Gender difference in cardiovascular risk factors in the elderly with cardiovascular disease in the last stage of lifespan: The PROTEGER study

Gender differences in the relationship between serum uric acid and the long-term prognosis in heart failure: a nationwide study

BACKGROUND

Serum uric acid (SUA) is an important pathogenetic and prognostic factor for heart failure (HF). Gender differences are apparent in HF. Furthermore, gender differences also exist in the association between SUA and prognosis in various cardiovascular diseases. However, the gender difference for SUA in the prediction of long-term prognosis in HF is still ambiguous.

METHODS

A total of 1593 HF patients (897 men, 696 women) from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 cycle were enrolled in our final analysis. Participants were categorized according to gender-specific SUA tertile. We assessed the association between SUA and long-term prognosis of HF patients, defined as all-cause mortality and cardiovascular mortality, in different genders via Kaplan-Meier curve analysis, Cox proportional hazard model, and Fine-Gray competing risk model. The restricted cubic spline (RCS) was performed to investigate the dose-response relationship between SUA and outcomes.

RESULTS

Gender differences exist in demographic characteristics, clinical parameters, laboratory tests, and medication of HF patients. After a median follow-up of 127 months (95% CI 120-134 months), there were 853 all-cause deaths (493 events in men, 360 events in women) and 361 cardiovascular deaths (206 events in men, 155 events in women). Kaplan-Meier analysis showed that SUA had gender difference in the prediction of cardiovascular mortality (Log-rank p < 0.001, for male, Log-rank p = 0.150, for female), but not in all-cause mortality. Multivariate Cox regression analysis revealed that elevated SUA levels were associated with higher all-cause mortality and cardiovascular mortality in men (HR 1.11, 95% CI 1.05-1.18, p < 0.001, for all-cause death; HR 1.18, 95% CI 1.09-1.28, p < 0.001, for cardiovascular death), but not in women (HR 1.05, 95% CI 0.98-1.12, p = 0.186, for all-cause death; HR 1.01, 95% CI 0.91-1.12, p = 0.902, for cardiovascular death). Even using non-cardiovascular death as a competitive risk, adjusted Fine-Gray model also illustrated that SUA was an independent predictor of cardiovascular death in men (SHR 1.17, 95% CI 1.08-1.27, p < 0.001), but not in women (SHR 0.98, 95% CI 0.87 - 1.10, p = 0.690).

CONCLUSIONS

Gender differences in the association between SUA and long-term prognosis of HF existed. SUA was an independent prognostic predictor for long-term outcomes of HF in men, but not in women.

1H-NMR metabolomics-based surrogates to impute common clinical risk factors and endpoints

Background

Missing or incomplete phenotypic information can severely deteriorate the statistical power in epidemiological studies. High-throughput quantification of small-molecules in bio-samples, i.e. ‘metabolomics’, is steadily gaining popularity, as it is highly informative for various phenotypical characteristics. Here we aim to leverage metabolomics to impute missing data in clinical variables routinely assessed in large epidemiological and clinical studies.

Methods

To this end, we have employed ∼26,000 ¹H-NMR metabolomics samples from 28 Dutch cohorts collected within the BBMRI-NL consortium, to create 19 metabolomics-based predictors for clinical variables, including diabetes status (AUC_{5-Fold CV} = 0·94) and lipid medication usage (AUC_{5-Fold CV} = 0·90).

Findings

Subsequent application in independent cohorts confirmed that our metabolomics-based predictors can indeed be used to impute a wide array of missing clinical variables from a single metabolomics data resource. In addition, application highlighted the potential use of our predictors to explore the effects of totally unobserved confounders in omics association studies. Finally, we show that our predictors can be used to explore risk factor profiles contributing to mortality in older participants.

Interpretation

To conclude, we provide ¹H-NMR metabolomics-based models to impute clinical variables routinely assessed in epidemiological studies and illustrate their merit in scenarios when phenotypic variables are partially incomplete or totally unobserved.

Funding

BBMRI-NL, X-omics, VOILA, Medical Delta and the Dutch Research Council (NWO-VENI).

Longitudinal Changes in Mean and Pulse Pressure, and All-Cause Mortality: Data From 71,629 Untreated Normotensive Individuals

BACKGROUND

Blood pressure (BP) includes a steady (mean arterial pressure, MAP) and a pulsatile component that independently predict mortality. The association between longitudinal changes in central (c) pulse pressure (PP), brachial (b) PP, MAP, and incident mortality has never been investigated in this context.

METHODS

Brachial MAP and PP were measured at 2 routine checkups (1st visit 1992; mean interval, 5.8 ± 2.4 years) in 71,629 individuals, age 16-95 years, none on antihypertensive drugs. cPP was estimated with a validated algorithm. Each change (visit 2-1) in bPP, cPP, and MAP, expressed in mm Hg/year, was categorized as: increase, decrease, or no-change, with the latter representing the control-group. Follow-up data (6.9 ± 3.3 years) on all-cause mortality (2,033 deaths) were documented.

RESULTS

All-cause mortality Cox regression models adjusted for confounders showed that compared to the subgroup with steady BP at both visits, the subgroup with: (i) increased bPP or cPP had an approximately 200% increase in relative risk (RR); (ii) decreased cPP and bPP had a 15% reduction in RR; (iii) increased MAP had a 68% increase in RR; (iv) decreased MAP had a 7% increase in RR of mortality. Interaction analysis stratified by gender showed that annual increases in PP, but not MAP, were greater in younger than older men and lower in younger than older women. Age cutoff value was 55 years.

CONCLUSIONS

MAP and PP have distinct characteristics affecting all-cause mortality. PP integrates the effects of age and gender on all-cause mortality more notably than MAP, thus impacting significantly on cardiovascular risk.

Sex-dependent difference in the relationship between adipose-tissue cholesterol efflux and estradiol concentrations in young healthy humans

BACKGROUND

Impaired adipose tissue function and lower levels of high density lipoprotein cholesterol (HDL-C) have been implicated in the development of vascular dementia, and metabolic diseases such as hypertension, atherosclerosis, type 2 diabetes (T2D) and metabolic syndrome. Interestingly, both the substrate fluxes in adipose tissue and HDL-C concentration differ between men and women. Moreover, adipose tissue cholesterol efflux has been implicated in modulation of HDL-C levels. Thus, we aimed to determine if the association between serum estradiol levels and adipose tissue cholesterol efflux is sex-dependent.

METHOD

We evaluated the serum estradiol levels and adipose tissue cholesterol efflux in young healthy men (n=5) and women (n=3). Adipose tissue cholesterol efflux was determined using subcutaneous microdialysis probes. Linear regression analyses were used to determine the relationship between the parameters, p<0.05 was considered as statistically significant.

RESULTS

Our data demonstrated that serum estradiol levels directly associated with adipose tissue cholesterol efflux; however, the relationships may be sex-dependent. We discussed our results in the context of currently available data regarding sex-dependent variability in adipose tissue function and HDL-C metabolism as a potential contributor to higher rates of vascular dementia in men. Further research is required to understand the sex-dependent and -independent variabilities in adipose tissue metabolism to determine novel targets for interventions to prevent the development of vascular dementia.

Evidence for a Prognostic Role of Orthostatic Hypertension on Survival in a Very Old Institutionalized Population

In old individuals, regulation of blood pressure during postural changes is impaired. Several studies have assessed the clinical impact of orthostatic hypotension (OHypoT) during the aging process. By contrast, the prevalence and prognostic role of the increase in blood pressure in upright position (orthostatic hypertension, OHyperT) in old adults remain unknown. We investigated the association of OHyperT with cardiovascular morbidity and mortality in a population of old institutionalized subjects. A 2-year follow-up longitudinal study was conducted on 972 subjects (mean age [SD] 88 [5]) from the PARTAGE (Predictive Values of Blood Pressure and Arterial Stiffness in Institutionalized Very Aged Population) study, able to maintain a standing position. OHyperT was defined as an increase in systolic blood pressure ≥20 mm Hg during the first and third minute of standing. Three groups of subjects were compared: orthostatic normotension (n=540), OHypoT (n=157), and OHyperT (n=275). OHyperT prevalence (28%) was higher than OHypoT (16%). Sitting systolic blood pressure was higher in OHypoT compared with orthostatic normotension and OHyperT groups (146 [23] versus 136 [21] and 136 [20] mm Hg, respectively, P<0.001). The OHyperT group was associated with a greater risk of cardiovascular morbidity and mortality than orthostatic normotension (hazard ratio 1.51 [1.09-2.08], P<0.01) and remained unchanged after adjustment for age, sex, sitting systolic blood pressure, and comorbidities. No difference in cardiovascular morbidity and mortality was observed between OHyperT and OHypoT groups. In conclusion, in a old frail population, the increase in systolic blood pressure during upright position occurs frequently and is associated with higher cardiovascular morbidity and mortality independently of sitting blood pressure levels and major comorbidities. Health professional should take into account not only the decrease but also the increase in blood pressure when standing up.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00901355.

Elderly Algerian women lose their sex-advantage in terms of arterial stiffness and cardiovascular profile

OBJECTIVES

Several studies have shown lower carotid-femoral pulse wave velocity (cfPWV) levels in women compared to men, a difference that could partially explain the increased longevity in women. However, these studies have been performed in industrial countries while few data are available in emerging populations. We studied arterial stiffness, as evaluated by cfPWV, in elderly Algerian men and women.

METHODS

cfPWV was studied in 321 Algerian men (81.2 ± 5.3 years) and women (81.1 ± 4.4 years). An age-matched and sex-matched cohort of European individuals (n = 321) was used as a control group.

RESULTS

Comparatively to men, Algerian women exhibited higher BMI and heart rate (HR), higher prevalence of hypertension, and were more frequently treated for hypertension. cfPWV was not different between Algerian men (14.8 ± 3.3 m/s) and women (14.9 ± 3.4 m/s). By contrast, in Europeans, women had lower cfPWV (12.7 ± 2.7 m/s) than men (14.0 ± 3.3 m/s; P <0.001). Comparatively to European women, Algerian women had a higher cfPWV (P <0.01). In both ethnic groups, multivariate analyses revealed that age, mean blood pressure (BP), HR, and diabetes were positively associated with cfPWV, whereas female sex was associated with lower cfPWV only in Europeans.

CONCLUSION

Elderly Algerian women exhibit arterial stiffness similar to men, whereas European women display lower arterial stiffness than men. This loss of 'arterial sex advantage' in Algerians may be explained by higher BP, HR, and a worse metabolic profile in Algerian women. Interventions in emerging populations, especially in women, should be a priority in order to address these risk factors by acting on current lifestyle.

Total arterial compliance estimated by a novel method and all-cause mortality in the elderly: the PROTEGER study

Aortic stiffness, assessed by carotid-to-femoral pulse wave velocity (PWV), often fails to predict cardiovascular (CV) risk and mortality in the very elderly. This may be due to the non-linear association between PWV and compliance or to blood pressure decrease in the frailest subjects. Total arterial compliance (C T) is the most relevant arterial property regarding CV function, compared to local or regional arterial stiffness. A new method for C T estimation, based on PWV, was recently proposed. We aimed to investigate the value of C T to predict all-cause mortality at the elderly. PWV was estimated in 279 elderly subjects (85.5 ± 7.0 years) who were followed up for a mean period of 12.8 ± 6.3 months. C T was estimated by the formula C T = k × PWV(-2); coefficient k is body-size dependent based on previous in silico simulations. Herein, k was adjusted for body mass index (BMI) with a 10 % change in BMI corresponding to almost 11 % change in k. For a reference BMI = 26.2 kg/m(2), k = 37. Survivors (n = 185) and non-survivors (n = 94) had similar PWV (14.2 ± 3.6 versus 14.9 ± 3.8 m/s, respectively; p = 0.139). In contrast, non-survivors had significantly lower C T than survivors (0.198 ± 0.128 versus 0.221 ± 0.1 mL/mmHg; p = 0.018). C T was a significant predictor of mortality (p = 0.022, odds ratio = 0.326), while PWV was not (p = 0.202), even after adjustment for gender, mean pressure and heart rate. Age was an independent determinant of C T (p = 0.016), but not of PWV. C T, estimated by a novel method, can predict all-cause mortality in the elderly. C T may be more sensitive arterial biomarker than PWV regarding CV risk assessment.

Pulsatile hemodynamics and cardiovascular risk factors in very old patients: background, sex aspects and implications

BACKGROUND

In the nineteenth century, prior to the introduction of the cuff sphygmomanometer, stiffening of arteries was recognized as an indicator of vascular ageing and cardiovascular risk. Through the twentieth century, views on vascular ageing came to focus on brachial blood pressures and on occlusive atherosclerotic disease. Such focus deflected attention from primary ageing changes, represented by stiffening and dilation of the proximal aorta.

AIM

This review emphasizes the cushioning function of elastic arteries, principally the aorta, now when life expectancy largely exceeds 80 years providing new challenges for medical treatment in the very old.

METHODS AND RESULTS

First, life expectancy has increased significantly for both sexes and is particularly prolonged after menopause. Second, phenotypic changes are noticed such as that the age-related increase of waist circumference and hyperlipidemia is markedly slowed, whereas the concomitant rise in C-reactive protein is enhanced and hyperglycaemia develops in many patients. Third, the systolic, diastolic and pulse pressures rise with age is attenuated or even stopped, as is the degree of arterial stiffness. Finally, in very old patients, the main causes of death are cardiovascular, including cardiac deaths, which differ markedly by causation in men (due to lowered ejection fraction) and women (due to arrhythmia disorders). Deaths associated with renal impairment are observed in both sexes.

CONCLUSION

No simple linear relationships exist between all these phenotypic variables and the ageing process. Treatment goals of hypertension and diabetes mellitus remain difficult to predict from such data. Prevention of cardiovascular risk in the very old is thus influenced by limited evidence and important ethical considerations.