Surgical menopause increases salt sensitivity of blood pressure

Journal Article; Research Support, U.S. Gov't, Non-P.H.S.;Salt sensitivity of blood pressure is associated with an elevated risk of developing hypertension (HTN) and is an independent risk factor for cardiovascular disease. The prevalence of HTN increases after menopause. The aim of this study was to investigate prospectively whether the loss of ovarian hormones increases the occurrence of salt sensitivity among healthy premenopausal women. We enrolled 40 normotensive, nondiabetic women (age 47.2+/-3.5), undergoing hysterectomy-oophorectomy for nonneoplastic processes and not on hormone replacement, to determine the effect of changes in sodium intake on blood pressure the day before and subsequently 4 months after surgical menopause. Salt loading was achieved using a 2-L normal saline infusion and salt depletion produced by 40 mg of intravenous furosemide. A decrease >10 mm Hg in systolic blood pressure between salt loading and salt depletion was used to define salt sensitivity. Before and after menopause, salt-sensitive women exhibited higher waist/hip and waist/thigh ratios (P<0.01). Although all of the women remained normotensive, the prevalence of salt sensitivity was significantly higher after surgical menopause (21 women; 52.5%) than before (9 women; 22.5%; P=0.01), because 12 (38.7%) salt-resistant women developed salt sensitivity after menopause. In summary, we demonstrated that the prevalence of salt sensitivity doubled as early as 4 months after surgical menopause, without an associated increase in blood pressure. Epidemiological studies indicate that development of HTN may not occur until 5 to 10 years after menopause. The loss of ovarian hormones may unmask a population of women prone to salt sensitivity who, with aging, would be at higher risk for the subsequent development of HTN and cardiovascular disease.This work was supported by funds from the Veterans Affairs Administration to L.R.Ye

Smoking patterns and chronic kidney disease in US Hispanics: Hispanic Community Health Study/Study of Latinos

Intermittent smoking is prevalent among Hispanics, but little is known about whether this smoking pattern associates with increased chronic kidney disease (CKD) risk in this population. The objective of the present study is to identify patterns of exposure associated with CKD in US Hispanics

Glomerular thrombosis in pregnancy: Role of the L-arginine-nitric oxide pathway

Glomerular thrombosis in pregnancy: Role of the L-arginine-nitric oxide pathway. E. coli endotoxin (LPS) and certain cytokines induce synthesis of nitric oxide (NO) from L-arginine, but also promote endothelial injury and intravascular coagulation. NO has vasodilator and antithrombogenic properties. We investigated the relationship between the L-arginine-NO pathway and the susceptibility to LPS-induced glomerular thrombosis in pregnancy. Pregnant rats were given either 0.15 or 0.75 mg/kg/body wt of LPS intraperitoneally. In rats given 0.15 mg/kg/body wt of LPS urinary NO2−/NO3− (end products of NO) increased 200% (P < 0.05), plasma L-arginine did not change, and glomerular thrombosis was minimal. Pregnant rats given 0.75 mg/kg/body wt of LPS developed glomerular thrombosis in 75% of glomeruli (P < 0.05). In these rats plasma L-arginine fell 98%, from 53 ± 4 to 1.4 ± 0.9 mmol/liter (P < 0.05) but the urinary NO2−/NO3− did not increase. Oral administration of L-arginine but not D-arginine increased urinary NO2−/NO3− by 250% and averted glomerular thrombosis in these rats (P < 0.05). Virgin rats given 0.75 mg/kg/body wt of LPS did not contract glomerular thrombosis. In these rats plasma L-arginine decreased only 40% while urinary NO2−/NO3− concomitantly increased over 200% (P < 0.05). Plasma endothelin-1 increased only in rats exhibiting glomerular thrombosis. Thus, limited maternal reserve capability for NO synthesis may underlie, at least in part, the susceptibility for glomerular thrombosis in pregnancy

Major and Minor Electrocardiographic Abnormalities and Their Association With Underlying Cardiovascular Disease and Risk Factors in Hispanics/Latinos (from the Hispanic Community Health Study/Study of Latinos)

The association of ECG abnormalities with cardiovascular disease and risk factors has been extensively studied in Whites and African Americans. Comparable data have not been reported in Hispanics/Latinos. The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) is a multicenter community based prospective cohort study of men and women of diverse backgrounds ages 18 to 74 years who self-identified as Hispanic/Latinos. Participants (N=16,415), enrolled between March 2008 and June 2011. We describe the prevalence of minor and major ECG abnormalities and examine their cross-sectional associations with cardiovascular disease and risk factors. The Minnesota code criteria were used to define minor and major abnormalities of the ECG. Prior cardiovascular disease and risk factors were based on data obtained at baseline examination. Significant differences in prevalent ECG findings were found between men and women. Major ECG abnormalities were present in 9.2 %( 95% confidence interval [CI], 8.3–10.1) of men and 6.6% (95% CI, 5.8–7.3) of women (P<.0001). The odds of having major ECG abnormalities significantly increased with age, presence of 3 or more cardiovascular risk factors and prevalent cardiovascular disease, in both men and women. Significant differences in major ECG abnormalities were found among the varying groups; Puerto Ricans and Dominicans had more major abnormalities compared to Mexican men and women. In conclusion, a large cohort of Hispanic/Latino men and women, prevalence of major abnormalities were low yet strong associations of major ECG abnormalities with cardiovascular disease and risk factors were observed in both men and women

Acculturation and chronic kidney disease in the Hispanic community health study/study of Latinos (HCHS/SOL)

Hispanics/Latinos are burdened by chronic kidney disease (CKD). The role of acculturation in this population has not been explored. We studied the association of acculturation with CKD and cardiovascular risk factor control. We performed cross-sectional analyses of 13,164 U.S. Hispanics/Latinos enrolled in the HCHS/SOL Study between 2008 and 2011. Acculturation was measured using the language and ethnic social relations subscales of the Short Acculturation Scale for Hispanics, and proxies of acculturation (language preference, place of birth and duration of residence in U.S.). CKD was defined as estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2 or urine albumin-to-creatinine ratio ≥ 30 mg/g. On multivariable analyses stratified by age, lower language subscale score was associated with higher odds of CKD among those older than 65 (OR 1.29, 95% CI, 1.03, 1.63). No significant association was found between proxies of acculturation and CKD in this age strata. Among individuals aged 18–44, a lower language subscale score was associated with lower eGFR (β = −0.77 ml/min/1.73 m2, 95% CI −1.43, −0.10 per 1 SD increase) and a similar pattern was observed for ethnic social relations. Among those older than 65, lower language subscale score was associated with higher log-albuminuria (β = 0.12, 95% CI 0.03, 0.22). Among individuals with CKD, acculturation measures were not associated with control of cardiovascular risk factors. In conclusion, lower language acculturation was associated with a higher prevalence of CKD in individuals older than 65. These findings suggest that older individuals with lower language acculturation represent a high risk group for CKD

Prevalence of Hypertension, Awareness, Treatment, and Control in the Hispanic Community Health Study/Study of Latinos

The prevention and control of hypertension is an essential component for reducing the burden of cardiovascular diseases. Here we describe the prevalence of hypertension in diverse Hispanic/Latino background groups and describe the proportion who are aware of their diagnosis, receiving treatment, and having their hypertension under control

Design and Implementation of the Hispanic Community Health Study/Study of Latinos

The Hispanic Community Health Study (HCHS)/Study of Latinos (SOL) is a comprehensive multi-center community based cohort study of Hispanics/Latinos in the United States. Its rationale, objectives, design and implementation are described in this paper

Nitric oxide in the pathogenesis of cardiac disease

Endothelial dysfunction is characterized by a vasoconstrictive and prothrombotic state in the vasculature; it plays a role in all stages of cardiac disease and is a significant independent predictor of cardiovascular outcomes. Nitric oxide (NO) performs multiple biologic activities in the endothelium, including vasodilation and antithrombotic actions. Reduced NO bioactivity is a major component of endothelial dysfunction. Impaired NO bioactivity is an important factor in the pathogenesis of atherosclerosis and in the metabolic syndrome. The functions of NO bioactivity in the heart go well beyond those in the endothelium, as all 3 NO synthase (NOS) isoforms-endothelial NOS, neuronal NOS, and inducible NOS-are expressed in cardiac myocytes and mediate systolic, diastolic, and chronotropic cardiac functions. Impairment of NO bioactivity is a pathogenic factor in various forms of cardiac disease. Although these findings support the potential use of NO-targeted therapies for treatment of cardiac disease, the complexities of the biologic actions of NO in the vasculature and heart are such that development of therapies is still largely in the preliminary stages