Risk Factors of Stroke Mortality: A 40-Year Follow-Up of the Corfu Cohort from the Seven-Countries Study

Physical functioning in patients with ankylosing spondylitis: comparing approaches of experienced ability with self-reported and objectively measured physical activity

BACKGROUND

Physical functioning can be assessed by different approaches that are characterized by increasing levels of individual appraisal. There is insufficient insight into which approach is the most informative in patients with ankylosing spondylitis (AS) compared with control subjects.

OBJECTIVE

The objective of this study was to compare patients with AS and control subjects regarding 3 approaches of functioning: experienced ability to perform activities (Bath Ankylosing Spondylitis Functional Index [BASFI]), self-reported amount of physical activity (PA) (Baecke questionnaire), and the objectively measured amount of PA (triaxial accelerometer).

METHODS

This case-control study included 24 AS patients and 24 control subjects (matched for age, gender, and body mass index). Subjects completed the BASFI and Baecke questionnaire and wore a triaxial accelerometer. Subjects also completed other self-reported measures on disease activity (Bath AS Disease Activity Index), fatigue (Multidimensional Fatigue Inventory), and overall health (EuroQol visual analog scale).

RESULTS

Both groups included 14 men (58%), and the mean age was 48 years. Patients scored significantly worse on the BASFI (3.9 vs 0.2) than their healthy peers, whereas PA assessed by Baecke and the accelerometer did not differ between groups. Correlations between approaches of physical functioning were low to moderate. Bath Ankylosing Spondylitis Functional Index was associated with disease activity (r = 0.49) and physical fatigue (0.73) and Baecke with physical and activity related fatigue (r = 0.54 and r = 0.54), but total PA assessed by accelerometer was not associated with any of these experience-based health outcomes.

CONCLUSIONS

Different approaches of the concept physical functioning in patients with AS provide different information. Compared with matched control subjects, patients with AS report more difficulties but report and objectively perform the same amount of PA.

Measuring Free-Living Energy Expenditure and Physical Activity with Triaxial Accelerometry

OBJECTIVE

To investigate the ability of a newly developed triaxial accelerometer to predict total energy expenditure (EE) (TEE) and activity-related EE (AEE) in free-living conditions.

RESEARCH METHODS AND PROCEDURES

Subjects were 29 healthy subjects between the ages of 18 and 40. The Triaxial Accelerometer for Movement Registration (Tracmor) was worn for 15 consecutive days. Tracmor output was defined as activity counts per day (ACD) for the sum of all three axes or each axis separately (ACD-X, ACD-Y, ACD-Z). TEE was measured with the doubly labeled water technique. Sleeping metabolic rate (SMR) was measured during an overnight stay in a respiration chamber. The physical activity level was calculated as TEE x SMR(-1), and AEE was calculated as [(0.9 x TEE) - SMR]. Body composition was calculated from body weight, body volume, and total body water using Siri's three-compartment model.

RESULTS

Age, height, body mass, and ACD explained 83% of the variation in TEE [standard error of estimate (SEE) = 1.00 MJ/d] and 81% of the variation in AEE (SEE = 0.70 MJ/d). The partial correlations for ACD were 0.73 (p < 0.001) and 0.79 (p < 0.001) with TEE and AEE, respectively. When data on SMR or body composition were used with ACD, the explained variation in TEE was 90% (SEE = 0.74 and 0.77 MJ/d, respectively). The increase in the explained variation using three axes instead of one axis (vertical) was 5% (p < 0.05).

DISCUSSION

The correlations between Tracmor output and EE measures are the highest reported so far. To measure daily life activities, the use of triaxial accelerometry seems beneficial to uniaxial.

Physical activity and body composition in patients with ankylosing spondylitis

OBJECTIVE

Patients with ankylosing spondylitis (AS) are at risk for accelerated muscle loss and reduced physical activity. Accurate data are needed on body composition and physical activity in this patient group. The purpose of this study was to investigate body composition and objectively assessed physical activity in patients with AS.

METHODS

Twenty-five AS patients (15 men, mean ± SD age 48 ± 11 years) were compared with 25 healthy adults matched for age, sex, and body mass index. Body composition was measured using a 3-compartment model based on air-displacement plethysmography to assess body volume and deuterium dilution to assess total body water. The fat-free mass index (FFMI; fat-free mass divided by height squared) and the percent fat mass (%FM) were calculated. Daily physical activity was assessed for 7 days using a triaxial accelerometer and physical fitness with an incremental test until exertion on a bicycle ergometer. Blood samples were taken to determine C-reactive protein (CRP) level and tumor necrosis factor α.

RESULTS

Accelerometer output (kilocounts/day) showed the same physical activity level for patients and controls (mean ± SD 319 ± 105 versus 326 ± 66). There was no difference in the FFMI or %FM between the patients and controls. Physical activity was positively related to the FFMI (partial R = 0.38, P = 0.01) and inversely related to CRP level (R = -0.39, P < 0.01), independent of group. CRP level was inversely related to the FFMI, but the effect was less strong than with physical activity (partial R = -0.31, P = 0.03).

CONCLUSION

Daily physical activity may help preserve fat-free mass in patients with AS.

[Measure of fitness and physical activity related to cardiovascular diseases and death]

The quality of fitness (aerobic capacity, maximal endurance performance or highly related physiological parameters) or physical activity improving fitness show a tight, reverse correlation to the all-cause and to the cardiovascular mortality within. The most fit one third of the population expect a 30-40 percent smaller chance for cardiovascular events, compared to the less fit third quarter. Low fitness (that can be changed) is just as a threatening risk factor as the traditional ones, its detection calls out for simple interventions to improve fitness: proper physical exercise.

Exercise as stroke prophylaxis

BACKGROUND

Stroke is the third most common cause of death in industrialized countries, accounting for more than 10% of deaths over age 65. Most strokes are due to arteriosclerosis. Regular physical activity lowers arterial blood pressure and body weight and improves glucose and lipid metabolism, thereby slowing the development of arteriosclerosis and its cardiovascular complications, particularly myocardial infarction. This review focuses on the question whether physical activity might also have a preventive effect on cerebral infarction and hemorrhage.

METHODS

This analysis is based on 33 prospective cohort studies and 10 case-control studies that addressed the potential effect of physical activity on stroke-related morbidity and mortality.

RESULTS

Our meta-analysis shows that physical activity reduces the risk of all types of stroke (infarction, hemorrhage, and stroke of unspecified type). The relative risk (RR) of fatal or non-fatal cerebral infarction is 0.75, while the corresponding figures for cerebral hemorrhage and stroke of unspecified type are 0.67 and 0.71, respectively. The reduction of risk is only statistically significant for men. The case-control studies show an RR of 0.32 for men and women combined.

CONCLUSIONS

When a multivariate analysis is performed that takes other vascular risk factors into account, physical activity is found to have an independent protective effect against cerebrovascular events. The effect is statistically significant only for men, not for women.

General psychiatric or depressive symptoms were not predictive for mortality in a healthy elderly cohort in Southern Brazil

General psychiatric symptoms may interfere with the ability of individuals to take care of their health, to get involved with activities and develop social abilities, thereby increasing risk of death.

Physical activity assessment with accelerometers: an evaluation against doubly labeled water

This review focuses on the ability of different accelerometers to assess daily physical activity as compared with the doubly labeled water (DLW) technique, which is considered the gold standard for measuring energy expenditure under free-living conditions. The PubMed Central database (U.S. NIH free digital archive of biomedical and life sciences journal literature) was searched using the following key words: doubly or double labeled or labeled water in combination with accelerometer, accelerometry, motion sensor, or activity monitor. In total, 41 articles were identified, and screening the articles' references resulted in one extra article. Of these, 28 contained sufficient and new data. Eight different accelerometers were identified: 3 uniaxial (the Lifecorder, the Caltrac, and the CSA/MTI/Actigraph), one biaxial (the Actiwatch AW16), 2 triaxial (the Tritrac-R3D and the Tracmor), one device based on two position sensors and two motion sensors (ActiReg), and the foot-ground contact pedometer. Many studies showed poor results. Only a few mentioned partial correlations for accelerometer counts or the increase in R(2) caused by the accelerometer. The correlation between the two methods was often driven by subject characteristics such as body weight. In addition, standard errors or limits of agreement were often large or not presented. The CSA/MTI/Actigraph and the Tracmor were the two most extensively validated accelerometers. The best results were found for the Tracmor; however, this accelerometer is not yet commercially available. Of those commercially available, only the CSA/MTI/Actigraph has been proven to correlate reasonably with DLW-derived energy expenditure.

The significance of various blood pressure indices for long-term stroke, coronary heart disease, and all-cause mortality in men: the Israeli Ischemic Heart Disease study

BACKGROUND AND PURPOSE

Studies of blood pressure (BP) indices as disease predictors have offered conflicting conclusions. We compare pulse pressure (PP), systolic BP (SBP) and diastolic BP (DBP), and mean arterial pressure (MAP) as risk markers for long-term mortality with emphasis on stroke.

METHODS

Male civil servants (40 to 65 years of age; n=9611) were examined in 1963 and followed up until 1986. Multivariate analysis was used to assess the association between BP indices and subsequent mortality. Stroke mortality was analyzed separately for initially normotensive (SBP< or =140 and DBP< or =90 mm Hg), hypertensive (SBP>140 and DBP>90 mm Hg), and men with isolated systolic hypertension (ISH; SBP>140 and DBP< or =90 mm Hg).

RESULTS

During follow-up, 3167 men died, including 932 of coronary heart disease and 339 of stroke. All 4 BP indices were predictive of fatal stroke among hypertensive and normotensive men (hazard ratios [HRs] fluctuated between 1.59 and 2.51). In models with 2 BP indices among normotensive men, SBP but not DBP remained a predictor of stroke mortality. MAP and PP were independent predictors of stroke mortality. Among hypertensive men, SBP and DBP were independent predictors of stroke mortality (HRs, 1.68 and 1.51, respectively). MAP but not PP remained a predictor of stroke mortality. In men with ISH, the 4 BP indices predicted fatal stroke, with HRs fluctuating between 1.24 and 2.04.

CONCLUSIONS

All 4 BP indices were predictors of stroke mortality among hypertensive and normotensive men, with DBP possibly the weaker predictor among the latter. Models with 2 BP indices yielded complex associations.

Total cholesterol and body mass index in relation to 40-year cancer mortality (the Corfu cohort of the seven countries study)

PURPOSE

We evaluated risk factors of cancer mortality based on a 40-year follow-up of the Corfu cohort (Seven Countries Study).

MATERIAL AND METHODS

The population studied in this analysis consisted of 529 rural men (49 +/- 6 years old) enrolled in 1961. Since then, periodic visits every 5 years were made to define the causes of death of the participants. Cox proportional hazards models evaluated various risk factors in relation to cancer mortality.

RESULTS

The death rate at the end of the follow-up was 87.1% (i.e., 461 deaths in 529 participants). Of those deaths, 118 (25.6%) were because of cancer (30 deaths were due to cancer of trachea, bronchus, and lung, and the rest were due to other malignant neoplasms). Cancer was the second cause of death in this cohort, after coronary heart disease. Age (hazard ratio, 1.05 per year; P < 0.05), smoking (hazard ratio, 1.97; P < 0.01), total serum cholesterol levels (hazard ratio, 0.95 per 10 mg/dL; P < 0.05), and body mass index (hazard ratio, 0.93 per 1 kg/m2; P < 0.05) showed a significant association with cancer deaths after controlling for physical activity status and anthropometric indices. It should be noted that the protective effect of total cholesterol on cancer mortality was observed only between 183 and 218 mg/dL baseline levels.

CONCLUSION

Cancer was one of the leading causes of death in this cohort. Smoking was associated with increased risk of cancer, whereas moderate total serum cholesterol and increased body and mass index seemed to have a protective effect on 40-year cancer mortality.

Long-term predictors of survival for the Seven Countries Study cohort from Crete: from 1960 to 2000

BACKGROUND

In 1960, all male inhabitants of a series of villages in rural Crete, born between 1900 and 1919, were invited to participate in the Seven Countries Study. Analysis of 25-year mortality data from the 16 cohorts of participants indicated that the cohort from Crete had the lowest age-standardised all-cause and coronary heart disease death rates.

METHODS

At baseline, 686 Cretan men (98% of those invited) participated in health examinations. Mortality data were collected over 40 years. Time-fixed and updated covariate survival analysis techniques were applied to assess eight cardiovascular disease risk factors as long-term predictors of all-cause and cardiovascular disease mortality.

RESULTS

The median survival time was 32 years. All-cause and cardiovascular mortality rates were 26 and 11 per 1000 person-years, respectively. Age (relative risk 1.11, 95% CI 1.09-1.13), diastolic blood pressure (relative risk 1.02, 95% CI 1.01-1.03), and smoking (relative risk 1.37, 95% CI 1.14-1.64) were positively associated and forced expiratory volume (relative risk 0.50, 95% CI 0.36-0.68) was negatively associated with all-cause mortality. Age (relative risk 1.13, 95% CI 1.09-1.16), diastolic blood pressure (relative risk 1.01, 95% CI 1.001-1.03), and forced expiratory volume (relative risk 0.53, 95% CI 0.32-0.89) were independent predictors of cardiovascular mortality. Serum cholesterol concentration and body mass index were not independently associated with death risk.

CONCLUSIONS

The Cretan cohort displays favourable 40-year survival. Even so, long-term predictors of the hazard of both all-cause and cardiovascular disease mortality are present.

Physical activity and stroke risk

Stroke represents a leading cause of morbidity and mortality especially among the elderly people, and therefore the need for effective preventive strategies is imperative. The value of physical activity for stroke prevention is not as well established as for other cardiovascular diseases. Despite some conflicting results, the majority of published studies have demonstrated a negative association between physical activity and stroke risk. In this article, we provide a concise overview of the epidemiological studies that investigate this association as well as a comprehensive analysis of the most relevant underlying pathophysiological mechanisms.

Mejora de la forma física como terapia antienvejecimiento

Several recent important studies have clearly shown that a low physical fitness represents a potent risk factor and even a predictor of both cardiovascular and all-causes morbidity and mortality. As a consequence, physical fitness assessment should be performed at the clinical level since, when properly assessed, it is a highly valuable health and life expectancy indicator. Based on the results of fitness assessment in a particular person and knowing his/her life style and daily physical activity, an individually adapted training program can be prescribed. This training program will allow that person to develop his/her maximal physical potential while improving his/her physical and mental health and attenuating the deleterious consequences of aging. In fact, physical exercise is today proposed as a highly effective means to treat and prevent major morbidity and mortality causes in industrialized countries. Most of these causes are associated with the aging process. In order to be effective, this type of intervention should be directed to improve the aerobic capacity and strength. In addition, it should be complemented with work directed to improve the general coordination and flexibility. Finally, diet optimization and use of nutritional supplements and legal ergogenic aids are key elements to improve the functional capacity and health, all of which is synonymous of anti-aging interventions.