Reverse Causality in Cardiovascular Epidemiological Research: More Common Than Imagined?

Lifestyle in adulthood can modify the causal relationship between BMI and islet function: using Mendelian randomization analysis

BACKGROUND

Body mass index was intimately associated with islet function, which was affected by various confounding factors. Among all methods of statistical analysis, Mendelian randomization best ruled out bias to find the causal relationship. In the present study, we explored the relationship between 13 East Asian body mass index-related genes reported previously and islet function using the Mendelian randomization method.

METHODS

A total of 2892 participants residing in northern China were enrolled. Anthropological information, such as sex, age, drinking status, smoking status, weight, height and blood pressure, was recorded for all participants. Fasting glucose and insulin were detected, and the insulin sensitivity index was calculated. 13 single nucleotide polymorphismss in East Asian body mass index -related genes were analysed with the ABI7900HT system.

RESULTS

Five genetic locus mutations, CDKAL1, MAP2K5, BDNF, FTO and SEC16B, were found to be associated with body mass index and were used to estimate the genetic risk score. We found that the genetic risk score was negatively associated with the insulin sensitivity index. Even after adjusted of confounding factors, the relationship showed statistical significance. A subsequent interaction effect analysis suggested that the negative relationship between the genetic risk score and insulin sensitivity index no longer existed in the nondrinking population, and smokers had a stronger negative relationship than nonsmokers.

CONCLUSION

We found a negative causal relationship between body mass index-related genetic locus mutations and insulin resistance, which might be increased by acquired lifestyle factors, such as drinking and smoking status.

Enhancer promoter interactome and Mendelian randomization identify network of druggable vascular genes in coronary artery disease

Coronary artery disease (CAD) is a multifactorial disorder, which is partly heritable. Herein, we implemented a mapping of CAD-associated candidate genes by using genome-wide enhancer-promoter conformation (H3K27ac-HiChIP) and expression quantitative trait loci (eQTL). Enhancer-promoter anchor loops from human coronary artery smooth muscle cells (HCASMC) explained 22% of the heritability for CAD. 3D enhancer-promoter genome mapping of CAD-genes in HCASMC was enriched in vascular eQTL genes. By using colocalization and Mendelian randomization analyses, we identified 58 causal candidate vascular genes including some druggable targets (MAP3K11, CAMK1D, PDGFD, IPO9 and CETP). A network analysis of causal candidate genes was enriched in TGF beta and MAPK pathways. The pharmacologic inhibition of causal candidate gene MAP3K11 in vascular SMC reduced the expression of athero-relevant genes and lowered cell migration, a cardinal process in CAD. Genes connected to enhancers are enriched in vascular eQTL and druggable genes causally associated with CAD.

Genetic Predisposition to Diabetes and Abdominal Aortic Aneurysm: A Two Stage Mendelian Randomisation Study

OBJECTIVE

Observational studies demonstrate an inverse association between type II diabetes and abdominal aortic aneurysm (AAA) for reasons that are unclear. The aim of this study was to clarify the causal association between type II diabetes predisposition and AAA using Mendelian randomisation.

METHODS

Effect estimates for single nucleotide polymorphisms (SNPs) associated with diabetes were obtained from the DIAbetes Meta-ANalysis of Trans-Ethnic association studies (DIAMANTE) consortium to construct a genetic instrumental variable. Corresponding effect estimates for associations of these SNPs with AAA were obtained from the International Aneurysm Consortium comprising six separate AAA genomewide association studies (4 972 cases and 99 858 controls). Mendelian randomisation estimates were calculated using inverse variance, weighted median, and MR-Egger methods, and compared against recently published observational estimates.

RESULTS

A genetic risk score was constructed from 206 SNPs associated with diabetes. All three Mendelian randomisation models showed no effect of genetic liability to diabetes and risk of AAA (inverse variance: odds ratio 1.04 per unit higher log odds, 95% 0.98 - 1.11, p = .19; MR-Egger slope p = .33; weighted median p = .50). Results were similar after excluding the TCF7L2 locus (inverse variance p = .075). Findings from the Mendelian randomisation analysis differed from previous observational reports of an inverse association (pdif < .001).

CONCLUSION

Lifelong genetic predisposition to diabetes does not appear to protect against AAA. These findings differ from traditional epidemiological studies showing an inverse association between diabetes and AAA, for reasons that remain unclear.

Association of Daily Sitting Time and Leisure-Time Physical Activity With Survival Among US Cancer Survivors

IMPORTANCE

Sedentary behaviors, particularly prolonged sitting and lack of physical activity, may influence survival after cancer.

OBJECTIVE

To examine the independent and joint associations of daily sitting time and leisure-time physical activity with mortality outcomes among cancer survivors.

DESIGN, SETTING, AND PARTICIPANTS

A prospective cohort of a nationally representative sample of cancer survivors, age 40 years or older (n = 1535; weighted population, 14 002 666), from the US National Health and Nutrition Examination Survey from 2007 to 2014. Participants were linked to mortality data from their interview and physical examination date through December 31, 2015. Daily sitting time and leisure-time physical activity (LTPA) were self-reported using the Global Physical Activity Questionnaire. Data analyses were performed from January 1 to May 1, 2021.

MAIN OUTCOMES AND MEASURES

All-cause, cancer-specific, and noncancer mortality.

RESULTS

Among 1535 cancer survivors (mean [SE] age, 65.1 [0.4] years; 828 [60.1%] females; 945 [83.1%] non-Hispanic White individuals), 950 (56.8%) reported LTPA of 0 minutes per week (min/wk) during the previous week (inactive); 226 (15.6%) reported LTPA of less than 150 min/wk (insufficiently active); 359 (27.6%) reported LTPA of 150 min/wk or more (active); 553 (35.4%) reported sitting for 6 to 8 hours per day (h/d); and 328 (24.9%) reported sitting for more than 8 h/d. Of note, 574 (35.8%) cancer survivors reported no LTPA with concurrent sitting of more than 6 h/d. During the follow-up period of up to 9 years (median, 4.5 years; 6980 person-years), there were 293 deaths (cancer, 114; heart diseases, 41; other causes, 138). Multivariable models showed that being physically active was associated with lower risks of all-cause (hazard ratio [HR], 0.34; 95% CI, 0.20-0.60) and cancer-specific (HR, 0.32; 95% CI, 0.15-0.70) mortality compared with inactivity. Sitting more than 8 h/d was associated with higher risks of all-cause (HR, 1.81; 95% CI, 1.05-3.14) and cancer-specific (HR, 2.27; 95% CI, 1.08-4.79) mortality compared with those sitting less than 4 h/d. In the joint analyses, prolonged sitting was associated with an increased risk of death among cancer survivors who were not sufficiently active. Specifically, inactive and insufficiently active survivors reported sitting more than 8 h/d had the highest overall (HR, 5.38; 95% CI, 2.99-9.67) and cancer-specific (HR, 4.71; 95% CI, 1.60-13.9) mortality risks.

CONCLUSIONS AND RELEVANCE

In this cohort study of a nationally representative sample of US cancer survivors, the combination of prolonged sitting with lack of physical activity was highly prevalent and was associated with the highest risks of death from all causes and cancer.

Paternal adherence to healthy dietary patterns in relation to sperm parameters and outcomes of assisted reproductive technologies

OBJECTIVE

To investigate whether men's adherence to dietary patterns promoted for the prevention of cardiovascular disease is associated with semen parameters and couples' assisted reproductive technology (ART) outcomes.

DESIGN

Prospective cohort study.

SETTING

Fertility center at an academic medical center.

PATIENT(S)

A total of 245 men and their female partners who underwent 438 ART cycles between 2007 and 2020.

INTERVENTION(S)

Male pretreatment dietary intake was assessed with a 131-item food frequency questionnaire from which we calculated eight a priori defined scores: Trichopoulou Mediterranean, Alternate Mediterranean, Panagiotakos Mediterranean, Healthy Eating Index, Alternative Healthy Eating Index, American Heart Association, Dietary Approaches to Stop Hypertension, and Plant-based.

MAIN OUTCOME MEASURE(S)

The primary outcome was live births per treatment cycle. The secondary outcomes were fertilization, implantation, and clinical pregnancy and seminogram parameters.

RESULT(S)

There was an inverse association between greater adherence by men to the Panagiotakos Mediterranean diet and the American Heart Association dietary pattern and lower fertilization rate. However, there were no significant associations between men's adherence to any of the analyzed dietary patterns and the probabilities of implantation, clinical pregnancy, or live birth in multivariable-adjusted models. No significant differences in any of the semen parameters were found between participants of the lowest quartile and those of the highest quartile of the eight dietary patterns.

CONCLUSION(S)

These findings suggest that men's adherence to several a priori defined dietary scores with documented cardiovascular benefits is not related to major outcomes of infertility treatment with ART or semen quality.

Assessment of bidirectional relationships between 98 genera of the human gut microbiota and amyotrophic lateral sclerosis: a 2-sample Mendelian randomization study

BACKGROUND

Growing evidence suggests a mutual interaction between gut microbiome alterations and ALS pathogenesis. However, previous studies were susceptible to potential confounding factors and reverse causation bias, likely leading to inconsistent and biased results.

OBJECTIVES

To decipher the potentially mutual relationship between gut microbiota and ALS, we used a bidirectional two-sample MR approach to examine the associations between the gut microbiome and ALS.

RESULTS

Using the inverse variance-weighted method, OTU10032 unclassified Enterobacteriaceae species-level OTU and unclassified Acidaminococcaceae were associated with a higher risk of ALS (per relative abundance: OR, 1.04; 95% CI, 1.01-1.07; P = 0.011 and OR, 1.02; 95% CI, 1.01-1.04; P = 0.009, respectively). Importantly, Gamma-Glu-Phe was showed potential deleterious effects on the risk of ALS (genetically predicted per a 1-standard deviation increase in the level of Gamma-Glu-Phe: OR, 1.96; 95% CI, 1.50-2.55; P = 0.012). Sensitivity analysis of the two candidate genera and metabolites using the MR-Egger and weighted-median methods produced similar estimates, and no horizontal pleiotropy or outliers were observed. Intriguingly, genetically predicted ALS was associated with an increase in the relative abundance of OTU4607_Sutterella (per 1-unit higher log odds: β, 2.23; 95% CI, 1.27-3.18; P = 0.020) and Lactobacillales_ORDER (per 1-unit higher log odds: β, 0.51; 95% CI, 0.09-0.94; P = 0.019).

CONCLUSIONS

Our findings provide novel evidence supporting the bidirectional relationship between the gut microbiota and ALS. These results may contribute to designing microbiome- and microbiome-dependent metabolite interventions in future ALS clinical trials.

Changes in the Frequency of Moderate-to-Vigorous Physical Activity and Subsequent Risk of All-Cause and Cardiovascular Disease Mortality

We investigated the association of changes in the frequency of moderate-to-vigorous physical activity (MVPA) and the risks of all-cause and cardiovascular disease (CVD) mortality. This study used the nationally representative National Health Insurance Service-National Sample Cohort database. We included 286,402 individuals aged ≥20 years and estimated changes in the frequency of MVPA over a two-year period. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazard regression models. The HRs (95% CIs) for the risk of all-cause and CVD mortality for an increased frequency of MVPA from physical inactivity compared with continual physical inactivity were 0.82 and 0.68 (0.73–0.92 and 0.51–0.91) for 1–2, 0.72 and 0.48 (0.62–0.84 and 0.31–0.74) for 3–4, and 0.73 and 0.70 (0.63–0.85 and 0.50–0.98) for ≥5 sessions of MVPA/week. The HRs (95% CIs) for the risk of all-cause and CVD mortality were 1.28 and 1.58 (1.07–1.53 and 1.01–2.46), 1.25 and 2.17 (1.01–1.57 and 1.14–4.12), and 1.43 and 1.44 (1.15–1.77 and 0.84–2.47) for changes from 1–2, 3–4, and ≥5 sessions of MVPA/week to physical inactivity, respectively. This study showed the beneficial effect of increasing physical activity, particularly for those who were physically inactive at baseline, as well as the increased risk of all-cause and CVD mortality after adapting a physically inactive lifestyle regardless of their baseline physical activity status.

Causal Association Between Alcohol Consumption and Atrial Fibrillation: A Mendelian Randomization Study

Previous observational studies presented a positive association between alcohol and atrial fibrillation (AF). However, previous studies using genetic polymorphisms on the causal relationship between alcohol consumption and AF have reported conflicting results. This study evaluated the causality between alcohol consumption and AF using the aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism. In 8,964 cohort participants, genetic analysis and Mendelian randomization analysis using the ALDH2 genotypes showed a significant causal association between alcohol consumption and AF in men.

Background and Objectives

Previous observational studies presented a positive association between alcohol and atrial fibrillation (AF). However, previous studies using genetic polymorphisms on the causal relationship between alcohol consumption and AF have reported conflicting results. This study aimed to evaluate the causality between alcohol consumption and AF using the aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism, which is the genetic variant with the most potent effect on drinking behavior.

Methods

A total of 8,964 participants from the Dong-gu Study were included in the present study. The causal association between alcohol consumption and AF was evaluated through a Mendelian randomization (MR) analysis using the ALDH2 rs671 polymorphism as an instrumental variable.

Results

No significant relationship between alcohol consumption and AF was found in the observational analysis. However, the genetic analysis using the ALDH2 polymorphism showed a significant association in men. In the MR analysis, genetically predicted daily alcohol consumption was positively related to AF.

Conclusions

MR analysis revealed a significant association between the amount of alcohol consumption and AF, which suggests that the association may be causal.

Leisure-time physical activity and risk of incident cardiovascular disease in Chinese retired adults

The optimum amounts and types of leisure-time physical activity (LTPA) for cardiovascular disease (CVD) prevention among Chinese retired adults are unclear. The prospective study enrolled 26,584 participants (mean age [SD]: 63.3 [8.4]) without baseline disease from the Dongfeng-Tongji cohort in 2013. Cox-proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During a mean 5.0 (1.5) years of follow-up, 5704 incident CVD cases were documented. Compared with less than 7.5 metabolic equivalent of task-hours per week (MET-hours/week) of LTPA, participating LTPA for 22.5-37.5 MET-hours/week, which was equivalent to 3 to 5 times the world health organization (WHO) recommended minimum, was associated with a 18% (95% CI 9 to 25%) lower CVD risk; however, no significant additional benefit was gained when exceeding 37.5 MET-hours/week. Each log10 increment of MET-hours/week in square dancing and cycling was associated with 11% (95% CI 2 to 20%) and 32% (95% CI 21 to 41%), respectively, lower risk of incident CVD. In Chinese retired adults, higher LTPA levels were associated with lower CVD risk, with a benefit threshold at 3 to 5 times the recommended physical activity minimum. Encouraging participation in square dancing and cycling might gain favourable cardiovascular benefits.

Musculoskeletal pain and sedentary behaviour in occupational and non-occupational settings: a systematic review with meta-analysis

BACKGROUND

Sedentary behaviour (SB; time spent sitting) is associated with musculoskeletal pain (MSP) conditions; however, no prior systematic review has examined these associations according to SB domains. We synthesised evidence on occupational and non-occupational SB and MSP conditions.

METHODS

Guided by a PRISMA protocol, eight databases (MEDLINE, CINAHL, PsycINFO, Web of Science, Scopus, Cochrane Library, SPORTDiscus, and AMED) and three grey literature sources (Google Scholar, WorldChat, and Trove) were searched (January 1, 2000, to March 17, 2021) for original quantitative studies of adults ≥ 18 years. Clinical-condition studies were excluded. Studies' risk of bias was assessed using the QualSyst checklist. For meta-analyses, random effect inverse-variance pooled effect size was estimated; otherwise, best-evidence synthesis was used for narrative review.

RESULTS

Of 178 potentially-eligible studies, 79 were included [24 general population; 55 occupational (incuding15 experimental/intervention)]; 56 studies were of high quality, with scores > 0.75. Data for 26 were meta-synthesised. For cross-sectional studies of non-occupational SB, meta-analysis showed full-day SB to be associated with low back pain [LBP - OR = 1.19(1.03 - 1.38)]. Narrative synthesis found full-day SB associations with knee pain, arthritis, and general MSP, but the evidence was insufficient on associations with neck/shoulder pain, hip pain, and upper extremities pain. Evidence of prospective associations of full-day SB with MSP conditions was insufficient. Also, there was insufficient evidence on both cross-sectional and prospective associations between leisure-time SB and MSP conditions. For occupational SB, cross-sectional studies meta-analysed indicated associations of self-reported workplace sitting with LBP [OR = 1.47(1.12 - 1.92)] and neck/shoulder pain [OR = 1.73(1.46 - 2.03)], but not with extremities pain [OR = 1.17(0.65 - 2.11)]. Best-evidence synthesis identified inconsistent findings on cross-sectional association and a probable negative prospective association of device-measured workplace sitting with LBP-intensity in tradespeople. There was cross-sectional evidence on the association of computer time with neck/shoulder pain, but insufficient evidence for LBP and general MSP. Experimental/intervention evidence indicated reduced LBP, neck/shoulder pain, and general MSP with reducing workplace sitting.

CONCLUSIONS

We found cross-sectional associations of occupational and non-occupational SB with MSP conditions, with occupational SB associations being occupation dependent, however, reverse causality bias cannot be ruled out. While prospective evidence was inconclusive, reducing workplace sitting was associated with reduced MSP conditions. Future studies should emphasise prospective analyses and examining potential interactions with chronic diseases.

PROTOCOL REGISTRATION

PROSPERO ID # CRD42020166412 (Amended to limit the scope).

Contributions of obesity to kidney health and disease: insights from Mendelian randomization and the human kidney transcriptomics

AIMS

Obesity and kidney diseases are common complex disorders with an increasing clinical and economic impact on healthcare around the globe. Our objective was to examine if modifiable anthropometric obesity indices show putatively causal association with kidney health and disease and highlight biological mechanisms of potential relevance to the association between obesity and the kidney.

METHODS AND RESULTS

We performed observational, one-sample, two-sample Mendelian randomization (MR) and multivariable MR studies in ∼300 000 participants of white-British ancestry from UK Biobank and participants of predominantly European ancestry from genome-wide association studies. The MR analyses revealed that increasing values of genetically predicted body mass index and waist circumference were causally associated with biochemical indices of renal function, kidney health index (a composite renal outcome derived from blood biochemistry, urine analysis, and International Classification of Disease-based kidney disease diagnoses), and both acute and chronic kidney diseases of different aetiologies including hypertensive renal disease and diabetic nephropathy. Approximately 13-16% and 21-26% of the potentially causal effect of obesity indices on kidney health were mediated by blood pressure and type 2 diabetes, respectively. A total of 61 pathways mapping primarily onto transcriptional/translational regulation, innate and adaptive immunity, and extracellular matrix and metabolism were associated with obesity measures in gene set enrichment analysis in up to 467 kidney transcriptomes.

CONCLUSIONS

Our data show that a putatively causal association of obesity with renal health is largely independent of blood pressure and type 2 diabetes and uncover the signatures of obesity on the transcriptome of human kidney.

Systolic Blood Pressure and Mortality in Community-Dwelling Older Adults: Frailty as an Effect Modifier

Current evidence is insufficient to support different hypertension treatment targets in older adults. We evaluated whether frailty modifies the association between systolic blood pressure (SBP) and 8-year all-cause mortality in community-dwelling older adults. Longitudinal data from the ActiFE Ulm study (Activity and Function in the Elderly in Ulm; Germany) was collected. The association between SBP and mortality was analyzed using Cox proportional hazards models adjusted for age, sex, education, smoking, alcohol consumption, sleep disturbance, diastolic blood pressure, and antihypertensive medications, evaluating the presence of effect modification by frailty according to a frailty index based on the accumulation of deficits. Among 1170 participants (median age 73.9 years, 41.6% women), the prevalence of history of hypertension was 53.8% (median SBP, 144.0 mm Hg [interquartile range, 135.0-149.5], median diastolic blood pressure 78.0 mm Hg [interquartile range, 71.0-86.5]). The median follow-up time was 8.1 years, detecting 268 deaths. We identified 251 (21.5%, 114 deaths) frail participants (frailty index ≥0.2). Effect modification by frailty was detected. Among non-frail a J-shaped association was found with hazard ratio, 4.01 (95% CI, 1.13-14.28) for SBP<110 mm Hg, hazard ratio, 0.92 (95% CI, 0.53-1.59) for SBP 140-150 mm Hg, and hazard ratio, 1.98 (95% CI, 0.75-5.27) for SBP≥160 mm Hg. For frail older adults, a tendency toward lower risk among those with SBP≥130 mm Hg was observed. Our results suggest the presence of effect modification by frailty indicating a possible protective effect for elevated SBP in frail older adults with respect to all-cause mortality even after adjusting for diastolic blood pressure and antihypertensive treatment.

Elevated Plasma Concentrations of Vitamin D-Binding Protein Are Associated with Lower High-Density Lipoprotein and Higher Fat Mass Index in Overweight and Obese Women

(1) Background: Observational studies have established that vitamin D-binding protein (DBP) and 25-hydroxyvitamin D₃ (25(OH)D) concentrations are the major factors affecting the bioavailability of 25(OH)D. It has also been shown that poor 25(OH)D bioavailability elevates the risk of obesity and its related cardio-metabolic disorders. However, the relationship between 25(OH)D and DBP concentrations with cardio-metabolic risk factors in overweight and obese cohorts has not been established. Consequently, we evaluated the association between DBP and 25(OH)D concentrations with lipid profile, blood pressure (BP), and body composition in overweight and obese women. (2) Methods: In this cross-sectional study of 236 overweight and obese women, DBP and 25(OH)D concentrations were measured using an enzyme-linked immunosorbent assay. Body composition was assessed via bioelectrical impedance analysis. Lipid profile and BP were assessed by an auto-analyzer and digital BP monitor, respectively. The associations were examined by multivariate logistic regression. (3) Results: The indicated showed an inverse relationship between DBP and high-density lipoprotein (HDL) (p = 0.010) concentrations (where individuals with higher DBP had lower HDL) which, after adjusting for possible cofounders, remained significant (p = 0.006). Moreover, DBP concentration was positively associated with fat mass index (FMI) after adjustment (p = 0.022). No significant relationships were observed among 25(OH)D and target variables. (4) Conclusions: In conclusion, lower concentrations of HDL and higher values of FMI are associated with higher concentrations of DBP in overweight and obese women. These findings present novel awareness regarding the association of DBP with some metabolic and body composition variables in overweight and obese women. However, a two-way causal relationship between DBP and target variables should be considered.

Exploring the interactions between Helicobacter pylori (Hp) infection and other risk factors of gastric cancer: A pooled analysis in the Stomach cancer Pooling (StoP) Project

Helicobacter pylori (Hp) is crucial in gastric carcinogenesis, but infection alone is not a sufficient cause, and the interaction between Hp infection and other risk factors has not been adequately studied. We conducted a pooled analysis of seven case-control studies from the Stomach cancer Pooling (StoP) Project, comprising 1377 cases and 2470 controls, to explore the interaction among Hp infection and tobacco smoking, alcohol drinking, socioeconomic status (SES) and dietary salt intake on the risk of gastric cancer. We estimated summary odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) by multivariate unconditional logistic regression. The analysis showed no consistent interaction between Hp infection and cigarette smoking, while interaction was more than multiplicative for alcohol drinking (OR = 1.38, 95% CI: 1.07-1.77, P-interaction 0.02) and high intake of salt (OR = 2.62, 95% CI: 1.88-3.65, P-interaction = 0.04). The interaction with SES followed the multiplicative model (P = 0.49), resulting in a weakening among infected individuals of the protective effect of high SES among observed Hp-negative individuals. The interactions found were more pronounced in subjects with history of peptic ulcer. The interactions with Hp infection were stronger for cigarette smoking and dietary salt in the case of noncardia cancer, and for alcohol and SES in the case of cardia cancer. No differences were found when stratifying for histologic type. This large-scale study aimed to quantify the interaction between Hp infection and other modifiable risk factors of gastric cancer revealed that the benefit of combined Hp eradication and lifestyle modification on gastric cancer prevention may be larger than commonly appreciated.

Sleep Quality and Perinatal Depression in Pregnant Women Treated in a Primary Care Centre in Lima, Peru

OBJECTIVE

The aim is to evaluate the association between sleep quality and perinatal depression in pregnant women between the 12th week of gestation and the 36th week of gestation in a maternity and child centre in Lima.

METHODS

Analytical cross-sectional study in pregnant women cared for in a primary care centre between August and December 2019. The data were collected through a self-administered survey. The Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. The evaluation of perinatal depression was performed with the Edinburgh Postnatal Depression Scale (EPDS). For the multivariate analysis, Poisson regression with robust variances was used to calculate the crude and adjusted prevalence ratios and their respective confidence intervals.

RESULTS

The sample was composed of 200 participants. The median [IQR] age was 26 [22-32] years, and 111 (55.5%) pregnancies were unplanned. 52% presented a poor quality of sleep and the risk of perinatal depression was 31.5%. Poor quality of sleep was associated with a significantly higher frequency of perinatal depression (aPR=4.8 for those with poor quality of sleep warranting medical attention, and aPR=6.6 for those with poor quality of sleep warranting medical attention and treatment).

CONCLUSIONS

There is a possible association between poor sleep quality and perinatal depression in pregnant women between weeks 12 and 36 of gestation. Operational research should be promoted to assess whether interventions to improve sleep quality could have a positive impact on reducing perinatal depression.

DNA damage in circulating leukocytes measured with the comet assay may predict the risk of death

The comet assay or single cell gel electrophoresis, is the most common method used to measure strand breaks and a variety of other DNA lesions in human populations. To estimate the risk of overall mortality, mortality by cause, and cancer incidence associated to DNA damage, a cohort of 2,403 healthy individuals (25,978 person-years) screened in 16 laboratories using the comet assay between 1996 and 2016 was followed-up. Kaplan–Meier analysis indicated a worse overall survival in the medium and high tertile of DNA damage (p < 0.001). The effect of DNA damage on survival was modelled according to Cox proportional hazard regression model. The adjusted hazard ratio (HR) was 1.42 (1.06–1.90) for overall mortality, and 1.94 (1.04–3.59) for diseases of the circulatory system in subjects with the highest tertile of DNA damage. The findings of this study provide epidemiological evidence encouraging the implementation of the comet assay in preventive strategies for non-communicable diseases.

Association of Dietary Patterns with Cardiovascular and Kidney Phenotypes in an Uruguayan Population Cohort

The impact of habitual diet on chronic diseases has not been extensively characterized in South America. We aimed to identify major dietary patterns (DP) in an adult cohort in Uruguay (Genotype Phenotype and Environment of Hypertension Study—GEFA-HT-UY) and to assess associations with metabolic, anthropometric characteristics, and cardiovascular and kidney phenotypes. In a cross-sectional study (n = 294), DP were derived by the principal component analysis. Blood and urine parameters, anthropometrics, blood pressure, pulse wave velocity, and glomerular filtration rate were measured. Multivariable adjusted linear models and adjusted binary logistic regression were used. Three DP were identified (Meat, Prudent, Cereal and Mate) explaining 22.6% of total variance in food intake. The traditional Meat DP, characterized by red and barbecued meat, processed meat, bread, and soft drinks, was associated with worse blood lipid profile. Prudent DP, characterized by vegetables, fish, and nuts, and lower loads for bread and crackers, was associated with reduced risk of vitamin D deficiency. Cereal and Mate DP, was characterized by higher loads of cereals, bread, and crackers, and mate infusion, with higher odds of excessive body weight. No direct associations of dietary patterns with hypertension, arterial stiffness, chronic kidney disease, and nephrolithiasis were found in the studied population, nor by age categories or sex.

Prognostic Value of Preoperative Absolute Lymphocyte Count in Children With Tetralogy of Fallot

Background

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Absolute lymphocyte count (ALC) is a low‐cost and easy‐to‐obtain inflammatory indicator; however, its association with the prognosis of patients with TOF remains unknown. This study aimed to determine the prognostic value of preoperative ALC in children with TOF.

Methods and Results

This retrospective study included 707 patients aged <6 years who underwent corrective operations for TOF between January 2016 and December 2018 in Fuwai Hospital, China. The end points were mortality, extracorporeal membrane oxygenation placement, postoperative hospital stay >30 days, and severe postoperative complications; patients were grouped on the basis of prognosis: poor prognosis (n=76) and good prognosis (n=631). Univariable and multivariable logistic regression analyses were performed to identify the independent risk factors for poor prognosis, on which a risk scoring system was based. The receiver operating characteristic curve was used to assess model performance. Using another model without ALC, the effect of the addition of ALC was assessed. Results suggested that ALC was an independent factor with a cutoff point of 4.36×10⁹/L. The addition of ALC improved the area under the curve from 0.771 to 0.781 (P<0.001). To avoid reverse causality and further control for confounding factors, the patients were further divided on the basis of ALC level, and a propensity score matching was performed; 117 paired patients were identified for further analysis. Low ALC levels had an odds ratio of 3.500 (95% CI, 1.413–8.672).

Conclusions

Low preoperative ALC represents an independent predictor of poor prognosis in children with TOF.

Exploration of Confounding Due to Poor Health in an Accelerometer-Mortality Study

PURPOSE

Confounding due to poor health is a concern in accelerometer-based studies of physical activity and health, but detailed investigations of this source of bias are lacking.

METHODS

US adults (n = 4840) from the National Health and Nutrition Examination Survey (2003 to 2006) wore an accelerometer for 1 to 7 d (mean = 5.7 d) and were followed for mortality through 2015. Logistic regression was used to examine odds ratios between poor health (chronic conditions, self-reported health, mobility limitations, frailty) and low physical activity levels; Cox models were used to estimate adjusted hazard ratios (HR) and 95% CI for mortality associations for a 1 h·d increase in moderate-to-vigorous-intensity physical activity (MVPA) using two commonly used cut-points (MVPA760, MVPA2020). Modeling scenarios with shorter and longer follow-up time, increasing adjustment for poor health, by age group, and after excluding early years of follow-up were used to assess bias.

RESULTS

Over a mean of 10.1 yr of follow-up, 1165 deaths occurred. Poor health was associated with low MVPA760 levels and increased mortality risk. In fully adjusted MVPA760 models, HR was 26% stronger comparing 0 to 4 yr (HR = 0.46) with 0 to 12 yr of follow-up (HR = 0.62), particularly in older adults (65 yr and older). Increasing statistical adjustment for poor health attenuated MVPA760 associations by 13% to 15%, and exclusion of the first 2 yr of follow-up had limited effects. Comparable results were obtained with the MVPA2020 cut-point.

CONCLUSIONS

We did not find evidence that confounding by health status resulted in entirely spurious MVPA-mortality associations; however, potential bias was appreciable in modeling scenarios involving shorter follow-up (<6 yr), older adults, and more limited statistical adjustment for poor health. The strength of MVPA-mortality associations in studies reflecting these scenarios should be interpreted cautiously.

White Blood Cells and Severe COVID-19: A Mendelian Randomization Study

Increasing evidence shows that white blood cells are associated with the risk of coronavirus disease 2019 (COVID-19), but the direction and causality of this association are not clear. To evaluate the causal associations between various white blood cell traits and the COVID-19 susceptibility and severity, we conducted two-sample bidirectional Mendelian Randomization (MR) analyses with summary statistics from the largest and most recent genome-wide association studies. Our MR results indicated causal protective effects of higher basophil count, basophil percentage of white blood cells, and myeloid white blood cell count on severe COVID-19, with odds ratios (OR) per standard deviation increment of 0.75 (95% CI: 0.60-0.95), 0.70 (95% CI: 0.54-0.92), and 0.85 (95% CI: 0.73-0.98), respectively. Neither COVID-19 severity nor susceptibility was associated with white blood cell traits in our reverse MR results. Genetically predicted high basophil count, basophil percentage of white blood cells, and myeloid white blood cell count are associated with a lower risk of developing severe COVID-19. Individuals with a lower genetic capacity for basophils are likely at risk, while enhancing the production of basophils may be an effective therapeutic strategy.

The role of cortisol in ischemic heart disease, ischemic stroke, type 2 diabetes, and cardiovascular disease risk factors: a bi-directional Mendelian randomization study

BACKGROUND

Cortisol, a steroid hormone frequently used as a biomarker of stress, is associated with cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM). To clarify whether cortisol causes these outcomes, we assessed the role of cortisol in ischemic heart disease (IHD), ischemic stroke, T2DM, and CVD risk factors using a bi-directional Mendelian randomization (MR) study.

METHODS

Single nucleotide polymorphisms (SNPs) strongly (P < 5 × 10-6) and independently (r2 < 0.001) predicting cortisol were obtained from the CORtisol NETwork (CORNET) consortium (n = 12,597) and two metabolomics genome-wide association studies (GWAS) (n = 7824 and n = 2049). They were applied to GWAS of the primary outcomes (IHD, ischemic stroke and T2DM) and secondary outcomes (adiposity, glycemic traits, blood pressure and lipids) to obtain estimates using inverse variance weighting, with weighted median, MR-Egger, and MR-PRESSO as sensitivity analyses. Conversely, SNPs predicting IHD, ischemic stroke, and T2DM were applied to the cortisol GWAS.

RESULTS

Genetically predicted cortisol (based on 6 SNPs from CORNET; F-statistic = 28.3) was not associated with IHD (odds ratio (OR) 0.98 per 1 unit increase in log-transformed cortisol, 95% confidence interval (CI) 0.93-1.03), ischemic stroke (0.99, 95% CI 0.91-1.08), T2DM (1.00, 95% CI 0.96-1.04), or CVD risk factors. Genetically predicted IHD, ischemic stroke, and T2DM were not associated with cortisol.

CONCLUSIONS

Contrary to observational studies, genetically predicted cortisol was unrelated to IHD, ischemic stroke, T2DM, or CVD risk factors, or vice versa. Our MR results find no evidence that cortisol plays a role in cardiovascular risk, casting doubts on the cortisol-related pathway, although replication is warranted.

Association Between Early Contact With Mental Health Services After an Offense and Reoffending in Individuals Diagnosed With Psychosis

IMPORTANCE

Psychosis is a known risk factor for offending behavior, but little is known about the association between clinical contact with mental health services after an offense and reoffending.

OBJECTIVE

To examine the association between early contact with mental health services and reoffending after an index offense in individuals with psychosis.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study, individuals diagnosed with psychosis before their index offense from July 1, 2001, to December 31, 2012, and who received a noncustodial sentence were identified by linking health and offending databases in New South Wales, Australia. The incidence of and risk factors for reoffending and time to reoffending within 2 years from the index offense were examined using Cox proportional hazards regression and Kaplan-Meier survival estimates. Specifically, the association between contact with mental health services within 30 days after an offense and reoffending was examined. Data were analyzed from July 1, 2019, to March 5, 2020.

EXPOSURES

Hospital admission, emergency department presentation, and contact with community mental health services associated with psychosis.

MAIN OUTCOMES AND MEASURES

Reoffending within 2 years of the index offense was compared in individuals with and without clinical contact with mental health services within 30 days after an offense, with adjustment for potential confounders.

RESULTS

Of the 7030 offenders with psychosis (4933 male [70.2%]; median age at the index offense, 34 [interquartile range, 26-42] years), 2605 (37.1%) had clinical contact with mental health services within 30 days after the index offense. The risk of reoffending was significantly lower in those with vs without clinical contact (adjusted hazard ratio [AHR], 0.83; 95% CI, 0.76-0.91). The risk of reoffending was 30% less in male offenders with 5 or more clinical contacts compared with male offenders with no clinical contact (AHR, 0.71; 95% CI, 0.59-0.84). Reoffending in both male and female offenders was associated with younger age (eg, AHR for male offenders aged <18 years, 3.31 [95% CI, 2.39-4.59]; AHR for female offenders aged <18 years, 2.60 [95% CI, 1.69-3.99]) and offending history (eg, AHR for male offenders with ≥4 prior offenses, 2.28 [95% CI, 1.98-2.64]; AHR for female offenders with ≥4 prior offenses, 2.22 [95% CI, 1.67-2.96]).

CONCLUSIONS AND RELEVANCE

In this cohort, early and frequent clinical contact with mental health services after an offense in individuals with psychosis was associated with reduced risk of reoffending in this group. More support may be needed for early treatment of those with serious mental illness who are at risk of reoffending.

Association between dietary patterns and renal function in a cross-sectional study using baseline data from the ELSA-Brasil cohort

Previous analyses of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) identified four main dietary patterns (DP). The aim of this study was to explore the association between the previously defined DP and renal function (RF). A cross-sectional study using the ELSA-Brasil baseline data was carried out. DP (“traditional”, “fruits and vegetables”, “bakery”, and “low sugar/low fat), metabolic syndrome (MS) using the Joint Interim Statement criteria, microalbuminuria (MA), and glomerular filtration rate (eGFR) through the CKD-EPI equation were evaluated. Abnormal RF was defined as eGFR<60 mL·min^-1·(1.73 m²)^-1 and MA≥3.0 mg/dL. Factors associated with RF were determined and mediation analysis was performed to investigate the association between DP, MS, and RF. A total of 15,105 participants were recruited, with a mean age of 52±9 years; 8,134 participants (54%) were females. The mediation analysis identified indirect associations between “bakery” and “fruits and vegetables”, and both were associated with decreased eGFR and albuminuria in both genders, compared with “traditional” and “low sugar/low fat” patterns in the general population. There was a direct association of the “bakery” pattern with MA in men (OR: 1.17, 95%CI: 1.92-1.48). The “fruits and vegetables” pattern also showed a direct association with reduced eGFR in women (OR: 1.65, 95%CI: 1.28-2.12), although there was no significance after adjustment. The “fruits and vegetables” and “bakery” DPs were associated with renal dysfunction. The only independent, direct association was between “bakery” DP and MA in men, raising concerns about DP and renal damage in men.

Community lessons to understand resuscitation excellence (culture): Association between emergency medical services (EMS) culture and outcome after out-of-hospital cardiac arrest

BACKGROUND

The large geographic variation in outcome after out-of-hospital cardiac arrest (OHCA) is not well explained by traditional patient and emergency medical services (EMS) characteristics. A 'culture of excellence' in resuscitation within an EMS is believed to be an important factor that influences quality of care and outcome in patients with OHCA. However, whether a culture of excellence is associated with improved survival after OHCA is not known.

METHODOLOGY

We linked survey responses from EMS agency medical directors related to resuscitation culture to a retrospective analysis of prospectively collected data from the Resuscitation Outcomes Consortium (ROC) Epistry - Cardiac Arrest. We used a multivariable random effects model to assess whether EMS culture strategies were associated with OHCA survival to hospital discharge.

RESULTS

Of the 46 EMS medical directors surveyed, 35 (76%) provided a complete response. Included were n = 66,597 cases of OHCA who received attempted resuscitation by one of n = 123 EMS agencies from July 1, 2010, through June 30, 2015. Overall survival to discharge was 11%. Organizational values and goals were independently associated with survival to hospital discharge in all OHCAs (adjusted odds ratio [AOR] 1.27, 95% confidence interval [CI] 1.09-1.48) and the subgroup restricted to bystander witnessed OHCAs with initial shockable rhythm (AOR 1.55, 95% CI 1.21-1.99).

CONCLUSIONS

An organizational goal to improve OHCA survival was independently associated with improved survival to discharge. EMS agencies looking to improve OHCA survival should consider implementing an organizational goal to improve OHCA survival and empower quality improvement personnel to drive that goal.

Cardiorespiratory Fitness Is Associated With Early Death Among Healthy Young and Middle-Aged Baby Boomers and Generation Xers

BACKGROUND

Increased mortality associated with low cardiorespiratory fitness has shown to take effect during late adulthood in previous generations. A recent rise in early death was observed in the United States. We investigated the impact of low cardiorespiratory fitness during young and middle adulthood on premature death in healthy adults from recent generations.

METHODS

A prospective cohort study of a nationally representative sample of US Baby Boomers and Generation Xers (born 1945-1980). Between 1999 and 2004, 3242 adults ages 20 to 49 years (weighted N = 59,888,450; mean age, 33.8 ± 0.2 years) underwent submaximal treadmill exercise test in the National Health and Nutrition Examination Survey study. Weighted Cox proportional hazards regression were used to evaluate the association of cardiorespiratory fitness with premature death at 65 years or younger.

RESULTS

During a mean follow-up of 13.8 years, 104 deaths (weighted deaths N =1,326,808) occurred. Low cardiorespiratory fitness was associated with an increased risk of premature death as a result of all-cause (hazard ratio [HR], low vs high: 2.26; 95% confidence interval [CI], 1.10 to 4.64, P for trend = 0.036) and cancer mortality (HR low vs moderate/high: 6.53; 95% CI, 2.38 to 17.9). Further, this association was stronger in adults ages 35 to 49 years at baseline (HR, 4.17 [95% CI, 1.19 to 9.11]).

CONCLUSION

We observed an inverse association between cardiorespiratory fitness during middle adulthood and premature death, which was not detected in preceding generations. These findings suggested that low cardiorespiratory fitness might be emerging as a new risk factor for early death among US Baby Boomers and Generation Xers.

Perspective: Current Pitfalls in the Search for Future Treatments and Prevention of Parkinson's Disease

We are gradually becoming aware that there is more to Parkinson's disease (PD) than meets the eye. Accumulating evidence has unveiled a disease complexity that has not (yet) been incorporated into ongoing efforts aimed at slowing, halting or reversing the course of PD, likely underlying their lack of success. There is a substantial latency between the actual onset of PD pathology and our ability to confirm diagnosis, during which accumulating structural and functional damage might be too advanced for effective modification or protection. Identification at the earliest stages of the disease course in the absence of Parkinsonism is crucial if we are to intervene when it matters most. Prognostic and therapeutic inferences can only be successful if we are able to accurately predict who is at risk for developing PD and if we can differentiate amongst the considerable clinicopathologic diversity. Biomarkers can greatly improve our identification and differentiation abilities if we are able to disentangle cause and effect.

External validation of the European risk assessment tool for chronic cardio-metabolic disorders in a Middle Eastern population

BACKGROUND

High burden of chronic cardio-metabolic disorders including type 2 diabetes mellitus (T2DM), chronic kidney disease (CKD), and cardiovascular disease (CVD) have been reported in the Middle East and North Africa region. We aimed to externally validate a non-laboratory risk assessment tool for the prediction of the chronic cardio-metabolic disorders in the Iranian population.

METHODS

The predictors included age, body mass index, waist circumference, use of antihypertensive medications, current smoking, and family history of cardiovascular disease and/or diabetes. For external validation of the model in the Tehran lipids and glucose study (TLGS), the Area under the curve (AUC) and the Hosmer-Lemeshow (HL) goodness of fit test were performed for discrimination and calibration, respectively.

RESULTS

Among 1310 men and 1960 women aged 28-85 years, 29.5% and 47.4% experienced chronic cardio-metabolic disorders during the 6 and 9-year follow-up, respectively. The model showed acceptable discrimination, with an AUC of 0.72 (95% CI 0.69-0.75) for men and 0.73 (95% CI 0.71-0.76) for women. The calibration of the model was good for both genders (min HL P = 0.5). Considering separate outcomes, AUC was highest for CKD (0.76 (95% CI 0.72-0.79)) and lowest for T2DM (0.65 (95% CI 0.61-0.69)), in men. As for women, AUC was highest for CVD (0.82 (95% CI 0.78-0.86)) and lowest for T2DM (0.69 (95% CI 0.66-0.73)). The 9-year follow-up demonstrated almost similar performances compared to the 6-year follow-up. Using Cox regression in place of logistic multivariable analysis, model's discrimination and calibration were reduced for prediction of chronic cardio-metabolic disorders; the issue which had more effect on the prediction of incident CKD among women. Moreover, adding data of educational levels and marital status did not improve, the discrimination and calibration in the enhanced model.

CONCLUSION

This model showed acceptable discrimination and good calibration for risk prediction of chronic cardio-metabolic disorders in short and long-term follow-up in the Iranian population.

Sodium and health-concordance and controversy

Nancy Cook and colleagues describe the sources of agreement and disagreement about the health effects of sodium and how they might be resolved

Dietary patterns and cardiovascular disease in Australian adults: Findings from the 2011-12 Australian Health Survey

BACKGROUND AND AIMS

Great discrepancies exist in results from studies examining the association between dietary patterns and cardiovascular disease (CVD) in different populations. The aim of this study is to examine the relationship between the Australian Dietary Guidelines (ADG) 2013, Mediterranean-DASH diet Intervention for Neurodegenerative Delay (MIND), Paleolithic and Okinawan dietary patterns and CVD respectively.

METHODS AND RESULTS

In this cross-sectional secondary analysis of the 2011-12 Australian Health Survey, adults who self-reported physician-diagnosed CVD, completed two multiple-pass 24 h recalls and had no missing data on all confounders were analysed (weighted n = 5376; 295 CVD cases). Dietary intake was transformed to represent usual intake by the multiple source method. The score of Healthy Eating Index for Australian Adults (HEIFA-2013) was adopted for ADG 2013, while the scores of MIND, Paleolithic and Okinawan dietary patterns were constructed by separating the intake of each predefined food and nutrient into quintiles. The associations between the dietary patterns (as tertiles of scores) and CVD were examined using binary logistic regression adjusted for significant cardiovascular risk factors. Higher adherence to the Okinawan diet pattern was significantly associated with a reduced prevalence of ischemic heart disease (IHD) (OR per unit increase in dietary pattern score: 0.94, 95%CI: 0.90-0.98). Comparing its extreme tertiles, the OR was 0.49 (95%CI: 0.29-0.82; p_trend < 0.01). The associations between HEIFA-2013, MIND and Paleolithic diet patterns and CVD were insignificant.

CONCLUSION

The findings suggested an inverse association between adherence to Okinawan dietary pattern and prevalence of IHD in Australian adults.

Usual physical activity and subsequent hospital usage over 20 years in a general population: the EPIC-Norfolk cohort

Background

While physical activity interventions have been reported to reduce hospital stays, it is not clear if, in the general population, usual physical activity patterns may be associated with subsequent hospital use independently of other lifestyle factors.

Objective

We examined the relationship between reported usual physical activity and subsequent admissions to hospital and time spent in hospital for 11,228 men and 13,786 women aged 40–79 years in the general population.

Methods

Participants from a British prospective population-based cohort study were followed for 20 years (1999–2019) using record linkage to document hospital usage. Total physical activity was estimated by combining workplace and leisure time activity reported in a baseline lifestyle questionnaire and repeated in a subset at a second time point approximately 12 years later.

Results

Compared to those reporting no physical activity, participants who were the most active had a lower likelihood of spending more than 20 days in hospital odds ratio (OR) 0.88 (95% confidence interval (CI) 0.81–0.96) over the next 20 years after multivariable adjustment for age, sex, smoking status, education, social class and body mass index. Participants reporting any activity had a mean of 0.42 fewer hospital days per year between 1999 and 2009 compared to inactive participants, an estimated potential saving to the National Health Service (NHS) of £247 per person per year, or approximately 7% of UK health expenditure. Participants who remained physically active or became active 12 years later had lower risk of subsequent hospital usage than those who remained inactive or became inactive, p-trend < 0.001.

Conclusion

Usual physical activity in this middle-aged and older population predicts lower future hospitalisations - time spent in hospital and number of admissions independently of behavioural and sociodemographic factors. Small feasible differences in usual physical activity in the general population may potentially have a substantial impact on hospital usage and costs.

Impact of follow-up time and analytical approaches to account for reverse causality on the association between physical activity and health outcomes in UK Biobank

BACKGROUND

The advent of very large cohort studies (n > 500 000) has given rise to prospective analyses of health outcomes being undertaken after short (<4 years) follow-up periods. However, these studies are potentially at risk of reverse causality bias. We investigated differences in the associations between self-reported physical activity and all-cause and cardiovascular disease (CVD) mortality, and incident CVD, using different follow-up time cut-offs and methods to account for reverse causality bias.

METHODS

Data were from n = 452 933 UK Biobank participants, aged 38-73 years at baseline. Median available follow-up time was 7 years (for all-cause and CVD mortality) and 6.1 years (for incident CVD). We additionally analysed associations at 1-, 2- and 4-year cut-offs after baseline. We fit up to four models: (1) adjusting for prevalent CVD and cancer, (2) excluding prevalent disease, (3) and (4) Model 2 excluding incident cases in the first 12 and 24 months, respectively.

RESULTS

The strength of associations decreased as follow-up time cut-off increased. For all-cause mortality, Model 1 hazard ratios were 0.73 (0.69-0.78) after 1 year and 0.86 (0.84-0.87) after 7 years. Associations were weaker with increasing control for possible reverse causality. After 7-years follow-up, the hazard ratios were 0.86 (0.84-0.87) and 0.88 (0.86-0.90) for Models 1 and 4, respectively. Associations with CVD outcomes followed similar trends.

CONCLUSIONS

As analyses with longer follow-up times and increased control for reverse causality showed weaker associations, there are implications for the decision about when to analyse a cohort study with ongoing data collection, the interpretation of study results and their contribution to meta-analyses.

Contrasting Associations of Body Mass Index and Hemoglobin A1c on the Excess Risk of Acute Myocardial Infarction and Heart Failure in Type 2 Diabetes Mellitus

Background Body mass index (BMI) may be a stronger risk factor for heart failure than for coronary heart disease in type 2 diabetes mellitus, but prior studies have not been powered to investigate the relative and absolute risks for acute myocardial infarction and heart failure in type 2 diabetes mellitus by BMI and glycemic level combined as compared with age- and sex-matched general population comparators. Methods and Results We identified 181 045 patients from The Swedish National Diabetes Registry, registered during 1998 to 2012 and 1538 434 general population comparators without diabetes mellitus, matched for age, sex, and county, all without prior major cardiovascular disease. Cases and comparators were followed with respect to the outcomes through linkage to the Swedish Inpatient Registry. Over a median follow-up time of 5.7 years, there were 28 855 acute myocardial infarction and 33 060 heart failure cases among patients and comparators. Excess risk (above that of comparators in whom no data on hemoglobin A1c and BMI was available), incidence rates and hazard ratios for heart failure were substantially higher among the obese patients compared with those with low BMI, where very obese patients (BMI ≥40 kg/m2) who also had poor glycemic control, suffered a 7-fold risk of heart failure versus comparators (reference level). By contrast, for acute myocardial infarction, the highest absolute and relative risks were found among patients with poor glycemic control, with no additional risk conferred by increasing BMI. Conclusions BMI is a strong independent risk factor for heart failure but not for acute myocardial infarction among patients with type 2 diabetes mellitus.

The impact of confounding on the associations of different adiposity measures with the incidence of cardiovascular disease: a cohort study of 296 535 adults of white European descent

Aims

The data regarding the associations of body mass index (BMI) with cardiovascular (CVD) risk, especially for those at the low categories of BMI, are conflicting. The aim of our study was to examine the associations of body composition (assessed by five different measures) with incident CVD outcomes in healthy individuals.

Methods and results

A total of 296 535 participants (57.8% women) of white European descent without CVD at baseline from the UK biobank were included. Exposures were five different measures of adiposity. Fatal and non-fatal CVD events were the primary outcome. Low BMI (≤18.5 kg m⁻²) was associated with higher incidence of CVD and the lowest CVD risk was exhibited at BMI of 22–23 kg m⁻² beyond, which the risk of CVD increased. This J-shaped association attenuated substantially in subgroup analyses, when we excluded participants with comorbidities. In contrast, the associations for the remaining adiposity measures were more linear; 1 SD increase in waist circumference was associated with a hazard ratio of 1.16 [95% confidence interval (CI) 1.13–1.19] for women and 1.10 (95% CI 1.08–1.13) for men with similar magnitude of associations for 1 SD increase in waist-to-hip ratio, waist-to-height ratio, and percentage body fat mass.

Conclusion

Increasing adiposity has a detrimental association with CVD health in middle-aged men and women. The association of BMI with CVD appears more susceptible to confounding due to pre-existing comorbidities when compared with other adiposity measures. Any public misconception of a potential ‘protective’ effect of fat on CVD risk should be challenged.

Take home figure

The Pharmacological Treatment of Arterial Hypertension in Frail, Older Patients—a Systematic Review

BACKGROUND

It is debated whether the treatment goals and decision-making algorithms for elderly patients with hypertension should be the same as those for younger patients. The American and European guidelines leave decisions about antihypertensive treatment in frail, institutionalized patients up to the treating physician. We therefore systematically searched the literature for publications on the phamacotherapy of arterial hypertension in frail patients.

METHODS

The MEDLINE, Embase, and Central databases were systematically searched for randomized, controlled trials (RCTs) and non-randomized studies, including observational studies, on the pharmacotherapy of arterial hypertension in elderly patients since the introduction of the concept of frailty, published over the period 1992-2017.

RESULTS

Out of 19 282 citations for randomized, controlled trials and 5659 for non-randomized trials and observational studies, four RCTs and three observational studies were included in the further analysis. The included RCTs showed a trend to- wards a benefit from pharmacotherapy of hypertension in frail patients with respect to mortality, cardiovascular disease, functional status, and quality of life. On the other hand, some of the observational studies indicated a lower rate of falls and lower mortality among patients who received no antihypertensive treatment.

CONCLUSION

In view of the conflicting findings of RCTs and non-randomized studies, the lower representation of frail subjects in RCTs, and the high risk of bias in non- randomized studies, the findings of the studies included in this review do not enable the formulation of any strictly evidence-based treatment recommendations. As a rule of thumb, the authors propose that a target systolic blood pressure of <150 mmHg should be aimed at in patients whose gait speed is less than 0.8 m/s, while a target range of 130-139 mmHg can be set for patients over age 80 who are no more than mildly frail.

Neighborhood walkability and 12-year changes in cardio-metabolic risk: the mediating role of physical activity

BACKGROUND

Living in walkable neighborhoods may provide long-term cardio-metabolic health benefits to residents. Little empirical research has examined the behavioral mechanisms in this relationship. In this longitudinal study, we examined the potential mediating role of physical activity (baseline and 12-year change) in the relationships of neighborhood walkability with 12-year changes in cardio-metabolic risk markers.

METHODS

The Australian Diabetes, Obesity and Lifestyle study collected data from adults, initially aged 25+ years, in 1999-2000, 2004-05, and 2011-12. We used 12-year follow-up data from 2023 participants who did not change their address during the study period. Outcomes were 12-year changes in waist circumference, weight, systolic and diastolic blood pressure, fasting and 2-h postload plasma glucose, high-density lipoprotein cholesterol, and triglycerides. A walkability index was calculated, using dwelling density, intersection density, and destination density, within 1 km street-network buffers around participants' homes. Spatial data for calculating these measures were sourced around the second follow-up period. Physical activity was assessed by self-reported time spent in moderate-to-vigorous physical activity (including walking). Multilevel models, adjusting for potential confounders, were used to examine the total and indirect relationships. The joint-significance test was used to assess mediation.

RESULTS

There was evidence for relationships of higher walkability with smaller increases in weight (P = 0.020), systolic blood pressure (P < 0.001), and high-density lipoprotein cholesterol (P = 0.002); and, for relationships of higher walkability with higher baseline physical activity (P = 0.020), which, in turn, related to smaller increases in waist circumference (P = 0.006), weight (P = 0.020), and a greater increase in high-density lipoprotein cholesterol (P = 0.005). There was no evidence for a relationship of a higher walkability with a change in physical activity during the study period (P = 0.590).

CONCLUSIONS

Our mediation analysis has shown that the protective effects of walkable neighborhoods against obesity risk may be in part attributable to higher baseline physical activity levels. However, there was no evidence of mediation by increases in physical activity during the study period. Further research is needed to understand other behavioral pathways between walkability and cardio-metabolic health, and to investigate any effects of changes in walkability.

The Effects of Reverse Causality and Selective Attrition on the Relationship Between Body Mass Index and Mortality in Postmenopausal Women

Concerns about reverse causality and selection bias complicate the interpretation of studies of body mass index (BMI, calculated as weight (kg)/height (m)2) and mortality in older adults. The objective of this study was to investigate methodological explanations for the apparent attenuation of obesity-related risks in older adults. We used data from 68,132 participants in the Women's Health Initiative (WHI) clinical trial for this analysis. All of the participants were postmenopausal women aged 50-79 years at baseline (1993-1998). To examine reverse causality and selective attrition, we compared rate ratios from inverse probability of treatment- and censoring-weighted Poisson marginal structural models with results from an unweighted adjusted Poisson regression model. The estimated mortality rate ratios and 95% confidence intervals for BMIs of 30.0-34.9, 35.0-39.9 and ≥40.0 were 0.86 (95% confidence interval (CI): 0.77, 0.96), 0.85 (95% CI: 0.72, 0.99), and 0.88 (95% CI: 0.72, 1.07), respectively, in the unweighted model. The corresponding mortality rate ratios were 0.96 (95% CI: 0.86, 1.07), 1.12 (95% CI: 0.97, 1.29), and 1.31 95% CI: (1.08, 1.57), respectively, in the marginal structural model. Results from the inverse probability of treatment- and censoring-weighted marginal structural model were attenuated in low BMI categories and increased in high BMI categories. The results demonstrate the importance of accounting for reverse causality and selective attrition in studies of older adults.

The Association Between Loneliness and Cognitive Impairment among Older Men and Women in China: A Nationwide Longitudinal Study

We aimed to investigate the association between loneliness and cognitive impairment among older men and women in China. Data for 6898 eligible participants aged 65 years and older were derived from the latest two waves (2008/2009 and 2011/2012) of the Chinese Longitudinal Healthy Longevity Survey. A logistic regression analysis was performed to determine whether the association between loneliness at baseline and the risk of cognitive impairment at follow-up varied by sex, with adjustment for social-demographic variables, social isolation, lifestyles, and health status. The rates of baseline loneliness and follow-up cognitive impairment were both higher among women than men. Loneliness at baseline was significantly associated with cognitive impairment at follow-up among elderly men (OR = 1.30; 95% CI 1.01-1.69), even after adjusting for potential confounding variables; however, a similar association was not observed among elderly women (OR = 0.98; 95% CI 0.81-1.19). Multiple imputations were applied to address missing data. Although elderly women more frequently reported feelings of loneliness, the impact of loneliness on cognitive impairment was significant among elderly men but not elderly women. Interventions designed to decrease the incidence of loneliness may be particularly beneficial for the reduction of cognitive impairment among elderly Chinese men.

BMI, Mortality, and Cardiovascular Outcomes in Type 1 Diabetes: Findings Against an Obesity Paradox

OBJECTIVE

Low weight has been associated with increased mortality risks in type 1 diabetes. We aimed to investigate the importance of weight and weight gain/loss in the Swedish population diagnosed with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Patients with type 1 diabetes (n = 26,125; mean age 33.3 years; 45% women) registered in the Swedish National Diabetes Registry from 1998 to 2012 were followed from the first day of study entry. Cox regression was used to calculate risk of death from cardiovascular disease (CVD), major CVD events, hospitalizations for heart failure (HF), and total deaths.

RESULTS

Population mean BMI in patients with type 1 diabetes increased from 24.7 to 25.7 kg/m² from 1998 to 2012. Over a median follow-up of 10.9 years, there were 1,031 deaths (33.2% from CVD), 1,460 major CVD events, and 580 hospitalizations for HF. After exclusion of smokers, patients with poor metabolic control, and patients with a short follow-up time, there was no increased risk for mortality in those with BMI <25 kg/m², while BMI >25 kg/m² was associated with a minor increase in risk of mortality, major CVD, and HF. In women, associations with BMI were largely absent. Weight gain implied an increased risk of mortality and HF, while weight loss was not associated with higher risk.

CONCLUSIONS

Risk of major CVD, HF, CVD death, and mortality increased with increasing BMI, with associations more apparent in men than in women. After exclusion of factors associated with reverse causality, there was no evidence of an obesity paradox.

Expanded normal weight obesity and blood pressure in Chinese adults: a community-based cross-sectional study

The study aimed to explore the independent association between expanded normal weight obesity categories and blood pressure among adults aged 20-80 years in China. By cross-sectional design, a total of 4279 adults living in Shaanxi Province, China, were selected from communities via multi-stage stratified cluster sampling in 2014. Information on anthropometric, body composition and blood pressure was collected and analysed. Expanded normal weight obesity (ENWO) categories were used to identify the level of bodyweight based on the combination of body mass index (BMI) and body fat percentage (BFP) categories. The age- and sex-standardised prevalence of hypertension increased within ENWO groups, from 10.12% in the underweight-low body fat group to 45.92% in the obesity-high body fat group. In under or normal weight participants, body fat percentage was found independently associated with hypertension in men, with an adjusted odds ratio of 3.69 in the fourth quartile of BFP compared with the first one. However, this effect was not observed in women. BFP was independently associated with increased risk of hypertension, especially in men. People with normal BMI should be re-identified as a high-risk population based on BFP level when it comes to hypertension prevention in primary healthcare settings.

Serum Magnesium is associated with Carotid Atherosclerosis in patients with high cardiovascular risk (CORDIOPREV Study)

This study aimed to ascertain whether there is an independent association between serum magnesium (Mg) and the Carotid Intima-Media Thickness (IMT-CC), a well-accepted atherosclerotic-biomarker surrogate of cardiovascular disease (CVD), in a population with high cardiovascular risk. Serum Mg and traditional atherosclerotic risk factors were recorded in 939 patients (mean age, 59.6 ± 0.3 years, 83.2% men) with coronary heart disease (CHD) enrolled in the CORDIOPREV trial. Serum Mg strongly associated with IMT-CC. Before adjusting for potential confounding factors, IMT-CC decreased by 0.111 ± 0.011 mm per mg/dl increase in serum Mg (p < 0.001). After adjustment, the effect of Mg did not appear mediated through factors related to glucose metabolism, the lipid profile or the mineral metabolism and renal function. Multivariate models showed the lower Mg levels (quartile 1) as a strong independent factor contributing to IMT-CC along with age, sex, SBP, HDL-C, and diuretic use. Logistic regression analysis confirmed the predictive ability of serum Mg to differentiate patients at higher atherosclerotic risk as defined by an IMT-CC ≥ 1.0 mm, yielding a OR for the lower quartile of 10.623 (95%CI 2.311–48.845; P = 0.002) and a ROC-derived cutoff of 1.61 mg/dl. Therefore, our findings outline low serum magnesium as a possible independent risk factor for carotid atherosclerosis.

Assessment of the Role of Carotid Atherosclerosis in the Association Between Major Cardiovascular Risk Factors and Ischemic Stroke Subtypes

IMPORTANCE

A better understanding of the role of atherosclerosis in the development of ischemic stroke subtypes could help to improve strategies for prevention of stroke worldwide.

OBJECTIVE

To assess the role of carotid atherosclerosis in the association between major cardiovascular risk factors and ischemic stroke subtypes.

DESIGN, SETTING, AND PARTICIPANTS

The prospective China Kadoorie Biobank cohort study was conducted in the general population of 5 urban and 5 rural areas in China, with a baseline survey obtained between June 2004 and July 2008. A random sample of 23 973 participants with no history of cardiovascular disease at enrollment who had carotid artery ultrasonographic measurements recorded at a resurvey from September 2013 to June 2014 were included. Data analysis was performed from July 1, 2016, to April 10, 2019.

EXPOSURES

Major cardiovascular risk factors (ie, blood pressure [BP], blood lipid levels, smoking, and diabetes).

MAIN OUTCOMES AND MEASURES

Carotid ultrasonographic measures of plaque burden (derived from number and maximum size of carotid artery plaques at resurvey) and first ischemic stroke during follow-up (n = 952), with subtyping (data release, August 2018) as lacunar (n = 263), probable large artery (n = 193), probable cardioembolic (n = 66), or unconfirmed (n = 430). Associations between cardiovascular risk factors, carotid plaque burden, and ischemic stroke subtypes were adjusted for age, sex, and geographic area.

RESULTS

The 23 973 participants in the study had a mean (SD) age of 50.6 (10.0) years, and 14 833 (61.9%) were women. Systolic BP had a stronger association (odds ratio [OR] per SD, 1.51; 95% CI, 1.42-1.61) than plaque burden (OR per SD, 1.34; 95% CI, 1.26-1.44) with ischemic stroke, and the associations of systolic BP with each subtype of ischemic stroke were modestly attenuated by adjustment for plaque burden. After adjustment for BP, plaque burden had a stronger association with probable large artery stroke (OR, 1.43; 95% CI, 1.24-1.63) than with lacunar stroke (OR, 1.25; 95% CI, 1.10-1.43) but was not associated with probable cardioembolic stroke (OR, 1.06; 95% CI, 0.83-1.36).

CONCLUSIONS AND RELEVANCE

Although BP was an important risk factor for all ischemic stroke subtypes, carotid atherosclerosis was an important risk factor only for large artery and lacunar strokes, suggesting that drug treatments targeting atherosclerosis may reduce the risk of stroke subtypes to different extents.

Body mass index and all-cause mortality in patients with atrial fibrillation: insights from the China atrial fibrillation registry study

BACKGROUND

Impact of body mass index (BMI) on all-cause mortality in atrial fibrillation (AF) patients remains controversial.

METHODS

A total of 10,942 AF patients were prospectively enrolled and categorized into four BMI groups: underweight (BMI < 18.5 kg/m²), normal weight (BMI 18.5-24 kg/m²), overweight (BMI 24-28 kg/m²) and obesity (BMI ≥ 28 kg/m²). The primary outcome was all-cause mortality. Different Cox proportional hazards models were performed to evaluate the association between BMI and all-cause mortality.

RESULTS

During a median follow-up of 30 months (IQR 18-48 months), 862 deaths events occurred. Compared to normal BMI, higher BMI was associated with a lower mortality risk (overweight: HR 0.70; 95% CI 0.61-0.81, P < 0.0001 and obesity: HR 0.54; 95% CI 0.44-0.67, P < 0.0001) and lower BMI was associated with a higher mortality risk (HR 2.23, 95% CI 1.67-2.97, P < 0.0001).

CONCLUSION

A reversed relationship between BMI and all-cause mortality in AF patients was found. Higher risk of mortality was observed in underweight patients compared to patients with a normal BMI, while overweight and obese patients had a lower risk of all-cause mortality.

CLINICAL TRIAL REGISTRATION

URL: http://www.chictr.org.cn/showproj.aspx?proj=5831. Unique identifier: ChiCTR-OCH-13003729.

Obesity and cardiovascular disease: revisiting an old relationship

A wealth of clinical and epidemiological evidence has linked obesity to a broad spectrum of cardiovascular diseases (CVD) including coronary heart disease, heart failure, hypertension, stroke, atrial fibrillation and sudden cardiac death. Obesity can increase CVD morbidity and mortality directly and indirectly. Direct effects are mediated by obesity-induced structural and functional adaptations of the cardiovascular system to accommodate excess body weight, as well as by adipokine effects on inflammation and vascular homeostasis. Indirect effects are mediated by co-existing CVD risk factors such as insulin resistance, hyperglycemia, hypertension and dyslipidemia. Adipose tissue (AT) quality and functionality are more relevant aspects for cardiometabolic risk than its total amount. The consequences of maladaptive AT expansion in obesity are local and systemic: the local include inflammation, hypoxia, dysregulated adipokine secretion and impaired mitochondrial function; the systemic comprise insulin resistance, abnormal glucose/lipid metabolism, hypertension, a pro-inflammatory and pro-thrombotic state and endothelial dysfunction, all of which provide linking mechanisms for the association between obesity and CVD. The present narrative review summarizes the major pathophysiological links between obesity and CVD (traditional and novel concepts), analyses the heterogeneity of obesity-related cardiometabolic consequences, and provides an overview of the cardiovascular impact of weight loss interventions.

"Mendelian Randomization" Approach in Economic Assessment of Health Conditions

The increased prevalence of non-communicable chronic diseases (NCDs) is reflected in the rising economic burden of health conditions. Observational studies conducted in health economics research are detecting associations of NCDs or related risk factors with economic measures like health insurance, economic inequalities, accessibility of jobs, education, annual income, health expenditure, etc. The inferences of such relationships do not prove causation and are limited to associations which are many times influenced by confounding factors and reverse causation. Mendelian randomization (MR) approach is a useful method for exploring causal relations between modifiable risk factors and measures of health economics. The application of MR in economic assessment of health conditions has been started and is producing fruitful results.

A Systemic Inflammatory Signature Reflecting Cross Talk Between Innate and Adaptive Immunity Is Associated With Incident Polyneuropathy: KORA F4/FF4 Study

Prospective analyses of biomarkers of inflammation and distal sensorimotor polyneuropathy (DSPN) are scarce and limited to innate immunity. We therefore aimed to assess associations between biomarkers reflecting multiple aspects of immune activation and DSPN. The study was based on 127 case subjects with incident DSPN and 386 noncase subjects from the population-based Cooperative Health Research in the Region of Augsburg (KORA) F4/FF4 cohort (follow-up 6.5 years). Proximity extension assay technology was used to measure serum levels of biomarkers of inflammation. Of 71 biomarkers assessed, 26 were associated with incident DSPN. After adjustment for multiple testing, higher levels of six biomarkers remained related to incident DSPN. Three of these proteins (MCP-3/CCL7, MIG/CXCL9, IP-10/CXCL10) were chemokines, and the other three (DNER, CD40, TNFRSF9) were soluble forms of transmembrane receptors. The chemokines had neurotoxic effects on neuroblastoma cells in vitro. Addition of all six biomarkers improved the C statistic of a clinical risk model from 0.748 to 0.783 (P = 0.011). Pathway analyses indicated that multiple cell types from innate and adaptive immunity are involved in the development of DSPN. We thus identified novel associations between biomarkers of inflammation and incident DSPN pointing to a complex cross talk between innate and adaptive immunity in the pathogenesis of the disease.

Home care workers in heart failure: a systematic review

Background

Home care workers (HCWs), which include home health aides and personal care aides, are increasingly used by heart failure (HF) patients for post-acute care and long-term assistance. Despite their growing presence, they have largely been left out of HF research and interventions. This systematic review was aimed to 1) describe utilization patterns of HCWs by adults with HF, 2) examine the effect of HCWs on HF outcomes, and 3) review HF interventions that involve HCWs.

Methods

Five electronic databases (Ovid MEDLINE, Ovid EMBASE, Cochrane Library [Wiley], CINAHL [EBSCO], and AgeLine [EBSCO]) were searched from inception through August 4, 2017. The yield was screened using prespecified inclusion and exclusion criteria. Two authors independently reviewed references and a third reviewer acted as an arbitrator when needed. Data were extracted from articles that met the inclusion criteria. The Downs and Black checklist was used for quality assessment. Due to study heterogeneity, a narrative synthesis was conducted.

Results

Of the 7,032 studies screened, 13 underwent full-text review, and six met the inclusion criteria. Two descriptive studies found that adults with HF who live alone and have functional and cognitive deficits utilize HCWs. While three retrospective cohort studies examined the association between having an HCW post-HF hospitalization and readmission rates, their findings were conflicting. One quasi-experimental study found that an HCW-delivered educational intervention improved HF patients’ self-care abilities. Overall, despite some significant findings, the studies assessed were of poor-to-fair quality (Downs and Black score range: 10–16 [28 total points]), with most lacking methodological rigor.

Conclusion

Although HCWs are quite common, the literature on these paraprofessionals in HF is limited. Given the paucity of research in this area and the low quality of studies reviewed here, additional research is warranted on the potential role of HCWs in HF self-care and on outcomes among adults with HF.

Causal Inference in Cancer Epidemiology: What Is the Role of Mendelian Randomization?

Observational epidemiologic studies are prone to confounding, measurement error, and reverse causation, undermining robust causal inference. Mendelian randomization (MR) uses genetic variants to proxy modifiable exposures to generate more reliable estimates of the causal effects of these exposures on diseases and their outcomes. MR has seen widespread adoption within cardio-metabolic epidemiology, but also holds much promise for identifying possible interventions for cancer prevention and treatment. However, some methodologic challenges in the implementation of MR are particularly pertinent when applying this method to cancer etiology and prognosis, including reverse causation arising from disease latency and selection bias in studies of cancer progression. These issues must be carefully considered to ensure appropriate design, analysis, and interpretation of such studies. In this review, we provide an overview of the key principles and assumptions of MR, focusing on applications of this method to the study of cancer etiology and prognosis. We summarize recent studies in the cancer literature that have adopted a MR framework to highlight strengths of this approach compared with conventional epidemiological studies. Finally, limitations of MR and recent methodologic developments to address them are discussed, along with the translational opportunities they present to inform public health and clinical interventions in cancer. Cancer Epidemiol Biomarkers Prev; 27(9); 995-1010. ©2018 AACR.