Microalbuminuria in hypertension

Lipid metabolism disorders and albuminuria risk: insights from National Health and Nutrition Examination Survey 2001-2018 and Mendelian randomization analyses

BACKGROUND

Previous studies have revealed an underlying connection between abnormal lipid metabolism and albuminuria. We aim to investigate the causal relationship between lipid metabolism disorders and the risk of albuminuria from both a population and genetic perspective.

METHODS

A cross-sectional study was conducted by using data from the National Health and Nutrition Examination Survey (NHANES) 2001-2018. Multivariable-adjusted logistic regression, subgroup analysis, interaction tests and restricted cubic spline (RCS) were employed statistically. Mendelian randomization (MR) analysis was performed to validate the causal relationship between exposure and outcome to mitigate confounding factors and reverse causation interference.

RESULTS

After adjusting for confounders, HDL levels (1.03-2.07 nmol/L) were associated with a reduced risk of albuminuria. In contrast, elevated cholesterol levels (>6.2 nmol/L) and triglyceride levels (>2.3 nmol/L) were associated with an increased risk of albuminuria. Serum triglyceride concentration emerged as a potential risk factor for albuminuria. In MR analysis, a reduced risk of albuminuria was associated with serum total HDL level (IVW: OR = 0.91, 95% CI = 0.86-0.97, p = 0.002). In contrast, cholesterol esters in medium VLDL (IVW: OR = 1.05, 95% CI = 1.00-1.10, p = 0.032), chylomicrons and extremely large VLDL (IVW: OR = 1.08, 95% CI = 1.03-1.14, p = 0.003), and triglycerides (IVW: OR = 1.14, 95% CI = 1.09-1.19, p < 0.001) were associated with an increased risk of albuminuria.

CONCLUSION

A causal relationship exists between serum lipid metabolism disorder and albuminuria risk. Further validation of additional blood lipid metabolism biomarkers is imperative for future studies.

Association of microalbuminuria and adverse outcomes in hypertensive patients: a meta-analysis

BACKGROUND

Studies on the association of microalbuminuria with adverse outcomes in patients with hypertension remain controversial. This meta-analysis aimed to assess the predictive value of microalbuminuria in hypertensive patients.

METHODS

PubMed and Embase databases were comprehensively searched for studies that published from their inceptions to July 10, 2020. Observational studies reporting the association of microalbuminuria (defined as urinary albumin excretion 30 and 300 mg/24 h urine or albumin/creatinine ratio 30-300 mg/g from a spot urine or equivalent value) with all-cause mortality or major adverse cardiovascular events (MACEs) in hypertensive patients were selected.

RESULTS

Nine studies with a total of 19,893 hypertensive patients were included. When compared with those without microalbuminuria, hypertensive patients with microalbuminuria had an increased risk of all-cause mortality (risk ratio [RR] 1.68; 95% confidence interval [CI] 1.46-1.93) and MACEs (RR 1.40; 95% CI 1.22-1.62), respectively. Gender-specific analysis indicated that microalbuminuria was significantly associated with an increased risk of all-cause mortality (RR 1.61; 95% CI 1.17-2.21) in men but not in women (RR 1.18; 95% CI 0.78-1.80).

CONCLUSION

This meta-analysis suggests that microalbuminuria is independently associated with higher risk of MACEs and all-cause mortality in hypertensive patients. Determination of microalbuminuria has potential to improve the risk classification of hypertension.

Per- and polyfluoroalkyl substances and kidney function: Follow-up results from the Diabetes Prevention Program trial

Per- and polyfluoroalkyl substances (PFAS) are ubiquitously detected in populations worldwide and may hinder kidney function. The objective of the study was to determine longitudinal associations of plasma PFAS concentrations with estimated glomerular filtration rate (eGFR) and evaluate whether a lifestyle intervention modify the associations. We studied 875 participants initially randomized to the lifestyle or placebo arms in the Diabetes Prevention Program (DPP, 1996-2002) trial and Outcomes Study (DPPOS, 2002-2014). We ran generalized linear mixed models accounting a priori covariates to evaluate the associations between baseline PFAS concentrations and repeated measures of eGFR, separately, for six PFAS (PFOS, PFOA, PFHxS, EtFOSAA, MeFOSAA, PFNA); then used quantile-based g-computation to evaluate the effects of the six PFAS chemicals as a mixture. The cohort was 64.9% female; 73.4% 40-64 years-old; 29.4% with hypertension; 50.5% randomized to lifestyle intervention and 49.5% to placebo and had similar plasma PFAS concentrations as the general U.S. population in 1999-2000. Most participants had normal kidney function (eGFR > 90 mL/min/1.73 m²) over the approximately 14 years of follow-up. We found that plasma PFAS concentrations during DPP were inversely associated with eGFR during DPPOS follow-up. Each quartile increase in baseline plasma concentration of the 6 PFAS as a mixture was associated with 2.26 mL/min/1.73 m² lower eGFR (95% CI: -4.12, -0.39) at DPPOS Year 5, approximately 9 years since DPP randomization and PFAS measurements. The lifestyle intervention did not modify associations, but inverse associations were stronger among participants with hypertension at baseline. Among prediabetic adults, we found inverse associations between baseline plasma PFAS concentrations and measures of eGFR throughout 14 years of follow-up. The lifestyle intervention of diet, exercise and behavioral changes did not modify the associations, but persons with hypertension may have heightened susceptibility.

ACVIM consensus statement: Guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats

An update to the 2007 American College of Veterinary Internal Medicine (ACVIM) consensus statement on the identification, evaluation, and management of systemic hypertension in dogs and cats was presented at the 2017 ACVIM Forum in National Harbor, MD. The updated consensus statement is presented here. The consensus statement aims to provide guidance on appropriate diagnosis and treatment of hypertension in dogs and cats.

Valsartan in combination with lisinopril versus the respective high dose monotherapies in hypertensive patients with microalbuminuria: the VALERIA trial

OBJECTIVES

Microalbuminuria is known as an independent predictor for stroke, myocardial infarction, and death. The purpose of the VALERIA trial was a comparison of the efficacy and safety of combination therapy of valsartan and lisinopril with valsartan and lisinopril high-dose monotherapy in patients with hypertension and microalbuminuria.

METHODS

This was a randomized, double-blind, interventional, parallel-group study. After a washout/placebo-run-in phase of 3 weeks, 133 patients were randomized to treatment (1: 1:1) with either lisinopril 40 mg, valsartan 320 mg, or a combination of valsartan/lisinopril 320/20 mg for 30 weeks.

RESULTS

At baseline, the urine albumin creatinine ratio was similar for the three treatment groups (geometric means, lisinopril 9.6 mg/mmol, valsartan 9.1 mg/mmol, and valsartan/lisinopril 9.5 mg/mmol). After 30 weeks of treatment, the geometric mean urine albumin creatinine ratio had decreased in all three groups by 41, 51, and 62% to 5.7 mg/mmol (lisinopril), 4.5 mg/mmol (valsartan), and 3.6 mg/mmol (valsartan/lisinopril). The decrease for valsartan/lisinopril was statistically significantly greater compared with lisinopril [adjusted ratio 60%, confidence interval (38-94%), P = 0.029]. Normalization of microalbuminuria was greatest with valsartan and valsartan/lisinopril (lisinopril 17%, valsartan 31%, and valsartan/lisinopril 38% of patients) and was statistically significant for lisinopril in contrast with valsartan/lisinopril (P = 0.034). Differences in blood pressure reduction between the groups were not statistically significant. All treatments were safe and well tolerated.

CONCLUSION

The combination of valsartan and lisinopril provided a significantly better reduction of urine albumin creatinine ratio and more than doubled the rate of patients with normalized urine albumin creatinine ratio compared with lisinopril alone. All treatments were safe and well tolerated.

Baseline albuminuria predicts the efficacy of blood pressure-lowering drugs in preventing cardiovascular events

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Albuminuria has been proven to be associated with cardiovascular morbidity and mortality. Such an association has been found not only in subjects with diabetes and hypertension, but also in the general population. It could therefore be expected that especially subjects with higher albuminuria levels may benefit from blood pressure-lowering agents to improve their cardiovascular outcome.

WHAT THIS STUDY ADDS

This study indicates that the efficacy of blood pressure-lowering agents to prevent cardiovascular events is dependent of the level of albuminuria before start of such treatment. The higher baseline albuminuria, the better the relative and absolute risk reduction for cardiovascular events with blood pressure-lowering drugs. The data also suggest a possible better cardiovascular protective effect of renin-angiotensin intervening agents compared with other blood pressure-lowering agents.

AIMS

Albuminuria has been proven to be associated with cardiovascular (CV) events in specific patient populations, but also in the general population. This study aimed to investigate whether the efficacy of blood pressure-lowering agents in preventing CV events depends on baseline urinary albumin excretion (UAE) and, if so, whether this holds true for blood pressure-lowering agents in general, or is limited to agents that interfere in the renin-angiotensin system.

METHODS

Data were used from a community-based cohort study and pharmacy dispensing records. Included were subjects with hypertension (systolic blood pressure >or=140 and/or diastolic blood pressure >or=90 mmHg), no cardiovascular disease history, and no previous use of blood pressure-lowering agents.

RESULTS

During study follow-up (7.1 +/- 1.6 years), 122 CV events were observed in 1185 subjects included. Start of blood pressure-lowering agents vs. non-use was associated with a difference in absolute CV event risk of 0.7%, 6% and 12.6% for all subjects, those with UAE >or= 15 mg day(-1) and >or=30 mg day(-1), respectively. Cox regression analysis showed that the relative risk for CV events after start of blood pressure-lowering agents was significantly dependent (P < 0.05) on baseline UAE; with hazard ratios of 0.87 [95% confidence interval (CI) 0.48, 1.60, P = NS], 0.58 (95% CI 0.36, 0.94, P < 0.05) and 0.37 (95% CI 0.20, 0.68, P < 0.05), for subjects with UAE < 15, >or=15 and >or=30 mg day(-1), respectively. Results adjusted for covariates were essentially similar. The use of angiotensin converting enzyme inhibitor/angiotensin-II receptor blocker (ACEi/ARB) treatment tended to be associated with a more favourable CV prognosis when compared with non-ACEi/ARB treatment (difference P = 0.06).

CONCLUSIONS

Our results suggest that the efficacy of blood pressure-lowering agents to prevent CV events is dependent on baseline albuminuria. The higher baseline albuminuria, the more absolute as well as relative risk reduction can be achieved. Our data suggest that this may especially be true for ACEi/ARBs. We caution that this is an observational study, and that these conclusions should therefore be regarded as hypothesis generating, rather than hypothesis testing.

Type of renal calculi: variation with age and sex

The aim of this paper is to study the variations in the percentage of the different types of renal stones with age and sex. Renal calculi were classified according to their composition and structure. Stone formers were divided according to age and sex, and the percentage of each kind of calculi in the different considered age periods for men and women were determined. It was found that calcium oxalate dihydrate calculi decreased with age, but only in men. These calculi were also clearly predominant in men. Hydroxyapatite calculi decreased with age in both men and women, but they were predominant in women. Uric acid calculi increased with age in both men and women, but were predominant in men. Finally, it was found that calcium oxalate monohydrate unattached calculi increased with age in both men and women. As a main novelty, the study here presented demonstrates the importance of distinguishing between calcium oxalate monohydrate papillary stones and calcium oxalate monohydrate unattached stones, since the etiologic factors responsible for their origin must be clearly different.

Renal damage in primary aldosteronism: results of the PAPY Study

Primary aldosteronism (PA) has been associated with cardiovascular hypertrophy and fibrosis, in part independent of the blood pressure level, but deleterious effects on the kidneys are less clear. Likewise, it remains unknown if the kidney can be diversely involved in PA caused by aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism (IHA). Hence, in the Primary Aldosteronism Prevalence in Italy (PAPY) Study, a prospective survey of newly diagnosed consecutive patients referred to hypertension centers nationwide, we sought signs of renal damage in patients with PA and in comparable patients with primary hypertension (PH). Patients (n = 1180) underwent a predefined screening protocol followed by tests for confirming PA and identifying the underlying adrenocortical pathology. Renal damage was assessed by 24-hour urine albumin excretion (UAE) rate and glomerular filtration rate (GFR). UAE rate was measured in 490 patients; all had a normal GFR. Of them, 31 (6.4%) had APA, 33 (6.7%) had IHA, and the rest (86.9%) had PH. UAE rate was predicted (P < 0.001) by body mass index, age, urinary Na+ excretion, serum K+, and mean blood pressure. Covariate-adjusted UAE rate was significantly higher in APA and IHA than in PH patients; there were more patients with microalbuminuria in the APA and IHA than in the PH group (P = 0.007). Among the hypertensive patients with a preserved GFR, those with APA or IHA have a higher UAE rate than comparable PH patients. Thus, hypertension because of excess autonomous aldosterone secretion features an early and more prominent renal damage than PH.

Racial and Ethnic Differences in Microalbuminuria Prevalence in a Diabetes Population: The Pathways Study

The objective of this study was to determine whether racial or ethnic differences in prevalence of diabetic microalbuminuria were observed in a large primary care population in which comparable access to health care exists. A cross-sectional analysis of survey and automated laboratory data 2969 primary care diabetic patients of a large regional health maintenance organization was conducted. Study data were analyzed for racial/ethnic differences in microalbuminuria (30 to 300 mg albumin/g creatinine) and macroalbuminuria (>300 mg albumin/g creatinine) prevalence among diabetes registry-identified patients who completed a survey that assessed demographics, diabetes care, and depression. Computerized pharmacy, hospital, and laboratory data were linked to survey data for analysis. Racial/ethnic differences in the odds of microalbuminuria and macroalbuminuria were assessed by unconditional logistic regression, stratified by the presence of hypertension. Among those tested, the unadjusted prevalence of micro- or macroalbuminuria was 30.9%, which was similar among the various racial/ethnic groups. Among those without hypertension, microalbuminuria was twofold greater (odds ratio [OR] 2.01; 95% confidence interval [CI] 1.14 to 3.53) and macroalbuminuria was threefold greater (OR 3.17; 95% CI 1.09 to 9.26) for Asians as compared with whites. Among those with hypertension, adjusted odds of microalbuminuria were greater for Hispanics (OR 3.82; 95% CI 1.16 to 12.57) than whites, whereas adjusted odds of macroalbuminuria were threefold greater for blacks (OR 3.32; 95% CI 1.26 to 8.76) than for whites. For most racial/ethnic minorities, hypertriglyceridemia was significantly associated with greater odds of micro- and macroalbuminuria. Among a large primary care population, racial/ethnic differences exist in the adjusted prevalence of microalbuminuria and macroalbuminuria depending on hypertension status. In this setting, racial/ethnic differences in early diabetic nephropathy were observed despite comparable access to diabetes care.

Endothelial Dysfunction and Mild Renal Insufficiency in Essential Hypertension

Background— Mild to moderate renal insufficiency in individuals with essential hypertension is currently considered the expression of a renal microvasculopathy characterized by preglomerular arteriolar involvement and tubulo-interstitial changes. Whether endothelial dysfunction plays a role in this alteration is still undefined.

Methods and Results— We investigated the relationship between endothelial function (hemodynamic response to acetylcholine [ACh] in the forearm) and renal function in 500 patients with uncomplicated, never-treated, essential hypertension and serum creatinine within the normal range (ie, ≤1.5 mg/dL). Serum creatinine, creatinine clearance, and estimated glomerular filtration rate (GFR, by the Modification of Diet in Renal Disease formula) were related to the forearm blood flow response to ACh (all P ≤0.003), and these relationships held true in multiple regression analyses that included age, gender, systolic pressure, serum cholesterol and glucose, smoking, and body mass index. Accordingly, on multiple logistic regression analysis, the risk of moderate renal dysfunction (ie, an estimated GFR <60 mL · min −1 · 1.73 m −2 ) was 64% lower (OR 0.36, 95% CI 0.18 to 0.70) in patients in the third ACh tertile (ie, those showing the higher vasodilatory response) than in those in the first tertile (ie, showing the lower response). C-reactive protein was related directly to serum creatinine and inversely to GFR and vasodilatory response to ACh, which suggests that endothelial dysfunction is a possible mechanism linking inflammation and impaired renal function in essential hypertension.

Conclusions— An impaired vasodilatory response to ACh appears to be associated with renal function loss in patients with essential hypertension. This association suggests that systemic endothelial dysfunction is involved in mild to moderate renal insufficiency in patients with uncomplicated essential hypertension.