in depressive symptom patterns over time among stroke survivor-caregiver dyads. Reciprocal association of depressive symptoms in the stroke survivor-caregiver dyad suggests that addressing mood problems in 1 member may benefit the other member, and calls for dyadic mental health interventions.

Serum coenzyme Q10 and risk of disabling dementia: The Circulatory Risk in Communities Study (CIRCS)

OBJECTIVE To examine whether coenzyme Q10, a potent antioxidant, is associated with risk of dementia, which has not yet been elucidated. APPROACH AND RESULTS We performed a case-control study nested in a community-based cohort of approximately 6000 Japanese aged 40-69 years at baseline (1984-1994). Serum coenzyme Q10 was measured in 65 incident cases of disabling dementia with dementia-related behavioral disturbance or cognitive impairment incident between 1999 and 2004, and in 130 age-, sex- and baseline year-matched controls. Serum coenzyme Q10 was inversely associated with dementia: the multivariate odds ratios (95% confidence intervals) were 0.68 (0.26-1.78), 0.92 (0.33-2.56), and 0.23 (0.06-0.86) for individuals with the second, third, and highest quartiles of coenzyme Q10, respectively, as compared with the lowest quartile (P for trend = 0.05). A similar association was found for the coenzyme Q10/total cholesterol ratio: the respective ORs were 0.67 (0.25-1.78), 0.73 (0.28-1.92), and 0.21 (0.05-0.90) (P for trend = 0.04). CONCLUSIONS Serum coenzyme Q10 levels were inversely associated with risk of disabling dementia.