Low intake of fruits,berries and vegetables is associated with excess mortality in men: the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study

Diets rich in fruits and vegetables have been of interest because of their potential health benefits against chronic diseases such as cardiovascular disease (CVD) and cancer. The aim of this work was to assess the association of the dietary intake of a food group that includes fruits, berries and vegetables with all-cause, CVD-related and non-CVD-related mortality. The subjects were Finnish men aged 42-60 y examined in 1984-1989 in the prospective Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study. Dietary intakes were assessed by 4-d food intake record during the baseline phase of the KIHD Study. The risk of all-cause and non-CVD-related deaths was studied in 2641 men and the risk of CVD-related death in 1950 men who had no history of CVD at baseline. During a mean follow-up time of 12.8 y, cardiovascular as well as noncardiovascular and all-cause mortality were lower among men with the highest consumption of fruits, berries and vegetables. After adjustment for the major CVD risk factors, the relative risk for men in the highest fifth of fruit, berry and vegetable intake for all-cause death, CVD-related and non-CVD-related death was 0.66 [95% confidence interval (CI) 0.50-0.88], 0.59 (0.33-1.06), and 0.68 (0.46-1.00), respectively, compared with men in the lowest fifth. These data show that a high fruit, berry and vegetable intake is associated with reduced risk of mortality in middle-aged Finnish men. Consequently, the findings of this work indicate that diets that are rich in plant-derived foods can promote longevity.     

Flavonoid intake and the risk of ischaemic stroke and CVD mortality in middle-aged Finnish men: the Kuopio Ischaemic Heart Disease Risk Factor Study

The role of flavonoids in CVD, especially in strokes, is unclear. Our aim was to study the role of flavonoids in CVD. We studied the association between the intakes of five subclasses (flavonols, flavones, flavanones, flavan-3-ols and anthocyanidins), a total of twenty-six flavonoids, on the risk of ischaemic stroke and CVD mortality. The study population consisted of 1950 eastern Finnish men aged 42-60 years free of prior CHD or stroke as part of the prospective population-based Kuopio Ischaemic Heart Disease Risk Factor Study. During an average follow-up time of 15.2 years, 102 ischaemic strokes and 153 CVD deaths occurred. In the Cox proportional hazards model adjusted for age and examination years, BMI,systolic blood pressure, hypertension medication, serum HDL- and LDL-cholesterol, serum TAG, maximal oxygen uptake, smoking, family history of CVD, diabetes, alcohol intake, energy-adjusted intake of folate, vitamin E, total fat and saturated fat intake (percentage of energy), men in the highest quartile of flavonol and flavan-3-ol intakes had a relative risk of 0.55 (95% CI 0.31, 0.99) and 0.59 (95% CI 0.30, 1.14) for ischaemic stroke, respectively, as compared with the lowest quartile. After multivariate adjustment, the relative risk for CVD death in the highest quartile of flavanone and flavone intakes were 0.54 (95% CI 0.32, 0.92) and 0.65 (95% CI 0.40, 1.05), respectively. The present results suggest that high intakes of flavonoids may be associated with decreased risk of ischaemic stroke and possibly with reduced CVD mortality.     

Serum lycopene concentrations and carotid atherosclerosis: the Kuopio Ischaemic Heart Disease Risk Factor Study

BACKGROUND: Interest in lycopene is growing rapidly following the recent publication of epidemiologic studies in which high circulating lycopene concentrations were associated with reductions in cardiovascular disease. Lycopene is one of the major carotenoids in the Western diet and is probably one of the protective factors in a vegetable-rich diet. OBJECTIVE: We studied the hypothesis that the intima-media thickness of the common carotid artery (CCA-IMT) would be greater in men with low serum lycopene concentrations. DESIGN: We investigated the relation between serum lycopene concentration and CCA-IMT in 1028 middle-aged men (aged 46-64 y) in eastern Finland who were participants in the Kuopio Ischaemic Heart Disease Risk Factor study and who were examined in 1991-1993. The subjects were classified into quarters according to serum lycopene concentration. RESULTS: In a covariance analysis with adjustment for covariates, the men in the lowest quarter of serum lycopene concentration had a significantly higher mean CCA-IMT and maximal CCA-IMT (P = 0.005 and P = 0.001 for the difference, respectively) than did the other men. The mean and maximal CCA-IMT increased linearly across the quarters of serum lycopene concentration. CONCLUSIONS: A low serum lycopene concentration is associated with a higher CCA-IMT in middle-aged men from eastern Finland. This finding suggests that the serum lycopene concentration may play a role in the early stages of atherosclerosis. Increased thickness of the intima-media has been shown to predict coronary events; thus, lycopene intakes and serum concentrations may have clinical and public health relevance.     

Serum β-Carotene in Relation to Risk of Prostate Cancer: The Kuopio Ischaemic Heart Disease Risk Factor Study

Results from epidemiologic studies on the association between circulating carotenoid concentrations and the risk of prostate cancer are still inconsistent. We studied whether serum concentrations of carotenoids were associated with the risk of developing prostate cancer. The study population consisted of 997 middle-aged Finnish men (56.1 ± 6.6 yr) in the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) cohort. Serum concentrations of carotenoids were measured by high-performance liquid chromatography. Subjects were classified into tertiles according to their serum concentrations of antioxidants. Relative risks (RRs) were estimated by using the Cox proportional hazard models. During the mean follow-up time of 15 yr, a total of 68 prostate cancer cases occurred. After adjusting for age, examination yr, family history of cancer, BMI, pack-yr of smoking, alcohol consumption, education, physical activity, serum total cholesterol, and serum α-linolenic acid, men in the highest tertile of serum concentrations of β-carotene had 2.3-fold higher risk of prostate cancer as compared to those in the lowest tertile (RR = 2.29, 95% CI: 1.12–4.66; P = 0.023). α-Tocopherol and retinol were not associated with prostate cancer. This prospective study suggests that high-serum β-carotene concentrations may increase the risk of prostate cancer in middle-aged men.     

Low serum folate concentrations are associated with an excess incidence of acute coronary events: the Kuopio Ischaemic Heart Disease Risk Factor Study

OBJECTIVE: To test the hypothesis that low serum folate concentrations are associated with an increased risk of acute coronary events in men free of prior coronary heart disease. SETTING: Research Institute of Public Health, University of Kuopio, Kuopio, Finland. DESIGN: Prospective study in a cohort of 734 men aged 46-64 y examined in 1991-1993 as part of the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) and followed for 5 y and 3 months. INTERVENTION: Acute coronary events during the follow-up period were obtained by national hospital discharge registry. Baseline serum folate concentrations were measured by radioimmunoassay. RESULTS: During the follow-up, six (2.5%) men with higher serum folate concentrations (highest third>11.3 nmol/1) and 28 (5.7%) men with lower serum folate (two lowest thirds) developed an acute coronary event (P=0.008). In a Cox model adjusting for age, examination years, and plasma lycopene concentration, in men with higher serum folate concentrations the relative risk for an acute coronary event was 0.31 (95% CI 0.11-0.90, P=0.031) when compared with men with lower serum folates. CONCLUSION: This prospective cohort study in middle-aged men from eastern Finland indicates that moderate-to-high levels of serum folate are associated with a greatly reduced incidence of acute coronary events.     

Serum folate and homocysteine and the incidence of acute coronary events: the Kuopio Ischaemic Heart Disease Risk Factor Study

BACKGROUND: Several, but not all, prospective studies have shown that low folate intakes, low circulating folate concentrations, or high plasma total homocysteine (tHcy) concentrations are associated with an increased risk of coronary artery disease (CAD). OBJECTIVE: We examined the relations of both serum folate and serum tHcy concentrations with acute coronary events in middle-aged men from eastern Finland who had no CAD at baseline. DESIGN: In a population-based prospective cohort study, 1027 men aged 46-64 y were examined in 1991-1993 as part of the Kuopio Ischaemic Heart Disease Risk Factor Study. During an average follow-up of 7.7 y (7900 person-years of follow-up), 114 acute coronary events were observed in 61 men who had no previous history of CAD (n = 810). RESULTS: In a Cox model, compared with men whose serum folate concentrations were in the lowest tertile, those whose concentrations were in the highest tertile had a risk factor-adjusted relative risk of acute coronary events of 0.35 (95% CI: 0.17, 0.73; P = 0.005). Serum tHcy concentrations were not significantly associated with the risk of acute coronary events (for the highest tertile compared with the lowest, adjusted relative risk = 1.03; 95% CI: 0.57, 1.87; P = 0.932). CONCLUSIONS: The results of this prospective cohort study do not support the hypothesis that a high circulating tHcy concentration is a risk factor for acute coronary events in a male population free of prior heart disease. However, they do suggest that moderate-to-high serum folate concentrations are associated with a greatly reduced incidence of acute coronary events.     

The intake of flavonoids and carotid atherosclerosis: the Kuopio Ischaemic Heart Disease Risk Factor Study

The role of flavonoids in CVD is still unclear. In this cross-sectional study we assessed the relation between the intakes of twenty-six flavonoids from five subclasses: flavonols, flavones, flavanones, flavan-3-ols and anthocyanidins, and the mean common carotid artery intima-media thickness (CCA-IMT). The study population consisted of 1380 middle-aged eastern Finnish men for whom the mean CCA-IMT examinations were carried out as a part of the prospective population-based Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD). The mean intake of flavonoids was 128.5 (sd 206.7) mg/d and the mean CCA-IMT was 0.78 (sd 0.17) mm. In the lowest quartile of total flavonoid intake the non-adjusted mean CCA-IMT was 0.79 (sd 0.19) mm, while the mean CCA-IMT was 0.76 (sd 0.15) in the highest quartile (P < 0.001). After adjustment for age, variables related to CCA-IMT measurement, history of atherosclerosis, smoking, BMI, diabetes, systolic blood pressure, serum HDL- and LDL-cholesterol, VO2 max, and intakes of alcohol, SFA, folate, vitamins C and E, the total flavonoid intake was inversely associated with the mean CCA-IMT (P = 0.018). Out of different flavonoid subclasses, flavan-3-ols were inversely associated with CCA-IMT (P = 0.025) after statistical adjustment. There was a trend for an inverse association between intake of flavonols and mean CCA-IMT (P = 0.055). We conclude that high intake of flavonoids is associated with decreased carotid atherosclerosis in middle-aged Finnish men.     

Intra-person variability of various physical activity assessments in the Kuopio Ischaemic Heart Disease Risk Factor Study.

We investigated the 12-month intra-person variability of various physical activity assessments used in the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) in 51 men aged 54 years. The methods were a 24-hour total activity recording, a 12-month leisure time activity history, a 7-day leisure time activity recall and a habitual occupational activity interview. More leisure time activity was reported in the retest. Intra-person variability was high for all physical activity indices. The proportion of the mean absolute test-retest difference out of the test-retest mean was 18% for the 24-hour total activity recording, 45% for the 12-month leisure time activity history, 86% for the 7-day leisure time activity recall, 70% for kilometres of conditioning activity per week (No. = 51) and 22% for the occupational activity interview (No. = 39). However, respective intraclass correlations for these indices were 0.43, 0.58, 0.35, 0.71 and 0.69. The physical activity assessments differ in observed intra-person variability in accordance with the type of activity, time frame and the method of recall. Owing to its representative time frame and relatively small intra-person variability the 12-month history may be recommended for a standard instrument for population studies concerning leisure time activity.     

Arginine intake,blood pressure,and the incidence of acute coronary events in men: the Kuopio Ischaemic Heart Disease Risk Factor Study

BACKGROUND: Evidence suggests that dietary supplementation of L-arginine, the precursor of nitric oxide, may protect arteries against atherosclerosis. OBJECTIVE: We tested the hypothesis that dietary arginine intake is associated with a decreased risk of acute coronary events in Finnish men aged 42-60 y. DESIGN: We investigated this association in a prospective cohort study of men who were free of prior coronary artery disease and who were examined in 1984-1989 in the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD). The dietary arginine intake of 1981 men was assessed by a 4-d food intake record during the baseline phase of the KIHD. RESULTS: Men in the highest quintile of dietary arginine intake (>or= 5691 mg/d) did not have a significantly lower risk of acute coronary events than did men in the 4 lower quintiles (relative risk after adjustment for potential coronary risk factors: 1.28; 95% CI: 0.85, 1.94). The covariates were age; examination years; body mass index; systolic blood pressure; serum total, HDL, and LDL cholesterol; serum triacylglycerols; urinary excretion of nicotine metabolites; maximal oxygen uptake in an exercise test; and alcohol intake. Splitting arginine intake into deciles or analyzing plant- and animal-derived arginine separately did not show any association between dietary arginine intake and the risk of acute coronary events. Arginine intake was also not consistently associated with blood pressure. CONCLUSION: Dietary arginine intake is not associated with the risk of acute coronary events in middle-aged men in eastern Finland.     

Low serum lycopene concentration is associated with an excess incidence of acute coronary events and stroke: the Kuopio Ischaemic Heart Disease Risk Factor Study.

A number of epidemiological studies have shown an association between beta-carotene and the risk of cardiovascular diseases, whereas only a few studies are available concerning the association of lycopene with the risk of coronary events, and no studies have been undertaken concerning lycopene and stroke. Thus, we tested the hypothesis that low serum levels of lycopene are associated with increased risk of acute coronary events and stroke in middle-aged men previously free of CHD and stroke. The subjects were 725 men aged 46-64 years examined in 1991-3 in the Kuopio Ischaemic Heart Disease Risk Factor Study. Forty-one men had either a fatal or a non-fatal acute coronary event or a stroke by December 1997. In a Cox' proportional hazard's model adjusting for examination years, age, systolic blood pressure and three nutritional factors (serum folate, beta-carotene and plasma vitamin C), men in the lowest quarter of serum lycopene levels (< or =0.07 micromol/l) had a 3.3-fold (95 % CI 1.7, 6.4, risk of acute coronary events or stroke compared with the others. Our study suggests that a low serum level of lycopene is associated with an increased risk of atherosclerotic vascular events in middle-aged men previously free of CHD and stroke.     

Serum magnesium and risk of new onset heart failure in men: the Kuopio Ischemic Heart Disease Study

Serum magnesium is an essential intracellular cation involved in processes that regulate cardiovascular function and has been linked to the risk of several cardiovascular disease outcomes. We aimed to investigate the association of serum magnesium concentrations with risk of incident heart failure (HF). We studied 2181 middle-aged men without prevalent HF (aged 42–61 years) enrolled in the finnish Kuopio Ischemic Heart Disease prospective cohort study with serum magnesium measurements made at baseline. Hazard ratios (95 % confidence intervals [CI]) for HF were assessed. During a median follow-up of 24.8 years, 278 HF events occurred. Baseline serum magnesium was weakly and inversely associated with several clinical markers and was continuously associated with risk of HF. The age-adjusted HR (95 % CIs) for HF per 1 standard deviation (SD) higher serum magnesium levels was 0.86 (0.76–0.97). The HR (95 % CIs) was 0.87 (0.76–0.98) after controlling for measures of adiposity, socio-economic variables, medical history, blood pressure, renal function, alcohol consumption, and lipids. These findings remained consistent in analyses accounting for incident coronary heart disease. The results were comparable across several clinically relevant subgroups and analyses with atrial fibrillation as a competing risk yielded similar results. Serum magnesium was continuously, inversely and independently associated with future risk of HF. Further research is needed to assess any potential relevance of serum magnesium in HF prevention.     

Serum levels of polyunsaturated fatty acids are low in Chinese men with metabolic syndrome,whereas serum levels of saturated fatty acids,zinc, and magnesium are high

The purpose of this study was to examine the hypothesis that serum levels of phospholipid (PL) fatty acids (FA) and minerals are associated with the components of metabolic syndrome (MetS) in the Chinese population and the profiles of changes may differ from patients with MetS from Western countries. The levels of serum PL, FA, and minerals were examined in 201 subjects (52 with MetS and 149 healthy controls without any MetS components) in China. The saturated FA proportion in serum was significantly higher, whereas the proportion of total polyunsaturated FA (PUFA), n-3 and n-6 PUFA (22:6n-3: −16%, P = .006; 20:4n-6: −36%, P < .001), and estimated δ-5 desaturase were significantly lower in the MetS group compared with those that are not MetS. Subjects with MetS had higher levels of serum Zn (P = .037) and Mg (P < .001) than subjects without MetS. The proportion of n-3 PUFA was significantly negatively correlated with body mass index and waist circumference. In conclusion, serum PL FA composition and serum minerals in Chinese men with MetS differed significantly from that of healthy individuals, reflecting a decrease in n-3 and n-6 PUFA, especially 22:6n-3 and 20:4n-6, and an increase in saturated FA, magnesium, and zinc. These changes may reflect improper dietary intake in subjects with MetS, and dietary modification could be useful to prevent MetS and as an adjunctive therapy.     

Workplace conditions, socioeconomic status, and the risk of mortality and acute myocardial infarction: the Kuopio Ischemic Heart Disease Risk Factor Study.

OBJECTIVES: This study investigated whether the association between workplace conditions and the risk of all-cause and cardiovascular mortality and acute myocardial infarction differed by socioeconomic status. METHODS: Prospective data were used to examine these associations in 2297 Finnish men, with adjustment for prevalent diseases and biological, behavioral, and psychosocial covariates, and stratified by employment status and workplace social support. RESULTS: Elevated age-adjusted relative hazards for all-cause mortality were found for men who reported high demands, low resources, and low income; high demands, high resources, and low income; and low demands, high resources, and low income. Similar patterns were found for cardiovascular mortality. In contrast, elevated age-adjusted relative hazards for acute myocardial infarction were observed only in men who reported high demands, low resources, and low income. These results did not differ by level of workplace social support or employment status. CONCLUSIONS: The negative effects of workplace conditions on mortality and of myocardial infarction risk depended on income level and were largely mediated by known risk factors.     

Serum fatty acid composition and indices of stearoyl-CoA desaturase activity are associated with systemic inflammation: longitudinal analyses in middle-aged men

Altered fatty acid (FA) composition is related to insulin resistance and CVD. One possible mediator may be inflammation, but longitudinal data relating FA composition to inflammation taking insulin resistance into account are limited. We investigated the long-term association between FA composition and C-reactive protein (CRP) concentrations in a large population-based cohort study in 767 men followed for 20 years. The association between FA composition in serum cholesteryl esters at age 50 and CRP concentrations at age 70 was investigated using linear regression. In addition, desaturase activities (stearoyl-CoA desaturase-1 (SCD-1), Delta5- and Delta6-desaturase) were estimated using FA product-to-precursor ratios. Insulin resistance was measured directly at follow-up by euglycaemic clamp. After adjusting for confounders (smoking, physical activity, alcohol intake, obesity and erythrocyte sedimentation rate) CRP concentrations were inversely associated with the proportion of 18:2n-6 (P = 0.002) and positively associated with 16:1n-7 (P = 0.008), 18:1n-9 (P = 0.0003), 20:5n-3 (P = 0.04) and estimated SCD-1 (P = 0.005) and Delta6-desaturase (P = 0.02) activities. After adding insulin resistance to the model, 18:1n-9, 18:2n-6 and SCD-1 remained significant predictors of CRP. A FA composition indicating low intake of 18:2n-6, high intake of SFA and high SCD-1 activity is, in a Swedish population of middle-aged men, associated with CRP concentrations 20 years later, even independently of obesity and insulin resistance.     

Serum fatty acids,lipoprotein (a) and apolipoprotein profiles of middle-aged men and women in South Vietnam

In Vietnam, increasing fat consumption is a trend recognized recently in urban areas. To obtain a reasonable nutrition status and prevent cardiovascular disease (CVD), it is necessary to obtain information on habitual fat intake and biochemical parameters as risk factors for CVD in Vietnamese populations. Therefore, from the analysis of serum fatty acid composition, fat consumption patterns in Vietnamese populations in South Vietnam, with different incomes, are discussed in this study. In addition, some risk factors for premature CVD, serum lipoprotein (a) and apolipoprotein concentrations are also assessed in these Vietnamese populations. The study was carried out in men and women aged 40-59 in three different districts: urban (n = 100), suburban (n = 98) and rural (n = 98). The results of serum fatty acid composition analysis reflected differences in quality fat intake among the three populations. The urban population was estimated to consume more vegetable oil but less fish than their rural counterparts. Although serum lipoprotein (a) and apolipoprotein B levels were below the ranges associated with atherogenesis, ongoing attention to dietary fat intake for the prevention of CVD in Vietnamese populations is required.     

The lipid-lowering effects of phytosterols and (n-3) polyunsaturated fatty acids are synergistic and complementary in hyperlipidemic men and women

Fish oils rich in (n-3) long-chain PUFA (LCPUFA) can reduce circulating triglycerides and raise HDL-cholesterol. Phytosterols have been shown to reduce total cholesterol and LDL-cholesterol in normocholesterolemic and hyperlipidemic populations. We investigated the combined effects of phytosterols and (n-3) LCPUFA on plasma lipid profile in hyperlipidemic individuals. This study was a 3-wk randomized, double-blind, placebo-controlled, 2 x 2 factorial trial in 4 parallel groups of 60 hyperlipidemic individuals. Subjects were randomized to receive either sunola oil or 1.4 g/d (n-3) LCPUFA capsules with or without 2 g phytosterols per day while maintaining their habitual diet. The combination of phytosterols and (n-3) LCPUFA reduced plasma total cholesterol by 13.3% (P = 0.001), which differed from (n-3) LCPUFA alone (P < 0.001). LDL-cholesterol concentrations followed the same pattern as that of plasma cholesterol with a 12.5% decrease (P = 0.002) in the combination group. The HDL-cholesterol concentration was increased by (n-3) LCPUFA (7.1%; P = 0.01) alone and in combination with phytosterols (8.6%; P = 0.04), whereas phytosterol treatment alone had no effect. Plasma triglyceride concentration was lowered by (n-3) LCPUFA (22.3%; P = 0.004) alone and in combination with phytosterols (25.9%; P = 0.005), whereas phytosterol treatment alone had no effect. In conclusion, the combined supplementation with phytosterols and (n-3) LCPUFA has both synergistic and complementary lipid-lowering effects in hyperlipidemic men and women.     

Multivitamin supplements are inversely associated with risk of myocardial infarction in men and women--Stockholm Heart Epidemiology Program (SHEEP)

Epidemiologic data relating multivitamin supplement use to the risk of cardiovascular disease are sparse and inconsistent. We examined the association between self-selected use of low dose multivitamin supplements and the risk of myocardial infarction (MI). Our results are based on data from a large population-based, case-control study of subjects aged 45-70 y residing in Sweden, a country in which consumption of fruits and vegetables is relatively low and foods are not fortified with folic acid. The study included 1296 cases (910 men, 386 women) with a first nonfatal MI and 1685 controls (1143 men, 542 women) frequency-matched to the cases by sex, age and hospital catchment area. Odds ratios (OR) and 95% CI were calculated from unconditional logistic regression models. Among controls, 57% of the women and 35% of the men used dietary supplements; corresponding figures for the cases were 42 and 27%, respectively. Of those taking supplements, 80% used multivitamin preparations. After adjustment for major cardiovascular risk factors, the OR of MI comparing regular users of supplements with nonusers were 0.79 (95% CI 0.63-0.98) for men and 0.66 (95% CI 0.48-0.91) for women. This inverse association was not modified by such healthy lifestyle habits as consumption of fruits and vegetables, intake of dietary fiber, smoking habits and level of physical activity, although never smoking appeared to outweigh the association in women. Findings from this study indicate that use of low dose multivitamin supplements may aid in the primary prevention of MI.     

Prospective Analysis of Traffic Exposure as a Risk Factor for Incident Coronary Heart Disease: The Atherosclerosis Risk in Communities (ARIC) Study

Background

For people living close to busy roads, traffic is a major source of air pollution. Few prospective data have been published on the effects of long-term exposure to traffic on the incidence of coronary heart disease (CHD).

Objectives

In this article, we examined the association between long-term traffic exposure and incidence of fatal and nonfatal CHD in a population-based prospective cohort study.

Methods

We studied 13,309 middle-age men and women in the Atherosclerosis Risk in Communities study, without previous CHD at enrollment, from 1987 to 1989 in four U.S. communities. Geographic information system–mapped traffic density and distance to major roads served as measures of traffic exposure. We examined the association between traffic exposure and incident CHD using proportional hazards regression models, with adjustment for background air pollution and a wide range of individual cardiovascular risk factors.

Results

Over an average of 13 years of follow-up, 976 subjects developed CHD. Relative to those in the lowest quartile of traffic density, the adjusted hazard ratio (HR) in the highest quartile was 1.32 [95% confidence interval (CI), 1.06–1.65; p-value for trend across quartiles = 0.042]. When we treated traffic density as a continuous variable, the adjusted HR per one unit increase of log-transformed density was 1.03 (95% CI, 1.01–1.05; p = 0.006). For residents living within 300 m of major roads compared with those living farther away, the adjusted HR was 1.12 (95% CI, 0.95–1.32; p = 0.189). We found little evidence of effect modification for sex, smoking status, obesity, low-density lipoprotein cholesterol level, hypertension, age, or education.

Conclusion

Higher long-term exposure to traffic is associated with incidence of CHD, independent of other risk factors. These prospective data support an effect of traffic-related air pollution on the development of CHD in middle-age persons.     

Erythrocyte membrane n-3 polyunsaturated fatty acids are inversely associated with the presence and progression of nonalcoholic fatty liver disease in Chinese adults: a prospective study

Previous studies have shown that high-dose supplementation with n-3 polyunsaturated fatty acids (PUFAs) may benefit patients with nonalcoholic fatty liver disease (NAFLD), but the association of n-3 PUFAs with NAFLD among individuals with normal diets is only speculative. We investigated the cross-sectional and prospective associations between n-3 PUFAs and NAFLD in Chinese adults. This community-based prospective study included 3049 men and women (40–75 years) in Guangzhou, China, whose participants completed an NAFLD ultrasound evaluation and erythrocyte PUFA tests. A total of 2660 participants underwent the second NAFLD evaluation approximately 3 years later. α-Linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in erythrocytes were measured by gas chromatography. After adjusting for potential confounders, we observed inverse associations between DHA, DHA + EPA, total n-3 PUFAs and the presence of NAFLD in the cross-sectional analysis. The adjusted odds ratios (95% confidence interval) of NAFLD for the highest (vs. lowest) tertile were 0.74 (0.61, 0.90) for DHA, 0.82 (0.67, 1.00) for EPA, 0.73 (0.60, 0.88) for DHA + EPA and 0.74 (0.61, 0.91) for total n-3 PUFAs  (all P values≤0.05). Over the average 3.12 years of follow-up, higher levels of DHA was associated with an improvement of NAFLD. The hazard ratio of improved NAFLD for the highest tertile was 1.18 (95% CI 1.09, 1.33) for DHA. Pathway analyses showed that favorable associations may be mediated by improvements in inflammatory markers (e.g., interleukin 1 beta and tumor necrosis factor alpha-like). Erythrocyte membrane n-3 PUFAs are inversely associated with the presence and progression of NAFLD in Chinese adults. ClinicalTrials.gov NCT03179657.