A combined analysis of the short-term effects of photochemical air pollutants on mortality within the EMECAM project.

In recent years, some epidemiologic studies have attributed adverse effects of air pollutants on health not only to particles and sulfur dioxide but also to photochemical air pollutants (nitrogen dioxide and ozone). The effects are usually small, leading to some inconsistencies in the results of the studies. Furthermore, the different methodologic approaches of the studies used has made it difficult to derive generic conclusions. We provide here a quantitative summary of the short-term effects of photochemical air pollutants on mortality in seven Spanish cities involved in the EMECAM project, using generalized additive models from analyses of single and multiple pollutants. Nitrogen dioxide and ozone data were provided by seven EMECAM cities (Barcelona, Gijón, Huelva, Madrid, Oviedo, Seville, and Valencia). Mortality indicators included daily total mortality from all causes excluding external causes, daily cardiovascular mortality, and daily respiratory mortality. Individual estimates, obtained from city-specific generalized additive Poisson autoregressive models, were combined by means of fixed effects models and, if significant heterogeneity among local estimates was found, also by random effects models. Significant positive associations were found between daily mortality (all causes and cardiovascular) and NO(2), once the rest of air pollutants were taken into account. A 10 microg/m(3) increase in the 24-hr average 1-day NO(2)level was associated with an increase in the daily number of deaths of 0.43% [95% confidence interval (CI), -0.003-0.86%] for all causes excluding external. In the case of significant relationships, relative risks for cause-specific mortality were nearly twice as much as that for total mortality for all the photochemical pollutants. Ozone was independently related only to cardiovascular daily mortality. No independent statistically significant relationship between photochemical air pollutants and respiratory mortality was found. The results in this study suggest that, given the present levels of photochemical pollutants, people living in Spanish cities are exposed to health risks derived from air pollution.

Who is at low risk for cardiovascular disease?: an assessment of different definitions

Purpose: to assess the prevalence and trends of low cardiovascular risk factor (RF) profile in the Swiss population according to different definitions. Methods: Population-based cross-sectional study of 6170 subjects (3241 women) aged 35-75 years living in Lausanne, Switzerland. Trends were assessed using data from the Swiss MONICA population surveys conducted in 1984-6 (N = 3300), 1988-9 (N = 3331) and 1992-3 (N = 3133) and restricted to the same age group. Seven different definitions of low RF profile were used. Results: prevalence of low RF profile varied between 6.5% (95% confidence interval: 5.9-7.1) and 9.7% (9.0-10.5) depending on the definition used (see fig. 1). The prevalence was inversely related to the number of criteria used and higher than in other countries. Irrespective of the definition used, the prevalence of low RF profile was higher in women and in physically active participants, and decreased with increasing age or in the presence of a family history of cardiovascular disease. The prevalence of low RF profile increased from 3.8% (3.1- 4.5) in 1984-6 to 6.7% (6.1-7.3) in 2003-6; using another definition, the results were 5.9% (5.1-6.8) and 9.7% (9.0-10.5), respectively (see fig. 2). Conclusion: the prevalence of low RF profile varies according to the criteria used; this prevalence is relatively high and increasing in the Swiss population, which might partly explain the low and decreasing trend in cardiovascular mortality rates.

Inverse association between circulating vitamin D and mortality-dependent on sex and cause of death?

BACKGROUND AND AIMS: In various populations, vitamin D deficiency is associated with chronic diseases and mortality. We examined the association between concentration of circulating 25-hydroxyvitamin D [25(OH)D], a marker of vitamin D status, and all-cause as well as cause-specific mortality. METHODS AND RESULTS: The study included 3404 participants of the general adult Swiss population, who were recruited between November 1988 and June 1989 and followed-up until the end of 2008. Circulating 25(OH)D was measured by protein-bound assay. Cox proportional hazards regression was used to examine the association between 25(OH)D concentration and all-cause and cause-specific mortality adjusting for sex, age, season, diet, nationality, blood pressure, and smoking status. Per 10 ng/mL increase in 25(OH)D concentration, all-cause mortality decreased by 20% (HR = 0.83; 95% CI 0.74-0.92). 25(OH)D concentration was inversely associated with cardiovascular mortality in women (HR = 0.68, 95% CI 0.46-1.00 per 10 ng/mL increase), but not in men (HR = 0.97; 95% CI 0.77-1.23). In contrast, 25(OH)D concentration was inversely associated with cancer mortality in men (HR = 0.72, 95% CI 0.57-0.91 per 10 ng/mL increase), but not in women (HR = 1.14, 95% CI 0.93-1.39). Multivariate adjustment only slightly modified the 25(OH)D-mortality association. CONCLUSION: 25(OH)D was similarly inversely related to all-cause mortality in men and women. However, we observed opposite effects in women and men with respect to cardiovascular and cancer mortality.

Association of socioeconomic position with health behaviors and mortality

CONTEXT: Previous studies may have underestimated the contribution of health behaviors to social inequalities in mortality because health behaviors were assessed only at the baseline of the study. OBJECTIVE: To examine the role of health behaviors in the association between socioeconomic position and mortality and compare whether their contribution differs when assessed at only 1 point in time with that assessed longitudinally through the follow-up period. DESIGN, SETTING, AND PARTICIPANTS: Established in 1985, the British Whitehall II longitudinal cohort study includes 10 308 civil servants, aged 35 to 55 years, living in London, England. Analyses are based on 9590 men and women followed up for mortality until April 30, 2009. Socioeconomic position was derived from civil service employment grade (high, intermediate, and low) at baseline. Smoking, alcohol consumption, diet, and physical activity were assessed 4 times during the follow-up period. MAIN OUTCOME MEASURES: All-cause and cause-specific mortality. RESULTS: A total of 654 participants died during the follow-up period. In the analyses adjusted for sex and year of birth, those with the lowest socioeconomic position had 1.60 times higher risk of death from all causes than those with the highest socioeconomic position (a rate difference of 1.94/1000 person-years). This association was attenuated by 42% (95% confidence interval [CI], 21%-94%) when health behaviors assessed at baseline were entered into the model and by 72% (95% CI, 42%-154%) when they were entered as time-dependent covariates. The corresponding attenuations were 29% (95% CI, 11%-54%) and 45% (95% CI, 24%-79%) for cardiovascular mortality and 61% (95% CI, 16%-425%) and 94% (95% CI, 35%-595%) for noncancer and noncardiovascular mortality. The difference between the baseline only and repeated assessments of health behaviors was mostly due to an increased explanatory power of diet (from 7% to 17% for all-cause mortality, respectively), physical activity (from 5% to 21% for all-cause mortality), and alcohol consumption (from 3% to 12% for all-cause mortality). The role of smoking, the strongest mediator in these analyses, did not change when using baseline or repeat assessments (from 32% to 35% for all-cause mortality). CONCLUSION: In a civil service population in London, England, there was an association between socioeconomic position and mortality that was substantially accounted for by adjustment for health behaviors, particularly when the behaviors were assessed repeatedly.

Traitements des facteurs de risque cardiovasculaire et dépistage de la maladie coronarienne dans le diabète de type 2 [Treatments for cardiovascular risk factors and screening for coronary artery disease in type 2 diabetes mellitus]

The recent ACCORD and DIAD studies revealed results which could modify treatments and the screening of diabetes vascular complications. Indeed, ACCORD shows no benefit on the prevention of diabetes vascular complications by aggressive treatment of hypertension or the combined treatment of the dyslipidemia. The intensive treatment of the blood glucose, if associated with severe hypoglycemias, increases mortality. DIAD revealed 20% of silent myocardial ischaemia in diabetic patients but no beneficial effect on the cardiovascular mortality. A careful reading of these studies in the light of long term studies such as UKPDS and STENO reveals that these negative results are generated by a too short follow-up and too aggressive objectives. The long term studies reveal that more realistic objectives remain beneficial.

Who is at low risk for cardiovascular disease? An assessment of different definitions

Purpose: To assess the prevalence and trends of low cardiovascular risk factor (RF) profile in the Swiss population according to different definitions. Methods: Population-based cross-sectional study of 6170 subjects (3241 women) aged 35-75 years living in Lausanne, Switzerland. Trends were assessed using data from the Swiss MONICA population surveys conducted in 1984-6 (N=3300), 1988-9 (N=3331) and 1992-3 (N=3133) and restricted to the same age group. Seven different definitions of low RF profile were used. Results: Prevalence of low RF profile varied between 6.5% (95% confidence interval: 5.9-7.1) and 9.7% (9.0-10.5) depending on the definition used. The prevalence was inversely related to the number of criteria used and higher than in other countries. Irrespective of the definition used, the prevalence of low RF profile was higher in women and in physically active participants, and decreased with increasing age or in the presence of a family history of cardiovascular disease (table). The prevalence of low RF profile increased from 3.8% (3.1-4.5) in 1984-6 to 6.7% (6.1-7.3) in 2003-6; using another definition, the results were 5.9% (5.1-6.8) and 9.7% (9.0-10.5), respectively. Conclusion: The prevalence of low RF profile varies according to the criteria used; this prevalence is relatively high and increasing in the Swiss population, which might partly explain the low and decreasing trend in cardiovascular mortality rates.

Do different measures of early life socioeconomic circumstances predict adult mortality? Evidence from the British Whitehall II and French GAZEL studies

BACKGROUND: Father's occupational position, education and height have all been used to examine the effects of adverse early life socioeconomic circumstances on health, but it remains unknown whether they predict mortality equally well. METHODS: We used pooled data on 18,393 men and 7060 women from the Whitehall II and GAZEL cohorts to examine associations between early life socioeconomic circumstances and all-cause and cause-specific mortality. RESULTS: During the 20-y follow-up period, 1487 participants died. Education had a monotonic association with all mortality outcomes; the age, sex and cohort-adjusted HR for the lowest versus the highest educational group was 1.45 (95% CI 1.24 to 1.69) for all-cause mortality. There was evidence of a U-shaped association between height and all-cause, cancer and cardiovascular mortality robust to adjustment for the other indicators (HR 1.41, 95% CI 1.03 to 1.93 for those shorter than average and HR 1.36, 95% CI 0.98 to 1.88 for those taller than average for cardiovascular mortality). Greater all-cause and cancer mortality was observed in participants whose father's occupational position was manual rather than non-manual (HR 1.11, 95% CI 1.00 to 1.23 for all-cause mortality), but the risks were attenuated after adjusting for education and height. CONCLUSIONS: The association between early life socioeconomic circumstances and mortality depends on the socioeconomic indicator used and the cause of death examined. Height is not a straightforward measure of early life socioeconomic circumstances as taller people do not have a health advantage for all mortality outcomes.

Association of ischaemic stroke subtype with long-term cardiovascular events.

BACKGROUND AND PURPOSE: There is no strong evidence that all ischaemic stroke types are associated with high cardiovascular risk. Our aim was to investigate whether all ischaemic stroke types are associated with high cardiovascular risk. METHODS: All consecutive patients with ischaemic stroke registered in the Athens Stroke Registry between 1 January 1993 and 31 December 2010 were categorized according to the TOAST classification and were followed up for up to 10 years. Outcomes assessed were cardiovascular and all-cause mortality, myocardial infarction, stroke recurrence, and a composite cardiovascular outcome consisting of myocardial infarction, angina pectoris, acute heart failure, sudden cardiac death, stroke recurrence and aortic aneurysm rupture. The Kaplan-Meier product limit method was used to estimate the probability of each end-point in each patient group. Cox proportional hazards models were used to determine the independent covariates of each end-point. RESULTS: Two thousand seven hundred and thirty patients were followed up for 48.1 ± 41.9 months. The cumulative probabilities of 10-year cardiovascular mortality in patients with cardioembolic stroke [46.6%, 95% confidence interval (CI) 40.6-52.8], lacunar stroke (22.1%, 95% CI 16.2-28.0) or undetermined stroke (35.2%, 95% CI 27.8-42.6) were either similar to or higher than those of patients with large-artery atherosclerotic stroke (LAA) (28.7%, 95% CI 22.4-35.0). Compared with LAA, all other TOAST types had a higher probability of 10-year stroke recurrence. In Cox proportional hazards analysis, compared with patients with LAA, patients with any other stroke type were associated with similar or higher risk for the outcomes of overall mortality, cardiovascular mortality, stroke recurrence and composite cardiovascular outcome. CONCLUSIONS: Large-artery atherosclerotic stroke and cardioembolic stroke are associated with the highest risk for future cardiovascular events, with the latter carrying at least as high a risk as LAA stroke.

Opposite impacts of dietary versus supplemental calcium on cardiovascular health.

Commentary on: Li K, Kaaks R, Linseisen J, et al . Associations of dietary calcium intake and calcium supplementation with myocardial infarction and stroke risk and overall cardiovascular mortality in the Heidelberg cohort of the European prospective investigation into cancer and nutrition study (EPIC-Heidelberg). Heart 2012; 98 :920 - 5

Aldosterone and cardiovascular risk.

Through its classic effects on sodium and potassium homeostasis, aldosterone, when produced in excess, is associated with the development of hypertension and hence with higher cardiovascular and renal risk. In recent years, experimental and epidemiologic data have suggested that aldosterone also may be linked to high cardiovascular risk independently of its effects on blood pressure. Thus, aldosterone has been associated with obesity and metabolic syndrome in selected populations, and these associations may further contribute to the higher cardiovascular risk of subjects with elevated aldosterone levels. Moreover, aldosterone has been reported to promote inflammation, oxidative stress, and fibrosis in a number of tissues. Clinical evidence indicates that patients with primary hyperaldosteronism have a higher risk of developing cardiovascular and renal complications than patients with essential hypertension who have the same level of blood pressure. Aldosterone receptor blockade has been shown to lower cardiovascular mortality after myocardial infarction and in patients with congestive heart failure. Some studies have also demonstrated that aldosterone blockade could have a favorable impact on the progression of renal disease. However, prospective interventional trials are needed to further evaluate the impact of blockade of aldosterone on cardiovascular risk.

The ADVANCE trial: clarifying the role of perindopril/indapamide fixed-dose combination in the reduction of cardiovascular and renal events in patients with diabetes mellitus.

Patients with type 2 diabetes mellitus exhibit a marked increase in cardiovascular and renal risk. A number of interventional trials have shown that these patients benefit greatly from aggressive BP lowering, especially when the drug regimen comprises an inhibitor of the renin-angiotensin system. The results of the placebo-controlled ADVANCE (Action in Diabetes and Vascular disease: PreterAx and DiamicroN MR Controlled Evaluation) trial, conducted in patients with type 2 diabetes, are exemplary in this respect. The systematic use of a fixed-dose combination containing the ACE inhibitor perindopril and the diuretic indapamide afforded substantial protection against cardiovascular mortality and myocardial infarction, while providing important renoprotection, reducing the development of micro- and macroalbuminuria, and allowing regression of nephropathy. The beneficial effects were obtained regardless of baseline BP and whether or not the patients were receiving antihypertensive therapy.

Meta-analysis: subclinical thyroid dysfunction and the risk for coronary heart disease and mortality

BACKGROUND: Data on the association between subclinical thyroid dysfunction and coronary heart disease (CHD) and mortality are conflicting. PURPOSE: To summarize prospective evidence about the relationship between subclinical thyroid dysfunction and CHD and mortality. DATA SOURCES: MEDLINE (1950 to January 2008) without language restrictions and reference lists of retrieved articles were searched. STUDY SELECTION: Two reviewers screened and selected cohort studies that measured thyroid function and then followed persons prospectively to assess CHD or mortality. DATA EXTRACTION: By using a standardized protocol and forms, 2 reviewers independently abstracted and assessed studies. DATA SYNTHESIS: Ten of 12 identified studies involved population-based cohorts that included 14 449 participants. All 10 population-based cohort studies examined risks associated with subclinical hypothyroidism (2134 CHD events and 2822 deaths), whereas only 5 examined risks associated with subclinical hyperthyroidism (1392 CHD events and 1993 deaths). In a random-effects model, the relative risk (RR) for subclinical hypothyroidism for CHD was 1.20 (95% CI, 0.97 to 1.49; P for heterogeneity = 0.14; I(2 )= 33.4%). Risk estimates were lower when higher-quality studies were pooled (RR, 1.02 to 1.08) and were higher among participants younger than 65 years (RR, 1.51 [CI, 1.09 to 2.09] for studies with mean participant age <65 years and 1.05 [CI, 0.90 to 1.22] for studies with mean participant age > or =65 years). The RR was 1.18 (CI, 0.98 to 1.42) for cardiovascular mortality and 1.12 (CI, 0.99 to 1.26) for total mortality. For subclinical hyperthyroidism, the RR was 1.21 (CI, 0.88 to 1.68) for CHD, 1.19 (CI, 0.81 to 1.76) for cardiovascular mortality, and 1.12 (CI, 0.89 to 1.42) for total mortality (P for heterogeneity >0.50; I(2 )= 0% for all studies). LIMITATIONS: Individual studies adjusted for different potential confounders, and 1 study provided only unadjusted data. Publication bias or selective reporting of outcomes could not be excluded. CONCLUSION: Subclinical hypothyroidism and hyperthyroidism may be associated with a modest increased risk for CHD and mortality, with lower risk estimates when pooling higher-quality studies and larger CIs for subclinical hyperthyroidism

Metabolic syndrome and the risk of cardiovascular disease in older adults.

OBJECTIVES: The purpose of this study was to assess whether metabolic syndrome (MetSyn) predicts a higher risk for cardiovascular events in older adults. BACKGROUND: The importance of MetSyn as a risk factor has not previously focused on older adults and deserves further study. METHODS: We studied the impact of MetSyn (38% prevalence) on outcomes in 3,035 participants in the Health, Aging, and Body Composition (Health ABC) study (51% women, 42% black, ages 70 to 79 years). RESULTS: During a 6-year follow-up, there were 434 deaths overall, 472 coronary events (CE), 213 myocardial infarctions (MI), and 231 heart failure (HF) hospital stays; 59% of the subjects had at least one hospital stay. Coronary events, MI, HF, and overall hospital stays occurred significantly more in subjects with MetSyn (19.9% vs. 12.9% for CE, 9.1% vs. 5.7% for MI, 10.0% vs. 6.1% for HF, and 63.1% vs. 56.1% for overall hospital stay; all p < 0.001). No significant differences in overall mortality was seen; however, there was a trend toward higher cardiovascular mortality (5.1% vs. 3.8%, p = 0.067) and coronary mortality (4.5% vs. 3.2%, p = 0.051) in patients with MetSyn. After adjusting for baseline characteristics, patients with MetSyn were at a significantly higher risk for CE (hazard ratio [HR] 1.56, 95% confidence interval [CI] 1.28 to 1.91), MI (HR 1.51, 95% CI 1.12 to 2.05), and HF hospital stay (HR 1.49, 95% CI 1.10 to 2.00). Women and whites with MetSyn had a higher coronary mortality rate. The CE rate was higher among subjects with diabetes and with MetSyn; those with both had the highest risk. CONCLUSIONS: Overall, subjects over 70 years are at high risk for cardiovascular events; MetSyn in this group is associated with a significantly greater risk.

Effect of air pollution on diabetes and cardiovascular diseases in São Paulo, Brazil

Type 2 diabetes increases the risk of cardiovascular mortality and these patients, even without previous myocardial infarction, run the risk of fatal coronary heart disease similar to non-diabetic patients surviving myocardial infarction. There is evidence showing that particulate matter air pollution is associated with increases in cardiopulmonary morbidity and mortality. The present study was carried out to evaluate the effect of diabetes mellitus on the association of air pollution with cardiovascular emergency room visits in a tertiary referral hospital in the city of São Paulo. Using a time-series approach, and adopting generalized linear Poisson regression models, we assessed the effect of daily variations in PM10, CO, NO2, SO2, and O3 on the daily number of emergency room visits for cardiovascular diseases in diabetic and non-diabetic patients from 2001 to 2003. A semi-parametric smoother (natural spline) was adopted to control long-term trends, linear term seasonal usage and weather variables. In this period, 45,000 cardiovascular emergency room visits were registered. The observed increase in interquartile range within the 2-day moving average of 8.0 µg/m³ SO2 was associated with 7.0% (95%CI: 4.0-11.0) and 20.0% (95%CI: 5.0-44.0) increases in cardiovascular disease emergency room visits by non-diabetic and diabetic groups, respectively. These data indicate that air pollution causes an increase of cardiovascular emergency room visits, and that diabetic patients are extremely susceptible to the adverse effects of air pollution on their health conditions.

Combined Analysis of the Short-Term Effects of Photochemical Air Pollutants on Mortality within the EMECAM Project

In recent years, some epidemiologic studies have attributed adverse effects of air pollutants on health not only to particles and sulfur dioxide but also to photochemical air pollutants (nitrogen dioxide and ozone). The effects are usually small, leading to some inconsistencies in the results of the studies. Furthermore, the different methodologic approaches of the studies used has made it difficult to derive generic conclusions. We provide here a quantitative summary of the short-term effects of photochemical air pollutants on mortality in seven Spanish cities involved in the EMECAM project, using generalized additive models from analyses of single and multiple pollutants. Nitrogen dioxide and ozone data were provided by seven EMECAM cities (Barcelona, Gijón, Huelva, Madrid, Oviedo, Seville, and Valencia). Mortality indicators included daily total mortality from all causes excluding external causes, daily cardiovascular mortality, and daily respiratory mortality. Individual estimates, obtained from city-specific generalized additive Poisson autoregressive models, were combined by means of fixed effects models and, if significant heterogeneity among local estimates was found, also by random effects models. Significant positive associations were found between daily mortality (all causes and cardiovascular) and NO2, once the rest of air pollutants were taken into account. A 10 μg/m3 increase in the 24-hr average 1-day NO2 level was associated with an increase in the daily number of deaths of 0.43% [95% confidence interval(CI), –0.003–0.86%] for all causes excluding external. In the case of significant relationships, relative risks for cause-specific mortality were nearly twice as much as that for total mortality for all the photochemical pollutants. Ozone was independently related only to cardiovascular daily mortality. No independent statistically significant relationship between photochemical air pollutants and respiratory mortality was found. The results in this study suggest that, given the present levels of photochemical pollutants, people living in Spanish cities are exposed to health risks derived from air pollution