Genome Wide Association Study Identifies the HMGCS2 Locus to be Associated With Chlorthalidone Induced Glucose Increase in Hypertensive Patients

Background

Thiazide and thiazide‐like diuretics are first‐line medications for treating uncomplicated hypertension. However, their use has been associated with adverse metabolic events, including hyperglycemia and incident diabetes mellitus, with incompletely understood mechanisms. Our goal was to identify genomic variants associated with thiazide‐like diuretic/chlorthalidone‐induced glucose change.

Methods and Results

Genome‐wide analysis of glucose change after treatment with chlorthalidone was performed by race among the white (n=175) and black (n=135) participants from the PEAR‐2 (Pharmacogenomic Evaluation of Antihypertensive Responses‐2). Single‐nucleotide polymorphisms with P<5×10⁻⁸ were further prioritized using in silico analysis based on their expression quantitative trait loci function. Among blacks, an intronic single‐nucleotide polymorphism (rs9943291) in the HMGCS2 was associated with increase in glucose levels following chlorthalidone treatment (ß=12.5; P=4.17×10⁻⁸). G‐allele carriers of HMGCS2 had higher glucose levels (glucose change=+16.29 mg/dL) post chlorthalidone treatment compared with noncarriers of G allele (glucose change=+2.80 mg/dL). This association was successfully replicated in an independent replication cohort of hydrochlorothiazide‐treated participants from the PEAR study (ß=5.54; P=0.023). A meta‐analysis of the 2 studies was performed by race in Meta‐Analysis Helper, where this single‐nucleotide polymorphism, rs9943291, was genome‐wide significant with a meta‐analysis P value of 3.71×10⁻⁸. HMGCS2, a part of the HMG‐CoA synthase family, is important for ketogenesis and cholesterol synthesis pathways that are essential in glucose homeostasis.

Conclusions

These results suggest that HMGCS2 is a promising candidate gene involved in chlorthalidone and Hydrochlorothiazide (HCTZ)‐induced glucose change. This may provide insights into the mechanisms involved in thiazide‐induced hyperglycemia that may ultimately facilitate personalized approaches to antihypertensive selection for hypertension treatment.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00246519 and NCT01203852.

Performance of individually measured vs population-based C-peptide kinetics to assess β-cell function in the presence and absence of acute insulin resistance

AIMS

To compare the performance of population-based kinetics with that of directly measured C-peptide kinetics when used to calculate β-cell responsivity indices, and to study people with and without acute insulin resistance to ensure that population-based kinetics apply to all conditions where β-cell function is measured.

METHODS

Somatostatin was used to inhibit endogenous insulin secretion in 56 people without diabetes. Subsequently, a C-peptide bolus was administered and the changing concentrations were used to calculate individual kinetic measures of C-peptide clearance. In addition, the participants were studied on 2 occasions in random order using an oral glucose tolerance test (OGTT). On one occasion, free fatty acid elevation, to cause insulin resistance, was achieved by infusion of Intralipid + heparin. The Disposition Index (DI) was then estimated by the oral minimal model using either population-based or individual C-peptide kinetics.

RESULTS

There were marked differences in the exchange variables (k ₁₂ and k ₂₁ ) of the model describing C-peptide kinetics, but smaller differences in the fractional clearance; that is, the irreversible loss from the accessible compartment (k ₀₁ ), obtained from population-based estimates compared with experimental measurement. Because it is predominantly influenced by k ₀₁ , DI estimated using individual kinetics correlated well with DI estimated using population-based kinetics.

CONCLUSIONS

These data support the use of population-based measures of C-peptide kinetics to estimate β-cell function during an OGTT.

Is Infection an Independent Risk Factor for Venous Thromboembolism? A Population-Based, Case-Control Study

BACKGROUND

The independent association of recent infection with venous thromboembolism is uncertain. The study aims were to test both overall infection (site unspecified) and specific infection sites as potential risk factors for deep vein thrombosis and pulmonary embolism adjusting for other known venous thromboembolism factors.

METHODS

By using Rochester Epidemiology Project resources, we identified all Olmsted County, Minnesota, residents with objectively diagnosed incident deep vein thrombosis or pulmonary embolism over the 13-year period 1988 to 2000 (cases; n = 1303) and 1 to 2 residents without venous thromboembolism matched to each case on age, sex, and incident venous thromboembolism date (controls; n = 1494). Using conditional logistic regression, we tested recent infection and infection site(s) for an association with venous thromboembolism, adjusting for body mass index, smoking, current/recent hospitalization with/without surgery, nursing home confinement, active cancer, trauma/fracture, leg paresis, prior superficial vein thrombosis, transvenous catheter/pacemaker, ischemic heart disease, congestive heart failure, chronic lung or renal disease, serious liver disease, asthma, diabetes mellitus, hormone therapy, and pregnancy/postpartum.

RESULTS

A total of 513 cases (39.4%) and 189 controls (12.7%) had an infection in the previous 92 days (odds ratio, 4.5; 95% confidence interval, 3.6-5.5; P < .0001). In a multivariable analysis adjusting for common venous thromboembolism risk factors, pneumonia and symptomatic urinary tract, oral, intra-abdominal, and systemic bloodstream infections were associated with significantly increased odds of venous thromboembolism.

CONCLUSIONS

Infection as a whole and specific infection sites in particular are independent risk factors for venous thromboembolism and should be considered as potential indications for venous thromboembolism prophylaxis.

Early Postmenopausal Transdermal 17β-Estradiol Therapy and Amyloid-β Deposition

Background: It remains controversial whether hormone therapy in recently postmenopausal women modifies the risk of Alzheimer’s disease (AD).

Objective: To investigate the effects of hormone therapy on amyloid-β deposition in recently postmenopausal women.

Methods: Participants within 5–36 months past menopause in the Kronos Early Estrogen Prevention Study, a randomized, double blinded placebo-controlled clinical trial, were randomized to: 1) 0.45 mg/day oral conjugated equine estrogens (CEE); 2) 50μg/day transdermal 17β-estradiol; or 3) placebo pills and patch for four years. Oral progesterone (200 mg/day) was given to active treatment groups for 12 days each month. ¹¹C Pittsburgh compound B (PiB) PET imaging was performed in 68 of the 118 participants at Mayo Clinic approximately seven years post randomization and three years after stopping randomized treatment. PiB Standard unit value ratio (SUVR) was calculated.

Results: Women (age = 52–65) randomized to transdermal 17β-estradiol (n = 21) had lower PiB SUVR compared to placebo (n = 30) after adjusting for age [odds ratio (95% CI) = 0.31(0.11–0.83)]. In the APOEɛ4 carriers, transdermal 17β-estradiol treated women (n = 10) had lower PiB SUVR compared to either placebo (n = 5) [odds ratio (95% CI) = 0.04(0.004–0.44)], or the oral CEE treated group (n = 3) [odds ratio (95% CI) = 0.01(0.0006–0.23)] after adjusting for age. Hormone therapy was not associated with PiB SUVR in the APOEɛ4 non-carriers.

Conclusion: In this pilot study, transdermal 17β-estradiol therapy in recently postmenopausal women was associated with a reduced amyloid-β deposition, particularly in APOEɛ4 carriers. This finding may have important implications for the prevention of AD in postmenopausal women, and needs to be confirmed in a larger sample.

A Human Study to Evaluate Safety, Tolerability, and Cyclic GMP Activating Properties of Cenderitide in Subjects With Stable Chronic Heart Failure

Cenderitide is a novel designer natriuretic peptide (NP) composed of C‐type natriuretic peptide (CNP) fused to the C‐terminus of Dendroaspis natriuretic peptide (DNP). Cenderitide was engineered to coactivate the two NP receptors, particulate guanylyl cyclase (pGC)‐A and ‐B. The rationale for its design was to achieve the renal‐enhancing and antifibrotic properties of dual receptor activation, but without clinically significant hypotension. Here we report the first clinical trial on the safety, tolerability, and cyclic guanosine monophosphate (cGMP) activating properties of Cenderitide in subjects with stable heart failure (HF). Four‐hour infusion of Cenderitide was safe, well‐tolerated, and significantly increased plasma cGMP levels and urinary cGMP excretion without adverse effects with no change in blood pressure. Thus, Cenderitide has a favorable safety profile and expected pharmacological effects in stable human HF. Our results support further investigations of Cenderitide in HF as a potential future cGMP‐enhancing therapeutic strategy.

Impaired Insulin Action Is Associated With Increased Glucagon Concentrations in Nondiabetic Humans

CONTEXT

Abnormal glucagon concentrations contribute to hyperglycemia, but the mechanisms of α-cell dysfunction in prediabetes are unclear.

OBJECTIVE

We sought to determine the relative contributions of insulin secretion and action to α-cell dysfunction in nondiabetic participants across the spectrum of glucose tolerance.

DESIGN

This was a cross-sectional study. A subset of participants (n = 120) was studied in the presence and absence of free fatty acid (FFA) elevation, achieved by infusion of Intralipid (Baxter Healthcare, Deerfield, IL) plus heparin, to cause insulin resistance.

SETTING

An inpatient clinical research unit at an academic medical center.

PARTICIPANTS

A total of 310 nondiabetic persons participated in this study.

INTERVENTIONS

Participants underwent a seven-sample oral glucose tolerance test. Subsequently, 120 participants were studied on two occasions. On one day, infusion of Intralipid plus heparin raised FFA. On the other day, participants received glycerol as a control.

MAIN OUTCOME MEASURE(S)

We examined the relationship of glucagon concentration with indices of insulin action after adjusting for the effects of age, sex, and weight. Subsequently, we sought to determine whether an acute decrease in insulin action, produced by FFA elevation, altered glucagon concentrations in nondiabetic participants.

RESULTS

Fasting glucagon concentrations correlated positively with fasting insulin and C-peptide concentrations and inversely with insulin action. Fasting glucagon was not associated with any index of β-cell function in response to an oral challenge. As expected, FFA elevation decreased insulin action and also raised glucagon concentrations.

CONCLUSIONS

In nondiabetic participants, glucagon secretion was altered by changes in insulin action.

Pregnancy history, coronary artery calcification and bone mineral density in menopausal women

OBJECTIVE

This study examined relationships, by pregnancy histories, between bone mineral density (BMD) and coronary artery calcification (CAC) in postmenopausal women.

METHODS

Forty women identified from their medical record as having pre-eclampsia (PE) were age/parity-matched with 40 women having a normotensive pregnancy (NP). Vertebral (T4-9) BMD and CAC were assessed by quantitative computed tomography in 73 (37 with PE and 36 with NP) of the 80 women. Analyses included linear regression using generalized estimating equations.

RESULTS

Women averaged 59 years of age and 35 years from the index pregnancy. There were no significant differences in cortical, trabecular or central BMD between groups. CAC was significantly greater in the PE group (p = 0.026). In multivariable analysis, CAC was positively associated with cortical BMD (p = 0.001) and negatively associated with central BMD (p = 0.036). There was a borderline difference in the association between CAC and central BMD by pregnancy history (interaction, p = 0.057).

CONCLUSIONS

Although CAC was greater in women with a history of PE, vertebral BMD did not differ between groups. However, both cortical and central BMD were associated with CAC. The central BMD association was marginally different by pregnancy history, suggesting perhaps differences in underlying mechanisms of soft tissue calcification.

Cerebrovascular Reactivity and Vascular Activation in Postmenopausal Women With Histories of Preeclampsia

Cerebrovascular reactivity (CVR) is reduced in patients with cognitive decline. Women with a history of preeclampsia are at increased risk for cognitive decline. This study examined an association between pregnancy history and CVR using a subgroup of 40 age- and parity-matched pairs of women having histories of preeclampsia (n=27) or normotensive pregnancy (n=29) and the association of activated blood elements with CVR. Middle cerebral artery velocity was measured by Doppler ultrasound before and during hypercapnia to assess CVR. Thirty-eight parameters of blood cellular elements, microvesicles, and cell-cell interactions measured in venous blood were assessed for association with CVR using principal component analysis. Middle cerebral artery velocity was lower in the preeclampsia compared with the normotensive group at baseline (63±4 versus 73±3 cm/s; P=0.047) and during hypercapnia (P=0.013-0.056). CVR was significantly lower in the preeclampsia compared with the normotensive group (2.1±1.3 versus 2.9±1.1 cm·s·mm Hg; P=0.009). Globally, the association of the 7 identified principal components with preeclampsia (P=0.107) and with baseline middle cerebral artery velocity (P=0.067) did not reach statistical significance. The interaction between pregnancy history and principal components with respect to CVR (P=0.084) was driven by a nominally significant interaction between preeclampsia and the individual principal component defined by blood elements, platelet aggregation, and interactions of platelets with monocytes and granulocytes (P=0.008). These results suggest that having a history of preeclampsia negatively affects the cerebral circulation years beyond the pregnancy and that this effect was associated with activated blood elements.

Systematic review for the 2017 AHA/ACC/HRS guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society

BACKGROUND

Although large randomized clinical trials have found that primary prevention use of an implantable cardioverter-defibrillator (ICD) improves survival in patients with cardiomyopathy and heart failure symptoms, patients who receive ICDs in practice are often older and have more comorbidities than patients who were enrolled in the clinical trials. In addition, there is a debate among clinicians on the usefulness of electrophysiological study for risk stratification of asymptomatic patients with Brugada syndrome.

AIM

Our analysis has 2 objectives. First, to evaluate whether ventricular arrhythmias (VAs) induced with programmed electrostimulation in asymptomatic patients with Brugada syndrome identify a higher risk group that may require additional testing or therapies. Second, to evaluate whether implantation of an ICD is associated with a clinical benefit in older patients and patients with comorbidities who would otherwise benefit on the basis of left ventricular ejection fraction and heart failure symptoms.

METHODS

Traditional statistical approaches were used to address 1) whether programmed ventricular stimulation identifies a higher-risk group in asymptomatic patients with Brugada syndrome and 2) whether ICD implantation for primary prevention is associated with improved outcomes in older patients (>75 years of age) and patients with significant comorbidities who would otherwise meet criteria for ICD implantation on the basis of symptoms or left ventricular function.

RESULTS

Evidence from 6 studies of 1138 asymptomatic patients were identified. Brugada syndrome with inducible VA on electrophysiological study was identified in 390 (34.3%) patients. To minimize patient overlap, the primary analysis used 5 of the 6 studies and found an odds ratio of 2.3 (95% CI: 0.63-8.66; p=0.2) for major arrhythmic events (sustained VAs, sudden cardiac death, or appropriate ICD therapy) in asymptomatic patients with Brugada syndrome and inducible VA on electrophysiological study versus those without inducible VA. Ten studies were reviewed that evaluated ICD use in older patients and 4 studies that evaluated unique patient populations were identified. In our analysis, ICD implantation was associated with improved survival (overall hazard ratio: 0.75; 95% confidence interval: 0.67-0.83; p<0.001). Ten studies were identified that evaluated ICD use in patients with various comorbidities including renal disease, chronic obstructive pulmonary disease, atrial fibrillation, heart disease, and others. A random effects model demonstrated that ICD use was associated with reduced all-cause mortality (overall hazard ratio: 0.72; 95% confidence interval: 0.65-0.79; p<0.0001), and a second "minimal overlap" analysis also found that ICD use was associated with reduced all-cause mortality (overall hazard ratio: 0.71; 95% confidence interval: 0.61-0.82; p<0.0001). In 5 studies that included data on renal dysfunction, ICD implantation was associated with reduced all-cause mortality (overall hazard ratio: 0.71; 95% confidence interval: 0.60-0.85; p<0.001).

Genetic Variants Associated With Uncontrolled Blood Pressure on Thiazide Diuretic/β-Blocker Combination Therapy in the PEAR (Pharmacogenomic Evaluation of Antihypertensive Responses) and INVEST (International Verapamil-SR Trandolapril Study) Trials

BACKGROUND

The majority of hypertensive individuals require combination antihypertensive therapy to achieve adequate blood pressure (BP) control. This study aimed to identify genetic variants associated with uncontrolled BP on combination therapy with a thiazide diuretic and a β-blocker.

METHODS AND RESULTS

A genome-wide association study of uncontrolled BP on combination therapy was conducted among 314 white participants of the PEAR (Pharmacogenomic Evaluation of Antihypertensive Responses) trial. Multivariable logistic regression analysis was used. Genetic variants meeting a suggestive level of significance (P<1.0E-05) were tested for replication in an external cohort, INVEST (International Verapamil-SR Trandolapril study). We also examined genome-wide variant associations with systolic and diastolic BP response on combination therapy and tested for replication. We discovered a single nucleotide polymorphism, the rs261316 major allele, at chromosome 15 in the gene ALDH1A2 associated with an increased odds of having uncontrolled BP on combination therapy (odds ratio: 2.56, 95% confidence interval, 1.69-3.88, P=8.64E-06). This single nucleotide polymorphism replicated (odds ratio: 1.86, 95% confidence interval, 1.35-2.57, P=0.001) and approached genome-wide significance in the meta-analysis between discovery and replication cohorts (odds ratio: 2.16, 95% confidence interval, 1.63-2.86, P=8.60E-08). Other genes in the region surrounding rs261316 (ALDH1A2) include AQP9 and LIPC.

CONCLUSIONS

A single nucleotide polymorphism in the gene ALDH1A2 may be associated with uncontrolled BP following treatment with a thiazide diuretic/β-blocker combination.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00246519.

Characterization of intravascular cellular activation in relationship to subclinical atherosclerosis in postmenopausal women

Objective

Mechanisms and interactions among intravascular cells contributing to development of subclinical atherosclerosis are poorly understood. In women, both menopausal status and pregnancy history influence progression of atherosclerosis. This study examined activation and interactions among blood elements with subclinical atherosclerosis in menopausal women with known pregnancy histories.

Methods

Carotid intima-media thickness (CIMT), as a marker of subclinical atherosclerosis, was measured using B-mode ultrasound in age- and parity-matched women [40 with and 40 without a history of preeclampsia] 35 years after the index pregnancy. Interactions among intravascular cells (38 parameters) were measured by flow cytometry in venous blood. Data analysis was by principal component which retained 7 independent dimensions accounting for 63% of the variability among 38 parameters.

Results

CIMT was significantly greater in women with a history of preeclampsia (P = 0.004). Platelet aggregation and platelet interactions with granulocytes and monocytes positively associated with CIMT in postmenopausal women independent of their pregnancy history (ρ = 0.258, P< 0.05). However, the association of the number of platelets, platelet activation and monocyte-platelet interactions with CIMT differed significantly depending upon pregnancy history (test for interaction, P<0.001).

Conclusion

Interactions among actived intravascular cells and their association with subclinical atherosclerosis differ in women depending upon their pregnancy histories.

Thrombin generation profiles as predictors of symptomatic venous thromboembolism after trauma: A prospective cohort study

BACKGROUND

Reliable biomarkers predictive of venous thromboembolism (VTE) after acute trauma are uncertain. The objective of the study was to identify risk factors for symptomatic VTE after trauma, including individual plasma coagulome characteristics as reflected by thrombin generation.

METHODS

In a prospective, case-cohort study, trauma patients were enrolled over the 4.5-year period, 2011 to 2015. Blood was collected by venipuncture into 3.2% trisodium citrate at 0, 6, 12, 24, and 72 hours after injury and at hospital discharge. Platelet poor plasma was stored at -80 °C until analysis. Thrombin generation, as determined by the calibrated automated thrombogram (CAT) using 5 pM tissue factor (TF)/4 μM phospholipid (PS), was reported as peak height (nM thrombin) and time to peak height (ttPeak [minutes]). Data are presented as median [IQR] or hazard ratio with 95% CI.

RESULTS

Among 453 trauma patients (injury severity score = 13.0 [6.0, 22.0], hospital length of stay = 4.0 [2.0, 10.0] days, age = 49 [28, 64] years, 71% male, 96% with blunt mechanism, mortality 3.2%), 83 developed symptomatic VTE within 92 days after injury (35 [42%] after hospital discharge). In a weighted, multivariate Cox model that included clinical and CAT characteristics available within 24 hours of admission, increased patient age (1.35 [1.19,1.52] per 10 years, p < 0.0001), body mass index ≥30 kg/m (4.45 [2.13,9.31], p < 0.0001), any surgery requiring general anesthesia (2.53 [1.53,4.19], p = 0.0003) and first available ttPeak (1.67 [1.29, 2.15], p < 0.00001) were independent predictors of incident symptomatic VTE within 92 days after trauma (C-statistic = 0.799).

CONCLUSION

The individual's plasma coagulome (as reflected by thrombin generation) is an independent predictor of VTE after trauma. Clinical characteristics and ttPeak can be used to stratify acute trauma patients into high and low risk for VTE.

LEVEL OF EVIDENCE

Prognostic, level III.

Carotid Artery Intima-Media Thickness and Subclinical Atherosclerosis in Women With Remote Histories of Preeclampsia: Results From a Rochester Epidemiology Project-Based Study and Meta-analysis

OBJECTIVE

To measure carotid artery intima-media thickness (CIMT), a marker of subclinical atherosclerosis, in postmenopausal women with and without histories of preeclampsia and to synthesize these results with those from prior studies of CIMT performed 10 or more years after preeclamptic pregnancies.

PATIENTS AND METHODS

Forty women (median age, 59 years) with histories of preeclampsia and 40 with histories of normotensive pregnancy (confirmed by medical record review) were selected from women who resided and gave birth in Olmsted County, Minnesota, between January 1, 1976, and December 31, 1982. The participants were identified and recruited in 2014-2015, and CIMT was measured by B-mode ultrasonography. Meta-analysis included CIMT studies that were performed 10 or more years after preeclamptic pregnancies and which were identified through PubMed, EMBASE, and Web of Science. Heterogeneity was assessed using the I² statistic. Standardized mean difference was used as a measure of effect size.

RESULTS

Carotid artery intima-media thickness, expressed as a median (interquartile range), was greater in the preeclamptic than in the normotensive group (0.80 mm [0.75-0.85 mm] vs 0.73 mm [0.70-0.78]; P=.004); the odds of having CIMT higher than threshold (0.77 mm) was statistically significant after adjusting for confounding factors (odds ratio, 3.17; 95% CI, 1.10-9.14). A meta-analysis of 10 studies conducted 10 or more years post partum included 813 women with and 2874 without histories of preeclampsia. Carotid artery intima-media thickness was greater among women with histories of preeclampsia, with a standardized mean difference of 0.18 and 95% CI of 0.05 to 0.30 mm (P=.004).

CONCLUSION

Among women with histories of preeclampsia, CIMT may identify those with subclinical atherosclerosis, thus offering an opportunity for early intervention.

ADAB2IPgenotype: sex interaction is associated with abdominal aortic aneurysm expansion

A faster expansion rate of abdominal aortic aneurysm (AAA) increases the risk of rupture. Women are at higher risk of rupture than men, but the mechanisms underlying this increased risk are unknown. We investigated whether genetic variants that influence susceptibility for AAA (CDKN2A-2B,SORT1,DAB2IP,LRP1andLDLR) are associated with AAA expansion and whether these associations differ by sex in 650 patients with AAA (mean age 70±8 years, 17% women) enrolled in the Mayo Clinic Vascular Disease Biorepository. Women had a mean aneurysm expansion 0.41 mm/year greater than men after adjustment for baseline AAA size. In addition to baseline size, mean arterial pressure (MAP), non-diabetic status,SORT1-rs599839[G] andDAB2IP-rs7025486[A] were associated with greater aneurysm expansion (all p<0.05). The associations of MAP and rs599839[G] were similar in both sexes, while the associations of baseline size, pulse pressure (PP) and rs7025486[A] were stronger in women than men (all p-sexinteraction≤0.02). A three-way interaction of PP*sex* rs7025486[A] was noted in a full-factorial analysis (p=0.007) independent of baseline size and MAP. In the high PP group (≥median), women had a mean growth rate 0.68 mm/year greater per [A] of rs7025486 than men (p-sexinteraction=0.003), whereas there was no difference in the low PP group (p-sexinteraction=0.8). We demonstrate that variantsDAB2IP-rs7025486[A] andSORT1-rs599839[G] are associated with AAA expansion. The association of rs7025486[A] is stronger in women than men and amplified by high PP, contributing to sex differences in aneurysm expansion.

Preeclampsia and cognitive impairment later in life

BACKGROUND

Hypertension is a risk factor for cerebrovascular disease and cognitive impairment. Women with hypertensive episodes during pregnancy report variable neurocognitive changes within the first decade following the affected pregnancy. However, long-term follow-up of these women into their postmenopausal years has not been conducted.

OBJECTIVE

The aim of this study was to examine whether women with a history of preeclampsia were at increased risk of cognitive decline 35-40 years after the affected pregnancy.

STUDY DESIGN

Women were identified and recruited through the medical linkage, population-based Rochester Epidemiologic Project. Forty women with a history of preeclampsia were age- and parity-matched to 40 women with a history of normotensive pregnancy. All women underwent comprehensive neuropsychological assessment and completed self-report inventories measuring mood, ie, depression, anxiety, and other symptoms related to emotional state. Scores were compared between groups. In addition, individual cognitive scores were examined by neuropsychologists and a neurologist blinded to pregnancy status, and a clinical consensus diagnosis of normal, mild cognitive impairment, or dementia for each participant was conferred.

RESULTS

Age at time of consent did not differ between preeclampsia (59.2 [range 50.9-71.5] years) and normotensive (59.6 [range 52.1-72.2] years) groups, nor did time from index pregnancy (34.9 [range 32.0-47.2] vs 34.5 [range 32.0-46.4] years, respectively). There were no statistically significant differences in raw scores on tests of cognition and mood between women with histories of preeclampsia compared to women with histories of normotensive pregnancy. However, a consensus diagnosis of mild cognitive impairment or dementia trended toward greater frequency in women with histories of preeclampsia compared to those with normotensive pregnancies (20% vs 8%, P = .10) and affected more domains among the preeclampsia group (P = .03), most strongly related to executive dysfunction (d = 1.96) and verbal list learning impairment (d = 1.93).

CONCLUSION

These findings suggest a trend for women with a history of preeclampsia to exhibit more cognitive impairment later in life than those with a history of normotensive pregnancy. Furthermore, the pattern of cognitive changes is consistent with that observed with vascular disease/white matter pathology.

Plasma orexin A levels in recently menopausal women during and 3 years following use of hormone therapy

OBJECTIVE

Alterations in sleep quality and metabolism during menopause are improved by menopausal hormone therapy (MHT). The mechanisms mediating these effects remain unclear. Orexin A (OxA) is a neuro-peptide that regulates sleep/wakefulness, food intake and metabolism. This study examined changes in plasma OxA levels during and after treatment in women from the Kronos Early Estrogen Prevention Study (KEEPS).

METHODS

KEEPS randomized women within three years of menopause to: oral conjugated equine estrogen (o-CEE, 0.45mg/day), transdermal 17β estradiol (t-E2, 50μg/day), or placebo pills and patches for four years. Plasma OxA levels were measured by enzyme immunoassays in fasting blood samples collected annually from KEEPS participants at Mayo Clinic during and three years after MHT. Changes in menopausal symptoms and plasma OxA levels were assessed for treatment differences.

RESULTS

During treatment, OxA levels increased more in women randomized to o-CEE compared with the other groups. Women randomized to either form of MHT demonstrated smaller increases in BMI than those on placebo. Insomnia severity decreased similarly among treatment groups. However, neither changes in sleep nor changes in BMI correlated with changes in plasma OxA levels. Changes in waist circumference correlated positively with changes in plasma OxA levels three years after discontinuation of study treatments.

CONCLUSIONS

Although OxA levels increased only in women randomized to o-CEE, these changes did not correlate with changes in sleep quality or BMI. The modest correlation of OxA levels with waist circumference once study treatments were discontinued suggests that OxA may be modulated through multiple intermediary pathways affected by metabolites of 17β-estradiol. Clinical Trial Registration for KEEPS: NCT00154180.

Risk of Heart Failure With Preserved Ejection Fraction in Older Women After Contemporary Radiotherapy for Breast Cancer

BACKGROUND

Cardiomyocytes are resistant to radiation. However, cardiac radiation exposure causes coronary microvascular endothelial inflammation, a perturbation implicated in the pathogenesis of heart failure (HF) and particularly HF with preserved ejection fraction (HFpEF). Radiotherapy for breast cancer results in variable cardiac radiation exposure and may increase the risk of HF.

METHODS

We conducted a population-based case-control study of incident HF in 170 female residents of Olmsted County, Minnesota (59 cases and 111 controls), who underwent contemporary (1998-2013) radiotherapy for breast cancer with computed tomography-assisted radiotherapy planning. Controls were matched to cases for age, tumor side, chemotherapy use, diabetes mellitus, and hypertension. Mean cardiac radiation dose (MCRD) in each patient was calculated from the patient's computed tomography images and radiotherapy plan.

RESULTS

Mean age at radiotherapy was 69±9 years. Of HF cases, 38 (64%) had EF≥50% (HFpEF), 18 (31%) had EF<50% (HF with reduced EF), and 3 (5%) did not have EF measured. The EF was ≥40% in 50 of the 56 HF cases (89%) with an EF measurement. The mean interval from radiotherapy to HF was 5.8±3.4 years. The odds of HF was higher in patients with a history of ischemic heart disease or atrial fibrillation. The MCRD was 2.5 Gy (range, 0.2-13.1 Gy) and higher in cases (3.3±2.7 Gy) than controls (2.1±2.0 Gy; P=0.004). The odds ratio (95% confidence interval) for HF per log MCRD was 9.1 (3.4-24.4) for any HF, 16.9 (3.9-73.7) for HFpEF, and 3.17 (0.8-13.0) for HF with reduced EF. The increased odds of any HF or HFpEF with increasing MCRD remained significant after adjustment for HF risk factors and in sensitivity analyses matching by cancer stage rather than tumor side. Only 18.6% of patients experienced new or recurrent ischemic events between radiotherapy and the onset of HF.

CONCLUSIONS

The relative risk of HFpEF increases with increasing cardiac radiation exposure during contemporary conformal breast cancer radiotherapy. These data emphasize the importance of radiotherapy techniques that limit MCRD during breast cancer treatment. Moreover, these data provide further support for the importance of coronary microvascular compromise in the pathophysiology of HFpEF.

Reasons for the persistent incidence of venous thromboembolism

Reasons for trends in venous thromboembolism (VTE) incidence are uncertain. It was our objective to determine VTE incidence trends and risk factor prevalence, and estimate population-attributable risk (PAR) trends for each risk factor. In a population-based cohort study of all residents of Olmsted County, Minnesota from 1981-2010, annual incidence rates were calculated using incident VTE cases as the numerator and age- and sex-specific Olmsted County population estimates as the denominator. Poisson regression models were used to assess the relationship of crude incidence rates to year of diagnosis, age at diagnosis, and sex. Trends in annual prevalence of major VTE risk factors were estimated using linear regression. Poisson regression with time-dependent risk factors (person-years approach) was used to model the entire population of Olmsted County and derive the PAR. The age- and sex-adjusted annual VTE incidence, 1981-2010, did not change significantly. Over the time period, 1988-2010, the prevalence of obesity, surgery, active cancer and leg paresis increased. Patient age, hospitalisation, surgery, cancer, trauma, leg paresis and nursing home confinement jointly accounted for 79 % of incident VTE; obesity accounted for 33 % of incident idiopathic VTE. The increasing prevalence of obesity, cancer and surgery accounted in part for the persistent VTE incidence. The PAR of active cancer and surgery, 1981-2010, significantly increased. In conclusion, almost 80 % of incident VTE events are attributable to known major VTE risk factors and one-third of incident idiopathic VTE events are attributable to obesity. Increasing surgery PAR suggests that concurrent efforts to prevent VTE may have been insufficient.

Genome-Wide and Gene-Based Meta-Analyses Identify Novel Loci Influencing Blood Pressure Response to Hydrochlorothiazide

This study aimed to identify novel loci influencing the antihypertensive response to hydrochlorothiazide monotherapy. A genome-wide meta-analysis of blood pressure (BP) response to hydrochlorothiazide was performed in 1739 white hypertensives from 6 clinical trials within the International Consortium for Antihypertensive Pharmacogenomics Studies, making it the largest study to date of its kind. No signals reached genome-wide significance (P<5×10-8), and the suggestive regions (P<10-5) were cross-validated in 2 black cohorts treated with hydrochlorothiazide. In addition, a gene-based analysis was performed on candidate genes with previous evidence of involvement in diuretic response, in BP regulation, or in hypertension susceptibility. Using the genome-wide meta-analysis approach, with validation in blacks, we identified 2 suggestive regulatory regions linked to gap junction protein α1 gene (GJA1) and forkhead box A1 gene (FOXA1), relevant for cardiovascular and kidney function. With the gene-based approach, we identified hydroxy-delta-5-steroid dehydrogenase, 3 β- and steroid δ-isomerase 1 gene (HSD3B1) as significantly associated with BP response (P<2.28×10-4 ). HSD3B1 encodes the 3β-hydroxysteroid dehydrogenase enzyme and plays a crucial role in the biosynthesis of aldosterone and endogenous ouabain. By amassing all of the available pharmacogenomic studies of BP response to hydrochlorothiazide, and using 2 different analytic approaches, we identified 3 novel loci influencing BP response to hydrochlorothiazide. The gene-based analysis, never before applied to pharmacogenomics of antihypertensive drugs to our knowledge, provided a powerful strategy to identify a locus of interest, which was not identified in the genome-wide meta-analysis because of high allelic heterogeneity. These data pave the way for future investigations on new pathways and drug targets to enhance the current understanding of personalized antihypertensive treatment.

Impact of Left Atrial Appendage Closure During Cardiac Surgery on the Occurrence of Early Postoperative Atrial Fibrillation, Stroke, and Mortality: A Propensity Score-Matched Analysis of 10 633 Patients

BACKGROUND

Prophylactic exclusion of the left atrial appendage (LAA) is often performed during cardiac surgery ostensibly to reduce the risk of stroke. However, the clinical impact of LAA closure in humans remains inconclusive.

METHODS

Of 10 633 adults who underwent coronary artery bypass grafting and valve surgery between January 2000 and December 2005, 9792 patients with complete baseline characteristics, surgery procedure, and follow-up data were included in this analysis. A propensity score-matching analysis based on 28 pretreatment covariates was performed and 461 matching pairs were derived and analyzed to estimate the association of LAA closure with early postoperative atrial fibrillation (POAF) (atrial fibrillation ≤30 days of surgery), ischemic stroke, and mortality.

RESULTS

In the propensity-matched cohort, the overall incidence of POAF was 53.9%. In this group, the rate of early POAF among the patients who underwent LAA closure was 68.6% versus 31.9% for those who did not undergo the procedure (P<0.001). LAA closure was independently associated with an increased risk of early POAF (adjusted odds ratio, 3.88; 95% confidence interval, 2.89-5.20), but did not significantly influence the risk of stroke (adjusted hazard ratio, 1.07; 95% confidence interval, 0.72-1.58) or mortality (adjusted hazard ratio, 0.92; 95% confidence interval, 0.75-1.13).

CONCLUSIONS

After adjustment for treatment allocation bias, LAA closure during routine cardiac surgery was significantly associated with an increased risk of early POAF, but it did not influence the risk of stroke or mortality. It remains uncertain whether prophylactic exclusion of the LAA is warranted for stroke prevention during non-atrial fibrillation-related cardiac surgery.

Impact of Stress Testing for Coronary Artery Disease Screening in Asymptomatic Patients With Diabetes Mellitus: A Community-Based Study in Olmsted County, Minnesota

OBJECTIVE

To evaluate the impact of screening stress testing for coronary artery disease in asymptomatic patients with diabetes in a community-based population.

PATIENTS AND METHODS

This observational study included 3146 patients from Olmsted County, Minnesota, with no history of coronary artery disease or cardiac symptoms in whom diabetes was newly diagnosed from January 1, 1992, through December 31, 2008. With combined all-cause mortality and myocardial infarction as the primary outcome, weighted Cox proportional hazards regression was performed with screening stress testing within 2 years of diabetes diagnosis as the time-dependent covariate. For descriptive analysis, participants were classified by their clinical experience during the first 2 years postdiagnosis as screened (asymptomatic, underwent stress test), unscreened (asymptomatic, no stress test), or symptomatic (experienced symptoms or event).

RESULTS

Among the screened and unscreened participants, 54% (1358 of 2538) were men; the mean (SD) age at diabetes diagnosis was 55 years (13.8 years), and 97% (2442 of 2520) had type 2 diabetes. In event-free survival analysis, 292 patients comprised the screened cohort and 2246 patients comprised the unscreened cohort. Death or myocardial infarction occurred in 454 patients (32 patients in the screened cohort and 422 in the unscreened cohort [5-year rate, 1.9% and 5.3%, respectively]) during median (interquartile range) follow-up of 9.1 years (5.3-12.5 years). Screening stress testing was associated with improved event-free survival (hazard ratio, 0.61; P=.004), independent of cardiac risk factors. However, while stress test results were abnormal in 47 of the 292 screened patients (16%), only 6 (2%) underwent coronary revascularization.

CONCLUSION

Although screening cardiac stress testing in asymptomatic patients with diabetes in this community-based population was associated with improvement in long-term event-free survival, this result does not appear to occur by coronary revascularization alone.

Comparison of Blood Pressure Control Rates Among Recommended Drug Selection Strategies for Initial Therapy of Hypertension

BACKGROUND

Several approaches to initiation of antihypertensive therapy have been suggested. These include thiazide diuretics (TDs) as the first drug in all patients, initial drug selection based on age and race criteria, or therapy selection based on measures of plasma renin activity (PRA). It is uncertain which of these strategies achieves the highest control rate with monotherapy in Stage-I hypertension. We sought to compare control rates among these strategies.

METHODS

We used data from the Pharmacogenomic Evaluation of Antihypertensive Responses study (PEAR) to estimate control rates for each strategy: (i) TD for all, (ii) age- and race-based strategy: Hydrochlorothiazide (HCTZ) for all blacks and for whites ≥50 years and a renin-angiotensin system inhibitor (atenolol) for whites <50 years) or (iii) a PRA based strategy: HCTZ for suppressed PRA (<0.6ng/ml/h) and atenolol for non-suppressed PRA (≥0.6ng/ml/h) despite age or race. Hypertension was confirmed prior to treatment with HCTZ (148 blacks and 218 whites) or with atenolol (146 blacks and 221 whites).

RESULTS

In the overall sample, using clinic blood pressure (BP) response, the renin-based strategy was associated with the greatest control rate (48.9% vs. 40.8% with the age and race-based strategy (P = 0.0004) and 31.7% with the TD for all strategy (P < 0.0001)). The findings were similar using home or by 24-hour ambulatory BP responses and within each racial subgroup.

CONCLUSIONS

A strategy for selection of initial antihypertensive drug therapy based on PRA was associated with greater BP control rates compared to a thiazide-for-all or an age and race-based strategy.

Pregnancy history and blood-borne microvesicles in middle aged women with and without coronary artery calcification

BACKGROUND AND AIMS

Having a history of preeclampsia increases the risk for future coronary artery calcification (CAC). This study evaluated the association of blood-borne, cell-derived microvesicles (MV) with CAC in middle-aged women.

METHODS

Twelve pre-selected, antigen-specific MV were measured by digital flow cytometry in the blood of age- and parity-matched women (median age 60 years) without a history of cardiovascular events, but with either a history of preeclampsia (PE, n = 39) or normotensive pregnancy (NP, n = 40). CAC was determined by computed tomography.

RESULTS

CAC scores ranged from 0 to 47 and 0-602 Agatston Units in the NP and PE groups, respectively. Waist circumference and insulin resistance were greatest in PE women with CAC. MV positive for tissue factor or stem/progenitor cell antigen (CD117) differed between NP and PE groups. In univariate analysis, those positive for tissue factor, ICAM-1, stem cells, and adipocytes (P16-set) antigens associated with CAC in the PE group. Principal components (PC) analysis reduced the MV variables to three independent dimensions. PC1 showed a modest correlation with CAC scores in the PE group (ρ = 0.31, p = 0.06) and associated with CAC in a multivariable model on pooled groups that included all 3 PC variables when adjusted for pregnancy status (p = 0.03). The association was lost when corrected for body mass index or waist circumference.

CONCLUSIONS

In women with a history of PE and elevated metabolic risk profile, a group of specific antigen-positive MV associated with CAC. These MV may reflect cellular processes associated with CAC. Their diagnostic potential for CAC remains to be determined.

Predictors of Failure of Endovascular Therapy for Peripheral Arterial Disease

The objective of this study was to assess the usefulness of a comparison of clinical failure and restenosis rates of endovascular procedures at 1 year in patients with peripheral arterial disease. The resulting comparison is presented as “clinical failure/restenosis coordinate.” The authors screened 171 papers describing the outcome of lower extremity angioplasty or stent placement. In 20 of them, authors reported detailed outcomes of interest, including baseline demographic measurements, location of arterial occlusive lesions, a measure of restenosis (measured by ankle-brachial indices, ultrasonography, or angiography), and clinical outcomes (mortality, repeat percutaneous transluminal angioplasty, or amputation). An overview of these 20 angioplasty papers was performed. Besides the usual meta-analyses of each end point separately, data were also plotted as coordinates of clinical failure versus restenosis. The clinical failure-to-restenosis coordinate was calculated and reported for percutaneous transluminal angioplasty of the aortoiliac and femoropopliteal distributions. Clinically reported outcomes in the literature were used to calculate the clinical failure/restenosis coordinate. This value was significantly different for various locations of the angioplasty and various baseline angiographic characteristics. A numeric coordinate pair of clinical failure and restenosis is identifiable in patients undergoing endovascular treatment of peripheral arterial disease. The varying coordinates may be important in elucidating the incidence and mechanisms of clinical failure after endovascular treatment. The coordinate reported in this article is hypothesis-generating about mechanisms of endovascular treatment failure. This coordinate is important in determining the role of restenosis in the clinical failure of endovascular therapy of peripheral arterial disease.