Cardiovascular risk factors and 18-month mortality and morbidity in an elderly Chinese population aged 70 years and over

The Epidemiology of Stroke in the East Asian Region: A Literature-Based Review

Stroke is a leading cause of morbidity and mortality in the developed world. Our objective was to review comparable studies of stroke incidence, prevalence, and subtypes in the East Asian region. English language epidemiologic studies of stroke published from 1984 through 2004 were identified for the East Asian region (China, Hong Kong, Taiwan, Japan, North and South Korea and the ASEAN countries). The Sudlow–Warlow criteria were modified to identify comparable studies. Stroke epidemiology is relatively well characterized in China, Taiwan, and Japan; however, little information is available for other countries. Four studies of stroke incidence, from China, Taiwan, and Japan, were identified, which reported a total of 4995 first-ever stroke events. There was an over twofold difference in the age-adjusted incidence of stroke between the Chinese Seven Cities and Okinawa study (483 vs 201 per 100 000). The 1-month case fatality rate ranged from 12·7% to 17·3%. Only one population-based study on stroke prevalence, from Taiwan, was identified: Studies show the relatively high proportion of hemorrhagic stroke (30%). Stroke epidemiology is relatively well characterized in China, Japan, and Taiwan but not in other countries in the region. More recent data are needed to monitor stroke prevention efforts and guide planning of health care resources in the region.

Body mass index, waist-hip ratio and risk of chronic medical condition in the elderly population: results from the Well-being of the Singapore Elderly (WiSE) Study

BACKGROUND

The aim of the current study was to establish the prevalence and relationship of Body Mass Index (BMI) and Waist-Hip Ratio (WHR) with chronic health conditions and their associated socio-demographic correlates in the elderly population of Singapore.

METHODS

The data was extracted from the Well-being of the Singapore Elderly (WiSE) study, a comprehensive single phase, cross-sectional, population-based, epidemiological study conducted in 2013 among Singaporean residents (n = 2565) aged 60 years and above with a mean age of 72.7 years (range 60 to 105, SD = 9.53). The respondents were assessed with anthropometric measurements including height, weight, BMI, waist circumference, hip circumference and WHR. Participants provided information on their socio-demographic details and chronic health conditions.

RESULTS

Prevalence of those who were obese, overweight, normal and underweight based on BMI was 8.7 %, 33.4 %, 52.5 % and 5.5 % respectively. Malays were more likely to be overweight compared to Chinese and Indians, while Malays and Indians were more likely to be obese compared to Chinese. Participants who were never married were less likely to be overweight compared to married. Participants aged 85 years and above were more likely to be underweight compared to those aged 60-75 years. Prevalence of high WHR (above 0.90 for men and 0.80 for women) was 79.8 % and this was more pervasive amongst Indians. Participants who were homemakers were more likely to have high WHR while those with tertiary education tended to have low WHR. Being overweight was associated with hypertension and heart problems, while obesity was associated with hypertension and diabetes, and a high WHR was associated with hypertension and diabetes. There were no significant differences in the other chronic conditions in this elderly population.

CONCLUSIONS

This study demonstrates the importance of anthropometric measurements in the elderly and its association with certain chronic physical conditions, indicating their utility in the clinical management of these conditions in the elderly.

Physical Activity and Risk of Coronary Heart Disease and Stroke in Older Adults: The Cardiovascular Health Study

BACKGROUND

Although guidelines suggest that older adults engage in regular physical activity (PA) to reduce cardiovascular disease (CVD), surprisingly few studies have evaluated this relationship, especially in those >75 years. In addition, with advancing age the ability to perform some types of PA might decrease, making light-moderate exercise such as walking especially important to meet recommendations.

METHODS AND RESULTS

Prospective cohort analysis among 4207 US men and women of a mean age of 73 years (standard deviation=6) who were free of CVD at baseline in the Cardiovascular Health Study were followed from 1989 to 1999. PA was assessed and cumulatively updated over time to minimize misclassification and assess the long-term effects of habitual activity. Walking (pace, blocks, combined walking score) was updated annually from baseline through 1999. Leisure-time activity and exercise intensity were updated at baseline, 1992, and 1996. Incident CVD (fatal or nonfatal myocardial infarction, coronary death, or stroke) was adjudicated using medical records. During 41,995 person-years of follow-up, 1182 CVD events occurred. After multivariable adjustment, greater PA was inversely associated with coronary heart disease, stroke (especially ischemic stroke), and total CVD, even in those ≥75 years. Walking pace, distance, and overall walking score, leisure-time activity, and exercise intensity were each associated with lower risk. For example, in comparison with a walking pace <2 mph, those that habitually walked at a pace >3 mph had a lower risk of coronary heart disease (0.50; confidence interval, 0.38-0.67), stroke (0.47; confidence interval, 033-0.66), and CVD (0.50; confidence interval, 0.40-0.62).

CONCLUSIONS

These data provide empirical evidence supporting PA recommendations, in particular, walking, to reduce the incidence of CVD among older adults.

A comparison of risk factors as predictors of cardiovascular and non-cardiovascular mortality in the elderly people--relevance of N-terminal pro-B-type natriuretic peptide and low systolic blood pressure

BACKGROUND

Many risk factors are known to predict ischaemic events and mortality in the elderly people, but their ranking of importance remains uncertain. This study was designed to identify and compare the main predictors of total mortality (TM), cardiovascular mortality (CVM) and non-cardiovascular mortality (NCVM) in older adults.

METHODS

Nine hundred and seventy-nine community resident adults aged ≥ 65 years, free of previous heart failure and cardiovascular events, participated in the study. The univariate and multivariate (Cox regression) relationships of baseline cardiovascular risk factors, treatments and laboratory data with TM, CVM and NCVM were assessed after a median follow up of 6.7 years.

RESULTS

Overall, there were 104 deaths (30 because of CVM and 74 to NCVM). In multivariate analysis, the following factors remained independently associated with mortality: NT pro-B-type natriuretic peptide (NT-proBNP) upper quintile (≥ 237 pg/ml for men, ≥ 280 pg/ml for women): hazard ratio (HR) vs. the rest of the population (95% confidence interval) 2.34 (1.52-3.60), p < 0.001 for TM; HR 5.41 (2.32-12.65), p < 0.001 for CVM; systolic blood pressure lower quintile (≤ 130 mmHg): HR 3.06 (1.80-5.21), p < 0.001 for NCVM; diabetes: HR 2.46 (1.29-4.72), p = 0.007 for NCVM; erythrocyte sedimentation rate (ESR) upper decile (≥ 41 mm/h): HR 2.33 (1.16-4.69), p = 0.02 for NCVM; platelet count lower quintile (≤ 177 × 10(9) /l): HR 2.09 (1.20-3.64), p = 0.009 for NCVM; ever-smoker status: HR 2.08 (1.23-3.52), p = 0.007 for NCVM.

CONCLUSIONS

In elderly community dwellers, NT-proBNP was the strongest predictor of TM and CVM, while especially low systolic blood pressure, together with diabetes, ESR, reduced platelet count and ever-smoker status, were the main predictors of NCVM.

A systematic review of body fat distribution and mortality in older people

We conducted a systematic review investigating body fat distribution in older adults and its association with morbidity and mortality. Our search yielded 2702 citations. Following three levels of screening, 25 studies were selected to evaluate the association between body fat distribution and comorbidity, and 17 studies were used in the mortality analysis. Most of the selected studies in our analyses used anthropometric measures, e.g., body mass index (BMI), waist circumference, and waist-hip ratio; relatively few studies used direct measures, such as body fat/lean mass, and percentage body fat. Studies reported inconsistent findings regarding the strongest predictor(s) of morbidity and mortality. However, the majority of studies suggested that BMI per se was not the most appropriate predictor of morbidity and mortality in the elderly because of its inability to discern or detect age-related body fat redistribution. In addition, studies using BMI found that the optimal BMI range for the lowest mortality in the elderly was overweight (25 kg/m(2)≤BMI<30 kg/m(2)) or mildly obese (30 kg/m(2)≤BMI<35 kg/m(2)). Our findings suggest that the current clinical guidelines, recommending that overweight and obesity are major risk factors for increased morbidity and mortality are not applicable to this population. Therefore, the central message of this review is to advise the government to establish new guidelines specifically for this population, using a combination of body fat distribution measurements, and to certify that these guidelines will not be applied to inappropriate populations.

Nutritional strategies for successful aging

With increasing life expectancy in developed and developing countries, maintaining health and function in old age has become an important goal, including avoidance or optimal control of chronic diseases; maintenance or retarding the decline of physical and cognitive function; optimizing psychological health; and maintaining independent functioning in tasks related to self-care and societal interaction. This article discusses all of those, as well as other components of successful aging such as social network and socioeconomic status.

Ten-year cardiovascular risk in the general public of Hong Kong

BACKGROUND

Coronary heart disease (CHD) is a major health issue in Hong Kong and has become the second leading cause of death since the 1960s. The prevalence of CHD and its mortality in Hong Kong are approaching a level that requires focused attention. Unfortunately, CHD could be a silent disease until the manifestations occur. Early detection and control of cardiovascular risk factors including cholesterol and blood pressure are vital.

OBJECTIVE

The current project aimed to investigate the 10-year cardiovascular risk in the general public of Hong Kong.

DESIGN

A 12-month prospective cross-sectional study.

SETTING AND PATIENTS

General public of Hong Kong between April 2007 and April 2008.

INTERVENTION

Public screening of lipid panels and blood pressure.

MAIN OUTCOME MEASUREMENT

Estimation of 10-year cardiovascular risk.

RESULTS

During this period, a total of 2607 patients were recruited with a mean age of 46.4±11.1 years (51.3% male), and 8.1% of subjects were active smokers. Among all of the subjects, the mean total cholesterol was 5.42±1.28 mmol/l, and the mean high density cholesterol was 1.59±0.75 mmol/l. The mean systolic blood pressure was 121.7±19.5 mm Hg. The assessment of the 10-year cardiovascular risk showed that 13.8% of the subjects were moderately high to high-risk patients.

CONCLUSION

The general public in Hong Kong had a relatively high total cholesterol and normal-high systolic blood pressure. Almost two in every 10 Hong Kong citizens may have a 10-20% or more than 20% risk of developing CHD in the next 10 years.

Physical activity and risk of ischemic stroke in the Northern Manhattan Study

BACKGROUND

It is controversial whether physical activity is protective against first stroke among older persons. We sought to examine whether physical activity, as measured by intensity of exercise and energy expended, is protective against ischemic stroke.

METHODS

The Northern Manhattan Study is a prospective cohort study in older, urban-dwelling, multiethnic, stroke-free individuals. Baseline measures of leisure-time physical activity were collected via in-person questionnaires. Cox proportional hazards models were constructed to examine whether energy expended and intensity of physical activity were associated with the risk of incident ischemic stroke.

RESULTS

Physical inactivity was present in 40.5% of the cohort. Over a median follow-up of 9.1 years, there were 238 incident ischemic strokes. Moderate- to heavy-intensity physical activity was associated with a lower risk of ischemic stroke (adjusted hazard ratio [HR] 0.65, 95% confidence interval [0.44-0.98]). Engaging in any physical activity vs none (adjusted HR 1.16, 95% CI 0.88-1.51) and energy expended in kcal/wk (adjusted HR per 500-unit increase 1.01, 95% CI 0.99-1.03) were not associated with ischemic stroke risk. There was an interaction of sex with intensity of physical activity (p = 0.04), such that moderate to heavy activity was protective against ischemic stroke in men (adjusted HR 0.37, 95% CI 0.18-0.78), but not in women (adjusted HR 0.92, 95% CI 0.57-1.50).

CONCLUSIONS

Moderate- to heavy-intensity physical activity, but not energy expended, is protective against risk of ischemic stroke independent of other stroke risk factors in men in our cohort. Engaging in moderate to heavy physical activities may be an important component of primary prevention strategies aimed at reducing stroke risk.

Frailty Index as a Measure of Biological Age in a Chinese Population

BACKGROUND

The concept of a frailty index, developed in Canadian elderly populations as an indicator of biological age as opposed to chronological age, was tested in an elderly Chinese population to determine whether it is applicable in a different ethnic and cultural setting.

METHODS

A data set including 62 physical, psychological, and socioeconomic variables from a cohort of 2,032 persons 70 years and older (999 men, 1,033 women) was used. The distribution of the index was evaluated using the Cramer-von Mises goodness-of-fit test, and multiple linear regression was used to assess its relationship with age and sex. A biological age for each participant was calculated based on an inverse regression of age on mean frailty index and sex. The Cox proportional hazards regression model was used to assess the ability of biological age to predict death.

RESULTS

The distribution of the frailty index most closely resembled a Weibull distribution. The frailty index increased with age until the mid-80s, when it leveled off, and was higher in women than men for each age group. The distribution of biological age is wider than that for chronological age, and it strongly predicted death. Women had an estimated 20% lesser chance of dying at a given time than did men of the same chronological age and degree of frailty.

CONCLUSIONS

The study confirms the robustness of the concept and method of calculating the frailty index developed in elderly Canadian populations. It also suggests that the sex difference in life expectancy may have an underlying genetic basis independent of frailty.

Leisure time physical activity and mortality in Hong Kong: case-control study of all adult deaths in 1998

PURPOSE

Physical activity is associated with longevity; however, whether these beneficial effects extend to Chinese populations is unclear. We examined the relationship between leisure time physical activity (LTPA) and mortality in Hong Kong.

METHODS

Using a case-control study, past (10 years prior) levels of LTPA were ascertained via proxy informants for 24,079 dead cases (81% of all registered deaths) and 13,054 live controls aged #10878;35 years and were analyzed by unmatched logistic regression to determine their association with all-cause and cause-specific mortality.

RESULTS

Compared with an exercise frequency of <1 episode per month, > or = 1 episode of LTPA per month was inversely associated with all-cause mortality [multivariable odds ratio (OR)=0.63, 95% confidence interval (CI), 0.59, 0.68 for males; OR=0.75, 95% CI, 0.70, 0.80 for females; adjusted for age, education, smoking status, alcohol consumption, and physical demand at work]. Each activity level above the reference level of <1 episode per month (i.e., 1 episode per month to 1-3 episodes per week, > or = 4 episodes per week) had approximately the same level of risk reduction and no dose-response gradient was observed. The inverse association was stronger for cardiovascular than cancer deaths, particularly in males and was strongest for respiratory mortality. One-fifth of all 31,349 registered deaths in those aged 35 years and over in Hong Kong in 1998 were attributable to physical inactivity.

CONCLUSION

The present data confirm and extend previous findings in Caucasian populations on the association between leisure time physical activity and longevity. The population attributable risk from physical inactivity exceeds that due to tobacco smoking in this Hong Kong Chinese population. We predict mainland China will witness a similarly large mortality burden as it undergoes further socioeconomic development in the next few decades.

Physical inactivity, excess adiposity and premature mortality

The purpose of this report is to review the evidence that physical inactivity and excess adiposity are related to an increased risk of all-cause mortality, and to better identify the independent contributions of each to all-cause mortality rates. A variance-based method of meta-analysis was used to summarize the relationships from available studies. The summary relative risk of all-cause mortality for physical activity from the 55 analyses (31 studies) that included an index of adiposity as a covariate was 0.80 [95% confidence interval (CI) 0.78-0.821, whereas it was 0.82 [95% CI 0.80-0.84] for the 44 analyses (26 studies) that did not include an index of adiposity. Thus, physically active individuals have a lower risk of mortality by comparison to physically inactive peers, independent of level of adiposity. The summary relative risk of all-cause mortality for an elevated body mass index (BMI) from the 25 analyses (13 studies) that included physical activity as a covariate was 1.23 [95% CI 1.18-1.29], and it was 1.24 [95% CI 1.21-1.28] for the 81 analyses (36 studies) that did not include physical activity as a covariate. Studies that used a measure of adiposity other than the BMI show similar relationships with mortality, and stratified analyses indicate that both physical inactivity and adiposity are important determinants of mortality risk.

Relation Between Cardiovascular and Metabolic Disease and Cognition in Very Old Age: Cross-Sectional and Longitudinal Findings From the Berlin Aging Study

This study documented findings on the relation between cognitive functioning (perceptual speed, memory, fluency, and knowledge) and cardiovascular and metabolic disease in a sample of very old adults (ages 70 and older), both cross-sectionally (n=516) and longitudinally (n=206) in a 4-year follow-up. After age, SES, sex, and dementia status were controlled for, 4 diagnoses were negatively associated with cognition: congestive heart failure, stroke, coronary heart disease, and diabetes mellitus, with a joint effect of 0.47 standard deviations. The impact of disease status was largest on perceptual speed and fluency, memory was impacted only by diabetes, and knowledge was not related to any somatic diagnosis. There was no differential decline in participants diagnosed with 1 of these 4 diseases and those who were not. The only cardiovascular risk factor associated with cognitive performance was alcohol consumption.

Cardiovascular risk factors, monitoring, and therapy for HIV-infected patients

Cardiovascular complications are important contributors to morbidity and mortality in HIV-infected patients. These complications can usually be detected at subclinical levels with monitoring, which can help guide targeted interventions. This article reviews available data on types and frequency of cardiovascular manifestations in HIV-infected patients and proposes monitoring strategies aimed at early subclinical detection. In particular, we recommend routine echocardiography for HIV-infected patients, even those with no evidence of cardiovascular disease. We also review preventive and therapeutic cardiovascular interventions. For procedures that have not been studied in HIV-infected patients, we extrapolate from evidence-based guidelines for the general population.

Weak effect of hypertension and other classic risk factors in the elderly who have already paid their toll

The aim of the CASTEL, a population-based (n=3282) prospective study which began 14 years ago, was to identify those items which had a prognostic impact in the elderly, and to evaluate whether the typical cardiovascular risk factors, particularly arterial hypertension, play a role after the age of 65 years. Initial screening, final follow-up and annual detection of mortality were performed. Mantel-Hanszel approach and multivariate Cox model were used for statistics. Cardiovascular mortality was 23.3% in normotensive, 23.3% in borderline, and 25% in the sustained hypertensive subjects (insignificant difference). In women, the incidence of stroke and coronary artery disease weakly depended on pulse pressure. Historical stroke and myocardial infarction predicted cardiovascular mortality in women; diabetes, uricaemia and high heart rate in men. In the very old, the predictors were less numerous, and blood pressure was not a predictor whatsoever; pulse blood pressure and murmurs at the neck were especially predictive in women, historical heart failure, proteinuria and tachycardia in men, historical stroke and myocardial infarction, pulmonary disease, left ventricular hypertrophy, diabetes and uricaemia in both genders. The elderly have a different cardiovascular risk pattern compared to younger people. Hypertension is not a predictor of coronary and stroke mortality. Prognosis depends on pulse pressure rather than on the label 'hypertension'. Hypercholesterolaemia is not a risk factor. This could simply indicate that elderly persons are the survivors in a population where significant mortality has already made its mark, eliminating those with the worst risk pattern. The two genders have a different risk profile due to sex-specific susceptibility to risk factors.

Cardiovascular monitoring and therapy for HIV-infected patients

Cardiovascular complications are important contributors to morbidity and mortality in HIV-infected patients. These complications can usually be detected at subclinical levels with monitoring, which can help guide targeted interventions. This article reviews available data on types and frequency of cardiovascular manifestations in HIV+ patients and proposes monitoring strategies aimed at early subclinical detection. In particular, we recommend routine echocardiography for HIV+ patients, even those with no evidence of cardiovascular disease. We also review preventive and therapeutic cardiovascular interventions. For procedures that have not been studied in HIV+ patients, we extrapolate from evidence-based guidelines for the general population.

The effect of middle- and old-age body mass index on short-term mortality in older people

OBJECTIVES

To determine the effect of body mass index (BMI) at old age and at age 50 on short-term survival among persons age 65 and older.

DESIGN

Cross-sectional, using the 4,791 respondents to the community interview of the 1994 National Long Term Care Survey (NLTCS).

SETTING

United States of America.

PARTICIPANTS

Persons age 65 and older who lived in community settings as of the 1994 NLTCS interview.

MEASUREMENTS

Short-term mortality was measured from the date of the 1994 NLTCS through year-end 1995. BMI (kg/m2) (at three points: 1994 NLTCS, 1 year before, age 50) and all other variables, including three other modifiable risk factors known to be related to mortality--cigarette smoking, alcohol consumption, and exercise--were based on self-report.

RESULTS

Both the unadjusted and adjusted nadirs of mortality in relation to BMI at old age were found in older persons with a BMI between 30 and 34.9; this was true for males and females in all age groups. The highest mortality rates were found for older persons with very low BMI (<18.5). In contrast, BMI at age 50 was positively related to mortality, with those in the lowest BMI category (<18.5) at age 50 having the lowest mortality. Persons who were obese at age 50 and who were no longer obese at the 1994 NLTCS had lower mortality than persons with stable weight.

CONCLUSIONS

Weight reduction by middle-aged persons who are obese should be reinforced as a public health priority, because there is evidence that long-term weight loss results in better short-term survival. Further study of healthy older survivors to determine why they are not harmed by heavier weight in old age may provide useful insights into successful aging.

Circadian variation of stroke onset in Hong Kong Chinese: a hospital-based study

Circadian variation of onset of transient ischaemic attack (TIA) or stroke during four 6-hourly periods starting from midnight was studied in Hong Kong Chinese patients admitted to a regional hospital between October 1996 and July 1999. The onset was classifiable into one of the 6-hourly periods in 832 of 905 patients; patients with unclassifiable onset were more likely to have lacunar infarct and less likely to have intracerebral haemorrhage (ICH). There was a significant circadian variation of onset in all strokes and TIA, TIA alone, ischaemic stroke (IS), ICH and different IS subtypes. The risk of onset was greatest between 6 a.m. and noon for IS or TIA, but between noon and 6 p.m. for ICH. There was no difference in the circadian variation between patients with and without prior TIA or stroke. This hospital-based study revealed a significant circadian variation of onset in different types and subtypes of stroke.

The Bambuí health and ageing study (BHAS): methodological approach and preliminary results of a population-based cohort study of the elderly in Brazil

OBJECTIVE

A cohort study has been designed to identify predictors of adverse health events in the elderly. The methodology of the study and preliminary descriptive results are presented.

METHODS

The study population comprises all residents of Bambuí (Minas Gerais, Brazil), aged 60 or more years (n=1.742). From these, 92.2% were interviewed and 85.9% underwent clinical examination, consisting of haematological and biochemical tests, serology for Trypanosoma cruzi, anthropometric and blood pressure measures and electrocardiogram. Aliquots of serum, plasma and DNA were stored for future investigations. The baseline interview included sociodemographic characteristics, self-referred health condition and history of selected diseases, medication use, health service use, source of medical care, physical activities, smoking, drinking and eating habits, reproductive history, physical functioning, life events, social support and mental health. Individuals are being followed up annually.

RESULTS

The following characteristics predominated among participants: women (60,0%), married (48.9%) or widowed (35.4%), people living in households with up to 2 residents (73.8%), heads of family (76.7%), people with monthly income between 1.00 and 2.99 Brazilian minimum wages (62.0%) and people with up to 4 years of schooling (89.1%). The median age was 68 years. Among the cohort members, only 1.7% were lost in the first follow-up.

CONCLUSIONS

In general, the characteristics of the study population were very similar to those from other epidemiological studies of the elderly based on large Brazilian cities. The small number of losses to follow-up indicates that the choice of Bambuí was adequate, assuring the feasibility of a long term cohort study.

Mediterranean diet and age with respect to overall survival in institutionalized, nonsmoking elderly people

BACKGROUND

In studies from Italy and Greece, a Mediterranean dietary pattern was shown to favorably affect life expectancy in the elderly population. This pattern is thought to reduce the risk of cancer in addition to being cardioprotective.

OBJECTIVE

The objective of this study was to evaluate the interactive effects of the Mediterranean diet and age with respect to survival after controlling for several other variables that could be considered as confounders: age, sex, body mass index, albumin concentration, physical activity, self-assessment of health, and dieting in response to chronic conditions.

DESIGN

This was a cohort study involving 161 nonsmoking elderly subjects (74 subjects aged <80 y and 87 subjects aged > or =80 y) living in Spain. The subjects were followed up for > or =9 y. Diet was assessed with a semiquantitative food-frequency questionnaire.

RESULTS

A diet score based on 8 characteristics of the traditional diet in the Mediterranean region was associated with a significant reduction in overall mortality in elderly subjects aged <80 y but not in subjects aged > or =80 y. A unit increase in the diet score predicted a 31% reduction in mortality in subjects aged <80 y (95% CI: 7%, 57%).

CONCLUSION

Efforts to promote adherence to the Mediterranean dietary pattern appear to be worthwhile in persons aged <80 y, in whom the diet predicts survival, but we do not have any available evidence that such a diet benefits subjects aged > or =80 y.

Smoking and mortality in an older Chinese cohort

OBJECTIVES

Only limited data are available regarding smoking and health in later life and, in particular, in the older Chinese population. This paper reports the relationship between smoking and mortality in a Chinese cohort aged 70 years and older.

SETTING

A population-based study conducted in Hong Kong.

PARTICIPANTS

A cohort comprising 2030 subjects aged 70 and older were assembled in 1991-1992 and followed for 36 months.

DESIGN

A prospective cohort study.

MEASUREMENTS

Baseline information regarding smoking status as well as several social and health variables were obtained through face-to-face interview at the respondent's place of residence. The outcome variables were mortality from all causes as well as from cancer and cardiovascular and respiratory diseases. Causes of death were ascertained from death certificates.

RESULTS

The prevalence rates of smoking at baseline were 24.9% in men and 8.2% in women. A total of 534 deaths occurred during the 36-month follow-up period. Of these, 447 were attributable to three main causes: cancer, cardiovascular disease, and respiratory disease. Elevated mortality risks from all causes were observed among both male (RR = 1.4; 95% CI, 0.9-1.9) and female (RR = 1.6; 95% CI, 1.0-2.5) current smokers, but the 95% confidence intervals overlapped. Significant association between current smoking and combined mortality from these three major causes was found in men; it was also found in women after excluding those with these diseases at baseline. More than a 3-fold increased risk of cancer mortality was found in current smokers of both sexes. Although nonsignificant associations were found between former smokers and mortality risks in men, women who were former smokers had increased mortality risks from all causes as well as from cancer and respiratory diseases.

CONCLUSIONS

This 3-year prospective study of an older Chinese cohort reveals the impact of smoking on health during later life, especially in women. Smoking cessation, particularly in older men, should be beneficial in reducing mortality. Smoking cessation should begin as early as possible for women.

Physical activity and ischemic stroke risk. The atherosclerosis risk in communities study

BACKGROUND AND PURPOSE

The relationship between physical activity and stroke is inconclusive according to the 1996 US Surgeon General's Report on Physical Activity and Health. Therefore, this study examined the relationship between physical activity and ischemic stroke risk among 14 575 Atherosclerosis Risk in Communities Study participants aged 45 to 64 years free of self-reported stroke and coronary heart disease at baseline.

METHODS

Eligible potential stroke hospitalizations were identified from ongoing hospital surveillance and from hospitalizations reported by the cohort study participants. All strokes were validated by hospitalization records. Physical activity was measured as sport, leisure (nonsport), and work with the use of the Baecke questionnaire. Multivariable Poisson and Cox proportional hazards models were used to determine the association of differing levels of physical activity with ischemic stroke incidence.

RESULTS

During an average of 7.2 years of follow-up, 189 incident ischemic strokes occurred. Ischemic stroke incidence rates were highest in the lowest quartile of sport, leisure, and work scores. The hazard rate ratios with 95% CIs for ischemic stroke for the highest quartile compared with the lowest quartile of activity adjusted for age, sex, race-center, education, and smoking, were sport 0.83 (0.52, 1.32), leisure 0.89 (0.57, 1.37), and work 0.69 (0.47, 1.00). Further adjustment for factors that likely were intermediate variables (hypertension, diabetes, fibrinogen, and body mass index) between physical activity and stroke attenuated the associations.

CONCLUSIONS

Our findings suggest that physical activity was weakly associated with a reduced risk of ischemic stroke among middle-aged adults. The association may be due to links between physical activity and other risk factors or due to chance.