Underestimation of risk associations due to regression dilution in long-term follow-up of prospective studies

Chronic renal dysfunction, proteinuria, and risk of Parkinson's disease in the elderly

BACKGROUND

The roles of chronic kidney disease and proteinuria in the development of Parkinson's disease have not been widely studied. The objective of this study was to examine the associations of chronic renal dysfunction and proteinuria with the risk of PD in older adults using cohort data of the whole South Korean population.

METHODS

We included 3,580,435 individuals aged ≥65 years who had undergone health checkups provided by the National Health Insurance Service of South Korea between 2009 and 2012 and were followed until 2015. Multivariable Cox proportional hazards regression models were performed.

RESULTS

During a mean follow-up of 5.2 ± 1.3 years, 30,813 individuals (0.86% of the total population) developed PD. Lower estimated glomerular filtration rate and a higher degree of proteinuria on a dipstick test were associated with higher incidence probability of PD (log-rank P < 0.001). In Cox regression models, chronic renal dysfunction graded by estimated glomerular filtration rate (mL/min/1.73 m² ) was associated with increased risk of PD after adjusting for potential confounding variables; hazard ratio (95% confidence interval) was 1.13 (1.10-1.17) for estimated glomerular filtration rate 60-90, 1.36 (1.31-1.42) for estimated glomerular filtration rate 30-60, and 1.47 (1.32-1.63) for estimated glomerular filtration rate <30 (P for trend <0.001). Proteinuria ≥1+ was also associated with increased risk of PD development (hazard ratio, 1.12; 95% confidence interval, 1.06-1.18). Coexistence of chronic kidney disease and proteinuria showed an increased hazard ratio of 1.33 (95% confidence interval, 1.23-1.45) for PD occurrence.

CONCLUSIONS

Our findings suggest that chronic renal dysfunction and dipstick-positive proteinuria may be independent risk factors for the development of PD in older adults. © 2019 International Parkinson and Movement Disorder Society.

Causal associations of blood lipids with risk of ischemic stroke and intracerebral hemorrhage in Chinese adults

Stroke is the second leading cause of death worldwide and accounts for >2 million deaths annually in China1,2. Ischemic stroke (IS) and intracerebral hemorrhage (ICH) account for an equal number of deaths in China, despite a fourfold greater incidence of IS1,2. Stroke incidence and ICH proportion are higher in China than in Western populations3-5, despite having a lower mean low-density lipoprotein cholesterol (LDL-C) concentration. Observational studies reported weaker positive associations of LDL-C with IS than with coronary heart disease (CHD)6,7, but LDL-C-lowering trials demonstrated similar risk reductions for IS and CHD8-10. Mendelian randomization studies of LDL-C and IS have reported conflicting results11-13, and concerns about the excess risks of ICH associated with lowering LDL-C14,15 may have prevented the more widespread use of statins in China. We examined the associations of biochemically measured lipids with stroke in a nested case-control study in the China Kadoorie Biobank (CKB) and compared the risks for both stroke types associated with equivalent differences in LDL-C in Mendelian randomization analyses. The results demonstrated positive associations of LDL-C with IS and equally strong inverse associations with ICH, which were confirmed by genetic analyses and LDL-C-lowering trials. Lowering LDL-C is still likely to have net benefit for the prevention of overall stroke and cardiovascular disease in China.

Foods, macronutrients and breast cancer risk in postmenopausal women: a large UK cohort

BACKGROUND

The role of diet in breast cancer aetiology is unclear; recent studies have suggested associations may differ by estrogen receptor status.

METHODS

Baseline diet was assessed in 2000-04 using a validated questionnaire in 691 571 postmenopausal UK women without previous cancer, who had not changed their diet recently. They were followed by record linkage to national cancer and death databases. Cox regression yielded adjusted relative risks for breast cancer for 10 food items and eight macronutrients, subdivided mostly into five categories of baseline intake. Trends in risk across the baseline categories were calculated, assigning re-measured intakes to allow for measurement error and changes in intake over time; P-values allowed for multiple testing.

RESULTS

Women aged 59.9 (standard deviation (SD 4.9)) years at baseline were followed for 12 (SD 3) years; 29 005 were diagnosed with invasive breast cancer. Alcohol intake had the strongest association with breast cancer incidence: relative risk (RR) 1.08 [99% confidence interval (CI) 1.05-1.11] per 10 g/day higher intake, P = 5.8 × 10-14. There were inverse associations with fruit: RR 0.94 (99% CI 0.92-0.97) per 100 g/day higher intake, P = 1.1 × 10-6, and dietary fibre: RR 0.91 (99% CI 0.87-0.96) per 5 g/day increase, P = 1.1 × 10-4. Fruit and fibre intakes were correlated (ρ = 0.62) and were greater among women who were not overweight, so residual confounding cannot be excluded. There was no heterogeneity for any association by estrogen receptor status.

CONCLUSIONS

By far the strongest association was between alcohol intake and an increased risk of breast cancer. Of the other 17 intakes examined, higher intakes of fruit and fibre were associated with lower risks of breast cancer, but it is unclear whether or not these associations are causal.

Utility of apolipoprotein measurements in predicting incident type 2 diabetes: A Chinese cohort study

BACKGROUND/PURPOSE

There is conflicting data regarding the utility of measuring apolipoproteins in addition to traditional lipid measures in risk assessment of cardiometabolic diseases. The aim of this study was to determine whether apolipoprotein measurements can improve the ability to predict the future development of type 2 diabetes beyond what is possible based on traditional type 2 diabetes risk factors and clinical routine lipid measurements.

METHODS

A total of 4,223 Chinese adults without diabetes were followed for a mean duration of 5.42 years. The hazard ratios (HRs) with 95% confidence intervals (CIs) derived from the Cox proportional hazards model were used to analyze the longitudinal associations of apolipoprotein B (apo B), apolipoprotein A-I (apo A-I), and the apo B/apo A-I ratio with the risk of type 2 diabetes. Further, the analysis of the area under receiver operating characteristics curves (AUC) was performed to test the predictive value of apolipoprotein measurements.

RESULTS

After adjusting for potential confounders, the HRs of diabetes consistently showed an increasing trend across both the apo B and the apo B/apo A-I ratio quartiles (p for trend = 0.004). In analyses of AUC, the predictive ability for type 2 diabetes risk for the apo B and the apo B/apo A-I ratio was superior to that of routine lipid and lipoprotein measurements.

CONCLUSION

Apolipoprotein measurements significantly predict diabetes risk in an Asian population. Furthermore, the predictive ability of apo B alone to detect diabetes was comparable with that of the apo B/apo A-I ratio and better than the routine lipid measurements.

Plasma hepcidin is associated with future risk of venous thromboembolism

Red cell distribution width (RDW) is associated with venous thromboembolism (VTE), but the underlying mechanism(s) is unclear. Iron deficiency is associated with high RDW, and studies suggest an association between iron deficiency and VTE. To assess whether iron deficiency is a risk factor for VTE that explains the association between RDW and VTE, we conducted a nested case-control study of 390 patients with VTE and 802 age- and sex-matched controls selected from the population-based cohort of the Tromsø Study. Physical measurements and blood samples were collected from 1994 to 1995. Logistic regression models were used to calculate odds ratios (ORs) with 95% confidence intervals (CIs) for VTE by RDW, hepcidin, and ferritin light chain (FtL). RDW was inversely associated with hepcidin, FtL, and hemoglobin. The risk of VTE increased linearly across categories of higher plasma hepcidin levels. Participants with hepcidin in the highest quartile had an OR for VTE of 1.32 (95% CI, 1.00-2.42), and those in the >90% percentile had an OR for VTE of 1.66 (95% CI, 1.14-2.42) compared with the reference group (quartiles 2 and 3). The risk estimates remained similar after adjustment for C-reactive protein. The risk of VTE increased by categories of higher RDW and was strengthened after inclusion of hepcidin and FtL in the multivariable model. Our findings reject the hypothesis that iron deficiency explains the association between RDW and VTE and suggest, in contrast, that high body iron levels might increase the risk of VTE.

Low HDL Cholesterol and High Risk of Autoimmune Disease: Two Population-Based Cohort Studies Including 117341 Individuals

BACKGROUND

HDL is quantitatively the most important lipoprotein in most species and mechanistic evidence points toward a role for HDL in normal immune function. We tested the hypothesis that concentrations of HDL cholesterol are associated with risk of autoimmune disease.

METHODS

From 2 studies of the general population-the Copenhagen General Population Study and the Copenhagen City Heart study-we included 107954 and 9387 individuals with baseline measurements of HDL cholesterol. These were followed with the national Danish Patient Registry from baseline in 2003-2015 or 1991-1994 through 2017, during which time 4078 and 1101 individuals developed autoimmune disease in the 2 studies.

RESULTS

In the Copenhagen General Population Study, compared to individuals with HDL cholesterol ≥2.0 mmol/L (77 mg/dL), the multifactorially adjusted hazard ratios for any autoimmune disease were 1.06 (95% CI, 0.94-1.19) for individuals with HDL cholesterol of 1.5-1.99 mmol/L (58-77 mg/dL), 1.18 (95% CI, 1.04-1.35) for individuals with HDL cholesterol of 1.0-1.49 mmol/L (39-58 mg/dL), and 1.84 (95% CI, 1.52-2.22) for individuals with HDL cholesterol <1.0 mmol/L (39 mg/dL) (P for trend <0.001). These results were similar when excluding events within 5 years of baseline, in women and men separately, for events at baseline, irrespective of low-grade inflammation or triglyceride concentrations, for the apolipoprotein A1 part of HDL, and for more restrictive end point definitions. Finally, the Copenhagen City Heart Study provided independent confirmation.

CONCLUSIONS

Low HDL cholesterol level is associated with high risk of autoimmune disease in individuals from the general population. Our observational findings cannot determine causality.

Dietary intake of marine n-3 polyunsaturated fatty acids and future risk of venous thromboembolism

BACKGROUND

Studies on the association between long-chained n-3 polyunsaturated fatty acids (n-3 PUFAs) and risk of venous thromboembolism (VTE) are conflicting, potentially due to challenges related to assessment of n-3 PUFA intake and changes in diet during follow-up.

OBJECTIVES

To investigate whether dietary intake of marine n-3 PUFAs was associated with risk of incident VTE in a population-based cohort with repeated assessments of n-3 PUFA intake.

METHODS

We recruited 21 970 participants (after excluding 7570 with incomplete data) from the fourth (1994-1995) and sixth (2007-2008) surveys of the Tromsø Study, and recorded incident VTEs up to 2016. Intake of n-3 PUFAs was computed from self-reported consumption of fat and lean fish, fish spread, and supplements. Cox proportional hazards regression models with n-3 PUFA intake as a time-varying variable were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for VTE across quartiles (Q) of n-3 PUFA intake.

RESULTS

There were 541 incident VTEs during follow-up. Compared to Q1, subjects in Q2-4 had 22%-26% lower risk of VTE (HR Q2 0.74, 95% CI 0.57-0.96; HR Q3 0.77, 95% CI 0.59-0.99; HR Q4 0.78, 95% CI 0.61-1.00). The association was most pronounced for provoked VTE, particularly provoked pulmonary embolism (PE), with risk estimates of 0.42 (95% CI 0.25-0.72), 0.40 (95% CI 0.23-0.68), and 0.61 (95% CI 0.38-0.96) for Q2-4, respectively.

CONCLUSIONS

Dietary intake of marine n-3 PUFAs was associated with a lower risk of VTE, particularly provoked PE. The association displayed a threshold pattern and suggested a protective effect of an n-3 PUFA intake ≥4.7 g/week.

Evaluation of Complementary and Integrative Health Approaches Among US Veterans with Musculoskeletal Pain Using Propensity Score Methods

Objectives

To examine the treatment effectiveness of complementary and integrative health approaches (CIH) on chronic pain using Propensity Score (PS) methods.

Design, Settings, and Participants

A retrospective cohort of 309,277 veterans with chronic musculoskeletal pain assessed over three years after initial diagnosis.

Methods

CIH exposure was defined as one or more clinical visits for massage, acupuncture, or chiropractic care. The treatment effect of CIH on self-rated pain intensity was examined using a longitudinal model. PS-matching and inverse probability of treatment weighting (IPTW) were used to account for potential selection and confounding biases.

Results

At baseline, veterans with (7,621) and without (301,656) CIH exposure differed significantly in 21 out of 35 covariates. During the follow-up period, on average CIH recipients had 0.83 (95% confidence interval [CI] = 0.77 to 0.89) points higher pain intensity ratings (range = 0-10) than nonrecipients. This apparent unfavorable effect size was reduced to 0.37 (95% CI = 0.28 to 0.45) after PS matching, 0.36 (95% CI = 0.29 to 0.44) with IPTW on the treated (IPTW-T) weighting, and diminished to null when integrating IPTW-T with PS matching (0.004, 95% CI = -0.09 to 0.10). An alternative IPTW model and conventional covariate adjustment appeared least powerful in terms of potential bias reduction. Sensitivity analyses restricting the follow-up period to one year after CIH initiation derived consistent results.

Conclusions

PS-based causal methods successfully eliminated baseline difference between exposure groups in all measured covariates, yet they did not detect a significant difference in the self-rated pain intensity outcome between veterans who received CIHs and those who did not during the follow-up period.

Low-Grade Inflammation in the Association between Mild-to-Moderate Hypertriglyceridemia and Risk of Acute Pancreatitis: A Study of More Than 115000 Individuals from the General Population

BACKGROUND

How mild-to-moderate hypertriglyceridemia (2-10 mmol/L; 177-886 mg/dL) potentially causes acute pancreatitis is unknown; however, cellular studies indicate that inflammation might be a driver of disease progression. We tested the hypotheses that (a) mild-to-moderate hypertriglyceridemia is associated with low-grade inflammation and that (b) the association between mild-to-moderate hypertriglyceridemia and risk of acute pancreatitis depends on low-grade inflammation.

METHODS

From the Copenhagen General Population Study and the Copenhagen City Heart Study, 117865 men and women 20-100+ years of age with measurements of nonfasting plasma triglycerides at baseline were followed prospectively for development of acute pancreatitis.

RESULTS

After multivariable adjustment, a 1 mmol/L (89 mg/dL) higher nonfasting triglyceride concentration was associated with 17% (95% CI, 16%-18%, P = 3 × 10^-17) higher plasma C-reactive protein (CRP) and a 4.2% (4.0%-4.4%, P = 6 × 10^-17) higher blood leukocyte count. Higher concentrations of nonfasting triglycerides were associated almost linearly with higher risk of acute pancreatitis (P for trend = 5 × 10^-6), with hazard ratios of 1.5 (95% CI, 0.9-2.5), 2.0 (95% CI, 1.1-3.6), 2.2 (95% CI, 1.0-4.7), 4.2 (95% CI, 1.6-11.5), and 7.7 (95% CI, 3.0-19.8) in individuals with nonfasting triglycerides of 1.00-1.99 mmol/L (89-176 mg/dL; 46% of the population), 2.00-2.99 mmol/L (177-265 mg/dL; 17%), 3.00-3.99 mmol/L (266-353 mg/dL; 6%), 4.00-4.99 mmol/L (354-442 mg/dL; 2%), and ≥5mmol/L(443 mg/dL; 2%), respectively, vs individuals with <1 mmol/L (89 mg/dL; 27%). The association with risk of acute pancreatitis appeared more pronounced in individuals with CRP of ≥1.39 mg/L (P for trend = 0.001) and leukocytes of ≥7 × 10⁹/L (P = 2 × 10^-4) than in those with CRP <1.39 mg/L (P = 0.03) and leukocytes <7 × 10⁹/L (P = 0.04); however, there was no formal evidence of statistical interaction (P = 0.38 for CRP and P = 0.41 for leukocytes).

CONCLUSIONS

Mild-to-moderate hypertriglyceridemia is associated with low-grade inflammation and higher risk of acute pancreatitis. The association between mild-to-moderate hypertriglyceridemia and risk of acute pancreatitis is possibly partly mediated by low-grade inflammation.

Baseline and longitudinal change in blood pressure and mortality in a Chinese cohort

BACKGROUND

A J-curve association has been demonstrated for blood pressure (BP) and all-cause mortality, but data on longitudinal change of BP and mortality in Chinese population are limited.

METHODS

We performed a retrospective cohort study to examine the association between BP (at baseline and longitudinal change) and risk of mortality in Yinzhou District, Ningbo, China, based on the Yinzhou Health Information System. At baseline, a total of 181 352 subjects aged over 18 years with at least one BP examination record were recruited through the Yinzhou Health Information System. The final analysis was restricted to 168 061 participants after exclusion of outliers of BP.

RESULTS

A U-shaped association was observed for BP at baseline and risk of total and cardiovascular mortality. When compared with normotensive participants, patients with hypotension (HRs=1.51, 95% CI 1.21 to 1.88) and stage 3 hypertension (1.28, 95% CI 1.09 to 1.50) had an increased risk of all-cause mortality. Relative to stable BP of normotension, having a rise in BP from normotension to hypertension or from prehypertension to hypertension both conferred an increased risk of total and cardiovascular mortality (total: 1.39 (95% 1.10 to 1.75) and 1.40 (95% 1.15 to 1.69); cardiovascular: 2.22 (95% CI 1.35 to 3.65) and 1.89 (95% CI 1.20 to 2.96), respectively).

CONCLUSIONS

Our findings emphasise that hypotension and stage 3 hypertension were associated with an increased risk of all-cause mortality. Longitudinal change from normotensive or prehypertensive levels to 140/90 mm Hg or higher could increase the risk of total and cardiovascular mortality.

Longitudinal change in blood pressure is associated with cardiovascular disease mortality in a Chinese cohort

BACKGROUND

A number of studies have demonstrated a J-shaped curve between blood pressure (BP) and all-cause mortality, but few studies have used longitudinal change in BP to study mortality in the Chinese population.

METHODS

We performed a 30-year follow-up study to examine the association between BP (at baseline and longitudinal change) and risk of mortality in the Linxian General Population Trial Cohort. At baseline, a total of 29 584 healthy adults were enrolled in the Linxian General Population Trial in 1985 and followed through to the end of 2014. The final analysis was restricted to 29 439 participants (55% women) after exclusion of outliers. We also examined the potential effects of BP trajectory patterns during the period of 1985-1999 on sequent risk of mortality. Adjusted Cox proportional hazards models were used to estimate HRs and 95% CIs.

RESULTS

Compared with participants with normal BP, patients with prehypertension, stage 1, stage 2 or stage 3 hypertension had an increased risk of all-cause mortality, with HRs of 1.09 (95% CI 1.05 to 1.14), 1.34 (95% CI 1.28 to 1.40), 1.69 (95% CI 1.60 to 1.79) and 2.14 (95% CI 2.01 to 2.28), respectively. Relative to stable BP of normotension, having a rise in BP from normotension to hypertension or from prehypertension to hypertension both conferred an increased risk of total and cardiovascular disease and stroke mortality (total: HRs 1.22 (95% CI 1.12 to 1.34) and 1.36 (95% CI 1.23 to 1.51); cardiovascular disease: HRs 1.42 (95% CI 1.17 to 1.73) and 1.55 (95% CI 1.24 to 1.93); stroke: HRs 2.29 (95% CI 1.88 to 2.80) and 2.61 (95% CI 2.11 to 3.24), respectively).

CONCLUSIONS

These findings emphasise that development of incident hypertension in middle age could increase the risk of total, cardiovascular disease and stroke mortality, and suggest that current BP targets could be revised.

TRIAL REGISTRATION NUMBER

NCT00342654;Post-results.

Repeated assessments of physical activity and risk of incident venous thromboembolism

Essentials It is debated whether physical activity influences the risk of venous thromboembolism. The association was explored accounting for fluctuations in physical activity over time. Overall and in the elderly, physical activity was associated with 23% and 30% lower risk. A moderate proportion of the association (14-36%) was mediated via body mass index. SUMMARY: Background Whether physical activity influences the risk of incident venous thromboembolism (VTE) remains controversial, potentially because of methodological challenges, such as regression dilution bias. Objectives To investigate whether physical activity was associated with VTE risk, and explore the role of body mass index (BMI) as a mediator in a population-based cohort with repeated assessments of physical activity. Methods Participants (n = 30 002) attending one or more surveys of the Tromsø Study 4-6 (1994-1995, 2001-2002, and 2007-2008) were included and categorized on the basis of weekly physical activity. Incident VTE was registered until 31 December 2016. Hazard ratios (HRs) were calculated by the use of time-varying Cox regression models. The Aalen additive hazard model was used to quantify the total, direct and indirect effects of physical activity. Results There were 531 incident VTEs during follow-up. Physical activity (≥ 1 per week) was associated with a lower risk of VTE (HR 0.77, 95% confidence interval [CI] 0.64-0.92) than being inactive. The effect was most pronounced for those aged ≥ 65 years (HR 0.70, 95% CI 0.55-0.88) and for provoked events (HR 0.66, 95% CI 0.50-0.89). The differences in absolute risk between active and inactive individuals were - 0.42 (95% CI - 0.73 to - 0.14) and - 1.59 (95% CI - 2.74 to - 0.52) events annually per 1000 individuals in the total and elderly populations, respectively. A moderate proportion of the association (14-36%) was mediated via BMI. Conclusion Our findings suggest that regular physical activity is associated with a lower risk of VTE, particularly in the elderly. The association occurred at a low weekly amount of physical activity, and was only partly mediated by BMI.

Lymphopenia and risk of infection and infection-related death in 98,344 individuals from a prospective Danish population-based study

BACKGROUND

Neutropenia increases the risk of infection, but it is unknown if this also applies to lymphopenia. We therefore tested the hypotheses that lymphopenia is associated with increased risk of infection and infection-related death in the general population.

METHODS AND FINDINGS

Of the invited 220,424 individuals, 99,191 attended examination. We analyzed 98,344 individuals from the Copenhagen General Population Study (Denmark), examined from November 25, 2003, to July 9, 2013, and with available blood lymphocyte count at date of examination. During a median of 6 years of follow-up, they developed 8,401 infections and experienced 1,045 infection-related deaths. Due to the completeness of the Danish civil and health registries, none of the 98,344 individuals were lost to follow-up, and those emigrating (n = 385) or dying (n = 5,636) had their follow-up truncated at the day of emigration or death. At date of examination, mean age was 58 years, and 44,181 (44.9%) were men. Individuals with lymphopenia (lymphocyte count < 1.1 × 109/l, n = 2,352) compared to those with lymphocytes in the reference range (1.1-3.7 × 109/l, n = 93,538) had multivariable-adjusted hazard ratios of 1.41 (95% CI 1.28-1.56) for any infection, 1.31 (1.14-1.52) for pneumonia, 1.44 (1.15-1.79) for skin infection, 1.26 (1.02-1.56) for urinary tract infection, 1.51 (1.21-1.89) for sepsis, 1.38 (1.01-1.88) for diarrheal disease, 2.15 (1.16-3.98) for endocarditis, and 2.26 (1.21-4.24) for other infections. The corresponding hazard ratio for infection-related death was 1.70 (95% CI 1.37-2.10). Analyses were adjusted for age, sex, smoking status, cumulative smoking, alcohol intake, body mass index, plasma C-reactive protein, blood neutrophil count, recent infection, Charlson comorbidity index, autoimmune diseases, medication use, and immunodeficiency/hematologic disease. The findings were robust in all stratified analyses and also when including only events later than 2 years after first examination. However, due to the observational design, the study cannot address questions of causality, and our analyses might theoretically have been affected by residual confounding and reverse causation. In principle, fluctuating lymphocyte counts over time might also have influenced analyses, but lymphocyte counts in 5,181 individuals measured 10 years after first examination showed a regression dilution ratio of 0.68.

CONCLUSIONS

Lymphopenia was associated with increased risk of hospitalization with infection and increased risk of infection-related death in the general population. Notably, causality cannot be deduced from our data.

Increased plasma trimethylamine-N-oxide is associated with incident atrial fibrillation

BACKGROUND

Plasma trimethylamine-N-oxide (TMAO) is associated with cardiovascular disease; however specific relationships with cardiac arrhythmias are unknown. We evaluated the association between plasma TMAO and incident atrial fibrillation (AF).

METHODS

Risk associations were explored among 3797 patients with suspected stable angina in the Western Norway Coronary Angiography Cohort (WECAC) and verified in 3143 elderly participants in the community-based Hordaland Health Study (HUSK). Information on endpoints was obtained from nationwide registries.

RESULTS

Median follow-up was 7.3 and 10.8 years in the WECAC and HUSK cohorts, respectively, and 412 (10.9%) and 484 (15.4%) subjects were registered with incident AF. The age and gender adjusted HRs were 1.16, 95% CI 1.05-1.28 and 1.10, 95% CI 1.004-1.19 per 1 SD increase in log-transformed plasma TMAO. Adjusting for hypertension, BMI, smoking, diabetes, or intake of total choline, a TMAO precursor, did not materially influence the risk associations. Among patients in WECAC, further extensive adjustment for other AF risk factors yielded similar results. Adding TMAO to traditional AF risk factors (age, gender, hypertension, BMI, smoking and diabetes) yielded a continuous net reclassification improvement of 0.108, 95% CI 0.015-0.202 and 0.139, 95% CI 0.042-0.235.

CONCLUSIONS

Plasma TMAO was associated with and improved reclassification of incident AF in two independent Norwegian cohorts with long-term follow-up. The relationship was independent of traditional AF risk factors, as well as of dietary choline intake. Our findings motivate further studies to explore endogenous metabolic factors influencing the relationship between TMAO and cardiovascular disease.

Environmental toxic metal contaminants and risk of cardiovascular disease: systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis of epidemiological studies investigating the association of arsenic, lead, cadmium, mercury, and copper with cardiovascular disease.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, and Web of Science searched up to December 2017.

REVIEW METHODS

Studies reporting risk estimates for total cardiovascular disease, coronary heart disease, and stroke for levels of arsenic, lead, cadmium, mercury, or copper were included. Two investigators independently extracted information on study characteristics and outcomes in accordance with PRISMA and MOOSE guidelines. Relative risks were standardised to a common scale and pooled across studies for each marker using random effects meta-analyses.

RESULTS

The review identified 37 unique studies comprising 348 259 non-overlapping participants, with 13 033 coronary heart disease, 4205 stroke, and 15 274 cardiovascular disease outcomes in aggregate. Comparing top versus bottom thirds of baseline levels, pooled relative risks for arsenic and lead were 1.30 (95% confidence interval 1.04 to 1.63) and 1.43 (1.16 to 1.76) for cardiovascular disease, 1.23 (1.04 to 1.45) and 1.85 (1.27 to 2.69) for coronary heart disease, and 1.15 (0.92 to 1.43) and 1.63 (1.14 to 2.34) for stroke. Relative risks for cadmium and copper were 1.33 (1.09 to 1.64) and 1.81 (1.05 to 3.11) for cardiovascular disease, 1.29 (0.98 to 1.71) and 2.22 (1.31 to 3.74) for coronary heart disease, and 1.72 (1.29 to 2.28) and 1.29 (0.77 to 2.17) for stroke. Mercury had no distinctive association with cardiovascular outcomes. There was a linear dose-response relation for arsenic, lead, and cadmium with cardiovascular disease outcomes.

CONCLUSION

Exposure to arsenic, lead, cadmium, and copper is associated with an increased risk of cardiovascular disease and coronary heart disease. Mercury is not associated with cardiovascular risk. These findings reinforce the importance of environmental toxic metals in cardiovascular risk, beyond the roles of conventional behavioural risk factors.

Metabolic syndrome status over 2 years predicts incident chronic kidney disease in mid-life adults: a 10-year prospective cohort study

We investigated whether changes in MetS status over two years modify the 10-year risk of CKD and proteinuria. A prospective cohort study was conducted in 7,251 subjects without CKD at baseline. We categorized subjects according to MetS status over two years: non-MetS (no MetS at either visit), intermittent MetS (positive for MetS at one assessment), and persistent MetS (positive for MetS at two assessments). The hazard ratio (HR) of new-onset CKD over 10-year was calculated using Cox models. During the 10-year follow-up period, 923 (12.7%) developed CKD. Compared to the non-MetS group, the fully adjusted HR for new-onset CKD was the highest in the persistent MetS group (HR, 1.53; 95% CI, 1.23-1.90), followed by the intermittent MetS group (HR, 1.29; 95% CI, 1.04-1.59) (P for trend <0.001). The HR for developing proteinuria was 1.79 (95% CI, 1.15-2.79) in the persistent MetS group and 0.70 (95% CI, 0.42-1.19) in the intermittent MetS group when the non-MetS group was considered as the reference group. Temporal changes in MetS status over two years influenced the 10-year risk of incident CKD and proteinuria. Our findings suggest that monitoring and strictly controlling MetS are important in preventing renal function decline.

Discharge home health services referral and 30-day all-cause readmission in older adults with heart failure

INTRODUCTION

Heart failure (HF) is the leading cause of hospital readmission. Medicare home health services provide intermittent skilled nursing care to homebound Medicare beneficiaries. We examined whether discharge home health referral is associated with a lower risk of 30-day all-cause readmission in HF.

MATERIAL AND METHODS

Of the 8049 Medicare beneficiaries hospitalized for acute HF and discharged alive from 106 Alabama hospitals, 6406 (76%) patients were not admitted from nursing homes and were discharged home without discharge hospice referrals. Of these, 1369 (21%) received a discharge home health referral. Using propensity scores for home health referral, we assembled a matched cohort of 1253 pairs of patients receiving and not receiving home health referrals, balanced on 33 baseline characteristics.

RESULTS

The 2506 matched patients had a mean age of 78 years, 61% were women, and 27% were African American. Thirty-day all-cause readmission occurred in 28% and 19% of matched patients receiving and not receiving home health referrals, respectively (hazard ratio (HR) = 1.52; 95% confidence interval (CI): 1.29-1.80; p < 0.001). Home health referral was also associated with a higher risk of 30-day all-cause mortality (HR = 2.32; 95% CI: 1.58-3.41; p < 0.001) but not with 30-day HF readmission (HR = 1.28; 95% CI: 0.99-1.64; p = 0.056). HRs (95% CIs) for 1-year all-cause readmission, all-cause mortality, and HF readmission are 1.24 (1.13-1.36; p < 0.001), 1.37 (1.20-1.57; p < 0.001) and 1.09 (0.95-1.24; p = 0.216), respectively.

CONCLUSIONS

Hospitalized HF patients who received discharge home health services referral had a higher risk of 30-day and 1-year all-cause readmission and all-cause mortality, but not of HF readmission.

Menopause Characteristics, Total Reproductive Years, and Risk of Cardiovascular Disease Among Chinese Women

Supplemental Digital Content is available in the text.

Background—

Previous studies, mostly of Western women, have reported inconsistent findings on the association of menopause characteristics (status, age, and time since menopause) and total reproductive years with risk of cardiovascular disease (CVD).

Methods and Results—

The China Kadoorie Biobank recruited 302 632 women in 2004 to 2008 from 10 regions across China. During 9-year follow-up, 19 393 incident cases of stroke, 18 611 of ischemic heart disease, and 4978 CVD deaths occurred. Cox regression yielded adjusted hazard ratios relating each menopause characteristic and total reproductive years to CVD risk. Among 274 233 women with no prior CVD at baseline, 134 010 were naturally postmenopausal women (mean [SD] age at menopause of 48.6 [4.0] years and total reproductive years 32.7 [4.4]). Compared with premenopausal women, naturally peri- or postmenopausal women were at a higher risk of either fatal or nonfatal CVD. Among women who had had menopause, inverse associations were observed between age at menopause and risks of CVD mortality, incident ischemic heart disease, stroke, and subtypes of stroke, with 1.5% higher risk of CVD death (P<0.001), 0.7% for incident ischemic heart disease (P=0.002), and 0.5% for incident stroke (P=0.02) for every 1 year lower age at menopause. Compared with women who had menopause at age 48 to 50 years, lower age at menopause (ie, <43 years) was associated with 14% higher risk of CVD death and 6% higher risks of both incident ischemic heart disease and stroke. Higher risks of both fatal and nonfatal CVD were also found in women with 5 to 10, 10 to 15, 15 to 20, or >20 years since menopause compared with <5 years since menopause. Total reproductive years were inversely associated with risks of both fatal and nonfatal CVD, with 1.4% lower risk of CVD death per additional reproductive year (P<0.001).

Conclusions—

Women with younger age at menopause, longer time since menopause, or fewer total reproductive years had a higher risk of CVD.

Body-mass index, blood pressure, and cause-specific mortality in India: a prospective cohort study of 500 810 adults

BACKGROUND

The association between cause-specific mortality and body-mass index (BMI) has been studied mainly in high-income countries. We investigated the relations between BMI, systolic blood pressure, and mortality in India.

METHODS

Men and women aged 35 years or older were recruited into a prospective study from the general population in Chennai, India between Jan 1, 1998, and Dec 31, 2001. Participants were interviewed (data collected included age, sex, education, socioeconomic status, medical history, tobacco smoking, and alcohol intake) and measured (height, weight, and blood pressure). Deaths were identified by linkage to Chennai city mortality records and through active surveillance by household visits from trained graduate non-medical fieldworkers. After the baseline survey, households were visited once in 2002-05, then biennially until 2015. During these repeat visits, structured narratives of any deaths that took place before March 31, 2015, were recorded for physician coding. During 2013-14, a random sample of participants was also resurveyed as per baseline to assess long-term variability in systolic blood pressure and BMI. Cox regression (standardised for tobacco, alcohol, and social factors) was used to relate mortality rate ratios (RRs) at ages 35-69 years to systolic blood pressure, BMI, or BMI adjusted for usual systolic blood pressure.

FINDINGS

500 810 participants were recruited. After exclusion of those with chronic disease or incomplete data, 414 746 participants aged 35-69 years (mean 46 [SD 9]; 45% women) remained. At recruitment, mean systolic blood pressure was 127 mm Hg (SD 15), and mean BMI was 23·2 kg/m2 (SD 3·8). Correlations of resurvey and baseline measurements were 0·50 for systolic blood pressure and 0·88 for BMI. Low BMI was strongly associated with poverty, tobacco, and alcohol. Of the 29 519 deaths at ages 35-69 years, the cause was vascular for 14 935 deaths (12 504 cardiac, 1881 stroke, and 550 other). Vascular mortality was strongly associated with systolic blood pressure: RRs per 20 mm Hg increase in usual systolic blood pressure were 2·45 (95% CI 2·16-2·78) for stroke mortality, 1·74 (1·64-1·84) for cardiac mortality, and 1·84 (1·75-1·94) for all vascular mortality. Although BMI strongly affected systolic blood pressure (an increase of about 1 mm Hg per kg/m2) and diabetes prevalence, BMI was little related to cardiac or stroke mortality, with only small excesses even for grade 1 obesity (ie, BMIs of 30·0-35·0 kg/m2). After additional adjustment for usual systolic blood pressure, BMI was inversely related to cardiac and stroke mortality throughout the range 15·0-30·0 kg/m2: when underweight participants (ie, BMI 15·0-18·5 kg/m2) were compared with overweight participants (ie, BMI 25·0-30·0 kg/m2), the blood-pressure-adjusted RR was 1·28 (95% CI 1·20-1·38) for cardiac mortality and 1·46 (1·22-1·73) for stroke mortality.

INTERPRETATION

In this South Asian population, BMI was little associated with vascular mortality, even though increased BMI is associated with increased systolic blood pressure, which in turn is associated with increased vascular mortality. Hence, some close correlates of below-average BMI must have important adverse effects, which could be of relevance in all populations.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK.

Hyperhomocysteinemia and Risk of First Venous Thrombosis: The Influence of (Unmeasured) Confounding Factors

Meta-analyses have reported a 2- to 3-fold increased risk of venous thrombosis (VT) in individuals with hyperhomocysteinemia. However, confounding factors were generally not considered. In contrast, randomized trials of homocysteine-lowering therapy and VT risk have been negative. We investigated whether hyperhomocysteinemia was associated with VT in the Multiple Environmental and Genetic Assessment of Risk Factors for Venous Thrombosis (MEGA) case-control study (1999-2004) from the Netherlands (1,689 cases and 1,726 controls), taking into account measured and unmeasured confounders. We compared patients with population controls to estimate odds ratios using unconditional logistic regression and adjusted for various potential confounders. We matched patients to their partners to additionally adjust for unmeasured confounders (e.g., lifestyle factors) using conditional logistic regression. We found that elevated homocysteine concentrations were not associated with an increased risk for VT when comparing patients with population controls, either as a continuous variable (odds ratio = 1.00, 95% confidence interval: 0.99, 1.01), in terms of 0.7-mg/L increase (odds ratio = 0.99, 95% confidence interval: 0.93, 1.05), or within different homocysteine categories. We obtained similar results when patients were compared with their partners. Stratification by sex, deep vein thrombosis, pulmonary embolism, provoked VT, and unprovoked VT also provided no evidence of an association. In conclusion, after extensive adjustments for confounding, hyperhomocysteinemia was not associated with an increased risk of venous thrombosis in this study.

Adiposity and risk of ischaemic and haemorrhagic stroke in 0·5 million Chinese men and women: a prospective cohort study

BACKGROUND

China has high stroke rates despite the population being relatively lean. Uncertainty persists about the relevance of adiposity to risk of stroke types. We aimed to assess the associations of adiposity with incidence of stroke types and effect mediation by blood pressure in Chinese men and women.

METHODS

The China Kadoorie Biobank enrolled 512 891 adults aged 30-79 years from ten areas (five urban and five rural) during 2004-08. During a median 9 years (IQR 8-10) of follow-up, 32 448 strokes (about 90% confirmed by neuroimaging) were recorded among 489 301 participants without previous cardiovascular disease. Cox regression analysis was used to produce adjusted hazard ratios (HRs) for ischaemic stroke (n=25 210) and intracerebral haemorrhage (n=5380) associated with adiposity.

FINDINGS

Mean baseline body-mass index (BMI) was 23·6 kg/m² (SD 3·2), and 331 723 (67·8%) participants had a BMI of less than 25 kg/m². Throughout the range examined (mean 17·1 kg/m² [SD 0·9] to 31·7 kg/m² [2·0]), each 5 kg/m² higher BMI was associated with 8·3 mm Hg (SE 0·04) higher systolic blood pressure. BMI was positively associated with ischaemic stroke, with an HR of 1·30 (95% CI 1·28-1·33 per 5 kg/m² higher BMI), which was generally consistent with that predicted by equivalent differences in systolic blood pressure (1·25 [1·24-1·26]). The HR for intracerebral haemorrhage (1·11 [1·07-1·16] per 5 kg/m² higher BMI) was less extreme, and much weaker than that predicted by the corresponding difference in systolic blood pressure (1·48 [1·46-1·50]). Other adiposity measures showed similar associations with stroke types. After adjustment for usual systolic blood pressure, the positive associations with ischaemic stroke were attenuated (1·05 [1·03-1·07] per 5 kg/m² higher BMI); for intracerebral haemorrhage, they were reversed (0·73 [0·70-0·77]). High adiposity (BMI >23 kg/m²) accounted for 14·7% of total stroke (16·5% of ischaemic stroke and 6·7% of intracerebral haemorrhage).

INTERPRETATION

In Chinese adults, adiposity was strongly positively associated with ischaemic stroke, chiefly through its effect on blood pressure. For intracerebral haemorrhage, leanness, either per se or through some other factor (or factors), might increase risk, offsetting the protective effects of lower blood pressure.

FUNDING

UK Wellcome Trust, UK Medical Research Council, British Heart Foundation, Cancer Research UK, Kadoorie Charitable Foundation, Chinese Ministry of Science and Technology, Chinese National Natural Science Foundation.

Age-specific association between blood pressure and vascular and non-vascular chronic diseases in 0·5 million adults in China: a prospective cohort study

BACKGROUND

The age-specific association between blood pressure and vascular disease has been studied mostly in high-income countries, and before the widespread use of brain imaging for diagnosis of the main stroke types (ischaemic stroke and intracerebral haemorrhage). We aimed to investigate this relationship among adults in China.

METHODS

512 891 adults (59% women) aged 30-79 years were recruited into a prospective study from ten areas of China between June 25, 2004, and July 15, 2008. Participants attended assessment centres where they were interviewed about demographic and lifestyle characteristics, and their blood pressure, height, and weight were measured. Incident disease was identified through linkage to local mortality records, chronic disease registries, and claims to the national health insurance system. We used Cox regression analysis to produce adjusted hazard ratios (HRs) relating systolic blood pressure to disease incidence. HRs were corrected for regression dilution to estimate associations with long-term average (usual) systolic blood pressure.

FINDINGS

During a median follow-up of 9 years (IQR 8-10), there were 88 105 incident vascular and non-vascular chronic disease events (about 90% of strokes events were diagnosed using brain imaging). At ages 40-79 years (mean age at event 64 years [SD 9]), usual systolic blood pressure was continuously and positively associated with incident major vascular disease throughout the range 120-180 mm Hg: each 10 mm Hg higher usual systolic blood pressure was associated with an approximately 30% higher risk of ischaemic heart disease (HR 1·31 [95% CI 1·28-1·34]) and ischaemic stroke (1·30 [1·29-1·31]), but the association with intracerebral haemorrhage was about twice as steep (1·68 [1·65-1·71]). HRs for vascular disease were twice as steep at ages 40-49 years than at ages 70-79 years. Usual systolic blood pressure was also positively associated with incident chronic kidney disease (1·40 [1·35-1·44]) and diabetes (1·14 [1·12-1·15]). About half of all vascular deaths in China were attributable to elevated blood pressure (ie, systolic blood pressure >120 mm Hg), accounting for approximately 1 million deaths (<80 years of age) annually.

INTERPRETATION

Among adults in China, systolic blood pressure was continuously related to major vascular disease with no evidence of a threshold down to 120 mm Hg. Unlike previous studies in high-income countries, blood pressure was more strongly associated with intracerebral haemorrhage than with ischaemic stroke. Even small reductions in mean blood pressure at a population level could be expected to have a major impact on vascular morbidity and mortality.

FUNDING

UK Wellcome Trust, UK Medical Research Council, British Heart Foundation, Cancer Research UK, Kadoorie Charitable Foundation, Chinese Ministry of Science and Technology, and the National Science Foundation of China.

Plasma cystathionine and risk of acute myocardial infarction among patients with coronary heart disease: Results from two independent cohorts

BACKGROUND

Cystathionine is a thio-ether and a metabolite formed from homocysteine during transsulfuration. Elevated plasma cystathionine levels are reported in patients with cardiovascular disease; however prospective relationships with acute myocardial infarction (AMI) are unknown. We investigated associations between plasma cystathionine and AMI among patients with suspected and/or verified coronary heart disease (CHD).

METHODS

Subjects from two independent cohort studies, the Western Norway Coronary Angiography Cohort (WECAC) (3033 patients with stable angina pectoris; 263 events within 4.8 years of median follow-up) and the Norwegian Vitamin Trial (NORVIT) (3670 patients with AMI; 683 events within 3.2 years of median follow-up) were included.

RESULTS

In both cohorts, plasma cystathionine was associated with several traditional CHD risk factors (P < 0.001). Comparing the cystathionine quartile 4 to 1, age and gender adjusted hazard ratios (95% confidence intervals) for AMI were 2.08 (1.43-3.03) and 1.41 (1.12-1.76) in WECAC and NORVIT, respectively. Additional adjustment for traditional risk factors slightly attenuated the risk estimates, which were generally stronger in both cohorts among non-smokers, patients with higher age, and lower BMI or PLP status (P-interaction ≤ 0.04). Risk associations also tended to be stronger in patients not treated with B-vitamins. Additionally, in a subset of 80 WECAC patients, plasma cystathionine associated strongly negatively with glutathione, an important antioxidant and positively with lanthionine, a marker of H₂S production (P < 0.001).

CONCLUSIONS

Plasma cystathionine is associated with increased risk of AMI among patients with either suspected or verified coronary heart disease, and is possibly related to altered redox homeostasis.

Systolic Blood Pressure and Outcomes in Patients With Heart Failure With Preserved Ejection Fraction

IMPORTANCE

Lower systolic blood pressure (SBP) levels are associated with poor outcomes in patients with heart failure. Less is known about this association in heart failure with preserved ejection fraction (HFpEF).

OBJECTIVE

To determine the associations of SBP levels with mortality and other outcomes in HFpEF.

DESIGN, SETTING, AND PARTICIPANTS

A propensity score-matched observational study of the Medicare-linked Organized Program to Initiate Lifesaving Treatment in Hospitalized Patients with Heart Failure (OPTIMIZE-HF) registry included 25 354 patients who were discharged alive; 8873 (35.0%) had an ejection fraction of at least 50%, and of these, 3915 (44.1%) had stable SBP levels (≤20 mm Hg admission to discharge variation). Data were collected from 259 hospitals in 48 states between March 1, 2003, and December 31, 2004. Data were analyzed from March 1, 2003, to December 31, 2008.

EXPOSURE

Discharge SBP levels less than 120 mm Hg. A total of 1076 of 3915 (27.5%) had SBP levels less than 120 mm Hg, of whom 901 (83.7%) were matched by propensity scores with 901 patients with SBP levels of 120 mm Hg or greater who were balanced on 58 baseline characteristics.

MAIN OUTCOMES AND MEASURES

Thirty-day, 1-year, and overall all-cause mortality and heart failure readmission through December 31, 2008.

RESULTS

The 1802 matched patients had a mean (SD) age of 79 (10) years; 1147 (63.7%) were women, and 134 (7.4%) were African American. Thirty-day all-cause mortality occurred in 91 (10%) and 45 (5%) of matched patients with discharge SBP of less than 120 mm Hg vs 120 mm Hg or greater, respectively (hazard ratio [HR], 2.07; 95% CI, 1.45-2.95; P < .001). Systolic blood pressure level less than 120 mm Hg was also associated with a higher risk of mortality at 1 year (39% vs 31%; HR, 1.36; 95% CI, 1.16-1.59; P < .001) and during a median follow-up of 2.1 (overall 6) years (HR, 1.17; 95% CI, 1.05-1.30; P = .005). Systolic blood pressure level less than 120 mm Hg was associated with a higher risk of heart failure readmission at 30 days (HR, 1.47; 95% CI, 1.08-2.01; P = .02) but not at 1 or 6 years. Hazard ratios for the combined end point of heart failure readmission or all-cause mortality associated with SBP level less than 120 mm at 30 days, 1 year, and overall were 1.71 (95% CI, 1.34-2.18; P < .001), 1.21 (95% CI, 1.07-1.38; P = .004), and 1.12 (95% CI, 1.01-1.24; P = .03), respectively.

CONCLUSIONS AND RELEVANCE

Among hospitalized patients with HFpEF, an SBP level less than 120 mm Hg is significantly associated with poor outcomes. Future studies need to prospectively evaluate optimal SBP treatment goals in patients with HFpEF.

Digoxin use and lower risk of 30-day all-cause readmission in older patients with heart failure and reduced ejection fraction receiving β-blockers

BACKGROUND

Digoxin use has been associated with a lower risk of 30-day all-cause admission and readmission in patients with heart failure and reduced ejection fraction (HFrEF).

HYPOTHESIS

Digoxin use will be associated with improved outcomes in patients with HFrEF receiving β-blockers.

METHODS

Of the 3076 hospitalized Medicare beneficiaries with HFrEF (EF <45%), 1046 received a discharge prescription for β-blockers, of which 634 were not on digoxin. Of the 634, 204 received a new discharge prescription for digoxin. Propensity scores for digoxin use, estimated for each of the 634 patients, were used to assemble a matched cohort of 167 pairs of patients receiving and not receiving digoxin, balanced on 30 baseline characteristics. Matched patients (n = 334) had a mean age of 74 years and were 46% female and 30% African American.

RESULTS

30-day all-cause readmission occurred in 15% and 27% of those receiving and not receiving digoxin, respectively (hazard ratio [HR]: 0.51, 95% confidence interval [CI]: 0.31-0.83, P = 0.007). This beneficial association persisted during 4 years of follow-up (HR: 0.72, 95% CI: 0.57-0.92, P = 0.008). Digoxin use was also associated with a lower risk of the combined endpoint of all-cause readmission or all-cause mortality at 30 days (HR: 0.54, 95% CI: 0.34-0.86, P = 0.009) and at 4 years (HR: 0.76, 95% CI: 0.61-0.96, P = 0.020).

CONCLUSIONS

In hospitalized patients with HFrEF receiving β-blockers, digoxin use was associated with a lower risk of 30-day all-cause readmission but not mortality, which persisted during longer follow-up.

One-hour glucose value as a long-term predictor of cardiovascular morbidity and mortality: the Malmö Preventive Project

OBJECTIVE

To examine the predictive capability of a 1-h vs 2-h postload glucose value for cardiovascular morbidity and mortality.

DESIGN

Prospective, population-based cohort study (Malmö Preventive Project) with subject inclusion 1974-1992.

METHODS

4934 men without known diabetes and cardiovascular disease, who had blood glucose (BG) measured at 0, 20, 40, 60, 90 and 120 min during an OGTT (30 g glucose per m² body surface area), were followed for 27 years. Data on cardiovascular events and death were obtained through national and local registries. Predictive capabilities of fasting BG (FBG) and glucose values obtained during OGTT alone and added to a clinical prediction model comprising traditional cardiovascular risk factors were assessed using Harrell's concordance index (C-index) and integrated discrimination improvement (IDI).

RESULTS

Median age was 48 (25th-75th percentile: 48-49) years and mean FBG 4.6 ± 0.6 mmol/L. FBG and 2-h postload BG did not independently predict cardiovascular events or death. Conversely, 1-h postload BG predicted cardiovascular morbidity and mortality and remained an independent predictor of cardiovascular death (HR: 1.09, 95% CI: 1.01-1.17, P = 0.02) and all-cause mortality (HR: 1.10, 95% CI: 1.05-1.16, P < 0.0001) after adjusting for various traditional risk factors. Clinical risk factors with added 1-h postload BG performed better than clinical risk factors alone, in predicting cardiovascular death (likelihood-ratio test, P = 0.02) and all-cause mortality (likelihood-ratio test, P = 0.0001; significant IDI, P = 0.0003).

CONCLUSION

Among men without known diabetes, addition of 1-h BG, but not FBG or 2-h BG, to clinical risk factors provided incremental prognostic yield for prediction of cardiovascular death and all-cause mortality.

Associations of General and Central Adiposity With Incident Diabetes in Chinese Men and Women

OBJECTIVE

We assess associations of general and central adiposity in middle age and of young adulthood adiposity with incident diabetes in adult Chinese and estimate the associated population burden of diabetes.

RESEARCH DESIGN AND METHODS

The prospective China Kadoorie Biobank enrolled 512,891 adults 30-79 years of age from 10 localities across China during 2004-2008. During 9.2 years of follow-up, 13,416 cases of diabetes were recorded among 482,589 participants without diabetes at baseline. Cox regression yielded adjusted hazard ratios (HRs) for incident diabetes associated with measures of general (e.g., BMI and BMI at 25 years) and central (e.g., waist circumference [WC]) adiposity.

RESULTS

The mean (SD) BMI was 23.6 kg/m² (3.4 kg/m²), and 3.8% had a BMI ≥30 kg/m². Throughout the range examined (19-32 kg/m²), BMI showed a positive log-linear relationship with diabetes, with adjusted HRs per SD higher usual BMI greater in men (1.98; 95% CI 1.93-2.04) than in women (1.77; 1.73-1.81) (P for heterogeneity <0.001). For WC, HRs per SD were 2.13 (95% CI 2.07-2.19) in men and 1.91 (1.87-1.95) in women (P for heterogeneity <0.001). Mutual adjustment attenuated these associations, especially those of BMI. BMI at age 25 years was weakly positively associated with diabetes (men HR 1.09 [95% CI 1.05-1.12]; women 1.04 [1.02-1.07] per SD), which was reversed after adjustment for baseline BMI. In China, the increase in adiposity accounted for ∼50% of the increase in diabetes burden since 1980.

CONCLUSIONS

Among relatively lean Chinese adults, higher adiposity-general and central-was strongly positively associated with the risk of incident diabetes. The predicted continuing increase in adiposity in China foreshadows escalating rates of diabetes.

American Heart Association's Life's Simple 7 at Middle Age and Prognosis After Myocardial Infarction in Later Life

Background

The American Heart Association recommends focusing on 7 health factors (Life's Simple 7) for primordial prevention of cardiovascular health. However, whether greater adherence to Life's Simple 7 in midlife improves prognosis after myocardial infarction (MI) in later life is unknown.

Methods and Results

In 1277 participants who developed MI during the ARIC (Atherosclerosis Risk in Communities) Study follow‐up, a 14‐point score of Life's Simple 7 was constructed according to the status (2 points for ideal, 1 point for intermediate, and 0 points for poor) of each of 7 factors (smoking, adiposity, physical activity, diet, total cholesterol, blood pressure, and fasting glucose) at baseline (1987–1989). Hazard ratios for composite and individual adverse outcomes of all‐cause mortality, cardiovascular mortality, recurrent MI, heart failure, and stroke were calculated according to Life's Simple 7 score. During a median follow‐up of 3.3 years, 918 participants (72%) had subsequent adverse outcomes after MI. Life's Simple 7 score at middle age was inversely associated with adverse outcomes after MI (adjusted hazard ratios of composite outcome, 0.57 [95% confidence interval, 0.39–0.84] if score is ≥10, 0.78 [95% confidence interval, 0.57–1.07] if score is 7–9, and 0.82 [95% confidence interval, 0.60–1.11] if score is 4–6 versus ≤3). The association was largely independent of access to care and MI severity. Individual factors related to better prognosis after MI were ideal nonsmoking, body mass index, blood pressure, and fasting glucose.

Conclusions

Optimal Life's Simple 7 at middle age was associated with better prognosis after MI in later life. Our findings suggest a secondary prevention benefit of having better cardiovascular health status in midlife.

Prognostic utility of estimated albumin excretion rate in chronic kidney disease: results from the Study of Heart and Renal Protection

Background

Estimated albumin excretion rate (eAER) provides a better estimate of 24-h albuminuria than albumin:creatinine ratio (ACR). However, whether eAER is superior to ACR in predicting end-stage renal disease (ESRD), vascular events (VEs) or death is uncertain.

Methods

The prognostic utility of ACR and eAER (estimated from ACR, sex, age and race) to predict mortality, ESRD and VEs was compared using Cox proportional hazards regression among 5552 participants with chronic kidney disease in the Study of Heart and Renal Protection, who were not on dialysis at baseline.

Results

During a median follow-up of 4.8 years, 1959 participants developed ESRD, 1204 had a VE and 1130 died (641 from a non-vascular, 369 from a vascular and 120 from an unknown cause). After adjustment for age, sex and eGFR, both ACR and eAER were strongly and similarly associated with ESRD risk. The average relative risk (RR) per 10-fold higher level was 2.70 (95% confidence interval 2.45-2.98) for ACR and 2.67 (2.43-2.94) for eAER. Neither ACR nor eAER provided any additional prognostic information for ESRD risk over and above the other. For VEs, there were modest positive associations between both ACR and eAER and risk [adjusted RR per 10-fold higher level 1.37 (1.22-1.53) for ACR and 1.36 (1.22-1.52) for eAER]. Again, neither measure added prognostic information over and above the other. Similar results were observed when ACR and eAER were related to vascular mortality [RR per 10-fold higher level: 1.64 (1.33-2.03) and 1.62 (1.32-2.00), respectively] or to non-vascular mortality [1.53 (1.31-1.79) and 1.50 (1.29-1.76), respectively].

Conclusions

In this study, eAER did not improve risk prediction of ESRD, VEs or mortality.

Dietary assessment in UK Biobank: an evaluation of the performance of the touchscreen dietary questionnaire

UK Biobank is an open access prospective cohort of 500 000 men and women. Information on the frequency of consumption of main foods was collected at recruitment with a touchscreen questionnaire; prior to examining the associations between diet and disease, it is essential to evaluate the performance of the dietary touchscreen questionnaire. The objectives of the present paper are to: describe the repeatability of the touchscreen questionnaire in participants (n 20 348) who repeated the assessment centre visit approximately 4 years after recruitment, and compare the dietary touchscreen variables with mean intakes from participants (n 140 080) who completed at least one of the four web-based 24-h dietary assessments post-recruitment. For fish and meat items, 90 % or more of participants reported the same or adjacent category of intake at the repeat assessment visit; for vegetables and fruit, and for a derived partial fibre score (in fifths), 70 % or more of participants were classified into the same or adjacent category of intake (κweighted > 0·50 for all). Participants were also categorised based on their responses to the dietary touchscreen questionnaire at recruitment, and within each category the group mean intake of the same food group or nutrient from participants who had completed at least one web-based 24-h dietary assessment was calculated. The comparison showed that the dietary touchscreen variables, available on the full cohort, reliably rank participants according to intakes of the main food groups.

Age at Menarche and Incidence of Diabetes: A Prospective Study of 300,000 Women in China

Previous studies of predominantly Western populations have reported inconsistent associations between age at menarche and risk of diabetes. We examined this relationship among Chinese women, who generally experience menarche at a later age than Western women. In 2004–2008, China Kadoorie Biobank recruited 302,632 women aged 30–79 years from 10 areas across China, and recorded 5,391 incident cases of diabetes during 7 years of follow-up among 270,345 women without baseline diabetes, cardiovascular disease or cancer. Cox regression models yielded adjusted hazard ratios for incident diabetes associated with age at menarche. Overall, the mean age at menarche was 15.4 years, and decreased across successive generations. Age at menarche was linearly and inversely associated with incident diabetes, with adjusted hazard ratio of 0.96 (95% confidence interval (CI): 0.94, 0.97) per year delay. Hazard ratios were greater in younger generations (for women born in the 1960s–1970s, hazard ratio (HR) = 0.93, 95% CI: 0.90, 0.97; for women born in the 1950s, HR = 0.95, 95% CI: 0.93, 0.98; and for women born in the 1920s–1940s, HR = 0.97, 95% CI: 0.95, 0.99). Further adjustment for adulthood body mass index significantly attenuated the association (HR = 0.99, 95% CI: 0.97, 1.00), especially among those born before 1950 (HR = 1.00, 95% CI: 0.97, 1.02). Much of the inverse association between age at menarche and incident diabetes was mediated through increased adiposity associated with early menarche, especially in older generations.

Hypercholesterolaemia - practical information for non-specialists

Hypercholesterolaemia is amongst the most common conditions encountered in the medical profession. It remains one of the key modifiable cardiovascular risk factors and there have been recent advances in the risk stratification methods and treatment options available. In this review, we provide a background into hypercholesterolaemia for non-specialists and consider the merits of the different risk assessment tools available. We also provide detailed considerations as to: i) when to start treatment, ii) what targets to aim for and iii) the role of low density lipoprotein cholesterol.

Associations of pet ownership with biomarkers of ageing: population based cohort study

OBJECTIVE

To examine the prospective relation between animal companionship and biomarkers of ageing in older people.

DESIGN

Analyses of data from the English Longitudinal Study of Ageing, an ongoing, open, prospective cohort study initiated in 2002-03.

SETTING

Nationally representative study from England.

PARTICIPANTS

8785 adults (55% women) with a mean age of 67 years (SD 9) at pet ownership assessment in 2010-11 (wave 5).

MAIN OUTCOME MEASURE

Established biomarkers of ageing in the domains of physical, immunological, and psychological function, as assessed in 2012-13 (wave 6).

RESULTS

One third of study members reported pet ownership: 1619 (18%) owned a dog, 1077 (12%) a cat, and 274 (3%) another animal. After adjustment for a range of covariates, there was no evidence of a clear association of any type of pet ownership with walking speed, lung function, chair rise time, grip strength, leg raises, balance, three markers of systemic inflammation, memory, or depressive symptoms.

CONCLUSION

In this population of older adults, the companionship of creatures great and small seems to essentially confer no relation with standard ageing phenotypes.

The associations of stroke, transient ischemic attack, and/or stroke-related recurrent vascular events with Lipoprotein-associated phospholipase A2: A systematic review and meta-analysis

BACKGROUND

Studies on stroke and lipoprotein-associated phospholipase A2 (Lp-PLA2) have produced conflicting results.

OBJECTIVE

The aim of the study was to assess the associations of Lp-PLA2 levels (mass and activity) with recurrent vascular events in patients with transient ischemic attack (TIA) and/or first ischemic stroke and with stroke in the general population.

METHODS

The MEDLINE, Embase, the Cochrane Library, Web of Science, Science Direct, China National Knowledge Infrastructure, China Biology Medical Disc (CBMdisc), and WanFang were searched for prospective observational studies reported until January 2017. Eligible studies reported Lp-PLA2 levels and adjusted risk estimates of recurrent vascular events and/or stroke. Risk ratio (RR) with corresponding 95% confidence intervals (CIs) were used to express the pooled data in a random-effects model.

RESULTS

A total of 11 studies that comprised 20,284 participants (4,045 were TIA and/or first ischemic stroke patients and 16,239 were residents in general population) were identified, which reported either Lp-PLA2 mass levels (4 studies) or Lp-PLA2 activity levels (10 studies). The pooled RR of recurrent vascular events (467 cases) in TIA and/or first ischemic group was 2.24 (95% CI, 1.33-3.78), whereas the pooled RR of stroke (1604 cases) in the general population was 1.47 (95% CI, 1.10-1.97). The pooled RRs of Lp-PLA2 mass and activity levels with the risk of stroke in the general population were 1.69 (95% CI, 1.03-2.79) and 1.28 (95% CI, 0.88-1.85), respectively.

CONCLUSIONS

In patients with TIA and first ischemic stroke, elevated Lp-PLA2 activity levels were associated with recurrent vascular events. And in the general population elevated Lp-PLA2 levels were associated with the risk of stroke, although the association between Lp-PLA2 activity levels and the risk of stroke was less profound compared with the corresponding association of stroke risk with the Lp-PLA2 mass levels.

Association of Physical Activity With Risk of Major Cardiovascular Diseases in Chinese Men and Women

Importance

In China, the patterns and levels of physical activity differed from those in high-income countries. Substantial uncertainty remains about the relevance, both qualitatively and quantitatively, of domain-specific physical activity for cardiovascular disease (CVD) subtypes in Chinese adults.

Objective

To assess the shape and strength of the associations of total, occupational, and nonoccupational physical activity with CVD subtypes in Chinese men and women.

Design, Setting, and Participants

This population-based prospective cohort study in 10 (5 urban, 5 rural) areas across China included 487 334 adults who were aged 30 to 79 (mean 51) years with no prior CVD history when enrolled from June 2004 to July 2008.

Exposures

Self-reported total, occupational, and nonoccupational physical activity, quantified as metabolic equivalent of task hours per day (MET-h/d) based on the type, frequency, and duration of specific activities.

Main Outcomes and Measures

Major vascular events (n = 36 184) and their components, including major coronary events (n = 5082), ischemic stroke (n = 25 647), intracerebral hemorrhage (n = 5252), and CVD death (n = 8437). Cox regression yielded adjusted hazard ratios for each disease that was associated with physical activity.

Results

Of the 487 334 study participants, 287 527 (59%) were women and the mean (SD) age was 51 (10.5) years. The overall mean (SD) total physical activity was 21.5 (12.8) MET-h/d, mainly from occupational activity, especially among men (75% vs 50% in women). Total physical activity was inversely associated with the risk of major vascular events, with the adjusted hazard ratio that compared the top vs bottom quintiles of physical activity being 0.77 (95% CI, 0.74-0.80). Throughout the range of total physical activity studied, the association with CVD with each 4 MET-h/d higher usual total physical activity (approximately 1 hour of brisk walking per day) associated with a 6% (95% CI, 5%-7%) lower risk of major vascular events, and a 9%, 5%, 6%, and 12% lower risk of major coronary events, ischemic stroke, intracerebral hemorrhage, and CVD death, respectively. The strength of the associations was similar and independent of each other for occupational and nonoccupational physical activity. However, for occupational physical activity, the associations with CVD subtypes were greatly attenuated above 20 MET-h/d, especially for intracerebral hemorrhage. The associations of total physical activity with major vascular events were similar among men and women and across different levels of sedentary leisure time but were much weaker among individuals with high blood pressure.

Conclusions and Relevance

Among Chinese adults, higher occupational or nonoccupational physical activity was associated with significantly lower risks of major CVD.

Body Mass Index and Vascular Disease in Men Aged 65 Years and Over: HIMS (Health In Men Study)

BACKGROUND

Understanding the relationship between body mass index (BMI) and vascular disease at older age has become increasingly important in the many countries where both average age and BMI are rising.

METHODS AND RESULTS

In this prospective cohort study, 12 203 men (aged ≥65) were recruited in 1996-1999 from the general population in Perth, Australia. To limit reverse causality, analyses excluded those with past vascular disease and the first 4 years of follow-up. During a further 8 (SD3) years of follow-up, there were 1136 first-ever major vascular events (nonfatal myocardial infarction, nonfatal stroke, or death from any vascular cause). Cox regression (adjusted for age, education, and smoking) related BMI at recruitment to incidence of major vascular events. At ages 65 to 94, the lowest risk of major vascular events was at ≈ 22.5 to 25 kg/m². In the higher BMI range (≥25 kg/m²), 5 kg/m² higher BMI was associated with 33% higher risk of major vascular events (hazard ratio, 1.33 [95% confidence interval, 1.18-1.49]): 24% higher risk of ischemic heart disease (1.24 [1.06-1.46]); 34% higher risk of stroke (1.34 [1.11-1.63]); and 78% higher risk of other vascular death (1.78 [1.32-2.41]). In the lower BMI range, there were fewer events and no strong evidence of an association (hazard ratio per 5 kg/m² higher BMI, 0.82 [95% confidence interval, 0.61-1.12]).

CONCLUSIONS

In this population of older men, risk of major vascular events was lowest at ≈ 22.5 to 25 kg/m². Above this range, BMI was strongly related to incidence of major vascular events, with each 5 kg/m² higher BMI associated with ≈30% higher risk.

Emotional states and future risk of venous thromboembolism

Emotional states of depression and loneliness are reported to be associated with higher risk and optimism with lower risk of arterial cardiovascular disease (CVD) and death. The relation between emotional states and risk of venous thromboembolism (VTE) has not been explored previously. We aimed to investigate the associations between self-reported emotional states and risk of incident VTE in a population-based, prospective study. The frequency of feeling depressed, lonely and happy/optimistic were registered by self-administered questionnaires, along with major co-morbidities and lifestyle habits, in 25,964 subjects aged 25–96 years, enrolled in the Tromsø Study in 1994–1995. Incident VTE-events were registered from the date of inclusion until September 1, 2007. There were 440 incident VTE-events during a median of 12.4 years of follow-up. Subjects who often felt depressed had 1.6-fold (95% CI:1.02–2.50) higher risk of VTE compared to those not depressed in analyses adjusted for other risk factors (age, sex , body mass index, oes-trogens), lifestyle (smoking, alcohol consumption, educational level) and co-morbidities (diabetes, CVD, and cancer). Often feeling lonely was not associated with VTE. However, the incidence rate of VTE in subjects who concurrently felt often lonely and depressed was higher than for depression alone (age-and sex-adjusted incidence rate: 3.27 vs. 2.21). Oppositely, subjects who often felt happy/optimistic had 40% reduced risk of VTE (HR 0.60, 95% CI: 0.41–0.87). Our findings suggest that self-reported emotional states are associated with risk of VTE. Depressive feelings were associated with increased risk, while happiness/ optimism was associated with reduced risk of VTE.

Longitudinal fasting blood glucose patterns and arterial stiffness risk in a population without diabetes

OBJECTIVE

To identify long-term fasting blood glucose trajectories and to assess the association between the trajectories and the risk of arterial stiffness in individuals without diabetes.

METHODS

We enrolled 16,454 non-diabetic participants from Kailuan cohort. Fasting blood glucose concentrations were measured in 2006, 2008, and 2010 survey. Brachial-ankle pulse wave velocities were measured during 2011 to 2016. Multivariate regression model was used to estimate the difference of brachial-ankle pulse wave velocity levels and logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (95%CIs) of arterial stiffness risk, according to the fasting blood glucose trajectories.

RESULTS

We identified five distinct fasting blood glucose trajectories and each of the trajectories was labeled according to its range and change over 2006-2010 survey: elevated-stable pattern (5.0% of participants), elevated-decreasing pattern (6.6%), moderate-increasing pattern (10.9%), moderate-stable pattern (59.3%), and low-stable pattern (18.2%). After adjustment for potential confounders, individuals with elevated-stable pattern had a 42.6 cm/s (95%CI: 24.7 to 60.6 cm/s) higher brachial-ankle pulse wave velocity level and a 37% (OR 1.37, 95%CI: 1.14 to 1.66) higher arterial stiffness risk, and individuals with moderate-increasing pattern had a 19.6 cm/s (95%CI: 6.9 to 32.3 cm/s) higher brachial-ankle pulse wave velocity level and a 17% (OR 1.17, 95%CI: 1.03 to 1.33) higher arterial stiffness risk, related to individuals with moderate-stable pattern. We did not find significant associations of the elevated-decreasing or low-stable patterns with arterial stiffness. Consistently, the cumulative average, variability, and increased rate of fasting blood glucose during 2006-2010 survey were significantly associated with the arterial stiffness risk.

CONCLUSION

Discrete fasting blood glucose trajectories were associated with the arterial stiffness risk in non-diabetic individuals.

Lowering LDL cholesterol reduces cardiovascular risk independently of presence of inflammation

Markers of inflammation, including plasma C-reactive protein (CRP), are associated with an increased risk of cardiovascular disease, and it has been suggested that this association is causal. However, the relationship between inflammation and cardiovascular disease has not been extensively studied in patients with chronic kidney disease. To evaluate this, we used data from the Study of Heart and Renal Protection (SHARP) to assess associations between circulating CRP and LDL cholesterol levels and the risk of vascular and non-vascular outcomes. Major vascular events were defined as nonfatal myocardial infarction, cardiac death, stroke or arterial revascularization, with an expanded outcome of vascular events of any type. Higher baseline CRP was associated with an increased risk of major vascular events (hazard ratio per 3x increase 1.28; 95% confidence interval 1.19-1.38). Higher baseline LDL cholesterol was also associated with an increased risk of major vascular events (hazard ratio per 0.6 mmol/L higher LDL cholesterol; 1.14, 1.06-1.22). Higher baseline CRP was associated with an increased risk of a range of non-vascular events (1.16, 1.12-1.21), but there was a weak inverse association between baseline LDL cholesterol and non-vascular events (0.96, 0.92-0.99). The efficacy of lowering LDL cholesterol with simvastatin/ezetimibe on major vascular events, in the randomized comparison, was similar irrespective of CRP concentration at baseline. Thus, decisions to offer statin-based therapy to patients with chronic kidney disease should continue to be guided by their absolute risk of atherosclerotic events. Estimation of such risk may include plasma biomarkers of inflammation, but there is no evidence that the relative beneficial effects of reducing LDL cholesterol depends on plasma CRP concentration.

Physical activity and 22-year all-cause and coronary heart disease mortality

BACKGROUND

This study explores the effects of occupational (OPA) and leisure time physical activity (LTPA) on mortality relative to cardiorespiratory fitness and pre-existing coronary heart disease (CHD).

METHODS

Associations between OPA, measured as energy expenditure (kcal/day) and relative aerobic workload (%VO₂ max), LTPA, and 22-year mortality among 1891 Finnish men were assessed by Cox regression models stratified by CHD and adjusted for 19 confounders.

RESULTS

In fully adjusted models, each 10% of relative aerobic workload increased all-cause mortality by 13% and CHD mortality 28% (P < 0.01). Compared to healthy subjects, men with CHD experienced lower mortality risks due to OPA and higher risks due to LTPA. While LTPA had no effect among healthy men, in men with CHD each weekly hour of conditioning LTPA increased all-cause mortality risks by 10% and CHD mortality by14%.

CONCLUSION

OPA was positively associated with both all-cause and CHD mortality. LTPA was not protective. Among men with CHD, LTPA increased mortality risks.

Longitudinal Change in Fasting Blood Glucose and Myocardial Infarction Risk in a Population Without Diabetes

OBJECTIVE

To examine the change in fasting blood glucose (FBG) during repeated assessments over time and its potential impact on the risk of developing myocardial infarction (MI).

RESEARCH DESIGN AND METHODS

This prospective cohort study included 68,297 participants without diabetes (mean age 49 years) who were free of MI, stroke, and cancer prior to or in 2010 (baseline of the current analysis). FBG concentrations were measured in 2006, 2008, and 2010. The FBG trajectories during 2006-2010, the primary exposure of the current study, were identified by latent mixture modeling. Incident MI cases were confirmed via review of medical records by cardiologists.

RESULTS

We identified five discrete FBG trajectories according to FBG range and changing pattern over time: elevated-stable (n = 3,877), elevated-decreasing (n = 7,060), moderate-increasing (n = 10,298), moderate-stable (n = 40,352), and low-stable (n = 6,710). During 4 years of follow-up, we documented 283 incident MI cases. Relative to the moderate-stable pattern (FBG ranged from 4.9 to 5.1 mmol/L), adjusted hazard ratios (HRs) were 1.53 (95% CI 1.04, 2.26) for the elevated-stable pattern (FBG ranged from 6.1 to 6.3 mmol/L) and HR 0.61 (95% CI 0.38, 0.98) for the elevated-decreasing pattern (FBG decreased from 6.0 to 5.4 mmol/L), after adjustment for potential confounders such as age, sex, lifestyle factors, obesity, medical history, blood pressure, blood lipids, and C-reactive protein. Consistently, cumulative average and increasing rate of FBG during 2006-2010, but not a single baseline FBG, predicted future risk of MI.

CONCLUSIONS

We found that discrete FBG trajectories were significantly associated with subsequent risk of MI in individuals without diabetes. These observations suggest that long-term trajectories of FBG may be important for risk prediction of MI and possibly other macrovascular diseases.

Use of Repeated Blood Pressure and Cholesterol Measurements to Improve Cardiovascular Disease Risk Prediction: An Individual-Participant-Data Meta-Analysis

The added value of incorporating information from repeated blood pressure and cholesterol measurements to predict cardiovascular disease (CVD) risk has not been rigorously assessed. We used data on 191,445 adults from the Emerging Risk Factors Collaboration (38 cohorts from 17 countries with data encompassing 1962-2014) with more than 1 million measurements of systolic blood pressure, total cholesterol, and high-density lipoprotein cholesterol. Over a median 12 years of follow-up, 21,170 CVD events occurred. Risk prediction models using cumulative mean values of repeated measurements and summary measures from longitudinal modeling of the repeated measurements were compared with models using measurements from a single time point. Risk discrimination (C-index) and net reclassification were calculated, and changes in C-indices were meta-analyzed across studies. Compared with the single-time-point model, the cumulative means and longitudinal models increased the C-index by 0.0040 (95% confidence interval (CI): 0.0023, 0.0057) and 0.0023 (95% CI: 0.0005, 0.0042), respectively. Reclassification was also improved in both models; compared with the single-time-point model, overall net reclassification improvements were 0.0369 (95% CI: 0.0303, 0.0436) for the cumulative-means model and 0.0177 (95% CI: 0.0110, 0.0243) for the longitudinal model. In conclusion, incorporating repeated measurements of blood pressure and cholesterol into CVD risk prediction models slightly improves risk prediction.

Elevated blood pressure and risk of mitral regurgitation: A longitudinal cohort study of 5.5 million United Kingdom adults

BACKGROUND

Mitral regurgitation in people without prior cardiac disease is considered a degenerative disease with no established risk factors for its prevention. We aimed to test the hypothesis that elevated systolic blood pressure (SBP) across its usual spectrum is associated with higher risk of mitral regurgitation.

METHODS AND FINDINGS

We used linked electronic health records from the United Kingdom Clinical Practice Research Datalink (CPRD) from 1 January 1990 to 31 December 2015. CPRD covers approximately 7% of the current UK population and is broadly representative of the population by age, sex, and ethnicity. About 5.5 million UK patients with no known cardiovascular or valve disease at baseline were included in this cohort study. We investigated the relationship between blood pressure (BP) and risk of mitral regurgitation using Cox regression models. Our primary exposure variable was SBP and our primary outcome was incident reports of mitral regurgitation, which were identified from hospital discharge reports or primary care records. Of the 5,553,984 patients in the CPRD that met our inclusion criteria, during the 10-year follow-up period, 28,655 (0.52%) were diagnosed with mitral regurgitation and a further 1,262 (0.02%) were diagnosed with mitral stenosis. SBP was continuously related to the risk of mitral regurgitation with no evidence of a nadir down to 115 mmHg (p < 0.001). Each 20 mmHg increment in SBP was associated with a 26% higher risk of mitral regurgitation (hazard ratio [HR] 1.26; CI 1.23, 1.29). The observed association was partially mediated by diseases affecting the left ventricle during follow-up (myocardial infarction [MI], ischaemic heart disease [IHD], cardiomyopathy, and heart failure). However, the percentage of excess risk mediated (PERM) by these proximate causes of secondary mitral regurgitation was only 13% (CI 6.1%, 20%), and accounting for them had little effect on the long-term association between SBP and mitral regurgitation (mediator-adjusted HR 1.22; CI 1.20, 1.25; p < 0.001). Associations were similar for each 10 mmHg increment in diastolic blood pressure (DBP) (p < 0.001) or each 15 mmHg increment in pulse pressure (PP) (p < 0.001). By contrast, there was no association between SBP and risk of mitral stenosis (HR per 20 mmHg higher SBP 1.03; CI 0.93, 1.14; p = 0.58). These analyses are based on routinely collected data from health records which may be sensitive to measurement errors, and the observed associations may not be generalizable to less severe and subclinical cases of mitral regurgitation.

CONCLUSIONS

Long-term exposure to elevated BP across its whole spectrum is associated with an increased risk of primary and secondary mitral regurgitation. These findings suggest that BP control may be of importance in the prevention of mitral regurgitation.

Fresh fruit consumption and all-cause and cause-specific mortality: findings from the China Kadoorie Biobank

Background

Higher fruit consumption is associated with lower risk of cardiovascular disease (CVD). Substantial uncertainties remain, however, about the associations of fruit consumption with all-cause mortality and mortality from subtypes of CVD and major non-vascular diseases, especially in China.

Methods

In 2004-08, the nationwide China Kadoorie Biobank Study recruited > 0.5 million adults aged 30-79 years from 10 diverse localities in China. Fresh fruit consumption was estimated using an interviewer-administered electronic questionnaire, and mortality data were collected from death registries. Among the 462 342 participants who were free of major chronic diseases at baseline, 17 894 deaths were recorded during ∼ 7 years of follow-up. Cox regression yielded adjusted rate ratios (RRs) for all-cause and cause-specific mortality associated with fruit consumption.

Results

At baseline, 28% of participants reported consuming fruit ≥ 4 days/week (regular consumers) and 6% reported never/rarely consuming fruit (non-consumers). Compared with non-consumers, regular consumers had 27% [RR = 0.73, 95% confidence interval (CI) 0.70-0.76] lower all-cause mortality, 34% lower CVD mortality (n = 6166; RR = 0.66, 0.61-0.71), 17% lower cancer mortality (n = 6796; RR = 0.83, 0.78-0.89) and 42% lower mortality from chronic obstructive pulmonary disease (COPD) (n = 1119; RR = 0.58, 0.47-0.71). For each of the above, there was an approximately log-linear dose-response relationship with amount consumed. For mortality from site-specific cancers, fruit consumption was inversely associated with digestive tract cancer (n = 2265; RR = 0.72, 0.64-0.81), particularly oesophageal cancer (n = 801; RR = 0.65, 0.50-0.83), but not with cancer of lung or liver.

Conclusions

Among Chinese adults, higher fresh fruit consumption was associated with significantly lower mortality from several major vascular and non-vascular diseases. Given the current low population level of fruit consumption, substantial health benefits could be gained from increased fruit consumption in China.

The kynurenine:tryptophan ratio as a predictor of incident type 2 diabetes mellitus in individuals with coronary artery disease

AIMS/HYPOTHESIS

The tryptophan metabolite kynurenine has potent immune modulatory and vasoactive properties. Experimental data implicate kynurenine in obesity-related morbidities. Epidemiological studies are, however, sparse. We evaluated associations of the plasma and urine kynurenine:tryptophan ratio (KTR) to incident type 2 diabetes.

METHODS

We followed 2519 individuals with coronary artery disease (CAD; 73.1% men) without diabetes at baseline for a median of 7.6 years, during which 173 (6.9%) new incidences of type 2 diabetes were identified. Multivariate Cox regression analyses were applied to investigate the prospective relationships of plasma and urine KTR with new onset type 2 diabetes.

RESULTS

At inclusion, mean (SD) age was 61.3 (10.4) years, BMI was 25.9 (3.71) kg/m2 and median (interquartile range) HbA1c was 5.6% (5.0%-6.0%) (38 [31-42] mmol/mol). Plasma KTR was not significantly related to type 2 diabetes risk. By contrast, urine KTR showed a strong positive association. Comparing quartile 4 with quartile 1, the HRs (95% CIs) were 2.59 (1.56, 4.30) and 2.35 (1.39, 3.96) in the age- and sex-adjusted and multivariate models, respectively.

CONCLUSIONS/INTERPRETATION

Urine KTR is a strong predictor of incident type 2 diabetes in individuals with CAD. Potential clinical implications and possible pathogenic roles of renal kynurenine excretion in type 2 diabetes development should be further elucidated.