Sex Differences in Cardiovascular Disease Risk Factor Prevalence, Morbidity, and Mortality in Colombia: Findings from the Prospective Urban Rural Epidemiology (PURE) Study

Background

Controversies exist on whether the presence of cardiovascular risk factors and their association with major cardiovascular events (MACE) is different between men and women. Most of the evidence comes from high-income countries, hindering extrapolation of sociocultural and demographic factors of other regions.

Objective

To evaluate sex differences in the prevalence of cardiovascular risk factors and the incidence of MACE and diabetes in Colombian adults.

Methods

We performed a survival analysis from women and men aged 35-70 belonging to the Prospective Urban Rural Epidemiology-Colombia prospective study. Incidence rates for MACE composite (myocardial infarction, stroke, heart failure, death) and each outcome and diabetes were calculated. Kaplan-Meier curves and log-rank tests were performed. The association between demographic, behavioral, and metabolic variables with MACE and diabetes were evaluated with Cox proportional hazards models.

Results

7,552 participants (50±9.7 years) were included; 64% were women. Women had higher hypertension prevalence, body mass index, levels of total cholesterol, LDL-c, and HDL-c but lower triglycerides levels. Women were more sedentary but fewer smokers or active alcohol consumers and had higher educational levels. After 12-year mean follow-up (SD 2.3), the incidence rate of MACE composite was higher in men [4.2 (3.6-4.9) vs. 3.2 (2.8-3.7) cases per 1000 person-years]. Diabetes had the greatest association with MACE (HR = 2.63 95%CI:1.85;3.76), followed by hypertension (HR = 1.75 95%CI:1.30;2.35), low relative grip strength (HR = 1.53 95%CI:1.15;2.02), smoking (HR = 1.47 95%CI: 1.11;1.93), low physical activity (HR = 1.42 95%CI: 1.03;1.96). When evaluating risk factors by sex, only an increased waist-to-hip ratio was more strongly associated with MACE in men (p-interaction <0.05).

Conclusions

The composite MACE outcome was higher in men despite having a lower overall burden of risk factors. The risk factors contribution was similar, leading us to reconsider the need to carrying out differentiated cardiovascular risk prevention and management campaigns, at least in our region.

Stroke risk in women with atrial fibrillation

BACKGROUND AND AIMS

Female sex is associated with higher rates of stroke in atrial fibrillation (AF) after adjustment for other CHA2DS2-VASc factors. This study aimed to describe sex differences in age and cardiovascular care to examine their relationship with stroke hazard in AF.

METHODS

Population-based cohort study using administrative datasets of people aged ≥66 years diagnosed with AF in Ontario between 2007 and 2019. Cause-specific hazard regression was used to estimate the adjusted hazard ratio (HR) for stroke associated with female sex over a 2-year follow-up. Model 1 included CHA2DS2-VASc factors, with age modelled as 66-74 vs. ≥ 75 years. Model 2 treated age as a continuous variable and included an age-sex interaction term. Model 3 further accounted for multimorbidity and markers of cardiovascular care.

RESULTS

The cohort consisted of 354 254 individuals with AF (median age 78 years, 49.2% female). Females were more likely to be diagnosed in emergency departments and less likely to receive cardiologist assessments, statins, or LDL-C testing, with higher LDL-C levels among females than males. In Model 1, the adjusted HR for stroke associated with female sex was 1.27 (95% confidence interval 1.21-1.32). Model 2 revealed a significant age-sex interaction, such that female sex was only associated with increased stroke hazard at age >70 years. Adjusting for markers of cardiovascular care and multimorbidity further decreased the HR, so that female sex was not associated with increased stroke hazard at age ≤80 years.

CONCLUSION

Older age and inequities in cardiovascular care may partly explain higher stroke rates in females with AF.

PFTK1 kinase regulates axogenesis during development via RhoA activation

BACKGROUND

PFTK1/Eip63E is a member of the cyclin-dependent kinases (CDKs) family and plays an important role in normal cell cycle progression. Eip63E expresses primarily in postnatal and adult nervous system in Drosophila melanogaster but its role in CNS development remains unknown. We sought to understand the function of Eip63E in the CNS by studying the fly ventral nerve cord during development.

RESULTS

Our results demonstrate that Eip63E regulates axogenesis in neurons and its deficiency leads to neuronal defects. Functional interaction studies performed using the same system identify an interaction between Eip63E and the small GTPase Rho1. Furthermore, deficiency of Eip63E homolog in mice, PFTK1, in a newly generated PFTK1 knockout mice results in increased axonal outgrowth confirming that the developmental defects observed in the fly model are due to defects in axogenesis. Importantly, RhoA phosphorylation and activity are affected by PFTK1 in primary neuronal cultures. We report that GDP-bound inactive RhoA is a substrate of PFTK1 and PFTK1 phosphorylation is required for RhoA activity.

CONCLUSIONS

In conclusion, our work establishes an unreported neuronal role of PFTK1 in axon development mediated by phosphorylation and activation of GDP-bound RhoA. The results presented add to our understanding of the role of Cdks in the maintenance of RhoA-mediated axon growth and its impact on CNS development and axonal regeneration.

Adverse Childhood Experiences (ACEs) Predict Increased Arterial Stiffness from Childhood to Early Adulthood: Pilot Analysis of the Niagara Longitudinal Heart Study

An association among adults between adverse childhood experiences (ACEs) and arterial stiffness and between arterial stiffness and cardiovascular disease has been established. Recent cross-sectional evidence suggests that ACEs is linked to the development and progression of arterial stiffness, but it remains unclear when these changes begin to manifest. We examine the relationship between ACEs and changes in arterial stiffness from childhood into adulthood using population-based longitudinal data. The Niagara Longitudinal Heart Study (NLHS) pilot data included 76 young adults (females = 44), with an average age of 21 years (SD = 1), and had a follow-up period of 9 years. Mixed effects modeling was used to examine the effect of ACEs on changes in arterial stiffness over time adjusting for sex, changes in heart rate, systolic blood pressure, body mass index, and physical activity. Individuals with four or more ACEs have a greater increase in arterial stiffness over time from childhood into young adulthood. This increase was similar for both males and females and independent of the effects of change in heart rate, systolic blood pressure, body mass index, and physical activity. Exposure to ACEs is associated with greater increase in arterial stiffness, a marker for cardiovascular disease among adults. This suggests that interventions targeted at individuals with high exposure to ACEs early on in life could lower the risk of arterial stiffness and in turn the cascade of events leading to cardiovascular disease.

Body surface distribution of T wave alternans is modulated by heart rate and ventricular activation sequence in patients with cardiomyopathy

Background

T wave alternans (TWA) is an electrocardiographic marker of heightened sudden death risk from ventricular tachyarrhythmias in patients with cardiomyopathy. TWA is evaluated from the 12-lead electrocardiogram, Frank lead, or Holter lead recordings, however these clinical lead configurations will not record TWA from adjacent regions of the body torso.

Objective

We tested the hypothesis that changing heart rate or ventricular activation may alter the body surface distribution of TWA such that the clinical ECG leads fail to detect TWA in some patients; thereby producing a false-negative test.

Methods

In 28 cardiomyopathy patients (left ventricular ejection fraction 28±6%), 114 unipolar electrograms were recorded across the body torso during incremental atrial pacing, followed by atrioventricular pacing at 100, 110 and 120bpm. TWA was measured from each unipolar electrogram using the spectral method. A clinically positive TWA test was defined as TWA magnitude (V_alt) ≥1.9 uV with k ≥3 at ≤110bpm.

Results

Maximum V_alt (TWA_max) was greater from the body torso than clinical leads during atrial (p<0.005) and atrioventricular pacing (p<0.005). TWA_max was most prevalent in the right lower chest with atrial pacing 100 bpm and shifted to the left lower chest at 120 bpm. TWA_max was most prevalent in left lower chest with atrioventricular pacing at 100 bpm and shifted to the left upper chest at 120 bpm. Using the body torso as a gold standard, the false-negative rate for clinically positive TWA with clinical leads was 21% during atrial and 11% during atrioventricular pacing. Due to TWA signal migration outside the clinical leads, clinically positive TWA became false-negative when pacing mode was switched (atrial→atrioventricular pacing) in 21% of patients.

Conclusions

The body surface distribution of TWA is modulated by heart rate and the sequence of ventricular activation in patients with cardiomyopathy, which can give rise to modest false-negative TWA signal detection using standard clinical leads.

The duplication mutation of Quebec platelet disorder dysregulates PLAU, but not C10orf55, selectively increasing production of normal PLAU transcripts by megakaryocytes but not granulocytes

Quebec Platelet disorder (QPD) is a unique bleeding disorder that markedly increases urokinase plasminogen activator (uPA) in megakaryocytes and platelets but not in plasma or urine. The cause is tandem duplication of a 78 kb region of chromosome 10 containing PLAU (the uPA gene) and C10orf55, a gene of unknown function. QPD increases uPA in platelets and megakaryocytes >100 fold, far more than expected for a gene duplication. To investigate the tissue-specific effect that PLAU duplication has on gene expression and transcript structure in QPD, we tested if QPD leads to: 1) overexpression of normal or unique PLAU transcripts; 2) increased uPA in leukocytes; 3) altered levels of C10orf55 mRNA and/or protein in megakaryocytes and leukocytes; and 4) global changes in megakaryocyte gene expression. Primary cells and cultured megakaryocytes from donors were prepared for quantitative reverse polymerase chain reaction analyses, RNA-seq and protein expression analyses. Rapidly isolated blood leukocytes from QPD subjects showed only a 3.9 fold increase in PLAU transcript levels, in keeping with the normal to minimally increased uPA in affinity purified, QPD leukocytes. All subjects had more uPA in granulocytes than monocytes and minimal uPA in lymphocytes. QPD leukocytes expressed PLAU alleles in proportions consistent with an extra copy of PLAU on the disease chromosome, unlike QPD megakaryocytes. QPD PLAU transcripts were consistent with reference gene models, with a much higher proportion of reads originating from the disease chromosome in megakaryocytes than granulocytes. QPD and control megakaryocytes contained minimal reads for C10orf55, and C10orf55 protein was not increased in QPD megakaryocytes or platelets. Finally, our QPD megakaryocyte transcriptome analysis revealed a global down regulation of the interferon type 1 pathway. We suggest that the low endogenous levels of uPA in blood are actively regulated, and that the regulatory mechanisms are disrupted in QPD in a megakaryocyte-specific manner.

Genetics of Lipid and Lipoprotein Disorders and Traits

PURPOSE OF REVIEW

Plasma lipids, namely cholesterol and triglyceride, and lipoproteins, such as low-density lipoprotein (LDL) and high-density lipoprotein, serve numerous physiological roles. Perturbed levels of these traits underlie monogenic dyslipidemias, a diverse group of multisystem disorders. We are on the verge of having a relatively complete picture of the human dyslipidemias and their components.

RECENT FINDINGS

Recent advances in genetics of plasma lipids and lipoproteins include the following: (1) expanding the range of genes causing monogenic dyslipidemias, particularly elevated LDL cholesterol; (2) appreciating the role of polygenic effects in such traits as familial hypercholesterolemia and combined hyperlipidemia; (3) accumulating a list of common variants that determine plasma lipids and lipoproteins; (4) applying exome sequencing to identify collections of rare variants determining plasma lipids and lipoproteins that via Mendelian randomization have also implicated gene products such as NPC1L1, APOC3, LDLR, APOA5, and ANGPTL4 as causal for atherosclerotic cardiovascular disease; and (5) using naturally occurring genetic variation to identify new drug targets, including inhibitors of apolipoprotein (apo) C-III, apo(a), ANGPTL3, and ANGPTL4.

SUMMARY

Here, we compile this disparate range of data linking human genetic variation to plasma lipids and lipoproteins, providing a "one stop shop" for the interested reader.