Physical activity and cause-specific mortality in the Whitehall study

Long Term Implications of Home Healthcare Management on Mortality in Older Adults with Functional Difficulties in the Saudi Community

Background: This study aims to investigate whether certain demographic factors of patients receiving home healthcare (HHC) interventions have any positive impact on mortality. Methods: the study included all patients who were enrolled in the HHC program in a referred medical complex, Jeddah, Saudi Arabia between the years 2017 and 2020 (593 patients). Results: A total of 6548 HHC visits were received during the study period. From the total number of visits, 3592 (54.9%) HHC visits were scheduled in the year 2020 compared to 157 (2.4%) scheduled HHC visits in 2017 (p < 0.001). The most successful HHC visits were provided in 2020 compared with the year 2017 (2193 vs. 132; p < 0.001). The cancelled HHC visits were observed to be the lowest (194) in 2019. Three explanatory variables of mortality [age, having a major diagnosis (diabetes mellitus, cerebrovascular diseases, and bedridden), and having more cancelled visits] made a statistically significant contribution to the logistic regression model after controlling for other variables. Suffering from cerebrovascular diseases and/or bedridden were the strongest predictor of death in patients receiving HHC. Conclusions: During the 2020 pandemic, there was a sharp increase in HHC compared to previous years. Three significant explanatory variables of mortality [age, having a major diagnosis (diabetes mellitus, cerebrovascular diseases, and bedridden), and having more cancelled visits] were reported.

Bladder cancer and exeRcise trAining during intraVesical thErapy-the BRAVE trial: a study protocol for a prospective, single-centre, phase II randomised controlled trial

INTRODUCTION

Non-muscle invasive bladder cancer (NMIBC) accounts for about 75% of newly diagnosed bladder cancers. The treatment for NMIBC involves surgical removal of the tumour followed by 6 weekly instillations of immunotherapy or chemotherapy directly into the bladder (ie, intravesical therapy). NMIBC has a high rate of recurrence (31%-78%) and progression (15%). Moreover, bladder cancer and its treatment may affect patient functioning and quality of life. Exercise is a safe and effective intervention for many patient with cancer groups, however, no studies have examined exercise during intravesical therapy for NMIBC. The primary objective of the Bladder cancer and exeRcise trAining during intraVesical thErapy (BRAVE) trial is to examine the safety and feasibility of an exercise intervention in patients with bladder cancer undergoing intravesical therapy. The secondary objectives are to investigate the preliminary efficacy of exercise on health-related fitness and patient-reported outcomes; examine the social cognitive predictors of exercise adherence; and explore the potential effects of exercise on tumour recurrence and progression.

METHODS AND ANALYSIS

BRAVE is a phase II randomised controlled trial that aims to include 66 patients with NMIBC scheduled to receive intravesical therapy. Participants will be randomly assigned to the exercise intervention or usual care. The intervention consists of three supervised, high-intensity interval training sessions per week for 12 weeks. Feasibility will be evaluated by eligibility, recruitment, adherence and attrition rates. Preliminary efficacy will focus on changes in cardiorespiratory fitness and patient-reported outcomes from baseline (prior to intravesical therapy) to pre-cystoscopy (3 months). Cancer outcomes will be tracked at 3 months, and 1-year follow-up by cystoscopy. Analysis of covariance will compare between-group differences at post-intervention (pre-cystoscopy) for all health-related fitness and patient-reported outcomes.

ETHICS AND DISSEMINATION

The study was approved by the Health Research Ethics Board of Alberta-Cancer Committee (#20-0184). Dissemination will include publication and presentations at scientific conferences and public channels.

TRIAL REGISTRATION NUMBER

NCT04593862; Pre-results.

Physical Activity and Mortality in Cancer Survivors: A Systematic Review and Meta-Analysis

Background

Recommendations for improved survival after cancer through physical activity (PA) exist, although the evidence is still emerging. Our primary objective was to conduct a systematic review and meta-analysis of the association between prediagnosis and postdiagnosis PA and survival (cancer-specific, all-cause, and cardiovascular disease mortality) for all cancers and by tumor site. Secondary objectives were to examine the associations within population subgroups, by PA domain, and to determine the optimal dose of PA related to survival.

Methods

PubMed, EMBASE, and SportsDiscus databases were searched from inception to November 1, 2018. DerSimonian-Laird random-effects models were used to estimate the summary hazard ratios (HRs) and 95% confidence intervals (CI) for primary and secondary analyses and to conduct dose-response analyses.

Results

Evidence from 136 studies showed improved survival outcomes with highest vs lowest levels of prediagnosis or postdiagnosis total or recreational PA for all-cancers combined (cancer specific mortality: HR = 0.82, 95% CI = 0.79 to 0.86, and HR = 0.63, 95% CI = 0.53 to 0.75, respectively) as well as for 11 specific cancer sites. For breast and colorectal cancers, greater reductions were observed for postdiagnosis PA (HR = 0.58–0.63) compared with prediagnosis PA (HR = 0.80–0.86) for cancer-specific and all-cause mortality. Survival benefits through PA were observed in most subgroups (within sex, body mass index, menopausal status, colorectal subtypes, and PA domain) examined. Inverse dose-response relationships between PA and breast cancer-specific and all-cause mortality were observed, with steep reductions in hazards to 10–15 metabolic equivalent hours per week.

Conclusion

Higher prediagnosis and postdiagnosis levels of PA were associated with improved survival outcomes for at least 11 cancer types, providing support for global promotion of PA guidelines following cancer.

Social Determinants of Physical Activity Among Adult Asian-Americans: Results from a Population-Based Survey in California

The objective of this study was to evaluate the key social determinants of physical activity among six Asian-American subgroups using public access 2007 California Health Interview Survey data. Physical activity was defined as meeting the American College of Sports Medicine recommendation of 450 metabolic equivalent-minutes per week. Factors positively associated with meeting physical activity recommendations included being bilingual among Chinese and Vietnamese, and increasing age for Chinese only. On the other hand, being middle aged, currently married, and low neighborhood safety were significantly associated with lower odds of meeting physical activity recommendations, as were being female for Japanese and Koreans, and living above the poverty level for Vietnamese. Such results highlight the heterogeneity among Asian-Americans and need for health messages targeted at specific subgroups. Additionally, the role of built environment, particularly in areas with high Filipino residents, should be a public health priority for increasing physical activity outcomes.

Measured cardiorespiratory fitness and self-reported physical activity: associations with cancer risk and death in a long-term prospective cohort study

Physical activity is inversely associated with risk of some cancers. The relation with cancer‐specific death remains uncertain. Mainly, studies on relationships between physical activity and cancer are based on self‐reported physical activity (SPA). Hereby, we examined whether measured cardiorespiratory fitness (CRF) is associated with cancer risk, mortality, and case fatality. We also describe relationships between SPA and these outcomes, and between CRF and SPA. A cohort of 1997 healthy Norwegian men, aged 40–59 years at inclusion in 1972–75, was followed throughout 2012. At baseline, CRF was objectively measured. SPA (leisure time and occupational) was obtained through a questionnaire. Relationships between CRF or SPA, and the outcomes were estimated using Cox regression, adjusted for age, body mass index (BMI), and smoking. Pearson correlation coefficients evaluated agreements between CRF and SPA. During follow‐up, 758 men were diagnosed with cancer and 433 cancer deaths occurred. Analyses revealed lower cancer risk (Hazard ratio [HR] 0.85, 95% confidence intervals [CI]: 0.68–1.00), mortality (HR 0.68, 95% CI: 0.53–0.88), and case fatality (HR 0.74, 95% CI: 0.57–0.96), in men with high CRF compared to low CRF. Light leisure time SPA was associated with lower cancer risk (HR 0.70, 95% CI: 0.56–0.86) and mortality (HR 0.64 95% CI: 0.49–0.83), whereas strenuous occupational SPA was associated with higher risks (HR 1.42, 95% CI: 1.13–1.78 and HR 1.45, 95% CI: 1.09–1.93). Correlations between CRF and SPA were 0.351 (P < 0.001) and −0.106 (P < 0.001) for leisure time and occupational SPA, respectively. A high midlife CRF may be beneficial for cancer risk, cancer mortality, and case fatality.

Design of a study to determine the impact of insecticide resistance on malaria vector control: a multi-country investigation

Background

Progress in reducing the malaria disease burden through the substantial scale up of insecticide-based vector control in recent years could be reversed by the widespread emergence of insecticide resistance. The impact of insecticide resistance on the protective effectiveness of insecticide-treated nets (ITN) and indoor residual spraying (IRS) is not known. A multi-country study was undertaken in Sudan, Kenya, India, Cameroon and Benin to quantify the potential loss of epidemiological effectiveness of ITNs and IRS due to decreased susceptibility of malaria vectors to insecticides. The design of the study is described in this paper.

Methods

Malaria disease incidence rates by active case detection in cohorts of children, and indicators of insecticide resistance in local vectors were monitored in each of approximately 300 separate locations (clusters) with high coverage of malaria vector control over multiple malaria seasons. Phenotypic and genotypic resistance was assessed annually. In two countries, Sudan and India, clusters were randomly assigned to receive universal coverage of ITNs only, or universal coverage of ITNs combined with high coverage of IRS. Association between malaria incidence and insecticide resistance, and protective effectiveness of vector control methods and insecticide resistance were estimated, respectively.

Results

Cohorts have been set up in all five countries, and phenotypic resistance data have been collected in all clusters. In Sudan, Kenya, Cameroon and Benin data collection is due to be completed in 2015. In India data collection will be completed in 2016.

Discussion

The paper discusses challenges faced in the design and execution of the study, the analysis plan, the strengths and weaknesses, and the possible alternatives to the chosen study design.

Associations between active travel and weight, blood pressure and diabetes in six middle income countries: a cross-sectional study in older adults

BACKGROUND

There is little published data on the potential health benefits of active travel in low and middle-income countries. This is despite increasing levels of adiposity being linked to increases in physical inactivity and non-communicable diseases. This study will examine: (1) socio-demographic correlates of using active travel (walking or cycling for transport) among older adults in six populous middle-income countries (2) whether use of active travel is associated with adiposity, systolic blood pressure and self-reported diabetes in these countries.

METHODS

Data are from the WHO Study on Global Ageing and Adult Health (SAGE) of China, India, Mexico, Ghana, Russia and South Africa with a total sample size of 40,477. Correlates of active travel (≥150 min/week) were examined using logistic regression. Logistic and linear regression analyses were used to examine health related outcomes according to three groups of active travel use per week.

RESULTS

46.4% of the sample undertook ≥150 min of active travel per week (range South Africa: 21.9% Ghana: 57.8%). In pooled analyses those in wealthier households were less likely to meet this level of active travel (Adjusted Risk Ratio (ARR) 0.77, 95% Confidence Intervals 0.67; 0.88 wealthiest fifth vs. poorest). Older people and women were also less likely to use active travel for ≥150 min per week (ARR 0.71, 0.62; 0.80 those aged 70+ years vs. 18-29 years old, ARR 0.82, 0.74; 0.91 women vs. men). In pooled fully adjusted analyses, high use of active travel was associated with lower risk of overweight (ARR 0.71, 0.59; 0.86), high waist-to-hip ratio (ARR 0.71, 0.61; 0.84) and lower BMI (-0.54 kg/m(2), -0.98;- 0.11). Moderate (31-209 min/week) and high use (≥210 min/week) of active travel was associated with lower waist circumference (-1.52 cm (-2.40; -0.65) and -2.16 cm (3.07; -1.26)), and lower systolic blood pressure (-1.63 mm/Hg (-3.19; -0.06) and -2.33 mm/Hg (-3.98; -0.69)).

CONCLUSIONS

In middle-income countries use of active travel for ≥150 min per week is more common in lower socio-economic groups and appears to confer similar health benefits to those identified in high-income settings. Efforts to increase active travel levels should be integral to strategies to maintain healthy weight and reduce disease burden in these settings.

Patterns and correlates of objectively measured free-living physical activity in adults in rural and urban Cameroon

Background

Urbanisation in sub-Saharan Africa is changing lifestyles and raising non-communicable disease burden. Understanding the underlying pattern of physical activity and its correlates may inform preventive interventions. We examined correlates of objectively-measured physical activity in rural and urban Cameroon.

Methods

Participants were 544 adults resident in rural (W-156, M-89) or urban (W-189, M-110) regions. Physical activity was measured using individually-calibrated combined heart rate and movement sensing over seven continuous days. Sociodemographic data were collected by self-report. Independent associations of sociodemographic correlates with physical activity energy expenditure (PAEE) or moderate-to-vigorous physical activity (MVPA) were analysed in multivariate regression models.

Results

Rural dwellers were significantly more active than their urban counterparts (PAEE: 58.0 vs 42.9 kJ/kg/day; MVPA: 107 vs 62 min/day; MVPA of 150 min/week in >10 min bouts: 62 vs 39%) and less sedentary (923 vs 1026 min/day); p<0.001. There was no significant seasonal difference (dry vs rainy) in activity in urban dwellers whereas in rural dwellers activity was higher during dry seasons compared to rainy seasons (p<0.001). Age, obesity and education showed significant inverse associations with activity. Urban dwellers who considered themselves adequately active were only as active as rural dwellers who thought they were not adequately active.

Conclusions

This is the first study providing data on sociodemographic patterning of objectively-measured physical activity in rural and urban sub-Saharan Africa. Age, urban residence, obesity and higher educational level are important correlates of lower levels of physical activity. These suggest targets for public health interventions to improve physical activity in Cameroon.

Effectiveness of Iyengar yoga in treating spinal (back and neck) pain: A systematic review

Considerable amount of money spent in health care is used for treatments of lifestyle related, chronic health conditions, which come from behaviors that contribute to morbidity and mortality of the population. Back and neck pain are two of the most common musculoskeletal problems in modern society that have significant cost in health care. Yoga, as a branch of complementary alternative medicine, has emerged and is showing to be an effective treatment against nonspecific spinal pain. Recent studies have shown positive outcome of yoga in general on reducing pain and functional disability of the spine. The objective of this study is to conduct a systematic review of the existing research within Iyengar yoga method and its effectiveness on relieving back and neck pain (defined as spinal pain). Database research form the following sources (Cochrane library, NCBI PubMed, the Clinical Trial Registry of the Indian Council of Medical Research, Google Scholar, EMBASE, CINAHL, and PsychINFO) demonstrated inclusion and exclusion criteria that selected only Iyengar yoga interventions, which in turn, identified six randomized control trials dedicated to compare the effectiveness of yoga for back and neck pain versus other care. The difference between the groups on the postintervention pain or functional disability intensity assessment was, in all six studies, favoring the yoga group, which projected a decrease in back and neck pain. Overall six studies with 570 patients showed, that Iyengar yoga is an effective means for both back and neck pain in comparison to control groups. This systematic review found strong evidence for short-term effectiveness, but little evidence for long-term effectiveness of yoga for chronic spine pain in the patient-centered outcomes.

Simple physical performance measures and vascular health in late midlife women: the Study of Women's Health across the nation

BACKGROUND

Physical performance measures have been shown to predict mortality and incident cardiovascular disease (CVD) mainly in elderly populations. We evaluated whether physical performance measures are associated with vascular health indices (carotid intima-media thickness (cIMT), adventitial diameter (cAD) and carotid plaque) in a large sample of multi-ethnic, late midlife women.

METHODS

Participants from the Study of Women's Health Across the Nation free of CVD and who had carotid ultrasound assessed at the 12th annual visit were evaluated. Physical function (PF) measures at visit 12 included: average 40-foot walking speed and average time needed for sit-to-stand assessment.

RESULTS

A total of 1103 women (53.7% White, 30.5% Black, 15.9% Chinese) aged 59.6±2.7years at visit 12, were included. In models adjusted for study site, race, current age, menopausal status and systolic blood pressure, slower walking speed and longer time needed for sit-to-stand were significantly associated with wider cAD, thicker cIMT and a higher probability of a high level of carotid plaque burden (all P-values<0.05). Associations between walking speed and cAD, and between time needed for sit-to-stand and cAD, remained significant (P=0.04) or marginally significant (P=0.07), respectively, after additional adjustment for CVD risk factors, medications and physical activity. However, the associations between PF measures and cIMT and plaque burden were largely explained by traditional CVD risk factors.

CONCLUSIONS

The current study suggests that worse performance in simple objective PF tests may be an early indicator of vascular structural changes that precede vascular disease among women at late midlife.

Dietary patterns and physical inactivity, two contributing factors to the double burden of malnutrition among adults in Burkina Faso, West Africa

A population-based cross-sectional study was carried out in the northern neighbourhoods of Ouagadougou (Burkina Faso), to examine the relationship of nutritional deficiencies and cardiometabolic risk factors (CMRF) with lifestyle in adults. We randomly selected 330 households stratified by income tertile. In each income stratum, 110 individuals aged 25-60 years and having lived in Ouagadougou for at least 6 months were randomly selected. We performed anthropometric, dietary intake and physical activity measurements, and blood sample collection. Cluster analysis of dietary intake identified two dietary patterns: 'urban' (29 % of subjects) and 'traditional' (71 %). The 'urban' cluster exhibited a higher intake of fat and sugar, whereas a higher intake of plant protein, complex carbohydrate and fibre was observed in the 'traditional' pattern. Female sex, low income and lack of education were associated with the 'traditional' cluster, as well as Fe and vitamin A deficiency. CMRF prevalence (abdominal obesity, hypertension, hyperglycaemia, dyslipidaemia) was similar in both clusters. Subjects in the 'traditional' cluster spent more time in physical activity and had less sedentary time than those in the 'urban' cluster. 'Traditional' dietary pattern, low income, female sex and sedentary time were significant contributing factors to the double burden of malnutrition. The rapid nutrition transition is reflected in this co-occurrence of CMRF and nutritional deficiencies. This stresses the need for prevention strategies addressing both ends of the nutrition spectrum.

Calcium handling proteins: structure, function, and modulation by exercise

Heart failure is a serious public health issue with a growing prevalence, and it is related with the aging of the population. Hypertension is identified as the main precursor of left ventricular hypertrophy and therefore can lead to diastolic dysfunction and heart failure. Scientific studies have confirmed the beneficial effects of the physical exercise by reducing the blood pressure and improving the functional status of the heart in hypertension. Several proteins are involved in the mobilization of calcium during the coupling excitation-contraction process in the heart among those are sarcoplasmic reticulum Ca(2+)-ATPase, phospholamban, calsequestrin, sodium-calcium exchanger, L-type calcium's channel, and ryanodine receptors. Our goal is to address the beneficial effects of exercise on the calcium handling proteins in a heart with hypertension.

A labor of love: the influence of cancer caregiving on health behaviors

BACKGROUND

Evidence suggests that emotional distress and objective demands of cancer caregiving are comparable to those of dementia caregiving, yet little research has focused on the physical health of cancer caregivers. Whether the stress leads directly to changes in health or whether the stress leads to changes in health behaviors, which in turn affect health, has not been systematically examined.

OBJECTIVE

The objective of this study was to review the research literature regarding changes in health behaviors associated with caring for an individual with cancer.

METHODS

Literature was reviewed from multiple databases including CINAHL (Cumulative Index to Nursing and Allied Health Literature), CINAHL Plus, PsycNET, PubMed, SCOPUS, EMBASE, and Web of Science. Key words included "health behavior," "health promotion," "caregivers/caregiving," "cancer/oncology," "diet/nutrition," "exercise/physical activity," "stress management," "smoking" and "alcohol." Studies were included if they involved informal adult caregivers and at least 1 behavior associated with a healthy lifestyle. Of the 866 studies identified, 8 met the criteria.

RESULTS

Studies revealed conflicting information, with some suggesting deleterious changes in behaviors, whereas others found the changes protective.

CONCLUSIONS

The lack of uniformity of terminology and conflicting findings make it difficult to conclude the impact of the caregiving experience on the health behaviors of cancer caregivers. Something is placing caregivers at risk for illness and early death, but the mechanisms behind the risk and the role of unhealthy behaviors are not clear.

IMPLICATIONS FOR PRACTICE

At a minimum, cancer caregivers should be screened for behavior changes and disease risk. Developing standardized measures for future research including controlled, longitudinal studies is needed.

The association between physical activity and gastroesophageal cancer: systematic review and meta-analysis

Physical activity may decrease gastroesophageal cancer risk through a reduction of oxidative stress and decreased chronic inflammation, yet few epidemiologic studies have been able to report a clear inverse association between physical activity and gastroesophageal cancer. Because no meta-analysis has investigated the relation of physical activity to gastroesophageal cancer, we conducted a comprehensive systematic review and meta-analysis according to the PRISMA guidelines based on 24 studies with a total of 15,745 cases. When we compared high versus low physical activity levels and summarized associations according to anatomic site and tumor histology, risk reductions were evident for esophageal adenocarcinoma [relative risk (RR) = 0.79, 95% confidence interval (CI) = 0.66-0.94], gastric cardia adenocarcinoma (RR = 0.83, 95% CI = 0.69-0.99) and gastric non-cardia adenocarcinoma (RR = 0.72, 95% CI = 0.62-0.84). The risk reduction for esophageal squamous cell carcinoma (RR = 0.94, 95% CI = 0.41-2.16) became statistically significant (RR = 0.66, 95% CI = 0.46-0.96) after excluding an influential study. The test for heterogeneity by gastroesophageal cancer subtype was statistically non-significant (p-difference = 0.71). The RR of total gastroesophageal cancer for high versus low physical activity was 0.82 (95% CI = 0.74-0.90). A dose-response analysis of frequency of physical activity and total gastroesophageal cancer risk revealed that the greatest risk reduction was achieved among those engaging in moderate to vigorous physical activity five times per week (RR = 0.67, 95% CI = 0.58-0.79). Our results provide support for an inverse relation of physical activity, in particular exercise frequency, to gastroesophageal cancer risk.

Physical activity and cancer-specific mortality in the NIH-AARP Diet and Health Study cohort

Higher physical activity levels have been associated with a lower risk of developing various cancers and all-cancer mortality, but the impact of pre-diagnosis physical activity on cancer-specific death has not been fully characterized. In the prospective National Institutes of Health-AARP Diet and Health Study with 293,511 men and women, we studied prediagnosis moderate to vigorous intensity leisure time physical activity (MVPA) in the past 10 years and cancer-specific mortality. Over a median 12.1 years, we observed 15,001 cancer deaths. Using Cox proportional hazards regression, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for MVPA with cancer mortality overall and by 20 specific cancer sites, adjusting for relevant risk factors. Compared to participants reporting never/rare MVPA, those reporting >7 hr/week MVPA had a lower risk of total cancer mortality (HR = 0.89, 95% CI 0.84-0.94; p-trend <0.001). When analyzed by cancer site-specific deaths, comparing those reporting >7 hr/week of MVPA to those reporting never/rare MVPA, we observed a lower risk of death from colon (HR = 0.70; 95% CI 0.57-0.85; p-trend <0.001), liver (0.71; 0.52-0.98; p-trend = 0.012) and lung cancer (0.84; 0.77-0.92; p-trend <0.001) and a significant p-trend for non-Hodgkins lymphoma (0.80; 0.62-1.04; p-trend = 0.017). An unexpected increased mortality p-trend with increasing MVPA was observed for death from kidney cancer (1.42; 0.98-2.03; p-trend = 0.016). Our findings suggest that higher prediagnosis leisure time physical activity is associated with lower risk of overall cancer mortality and mortality from multiple cancer sites. Future studies should confirm observed associations and further explore timing of physical activity and underlying biological mechanisms.

Dose-response relationship of physical activity to premature and total all-cause and cardiovascular disease mortality in walkers

Purpose

To assess the dose-response relationships between cause-specific mortality and exercise energy expenditure in a prospective epidemiological cohort of walkers.

Methods

The sample consisted of the 8,436 male and 33,586 female participants of the National Walkers' Health Study. Walking energy expenditure was calculated in metabolic equivalents (METs, 1 MET = 3.5 ml O₂/kg/min), which were used to divide the cohort into four exercise categories: category 1 (≤1.07 MET-hours/d), category 2 (1.07 to 1.8 MET-hours/d), category 3 (1.8 to 3.6 MET-hours/d), and category 4 (≥3.6 MET-hours/d). Competing risk regression analyses were use to calculate the risk of mortality for categories 2, 3 and 4 relative to category 1.

Results

22.9% of the subjects were in category 1, 16.1% in category 2, 33.3% in category 3, and 27.7% in category 4. There were 2,448 deaths during the 9.6 average years of follow-up. Total mortality was 11.2% lower in category 2 (P = 0.04), 32.4% lower in category 3 (P<10⁻¹²) and 32.9% lower in category 4 (P = 10⁻¹¹) than in category 1. For underlying causes of death, the respective risk reductions for categories 2, 3 and 4 were 23.6% (P = 0.008), 35.2% (P<10⁻⁵), and 34.9% (P = 0.0001) for cardiovascular disease mortality; 27.8% (P = 0.18), 20.6% (P = 0.07), and 31.4% (P = 0.009) for ischemic heart disease mortality; and 39.4% (P = 0.18), 63.8% (P = 0.005), and 90.6% (P = 0.002) for diabetes mortality when compared to category 1. For all related mortality (i.e., underlying and contributing causes of death combined), the respective risk reductions for categories 2, 3 and 4 were 18.7% (P = 0.22), 42.5% (P = 0.001), and 57.5% (P = 0.0001) for heart failure; 9.4% (P = 0.56), 44.3% (P = 0.0004), and 33.5% (P = 0.02) for hypertensive diseases; 11.5% (P = 0.38), 41.0% (P<10⁻⁴), and 35.5% (P = 0.001) for dysrhythmias: and 23.2% (P = 0.13), 45.8% (P = 0.0002), and 41.1% (P = 0.005) for cerebrovascular diseases when compared to category 1.

Conclusions

There are substantial health benefits to exceeding the current exercise guidelines.

The relationship of walking intensity to total and cause-specific mortality. Results from the National Walkers' Health Study

PURPOSE

Test whether: 1) walking intensity predicts mortality when adjusted for walking energy expenditure, and 2) slow walking pace (≥24-minute mile) identifies subjects at substantially elevated risk for mortality.

METHODS

Hazard ratios from Cox proportional survival analyses of all-cause and cause-specific mortality vs. usual walking pace (min/mile) in 7,374 male and 31,607 female recreational walkers. Survival times were left censored for age at entry into the study. Other causes of death were treated as a competing risk for the analyses of cause-specific mortality. All analyses were adjusted for sex, education, baseline smoking, prior heart attack, aspirin use, diet, BMI, and walking energy expenditure. Deaths within one year of baseline were excluded.

RESULTS

The National Death Index identified 1968 deaths during the average 9.4-year mortality surveillance. Each additional minute per mile in walking pace was associated with an increased risk of mortality due to all causes (1.8% increase, P=10(-5)), cardiovascular diseases (2.4% increase, P=0.001, 637 deaths), ischemic heart disease (2.8% increase, P=0.003, 336 deaths), heart failure (6.5% increase, P=0.001, 36 deaths), hypertensive heart disease (6.2% increase, P=0.01, 31 deaths), diabetes (6.3% increase, P=0.004, 32 deaths), and dementia (6.6% increase, P=0.0004, 44 deaths). Those reporting a pace slower than a 24-minute mile were at increased risk for mortality due to all-causes (44.3% increased risk, P=0.0001), cardiovascular diseases (43.9% increased risk, P=0.03), and dementia (5.0-fold increased risk, P=0.0002) even though they satisfied the current exercise recommendations by walking ≥7.5 metabolic equivalent (MET)-hours per week.

CONCLUSIONS

The risk for mortality: 1) decreases in association with walking intensity, and 2) increases substantially in association for walking pace ≥24 minute mile (equivalent to <400 m during a six-minute walk test) even among subjects who exercise regularly.

High-level activities of daily living and disease-specific mortality during a 12-year follow-up of an octogenarian population

BACKGROUND

Little is known about the relationship between disease-specific mortality and high-level activities of daily living in the elderly. We examined whether mortality is associated with high-level activities of daily living in an octogenarian population.

METHODS

We conducted a population-based cross-sectional and prospective cohort study in 693 older persons aged 80 years and living in Japan's Fukuoka Prefecture. We then evaluated the association between 12-year disease-specific mortality and high-level functional capacity as measured by the Tokyo Metropolitan Institute of Gerontology Index of Competence, which is a standardized multidimensional 13-item instrument; items 1 through 5 are classified as instrumental self-maintenance activity, items 6 through 9 as intellectual activity, items 10 through 13 as social roles activity, and all 13 items together yield total functional capacity.

RESULTS

By the 12-year follow-up of the 693 participants, 413 had died, 242 survived, and 38 were unable to be located. Of the 413 who died, 105 died of cardiovascular disease, 73 of respiratory tract disease, 71 of cancer, and 39 of senility. Of the other 125 deaths, 59 were due to other diseases, and the cause of death for 66 participants is not known. The hazard ratio (HR) for all-cause mortality, adjusted for confounding factors with multivariate Cox analyses, fell by 6% (HR 0.937, 95% confidence interval [CI] 0.899-0.978, P = 0.003) with each one-point increase in participants' scores on the Tokyo Metropolitan Institute of Gerontology Index of total functional capacity. With one-point increases in instrumental self-maintenance activity and in intellectual activity, the HRs for all-cause mortality decreased by 14% (HR 0.856, 95% CI 0.787-0.930, P = 0.000) and 12% (HR 0.884, 95% CI 0.794-0.983, P = 0.023), respectively. Respiratory mortality with HR adjustment fell by 11% (HR 0.887, 95% CI 0.804-0.978, P = 0.016) and 24% (HR 0.760, 95% CI 0.627-0.922, P = 0.005) with one-point increases in the scores of total functional capacity and instrumental self-maintenance activity, respectively. Similarly, mortality due to senility fell by 16% (HR 0.838, 95% CI 0.743-0.946, P = 0.004), 29% (HR 0.707, 95% CI 0.564-0.886, P = 0.003), and 29% (HR 0.710, 95% CI 0.522-0.966, P = 0.029) with one-point increases in the scores of total functional capacity, instrumental self-maintenance activity, and intellectual activity, respectively.

CONCLUSION

These findings suggest that high-level activities of daily living may be an independent predictor of mortality due to all causes, respiratory disease and senility in older persons.

Physical activity, cardiorespiratory fitness, and exercise training in primary and secondary coronary prevention

Substantial data have established that higher levels of physical activity (PA), participating in exercise training (ET), and higher overall cardiorespiratory fitness (CRF) provide considerable protection in the primary and secondary prevention of coronary heart disease (CHD). This review surveys data from epidemiological and prospective ET studies supporting the favorable impact of PA, ET, and CRF in primary CHD prevention. Clearly, cardiac rehabilitation and ET (CRET) programs have been underutilized for patients with CHD, particularly considering the effect of CRET on CHD risk factors, including CRF, obesity indices, fat distribution, plasma lipids, inflammation, and psychological distress, as well as overall morbidity and mortality. These data strongly support the routine referral of patients with CHD to CRET programs and that patients should be vigorously encouraged to attend CRET following major CHD events.

Frequency of yoga practice predicts health: results of a national survey of yoga practitioners

Background. Yoga shows promise as a therapeutic intervention, but relationships between yoga practice and health are underexplored. Purpose. To examine the relationship between yoga practice and health (subjective well-being, diet, BMI, smoking, alcohol/caffeine consumption, sleep, fatigue, social support, mindfulness, and physical activity). Methods. Cross-sectional, anonymous internet surveys distributed to 4307 randomly selected from 18,160 individuals at 15 US Iyengar yoga studios; 1045 (24.3%) surveys completed. Results. Mean age 51.7 (± 11.7) years; 84.2% female. Frequency of home practice favorably predicted (P < .001): mindfulness, subjective well-being, BMI, fruit and vegetable consumption, vegetarian status, sleep, and fatigue. Each component of yoga practice (different categories of physical poses, breath work, meditation, philosophy study) predicted at least 1 health outcome (P < .05). Conclusions. Home practice of yoga predicted health better than years of practice or class frequency. Different physical poses and yoga techniques may have unique health benefits.

Effect of intensity and type of physical activity on mortality: results from the Whitehall II cohort study

OBJECTIVES

We examined the association of intensity and type of physical activity with mortality.

METHODS

We assessed the duration of physical activity by intensity level and type in 7456 men and women from the Whitehall II Study by questionnaire in 1997-1999 (mean ±SD age = 55.9 ± 6.0 years) and 5 years later. All-cause mortality was assessed until April 2009.

RESULTS

A total of 317 participants died during the mean follow-up of 9.6 years (SD = 2.7). Reporting at least 1 hour per week of moderate activity was associated with a 33% (95% confidence interval [CI] = 14%, 45%) lower risk of mortality compared with less than 1 hour. For all physical activity types examined, except housework, a duration of physical activity greater than 0 (≥ 3.5 hours for walking) was associated with lower mortality in age-adjusted analyses, but only the associations with sports (hazard ratio [HR] = 0.71; 95% CI = 0.56, 0.91) and do-it-yourself activity (HR = 0.68; 95% CI = 0.53, 0.98) remained in fully adjusted analyses.

CONCLUSIONS

It is important to consider both intensity and type of physical activity when examining associations with mortality.

Long-term course of pain in breast cancer survivors: a 4-year longitudinal study

After successful treatment of early breast cancer, many women still report pain symptoms, and attribute them to the previous illness or its treatment. However, knowledge about the long-term course of pain in breast cancer is limited. Baseline assessment included 3,088 women who received a breast cancer diagnosis on average 2 years prior to enrollment, and who completed typical medical treatments. After 4 years, a subsample of 2,160 recurrence-free women (70%) was re-assessed. The major outcome variable was the composite index for general pain symptoms. Over the 4-year course, a slight but significant increase in pain was reported. If only medical variables were examined, a triple interaction between surgery type, breast cancer stage, and time indicated that pain scores increased in most subgroups, while they decreased in stage II women after mastectomy and stage III women after lumpectomy. Using a regression analytical approach, psychological and other variables added significantly to the prediction of pain persistence. Regression analysis revealed that pain symptoms increased in those women taking tamoxifen at baseline, in those reporting depression at baseline or stressful life events during the first 12 months after enrollment. Exercise at baseline had a beneficial effect on pain recovery. The persistence or increase of pain symptoms in women surviving breast cancer is associated with some medical factors (surgery type, tamoxifen use), but also with psychological factors. Pain should be a standard outcome variable in the evaluation of cancer treatment programs.

Physical activity moderates effects of stressor-induced rumination on cortisol reactivity

OBJECTIVE

Physically active individuals have lower rates of morbidity and mortality, and recent evidence indicates that physical activity may be particularly beneficial to those experiencing chronic stress. The tendency to ruminate increases and prolongs physiological stress responses, including hypothalamic-pituitary-adrenal (HPA) axis responses as indexed by cortisol reactivity to stressful experiences. We examined the association between ruminating in response to a laboratory stressor task and HPA axis reactivity and recovery and examined whether a physically active life-style moderates the associations between rumination and cortisol output trajectories.

METHODS

Forty-six postmenopausal women underwent the Trier Social Stress Test, whereas salivary cortisol was repeatedly measured. Twenty-five minutes after the end of the stressor, participants reported level of rumination in response to the stress.

RESULTS

Findings indicate that physical activity moderated the initial rate (B = -0.10, standard error = 0.04, p < .05) and curvature (B = -0.03, standard error = 0.01, p = .06) of the relationship between rumination and log-transformed cortisol trajectory. Among sedentary participants, those who responded to the stressor with higher levels of rumination had a more rapid initial increase in cortisol level (0.26 versus 0.21, p < .001), a later peak in cortisol reactivity (56 versus 39 minutes), and a delayed recovery from stress (curvature: -0.07 versus -0.08, p < .001) compared with those with lower levels of rumination. In active participants, cortisol trajectories were equivalent, regardless of the level of rumination.

CONCLUSIONS

In sum, individuals who maintain a physically active life-style may be protected against the effects of rumination on HPA axis reactivity to and recovery from acute stress.

Modifiable risk factors for prostate cancer mortality in London: forty years of follow-up in the Whitehall study

BACKGROUND

The determinants of prostate cancer--aside from established but non-modifiable risk factors of increased age, black ethnicity, and a positive family history--are poorly understood.

METHODS

We examined the association of a series of baseline socioeconomic, behavioral, and metabolic characteristics with the risk of prostate cancer mortality in a 40-year follow-up of study members from the original Whitehall cohort study. During this period there were 578 prostate cancer deaths in 17,934 men.

RESULTS

After adjustment for a series of baseline covariates, results from proportional hazards regression analyses indicated that marital status (hazard ratio; 95% confidence interval: widowed/divorced vs. married: 1.44; 0.95, 2.18), raised blood cholesterol (tertile 3 vs. 1: 1.35; 1.11, 1.65), and increased physical stature (tertile 3 vs. 1: 1.37; 1.09, 1.74) were associated with death from prostate cancer, although statistical significance at conventional levels was not apparent in all analyses. There was no evidence that physical activity, smoking habit, socio-economic status, component of either blood pressure or diabetes predicted the risk of death from this malignancy herein.

CONCLUSIONS

In the present study, there was a suggestion that marital status, blood cholesterol, and height were risk indices for death from prostate cancer.

Forced expiratory volume predicts all-cause and cancer mortality in Mumbai, India: results from a population-based cohort study

BACKGROUND

Reduction in pulmonary function, as estimated by forced expiratory volume in 1 s (FEV(1)), has been found to predict all-cause mortality in developed-country populations. This study was designed to examine the association between FEV(1) and mortality in an urban developing-country population.

METHODS

Data from the large, well-characterized Mumbai Cohort Study (Maharashtra, India) were used to compute hazard ratios (HRs; deaths/100-ml FEV(1)) and 95% confidence intervals (CIs) from Cox proportional hazards regression models in which age, tobacco use, education, height and relative body weight were controlled.

RESULTS

A total of 13,261 deaths occurred in this cohort of 148,173 individuals. After controlling for important covariates, there was a 1.7% reduction in risk of overall death in women for each 100-ml increment in FEV(1) (HR = 0.983; 95% CI = 0.980-0.986) and a 1.5% reduction in men (HR = 0.985; 95% CI = 0.984-0.986). There was a 1.6% reduction in cancer deaths in women (HR = 0.984; 95% CI = 0.973-0.996) and a 0.8% reduction in men (HR = 0.992; 95% CI = 0.987-0.997). The largest reductions in women were observed in tuberculosis deaths (3.7%/100-ml increment in FEV(1)), and in men in respiratory system deaths (3.2%).

CONCLUSIONS

In a densely populated urban Indian population, FEV(1) predicted overall and cancer mortality. Effects were larger in women and were not attenuated by exclusion of smokers or restricting analyses to subjects dying >2 years from recruitment. Because FEV(1) may be affected by air pollution, which is worsening in urban areas of most developing countries, further research is recommended to deepen understanding of these factors in relation to mortality.

Epidemiological aspects of gastric adenocarcinoma: are predictive diagnostics and targeted preventive measures possible?

The incidence of gastric cancer has witnessed major changes over the past decades. Until recently, gastric cancer was a common malignancy in most countries. A striking decline in incidence in most Western populations has occurred since the 1970s, and elucidating the detailed causes for this trend can potentially be of great value for targeted preventive measures. Furthermore, it can add to the understanding of malignant disease and prevention in general. Moreover, the absolute number of cases worldwide is predicted to increase during many years to come. Gastric cancer is typically diagnosed at an advanced stage in symptomatic patients, and there are often no effective curative or palliative or therapeutic options. This fact highlights the need for research aiming to increase our understanding of the etiology of this cancer, facilitating the design of successful targeted preventive strategies for different populations. The future outlook in terms of decreasing gastric cancer deaths would be to identify such intelligent diagnostic tools. In this article, we present a summary of the epidemiology of gastric cancer, with special focus on its etiology.

Influence of cardiorespiratory fitness on lung cancer mortality

PURPOSE

Previous studies have suggested that higher levels of physical activity may lower lung cancer risk; however, few prospective studies have evaluated lung cancer mortality in relation to cardiorespiratory fitness (CRF), an objective marker of recent physical activity habits.

METHODS

Thirty-eight thousand men, aged 20-84 yr, without history of cancer, received a preventive medical examination at the Cooper Clinic in Dallas, Texas, between 1974 and 2002. CRF was quantified as maximal treadmill exercise test duration and was grouped for analysis as low (lowest 20% of exercise duration), moderate (middle 40%), and high (upper 40%).

RESULTS

A total of 232 lung cancer deaths occurred during follow-up (mean = 17 yr). After adjustment for age, examination year, body mass index, smoking, drinking, physical activity, and family history of cancer, hazard ratios (95% confidence intervals) for lung cancer deaths across low, moderate, and high CRF categories were 1.0, 0.48 (0.35-0.67), and 0.43 (0.28-0.65), respectively. There was an inverse association between CRF and lung cancer mortality in former (P for trend = 0.005) and current smokers (P for trend < 0.001) but not in never smokers (trend P = 0.14). Joint analysis of smoking and fitness status revealed a significant 12-fold higher risk of death in current smokers (hazard ratio = 11.9, 95% confidence interval = 6.0-23.6) with low CRF as compared with never smokers who had high CRF.

CONCLUSIONS

Although the potential for some residual confounding by smoking could not be eliminated, these data suggest that CRF is inversely associated with lung cancer mortality in men. Continued study of CRF in relation to lung cancer, particularly among smokers, may further our understanding of disease etiology and reveal additional strategies for reducing its burden.

The influence of multiple indices of socioeconomic disadvantage across the adult life course on the metabolic syndrome: the Vietnam Experience Study

Few studies have explored the relationship between individual and combined multiple indicators of socioeconomic status across the life course and the metabolic syndrome, or attempted to understand the mechanisms underlying any associations. The present study examined the associations between 4 indicators of socioeconomic status, individually and in combination, and metabolic syndrome risk in a study of male US veterans and examined the influence of health behaviors, intelligence, and psychologic distress on these associations. Participants (N = 4253) were drawn from the Vietnam Experience Study. From military service files, telephone interviews, and a medical examination, occupational, sociodemographic, health behavior, intelligence, psychologic, and health data were collected. The 4 indices of socioeconomic status were as follows: education achieved, early adulthood income, household income in midlife, and occupational prestige in midlife. Metabolic syndrome was diagnosed from the following: body mass index, fasting blood glucose or a diagnosis of diabetes, blood pressure-a diagnosis of hypertension or taking antihypertensives, high-density lipoprotein cholesterol, and triglyceride levels. In models that adjusted for age, men in the lower 2 groups on the combined measure of socioeconomic status experienced a higher risk of metabolic syndrome. This association was accounted for mainly by education achieved, household income in midlife, and occupational prestige in midlife. Intelligence appeared to explain much of this association. Combined socioeconomic status measures across the life course were related to metabolic syndrome but in a threshold rather than dose-response manner. Intelligence appeared to mediate this relationship.

Walking pace, leisure time physical activity, and resting heart rate in relation to disease-specific mortality in London: 40 years follow-up of the original Whitehall study. An update of our work with professor Jerry N. Morris (1910-2009)

PURPOSE

To examine the association of leisure time physical activity, walking pace and resting heart rate with disease-specific mortality in a prospective cohort study by reporting updated analyses of an earlier report we produced with the British epidemiologist, Jerry N. Morris (1910-2009).

METHODS

In the original Whitehall study, 19,019 male, nonindustrial, London-based government employees, aged from 40 to 69 years in 1967 and 1970, participated in a medical examination during which data on leisure time physical activity (N = 6715), self-rated walking pace (N = 6729), and resting heart rate (N = 1183) were collected. Cox proportional hazards analyses were used to estimate hazard ratios for the relation between these exposures and disease-specific mortality.

RESULTS

In models adjusted for a range of covariates including socioeconomic status, smoking, and obesity, high resting heart rate was associated with a modestly elevated rate of mortality from all causes (hazard ratio; 95% confidence interval: tertile 3 vs. tertile 1: 1.17; 0.99, 1.37 p[trend]: 0.07) and respiratory disease (1.69; 1.04, 2.76 p[trend]: 0.03). Of the two markers of physical activity, walking pace was inversely related to mortality ascribed to all causes (slow vs. high walking pace 1.71; 1.53, 1.91 p[trend]: <0.001]), coronary heart disease (2.03; 1.68, 2.47 p[trend]: <0.001), and total cancers (1.25; 0.98, 1.59 p[trend]: 0.04). The corresponding associations for leisure time activity were typically weaker. For other mortality endpoints-respiratory disease (walking pace: 1.96; 1.48, 2.60 p[trend]: <0.001]), hematopoietic cancer (walking pace: 1.36; 0.52, 3.51 p[trend]: 0.03), stomach cancer (inactive versus active leisure time: 1.53; 0.88, 2.64 p[trend]: 0.04), and rectal cancer (walking pace: 4.85; 1.70, 13.8 p[trend]: 0.007)-individual activity indices revealed effects, but not both.

CONCLUSIONS

Higher levels of physical activity indexed by the various markers herein appeared to confer protection against a range of mortality outcomes.

A systematic review of the evidence for Canada's Physical Activity Guidelines for Adults

This systematic review examines critically the scientific basis for Canada's Physical Activity Guide for Healthy Active Living for adults. Particular reference is given to the dose-response relationship between physical activity and premature all-cause mortality and seven chronic diseases (cardiovascular disease, stroke, hypertension, colon cancer, breast cancer, type 2 diabetes (diabetes mellitus) and osteoporosis). The strength of the relationship between physical activity and specific health outcomes is evaluated critically. Literature was obtained through searching electronic databases (e.g., MEDLINE, EMBASE), cross-referencing, and through the authors' knowledge of the area. For inclusion in our systematic review articles must have at least 3 levels of physical activity and the concomitant risk for each chronic disease. The quality of included studies was appraised using a modified Downs and Black tool. Through this search we identified a total of 254 articles that met the eligibility criteria related to premature all-cause mortality (N = 70), cardiovascular disease (N = 49), stroke (N = 25), hypertension (N = 12), colon cancer (N = 33), breast cancer (N = 43), type 2 diabetes (N = 20), and osteoporosis (N = 2). Overall, the current literature supports clearly the dose-response relationship between physical activity and the seven chronic conditions identified. Moreover, higher levels of physical activity reduce the risk for premature all-cause mortality. The current Canadian guidelines appear to be appropriate to reduce the risk for the seven chronic conditions identified above and all-cause mortality.

Influence of cardiorespiratory fitness on lung cancer mortality

PURPOSE

Previous studies have suggested that higher levels of physical activity may lower lung cancer risk; however, few prospective studies have evaluated lung cancer mortality in relation to cardiorespiratory fitness (CRF), an objective marker of recent physical activity habits.

METHODS

Thirty-eight thousand men, aged 20-84 yr, without history of cancer, received a preventive medical examination at the Cooper Clinic in Dallas, Texas, between 1974 and 2002. CRF was quantified as maximal treadmill exercise test duration and was grouped for analysis as low (lowest 20% of exercise duration), moderate (middle 40%), and high (upper 40%).

RESULTS

A total of 232 lung cancer deaths occurred during follow-up (mean = 17 yr). After adjustment for age, examination year, body mass index, smoking, drinking, physical activity, and family history of cancer, hazard ratios (95% confidence intervals) for lung cancer deaths across low, moderate, and high CRF categories were 1.0, 0.48 (0.35-0.67), and 0.43 (0.28-0.65), respectively. There was an inverse association between CRF and lung cancer mortality in former (P for trend = 0.005) and current smokers (P for trend < 0.001) but not in never smokers (trend P = 0.14). Joint analysis of smoking and fitness status revealed a significant 12-fold higher risk of death in current smokers (hazard ratio = 11.9, 95% confidence interval = 6.0-23.6) with low CRF as compared with never smokers who had high CRF.

CONCLUSIONS

Although the potential for some residual confounding by smoking could not be eliminated, these data suggest that CRF is inversely associated with lung cancer mortality in men. Continued study of CRF in relation to lung cancer, particularly among smokers, may further our understanding of disease etiology and reveal additional strategies for reducing its burden.

Walking speed and subclinical atherosclerosis in healthy older adults: the Whitehall II study

Objective

Extended walking speed is a predictor of incident cardiovascular disease (CVD) in older individuals, but the ability of an objective short-distance walking speed test to stratify the severity of preclinical conditions remains unclear. This study examined whether performance in an 8-ft walking speed test is associated with metabolic risk factors and subclinical atherosclerosis.

Design

Cross-sectional.

Setting

Epidemiological cohort.

Participants

530 adults (aged 63±6 years, 50.3% male) from the Whitehall II cohort study with no known history or objective signs of CVD.

Main outcome

Electron beam computed tomography and ultrasound was used to assess the presence and extent of coronary artery calcification (CAC) and carotid intima-media thickness (IMT), respectively.

Results

High levels of CAC (Agatston score >100) were detected in 24% of the sample; the mean IMT was 0.75 mm (SD 0.15). Participants with no detectable CAC completed the walking course 0.16 s (95% CI 0.04 to 0.28) faster than those with CAC ≥400. Objectively assessed, but not self-reported, faster walking speed was associated with a lower risk of high CAC (odds ratio 0.62, 95% CI 0.40 to 0.96) and lower IMT (β=−0.04, 95% CI −0.01 to −0.07 mm) in comparison with the slowest walkers (bottom third), after adjusting for conventional risk factors. Faster walking speed was also associated with lower adiposity, C-reactive protein and low-density lipoprotein cholesterol.

Conclusions

Short-distance walking speed is associated with metabolic risk and subclinical atherosclerosis in older adults without overt CVD. These data suggest that a non-aerobically challenging walking test reflects the presence of underlying vascular disease.

A systematic review of the association between physical activity and colorectal cancer risk

This review evaluated the strength of the evidence for a causal relationship between physical activity (PA) and colorectal cancer (CRC). A systematic review of databases through February 2008 was conducted to identify studies that assessed the association between total or recreational PA and incidence or mortality of CRC (including CRC, rectal cancer, colon cancer, and proximal or distal colon cancer). Studies were evaluated for significant associations between PA and risk of CRC endpoints and for evidence of dose-response relationships in the highest quality studies. Twenty cohort studies were evaluated; 11 were high-quality. Fifty percent of all studies and 64% of highest quality studies reported at least one significant association between PA and risk of a CRC endpoint (P<0.05). However, only 28% of all analyses (31% of analyses of highest quality studies) were significant (P<0.05). Only 40% of analyses of highest quality studies resulted in a significant P for trend (P<0.05); however, a non-significant inverse linear association between PA and colon cancer risk was apparent. Heterogeneity in the evidence from all studies and from the highest quality studies was evident. Evidence from cohort studies is not sufficient to claim a convincing relationship exists between PA and CRC risk.

Does IQ explain socio-economic differentials in total and cardiovascular disease mortality? Comparison with the explanatory power of traditional cardiovascular disease risk factors in the Vietnam Experience Study

AIMS

The aim of this study was to examine the explanatory power of intelligence (IQ) compared with traditional cardiovascular disease (CVD) risk factors in the relationship of socio-economic disadvantage with total and CVD mortality, that is the extent to which IQ may account for the variance in this well-documented association.

METHODS AND RESULTS

Cohort study of 4289 US male former military personnel with data on four widely used markers of socio-economic position (early adulthood and current income, occupational prestige, and education), IQ test scores (early adulthood and middle-age), a range of nine established CVD risk factors (systolic and diastolic blood pressure, total blood cholesterol, HDL cholesterol, body mass index, smoking, blood glucose, resting heart rate, and forced expiratory volume in 1 s), and later mortality. We used the relative index of inequality (RII) to quantify the relation between each index of socio-economic position and mortality. Fifteen years of mortality surveillance gave rise to 237 deaths (62 from CVD and 175 from 'other' causes). In age-adjusted analyses, as expected, each of the four indices of socio-economic position was inversely associated with total, CVD, and 'other' causes of mortality, such that elevated rates were evident in the most socio-economically disadvantaged men. When IQ in middle-age was introduced to the age-adjusted model, there was marked attenuation in the RII across the socio-economic predictors for total mortality (average 50% attenuation in RII), CVD (55%), and 'other' causes of death (49%). When the nine traditional risk factors were added to the age-adjusted model, the comparable reduction in RII was less marked than that seen after IQ adjustment: all-causes (40%), CVD (40%), and 'other' mortality (43%). Adding IQ to the latter model resulted in marked, additional explanatory power for all outcomes in comparison to the age-adjusted analyses: all-causes (63%), CVD (63%), and 'other' mortality (65%). When we utilized IQ in early adulthood rather than middle-age as an explanatory variable, the attenuating effect on the socio-economic gradient was less pronounced although the same pattern was still present.

CONCLUSION

In the present analyses of socio-economic gradients in total and CVD mortality, IQ appeared to offer greater explanatory power than that apparent for traditional CVD risk factors.

The effects of gender and age on health related behaviors

Background

Lifestyle-related diseases, including diabetes, cardiovascular disease, and some cancers represent the greatest global health threat. Greater insight into health needs and beliefs, using broad community samples, is vital to reduce the burden of chronic disease. This study aimed to investigate gender, age, screening practices, health beliefs, and perceived future health needs for healthy ageing.

Methods

Random probability sampling using self-completion surveys in 1456 adults residing in Australia.

Results

Screening behaviors were associated with gender and age. Men and women >51 years were more likely (27%) to have screening health checks than those <50 years (2%). Factors nominated to influence health were lifestyle (92%), relationships (82%), and environment (80%). Women were more likely to nominate preparedness to have an annual health check, willingness to seek advice from their medical practitioner and to attend education sessions. Numerous health fears were associated with ageing, however participants were more likely to have a financial (72%) rather than a health plan (42%). More women and participants >51 years wanted information regarding illness prevention than men or those aged <30 years.

Conclusion

Age and gender are associated with health related behaviors. Optimal health is perceived as a priority, yet often this perception is not translated into preventative action. These findings will inform future research and policy makers as we strive towards a healthier ageing society and the prevention of chronic disease.

Measures of physical activity and their correlates: the Swedish National March Cohort

We compared the results of self-estimates of physical activity obtained with a novel instrument (the Energy Expenditure Questionnaire, EEQ) to those obtained from questions typically asked in epidemiological investigations (reference method) in a cohort of 42,150 Swedish men and women, aged 18-94. In the EEQ, participants were asked to report total physical activity by estimating the total time during a typical day and night spent on different physical activity intensity levels from the lowest (corresponding to lying in bed, 0.9 Metabolic Energy Turnover; MET) to the highest, (exceeding the intensity of to shovelling snow by hand, i.e., >6 MET). As a comparison, they also estimated hours per week devoted to household chores, commuting and leisure time physical activities classified as; light, moderate and heavy. The average physical activity estimated with the EEQ was 1.36 MET or 32.6 METh/day or 2,341 kcal/day. In comparison, physical activity estimated with the reference method represented no more than 17% of this amount. The Spearman's correlation coefficient between the two measures was 0.26. Using EEQ, men reported significantly more physical activity than women (mean = 36.3 vs. 30.6 METh/day). Body mass index (BMI) > or = 25, education > or = 12 years, and age > or = 60 years were significantly associated with lower physical activity. Questions focusing on leisure time exercise and a few other selected activities provide estimates of activity that correlate poorly with self-reported total energy output from all physical activity and inactivity. Investigators need to be more explicit about which component of activity they investigate.

Prospective study of physical activity and lung cancer by histologic type in current, former, and never smokers

Increased physical activity has been associated with decreased lung cancer risk. However, no previous investigation has examined physical activity in relation to lung cancer histologic types by smoking status. The authors investigated these relations in the National Institutes of Health-AARP Diet and Health Study among 501,148 men and women aged 50-71 years at baseline in 1995-1996. During follow-up to 2003, 6,745 lung carcinomas occurred (14.8% small cell, 40.3% adenocarcinoma, 19.7% squamous cell, 6.1% undifferentiated large cell, 7.2% non-small cell not otherwise specified, and 11.8% carcinoma not otherwise specified). Among former smokers, the multivariate relative risks of small cell, adenocarcinoma, squamous cell, and undifferentiated large cell carcinomas comparing the highest with the lowest activity level (> or =5 times/week vs. inactive) were 0.93 (95% confidence interval (CI): 0.67, 1.28), 0.79 (95% CI: 0.67, 0.94), 0.73 (95% CI: 0.57, 0.93), and 0.61 (95% CI: 0.38, 0.98), respectively. Among current smokers, corresponding values were 0.77 (95% CI: 0.58, 1.02), 0.76 (95% CI: 0.61, 0.95), 0.85 (95% CI: 0.65, 1.11), and 1.10 (95% CI: 0.69, 1.78). In contrast, physical activity was unrelated to lung carcinoma among never smokers (P(interaction) between physical activity and smoking for total lung carcinomas = 0.002). The inverse findings among former and current smokers in combination with the null results for physical activity among never smokers may point toward residual confounding by cigarette smoking as an explanation for the relations observed.

Walking for prevention of cardiovascular disease in men and women: a systematic review of observational studies

In this systematic review, walking (a generally accessible activity for a largely sedentary population) was assessed as a preventive risk factor for development of fatal and non-fatal cardiovascular disease (CVD). PubMed, CINHAL and reference list searches identified 21 peer-reviewed publications examining walking in relation to CVD; studies assessing active transportation were excluded. Generally, there were dose-dependent reductions in CVD risk with higher walking duration, distance, energy expenditure and pace. Associations appeared to be stronger for ischaemic stroke than other CVD outcomes such as coronary heart disease or haemorrhagic stroke. Adjustment for clinical CVD risk factors, obesity or other types of physical activity generally attenuated but did not eliminate associations. Because functional status may be an important determinant of walking behaviour in adults, potential bias due to pre-existing illness is of concern in all studies reviewed, particularly in case-control studies which ascertain walking retrospectively and yielded the strongest associations. Study findings were consistent with current physical activity recommendations, but there is a need for improvements in measurement of walking and other CVD risk factors, more thorough control for pre-existing illness, examination of mediating or moderating conditions such as obesity and other analytical issues.

Physical activity and esophageal and gastric carcinoma in a large prospective study

BACKGROUND

Few studies have investigated the relationship of physical activity to esophageal and gastric carcinoma according to histology and anatomic site.

METHODS

This study prospectively investigated the association between physical activity and esophageal and gastric carcinoma in a cohort of 487,732 U.S. men and women, followed from 1995-1996 to December 31, 2003. All analyses were performed in 2007-2008.

RESULTS

During 8 years of follow-up study, 523 cases of esophageal carcinoma (149 squamous cell and 374 adenocarcinoma) and 642 cases of gastric carcinoma (313 cardia and 329 noncardia) were documented. Physical activity was associated with reduced risk of esophageal and gastric adenocarcinomas but was unrelated to esophageal squamous cell carcinoma. The inverse association with physical activity was strongest for gastric noncardia adenocarcinoma (multivariate relative risk [RR] for highest versus lowest physical activity level=0.62, 95% CI=0.44, 0.87). Relationships were weaker but evident for gastric cardia adenocarcinoma (RR=0.83; 95% CI=0.58, 1.19) and esophageal adenocarcinoma (RR=0.75; 95% CI=0.53, 1.06). No significant relationship with physical activity was observed for esophageal squamous cell carcinoma (RR=1.05; 95% CI=0.64, 1.74). Exclusion of cases diagnosed during the first 2 follow-up years did not change those estimates, indicating that the findings are not due to decreased activity levels among participants with undiagnosed cancer at entry.

CONCLUSIONS

Physical activity may play a role in the prevention of upper gastrointestinal tract adenocarcinomas. No association was seen between physical activity and esophageal squamous cell carcinoma.

Risk factors for pancreatic cancer mortality: extended follow-up of the original Whitehall Study

Given the well-established links between diabetes and elevated rates of pancreatic cancer, there are reasons to anticipate that other markers of metabolic abnormality (increased body mass index, plasma cholesterol, and blood pressure) and their correlates (physical activity and socioeconomic status) may also confer increased risk. However, to date, the results of a series of population-based cohort studies are inconclusive. We examined these associations in the original Whitehall cohort study of 17,898 men. A maximum of 38 years of follow-up gave rise to 163 deaths due to carcinoma of the pancreas. Although Poisson regression analyses confirmed established risk factor-disease associations for increasing age, smoking, and type II diabetes, there was essentially no evidence that body mass index (rate ratio, 1.01; 95% confidence interval per 1 SD increase, 0.86-1.18), plasma cholesterol (0.91; 0.78-1.07), diastolic blood pressure (0.93; 0.78-1.09), systolic blood pressure (0.98; 0.83-1.15), physical activity (sedentary versus high: 1.37; 0.89-2.12), or socioeconomic status [clerical (low) versus professional/executive, 0.95; 0.59-1.51] offered any predictive value for pancreatic cancer mortality. These results were unchanged following control for a range of covariates.

Physical activity and pancreatic cancer risk: a systematic review

BACKGROUND

Physical activity has been associated with a lower risk for pancreatic cancer in several studies, but the overall epidemiologic evidence is not consistent. We therefore did a systematic review to evaluate the association between physical activity and pancreatic cancer risk.

METHODS

We searched MEDLINE and EMBASE through April 2008 and examined the reference lists of the retrieved articles. We excluded studies that relied on job titles as surrogate measures for physical activity. We used a random-effects model to pool study-specific risk estimates comparing the highest versus the lowest category of physical activity.

RESULTS

Total physical activity (occupational and leisure time) was not significantly associated with risk for pancreatic cancer [4 prospective studies; summary relative risk, 0.76, 95% confidence interval (95% CI), 0.53-1.09]. A decreased risk for pancreatic cancer was observed for occupational physical activity (3 prospective studies; relative risk, 0.75; 95% CI, 0.58-0.96) but not for leisure-time physical activity (14 prospective studies; relative risk, 0.94; 95% CI, 0.83-1.05). No association was found with light physical activity (2 prospective studies; relative risk, 1.01; 95% CI, 0.77-1.34), moderate physical activity (6 prospective studies; relative risk, 0.83; 95% CI, 0.58-1.18), or vigorous physical activity (7 prospective studies; relative risk, 0.94; 95% CI, 0.80-1.12).

CONCLUSIONS

This systematic review does not provide strong evidence for an association between physical activity and risk for pancreatic cancer.

Effect of exposure to natural environment on health inequalities: an observational population study

BACKGROUND

Studies have shown that exposure to the natural environment, or so-called green space, has an independent effect on health and health-related behaviours. We postulated that income-related inequality in health would be less pronounced in populations with greater exposure to green space, since access to such areas can modify pathways through which low socioeconomic position can lead to disease.

METHODS

We classified the population of England at younger than retirement age (n=40 813 236) into groups on the basis of income deprivation and exposure to green space. We obtained individual mortality records (n=366 348) to establish whether the association between income deprivation, all-cause mortality, and cause-specific mortality (circulatory disease, lung cancer, and intentional self-harm) in 2001-05, varied by exposure to green space measured in 2001, with control for potential confounding factors. We used stratified models to identify the nature of this variation.

FINDINGS

The association between income deprivation and mortality differed significantly across the groups of exposure to green space for mortality from all causes (p<0.0001) and circulatory disease (p=0.0212), but not from lung cancer or intentional self-harm. Health inequalities related to income deprivation in all-cause mortality and mortality from circulatory diseases were lower in populations living in the greenest areas. The incidence rate ratio (IRR) for all-cause mortality for the most income deprived quartile compared with the least deprived was 1.93 (95% CI 1.86-2.01) in the least green areas, whereas it was 1.43 (1.34-1.53) in the most green. For circulatory diseases, the IRR was 2.19 (2.04-2.34) in the least green areas and 1.54 (1.38-1.73) in the most green. There was no effect for causes of death unlikely to be affected by green space, such as lung cancer and intentional self-harm.

INTERPRETATION

Populations that are exposed to the greenest environments also have lowest levels of health inequality related to income deprivation. Physical environments that promote good health might be important to reduce socioeconomic health inequalities.

IQ in late adolescence/early adulthood, risk factors in middle age and later all-cause mortality in men: the Vietnam Experience Study

OBJECTIVE

To examine the role of potential mediating factors in explaining the IQ-mortality relation.

DESIGN, SETTING AND PARTICIPANTS

A total of 4316 male former Vietnam-era US army personnel with IQ test results at entry into the service in late adolescence/early adulthood in the 1960/1970s (mean age at entry 20.4 years) participated in a telephone survey and medical examination in middle age (mean age 38.3 years) in 1985-6. They were then followed up for mortality experience for 15 years.

MAIN RESULTS

In age-adjusted analyses, higher IQ scores were associated with reduced rates of total mortality (hazard ratio (HR)(per SD increase in IQ) 0.71; 95% CI 0.63 to 0.81). This relation did not appear to be heavily confounded by early socioeconomic position or ethnicity. The impact of adjusting for some potentially mediating risk indices measured in middle age on the IQ-mortality relation (marital status, alcohol consumption, systolic and diastolic blood pressure, pulse rate, blood glucose, body mass index, psychiatric and somatic illness at medical examination) was negligible (<10% attenuation in risk). Controlling for others (cigarette smoking, lung function) had a modest impact (10-17%). Education (0.79; 0.69 to 0.92), occupational prestige (0.77; 0.68 to 0.88) and income (0.86; 0.75 to 0.98) yielded the greatest attenuation in the IQ-mortality gradient (21-52%); after their collective adjustment, the IQ-mortality link was effectively eliminated (0.92; 0.79 to 1.07).

CONCLUSIONS

In this cohort, socioeconomic position in middle age might lie on the pathway linking earlier IQ with later mortality risk but might also partly act as a surrogate for cognitive ability.

Active commuting to school: how far is too far?

BACKGROUND

Walking and cycling to school provide a convenient opportunity to incorporate physical activity into an adolescent's daily routine. School proximity to residential homes has been identified as an important determinant of active commuting among children. The purpose of this study is to identify if distance is a barrier to active commuting among adolescents, and if there is a criterion distance above which adolescents choose not to walk or cycle.

METHODS

Data was collected in 2003-05 from a cross-sectional cohort of 15-17 yr old adolescents in 61 post primary schools in Ireland. Participants self-reported distance, mode of transport to school and barriers to active commuting. Trained researchers took physical measurements of height and weight. The relation between mode of transport, gender and population density was examined. Distance was entered into a bivariate logistic regression model to predict mode choice, controlling for gender, population density socio-economic status and school clusters.

RESULTS

Of the 4013 adolescents who participated (48.1% female, mean age 16.02 +/- 0.661), one third walked or cycled to school. A higher proportion of males than females commuted actively (41.0 vs. 33.8%, chi2 (1) = 22.21, p < 0.001, r = -0.074). Adolescents living in more densely populated areas had greater odds of active commuting than those in the most sparsely populated areas (chi2 (df = 3) = 839.64, p < 0.001). In each density category, active commuters travelled shorter distances to school. After controlling for gender and population density, a 1-mile increase in distance decreased the odds of active commuting by 71% (chi2 (df = 1) = 2591.86, p < 0.001). The majority of walkers lived within 1.5 miles and cyclists within 2.5 miles. Over 90% of adolescents who perceived distance as a barrier to active commuting lived further than 2.5 miles from school.

CONCLUSION

Distance is an important perceived barrier to active commuting and a predictor of mode choice among adolescents. Distances within 2.5 miles are achievable for adolescent walkers and cyclists. Alternative strategies for increasing physical activity are required for individuals living outside of this criterion.

Assessment of physical activity and energy expenditure in epidemiological research of chronic diseases

Physical inactivity has emerged as an important risk factor for a number of diseases, but the typically crude exposure assessments in epidemiological studies, with entailing variation in measurement accuracy, may be a source of heterogeneity contributing to inconsistent results among studies. Consequently, the choice of method for the assessment of physical activity in epidemiological studies is important. Good methods increase our chances of avoiding misclassification and may enhance our understanding of the association between physical activity and health. Since physical activity is also a potential confounder of other lifestyle-health relationships, good methods may enhance our ability to control for confounding. But despite a steadily increasing selection of methods to choose from, no method is suitable for every situation and every population. Although the questionnaire is the most widely used method in epidemiological studies, and laboratory methods are mainly used for validation purposes, improved technology may change our ways of assessing physical activity in the future. This paper describes different methods to measure physical activity and energy expenditure from the epidemiological perspective, and attempts to address the concepts related to the measurement of physical activity.