Evaluation of risk for incident hypertension using glomerular filtration rate in the normotensive general population

Close relationship between electrocardiogram QRS duration and the risk of developing hypertension

Electrocardiogram QRS duration is associated with cardiovascular events and all-cause death. The present study was conducted to investigate the hypothesis that the QRS duration predicts the future development of hypertension in the Japanese general population with normal blood pressure. Overall, 13,382 individuals without bundle branch block, Wolff-Parkinson-White syndrome, complete atrioventricular block, pacemaker implantation, or old myocardial infarction on electrocardiogram were enrolled. The cross-sectional analysis indicated that the QRS duration was longer in hypertensive than in normotensive participants. After excluding the participants with hypertension, the remaining 9293 participants with normal blood pressure (male = 5425, 50.2 ± 11.7 years) were followed up for the median of 4 years with an endpoint of hypertension development. During the follow-up period, 1953 participants developed hypertension (50.6 per 1000 person-year). Kaplan-Meier analysis revealed that the incidence of hypertension increased across the quartiles of participants based on QRS duration at baseline as 39.0, 48.6, 53.7, and 62.4 per 1000 person-years in the first, second, third, and fourth quartiles, respectively. Univariate analysis confirmed a significant impact of QRS duration on the development of hypertension. In the multivariate Cox hazard regression analysis adjusted for possible confounding variables, QRS duration was an independent predictor of the development of hypertension. These results suggest the close association between electrocardiogram QRS duration and the future development of hypertension in the Japanese general population. Moreover, alterations in the intraventricular conduction may precede clinically apparent hypertension.

Significance of blood pressure variability in normotensive individuals as a risk factor of developing hypertension

PURPOSE

Visit-to-visit blood pressure variability is a strong predictor of the incidence of cardiovascular events and target organ damage due to hypertension. The present study investigated whether year-to-year blood pressure variability predicts the risk of hypertension in the Japanese general population.

MATERIALS AND METHODS

This study analysed 2806 normotensive individuals who participated in our physical check-up program for five years in a row from 2008 to 2013. The average, standard deviation, coefficient of variation, average real variability, and highest value of systolic blood pressure in the five consecutive visits were determined and used as baseline data. The participants were followed up for the next 6 years with the development of 'high blood pressure', an average blood pressure level of ≥140/90 mmHg or the use of antihypertensive medications, as the endpoint.

RESULT

During follow-up, 'high blood pressure' developed in 389 participants (13.9%, 29.5 per 1 000 person-years). The incidence increased across the quartiles of standard deviation and average real variability, while the average and highest systolic blood pressure had the most prominent impact on the development of 'high blood pressure'. Multivariate logistic regression analysis adjusted for possible risk factors indicated that the average, standard deviation, average real variability, and highest blood pressure, but not the coefficient of variation of systolic blood pressure, were significant predictors of 'high blood pressure'.

CONCLUSION

Increased year-to-year blood pressure variability predicts the risk of hypertension in the general normotensive population. The highest blood pressure in the preceding years may also be a strong predictor of the risk of hypertension.

A metabolomic index based on lipoprotein subfractions and branched chain amino acids is associated with incident hypertension

OBJECTIVE

The present study aims to evaluate the performance of the Diabetes Risk Index (DRI), a metabolomic index based on lipoprotein particles and branched chain amino acids, on the incidence of newly developed hypertension in a large community dwelling cohort.

METHODS

The DRI was calculated by combining 6 lipoprotein parameters [sizes of very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL) and high-density lipoprotein (HDL), concentrations of large VLDL, small LDL, and large HDL particles], and the concentrations of valine and leucine. DRI scores were estimated in 4169 participants from the PREVEND prospective cohort. Cox proportional hazards regression was used to evaluate the association of DRI scores with incident hypertension.

RESULTS

During a median follow-up of 8.6 years, 924 new hypertension cases were ascertained. In analyses adjusted for age and sex, there was a significant association between DRI and incident hypertension with a hazard ratio (HR) per 1 SD increase of 1.45 (95% CI 1.36,1.54; p < 0.001). After additional adjustment for traditional risk factors, the HR remained significant (HR_adj 1.21, 95% CI 1.10, 1.33, p <0.001). Likewise, subjects in the top quartile of DRI presented with a higher risk of hypertension (HR_adj 1.64, 95% CI 1.28, 2.10, p <0.001). Furthermore, the net reclassification improvement assessment improved after the addition of DRI to a traditional risk model (p <0.001), allowing proper reclassification of 34% of the participants.

CONCLUSION

Higher DRI scores were associated with an increased risk of incident hypertension. Such association was independent of traditional clinical risk factors for hypertension.

Clustering of risk factors and the risk of new-onset hypertension defined by the 2017 ACC/AHA Hypertension Guideline

The 2017 American College of Cardiology (ACC)/American Heart Association (AHA) lowered the diagnostic criteria for hypertension. We aimed to explore whether clustering of multiple risk factors are associated with the risk of new-onset hypertension defined by the 2017 ACC/AHA Hypertension Guideline. Subjects who attended ≥2 annual health examinations without baseline hypertension and cardiovascular disease were included. Hypertension was defined according to the 2017 ACC/AHA Hypertension Guideline. Seven predefined risk factors, including age, resting heart rate, overweight or obesity, dyslipidemia, hyperuricemia, impaired glucose regulation, and a poor estimated glomerular filtration rate, were analyzed. A composite, individual-level, cumulative score incorporating these seven risk factors (no = 0 point; yes = 1 point; total range of 0-7 points) was calculated. The association between the cumulative score and the risk of hypertension was analyzed using a Cox regression model. A total of 4424 (21.6%) of 20,190 subjects included had new-onset hypertension during a follow-up duration of 3.6 years. Compared with subjects with 0 points, the adjusted hazard ratios (95% confidence intervals) for the development of hypertension for those with 1, 2, 3, and ≥4 points were 1.21 (1.07-1.38), 1.34 (1.19-1.52), 1.44 (1.26-1.63), and 1.64 (1.44-1.87), respectively (P < 0.001), after adjustment for sex and baseline blood pressure. Age, resting heart rate, overweight/obesity, dyslipidemia, hyperuricemia, impaired glucose regulation, and a poor estimated glomerular filtration rate are associated with an increased risk of future hypertension. When these factors are combined, there is an accumulated increase in risk.

Effects of Lactotripeptide Supplementation on Tele-Monitored Home Blood Pressure and on Vascular and Renal Function in Prehypertension ― Randomized, Double-Blind, Placebo-Controlled, Cross-Over Study ―

Background: This randomized, double-blind, placebo-controlled, cross-over study was conducted to examine the effects of lactotripeptide supplementation on 7-day mean tele-monitored home blood pressure (BP), and also on the markers of vascular function and renal damage in Japanese subjects with prehypertension.

Methods and Results: A total of 26 subjects with prehypertension were randomly allocated to receive the active product (lactotripeptide tablet) or a placebo tablet for 8 weeks each in a cross-over manner. Urinary liver-type fatty acid-binding protein-to-creatine ratio (UFABPCR) and vascular function were measured at the end of each intervention. Home systolic and diastolic BP at the end of the lactotripeptide supplementation period was significantly lower than that at the end of the placebo period (P<0.05). On mixed linear model analysis there was a significant difference in the change in home diastolic BP after intervention between the 2 interventions (P=0.04). UFABPCR was significantly lower at the end of the lactotripeptide intervention period than at the end of the placebo period (P<0.05).

Conclusions: The beneficial effect of lactotripeptide supplementation on 7-day mean tele-monitored home BP was confirmed in Japanese subjects with prehypertension. In addition, this intervention also seemed to have a protective effect against the progression of renal function decline.

Concentration of Branched-Chain Amino Acids Is a Strong Risk Marker for Incident Hypertension

The potential role of branched-chain amino acids (BCAAs) in the pathogenesis of cardiometabolic diseases is increasingly recognized, but the association of BCAAs with incident hypertension remains unknown. The aim of the present study was to explore the association of BCAAs with incident hypertension in a prospective population-based cohort study. We measured plasma concentrations of BCAAs by means of nuclear magnetic resonance spectroscopy in 4169 participants from the PREVEND (Prevention of Renal and Vascular End-stage Disease) study. We estimated the risk of incident hypertension using multivariable-adjusted Cox regression models. After a median follow-up of 8.6 years, incident hypertension was ascertained in 924 subjects. Cox regression analyses revealed a significant association between BCAAs and incident hypertension. The hazard ratio per one SD of BCAAs was 1.11 (95% CI, 1.02-1.20; P=0.01) after full adjustment for multiple clinical variables. Likewise, the fully adjusted association remained significant when evaluated as categorical variable (hazard ratio for upper quartile with lowest quartile as reference category, 1.36; 95% CI, 1.11-1.68; P=0.003). Furthermore, the net reclassification improvement assessment improved after addition of BCAAs to a traditional risk model (P<0.001). This prospective study revealed that high plasma concentrations of BCAAs are associated with an increased risk of newly developed hypertension. The association remained after adjusting for age, sex, body mass index, and lipid profile.

Salvia miltiorrhiza in Treating Cardiovascular Diseases: A Review on Its Pharmacological and Clinical Applications

Bioactive chemical constitutes from the root of Salvia miltiorrhiza classified in two major groups, viz., liposoluble tanshinones and water-soluble phenolics. Tanshinone IIA is a major lipid-soluble compound having promising health benefits. The in vivo and in vitro studies showed that the tanshinone IIA and salvianolate have a wide range of cardiovascular and other pharmacological effects, including antioxidative, anti-inflammatory, endothelial protective, myocardial protective, anticoagulation, vasodilation, and anti-atherosclerosis, as well as significantly help to reduce proliferation and migration of vascular smooth muscle cells. In addition, some of the clinical studies reported that the S. miltiorrhiza preparations in combination with Western medicine were more effective for treatment of various cardiovascular diseases including angina pectoris, myocardial infarction, hypertension, hyperlipidemia, and pulmonary heart diseases. In this review, we demonstrated the potential applications of S. miltiorrhiza, including pharmacological effects of salvianolate, tanshinone IIA, and its water-soluble derivative, like sodium tanshinone IIA sulfonate. Moreover, we also provided details about the clinical applications of S. miltiorrhiza preparations in controlling the cardiovascular diseases.

Involvement of Arterial Stiffness and Inflammation in Hyperuricemia-Related Development of Hypertension

This study analyzed repeated measurement data to clarify the longitudinal associations between hyperuricemia and the risk factors for the development of hypertension (ie, increased arterial stiffness, renal dysfunction, and inflammation), and then examined whether these risk factors show longitudinal associations with the development of hypertension. In 3274 Japanese men without hypertension, the brachial-ankle pulse wave velocity, blood pressure, estimated glomerular filtration rate, and serum uric acid and CRP (C-reactive protein) levels were measured annually over an 8-year period. Of these, 474 subjects developed hypertension by the end of the study period. Mixed model linear regression analysis revealed a significant longitudinal association of hyperuricemia with increase of the brachial-ankle pulse wave velocity (estimate=5.50, P=0.04), decrease of the estimated glomerular filtration rate (estimate=-2.02, P<0.01), and elevation of the CRP (estimate=0.08×10^-1, P=0.02). Hyperuricemia at the study baseline was associated with a significant odds ratio for the development of hypertension by the end of the study period. After adjustments for covariates, the brachial-ankle pulse wave velocity (estimate=0.51×10^-2, P<0.01) and CRP (estimate=1.91, P=0.03), but not estimated glomerular filtration rate, were found to show independent longitudinal associations with the new onset of hypertension. In Japanese men without hypertension, hyperuricemia may have a longitudinal association with the development of hypertension, and increased arterials stiffness and inflammation may be involved in the risk of development of hypertension associated with hyperuricemia.

Combined impact of risk factors on the subsequent development of hypertension

OBJECTIVES

This study aimed to develop a cumulative score composed of seven risk factors: age, resting heart rate, overweight or obesity, dyslipidemia, hyperuricemia, impaired glucose regulation, and impaired estimated glomerular filtration rate (eGFR), to evaluate the risk of new-onset hypertension.

METHODS

We retrospectively conducted a cohort study in 23 665 participants free from hypertension at baseline, who attended at least two annual health examinations between 2011 and 2016. We defined hypertension as SBP of 140 mmHg or less and/or DBP of at least 90 mmHg, according to the 2010 Chinese guidelines for the management of hypertension. We computed a composite, individual-level cumulative score incorporating all seven risk factors (no = 0 point; yes = 1 point; total range 0-7 points). Cox regression was used to analyze the association between cumulative score and risk of hypertension.

RESULTS

A total of 2305 participants developed hypertension during a median follow-up period of 3.6 years. Compared with participants with 0 points, the adjusted hazard ratios (95% confidence intervals) for the development of hypertension for those with 2, 3, and at least 4 points were 1.61 (1.29-2.02), 2.05 (1.64-2.57) and 2.77 (2.22-3.46), respectively (P trend < 0.001). This association was present after adjustment for sex and baseline blood pressure.

CONCLUSION

Age, resting heart rate, overweight or obesity, dyslipidemia, hyperuricemia, impaired glucose regulation, and impaired eGFR were associated with significant risk of new-onset hypertension and when combined there was an accumulation of risk.

Carotid intima-media thickness is a novel predictor of new onset of hypertension in normotensive subjects

Increased carotid intima-media thickness (IMT) in individuals without hypertension might indicate other factors promoting the atherosclerotic process that are often simultaneously clustered in individuals. The present study tested the hypothesis that carotid IMT predicts new onset of hypertension in the normotensive subjects.A total of 867 participants were enrolled from our yearly physical checkup program and their carotid IMT was measured. After a baseline examination, the subjects were followed up for a median of 1091 days with the endpoint being the development of hypertension.At baseline, the carotid IMT value was 0.75 ± 0.16 mm. Hypertension developed in 184 subjects during the follow-up (76.9/1000 person-years). The incidence of hypertension was increased across the tertiles of the carotid IMT value (39.6, 70.0, and 134.5/1000 person-years in the first, second, and third tertiles, respectively, P < .001 by log-rank test). Multivariate Cox-hazard analysis after adjustment identified carotid IMT, taken as a continuous variable, as a significant predictor of new-onset hypertension (hazard ratio = 7.08, 95% confidence interval = 3.06-15.39). Furthermore, multivariate linear regression analyses indicated a significant correlation between the carotid IMT at baseline and yearly increases in systolic blood pressure during the follow-up period (β = 0.189, P < .001).Carotid IMT is an independent predictor of hypertension onset in normotensive subjects. The findings also suggested a close association between increased carotid IMT and blood pressure.

The Contribution of Inflammation to the Development of Hypertension Mediated by Increased Arterial Stiffness

BACKGROUND

The mechanisms underlying the possible contribution of chronic inflammation to the development of hypertension remain unclear. We examined the longitudinal association of inflammation with the progression of vascular and/or renal abnormalities in the development of hypertension.

METHODS AND RESULTS

In 3274 middle-aged Japanese men without hypertension at the study baseline, brachial-ankle pulse wave velocity, blood pressure, estimated glomerular filtration rate, and serum CRP (C reactive protein) levels were measured annually during a 9-year period. During this study period, 474 participants (14.5%) developed hypertension. Analysis of the repeated-measures data revealed that sustained elevation of serum CRP levels was associated with a longitudinal increase of the brachial-ankle pulse wave velocity. A linear mixed model analysis revealed that higher log-transformed serum CRP values (log CRP) at each measurement were associated with a higher annual increase of the brachial-ankle pulse wave velocity (estimate=32.553±11.635 cm/s per log CRP, P=0.018), and that higher values of the brachial-ankle pulse wave velocity at each measurement were associated with a higher annual elevation of blood pressure (estimate=0.025±0.002 mm Hg per log CRP, P<0.001).

CONCLUSIONS

In middle-aged Japanese men without hypertension at study baseline, long-term active inflammation appears to be associated with a longitudinal increase of arterial stiffness. In turn, this longitudinal increase of arterial stiffness appears to be associated with longitudinal elevation of blood pressure to the hypertensive range. Thus, systemic inflammation may play a role in the pathogenesis of hypertension by the progression of arterial stiffness.

Association of Kidney Function and Early Kidney Injury With Incident Hypertension in HIV-Infected Women

Subclinical kidney disease is associated with developing hypertension in the general population, but data are lacking among HIV-infected people. We examined associations of kidney function and injury with incident hypertension in 823 HIV-infected and 267 HIV-uninfected women in the Women's Interagency HIV Study, a multicenter, prospective cohort of HIV-infected and uninfected women in the United States. Baseline kidney biomarkers included estimated glomerular filtration rate using cystatin C, urine albumin-to-creatinine ratio, and 7 urine biomarkers of tubular injury: α-1-microglobulin, interleukin-18, kidney injury molecule-1, neutrophil gelatinase-associated lipocalin, liver fatty acid-binding protein, N-acetyl-β-d-glucosaminidase, and α1-acid-glycoprotein. We used multivariable Poisson regression to evaluate associations of kidney biomarkers with incident hypertension, defined as 2 consecutive visits of antihypertensive medication use. During a median follow-up of 9.6 years, 288 HIV-infected women (35%) developed hypertension. Among the HIV-infected women, higher urine albumin-to-creatinine ratio was independently associated with incident hypertension (relative risk =1.13 per urine albumin-to-creatinine ratio doubling, 95% confidence interval, 1.07-1.20), as was lower estimated glomerular filtration rate (relative risk =1.10 per 10 mL/min/1.73 m² lower estimated glomerular filtration rate; 95% confidence interval, 1.04-1.17). No tubular injury and dysfunction biomarkers were independently associated with incident hypertension in HIV-infected women. In contrast, among the HIV-uninfected women, urine albumin-to-creatinine ratio was not associated with incident hypertension, whereas higher urine interleukin-18, α1-acid-glycoprotein, and N-acetyl-β-d-glucosaminidase levels were significantly associated with incident hypertension. These findings suggest that early glomerular injury and kidney dysfunction may be involved in the pathogenesis of hypertension in HIV-infected people. The associations of tubular markers with hypertension in HIV-uninfected women should be validated in other studies.

Long-Term Exposure to Ambient Fine Particulate Matter and Renal Function in Older Men: The Veterans Administration Normative Aging Study

BACKGROUND

It is unknown if ambient fine particulate matter (PM2.5) is associated with lower renal function, a cardiovascular risk factor.

OBJECTIVE

We investigated whether long-term PM2.5 exposure was associated with estimated glomerular filtration rate (eGFR) in a cohort of older men living in the Boston Metropolitan area.

METHODS

This longitudinal analysis included 669 participants from the Veterans Administration Normative Aging Study with up to four visits between 2000 and 2011 (n = 1,715 visits). Serum creatinine was measured at each visit, and eGFR was calculated according to the Chronic Kidney Disease Epidemiology Collaboration equation. One-year exposure to PM2.5 prior to each visit was assessed using a validated spatiotemporal model that utilized satellite remote-sensing aerosol optical depth data. eGFR was modeled in a time-varying linear mixed-effects regression model as a continuous function of 1-year PM2.5, adjusting for important covariates.

RESULTS

One-year PM2.5 exposure was associated with lower eGFRs; a 2.1-μg/m3 interquartile range higher 1-year PM2.5 was associated with a 1.87 mL/min/1.73 m2 lower eGFR [95% confidence interval (CI): -2.99, -0.76]. A 2.1 μg/m3-higher 1-year PM2.5 was also associated with an additional annual decrease in eGFR of 0.60 mL/min/1.73 m2 per year (95% CI: -0.79, -0.40).

CONCLUSIONS

In this longitudinal sample of older men, the findings supported the hypothesis that long-term PM2.5 exposure negatively affects renal function and increases renal function decline.

CITATION

Mehta AJ, Zanobetti A, Bind MC, Kloog I, Koutrakis P, Sparrow D, Vokonas PS, Schwartz JD. 2016. Long-term exposure to ambient fine particulate matter and renal function in older men: the VA Normative Aging Study. Environ Health Perspect 124:1353-1360; http://dx.doi.org/10.1289/ehp.1510269.

Use of Electrocardiography to Predict Future Development of Hypertension in the General Population

Cardiac muscle responds to increased afterload by developing hypertrophy. During the early stages of hypertension, the heart can be transiently, but frequently, exposed to increased afterload. This study was designed to test the hypothesis that left ventricular hypertrophy (LVH) assessed by electrocardiography (ECG) can be used to predict future development of hypertension.Sokolow-Lyon voltage and Cornell product were calculated using ECG in 5770 normotensive participants who visited our hospital for a physical checkup (age 52.7 ± 11.3 years). LVH was defined as a Sokolow-Lyon voltage of >3.8 mV or a Cornell product of >2440 mm × ms. After baseline examination, participants were followed up with the endpoint being the development of hypertension.During the median follow-up period of 1089 days (15,789 person-years), hypertension developed in 1029 participants (65.2/1000 person-years). A Kaplan-Meier analysis demonstrated a significantly higher incidence of hypertension in participants with LVH than in those without LVH as assessed by Sokolow-Lyon voltage or Cornell product (P < 0.0001 for both). The hazard ratios for incident hypertension in participants with LVH defined by Sokolow-Lyon voltage and Cornell product were 1.49 (95% confidence interval [CI] 1.16-1.90, P < 0.01) and 1.34 (95% CI 1.09-1.65, P < 0.01), respectively, after adjustment for possible risk factors. Furthermore, in multivariable Cox hazard analysis, where Sokolow-Lyon voltage and Cornell product were taken as continuous variables, both indices were independent predictors of future hypertension (P < 0.0001).Both Sokolow-Lyon voltage and Cornell product are novel predictors of future development of hypertension in the general population.

Urinary albumin as a marker of future blood pressure and hypertension in the general population

We investigated whether urinary albumin could predict the development of hypertension and future increases in blood pressure in the normotensive general population.Normotensive subjects who visited our hospital for a physical checkup (n = 6205, men 61.8%, 53.4 ± 11.4 years old) were enrolled in this study. Urine samples were collected for the measurement of albumin concentration, expressed as the ratio of urinary albumin to creatinine concentrations (UACR [mg/g Cr]). After the baseline examination, subjects were followed up for a median of 1089 days with the endpoint being the development of hypertension.Urinary albumin was in the normal range (UACR <30 mg/g Cr) in most subjects (97.5%). During the follow-up, hypertension developed in 1184 subjects (19.1%, 69.5 per 1000 person-years), with more men than women affected. The incidence of hypertension was increased across the quartiles of UACR by Kaplan-Meier analysis (log-rank, P < 0.0001) and the hazard ratio (lowest quartile [median UACR 1.14 mg/g Cr] as reference) was 1.53 (95% confidence intervals 1.30-1.80) in the highest quartile (median UACR 8.87 mg/g Cr). Multivariate Cox hazard analysis in which UACR was taken as a continuous variable identified UACR as a significant predictor of hypertension (hazard ratio 1.37, 95% CI 1.20-1.56). UACR was also an independent predictor of future increases in systolic blood pressure (P < 0.01).Urinary albumin is an independent predictor of hypertension and increases in blood pressure in the general population even in the normal range below the threshold defined for microalbuminuria.

Association of kidney function and albuminuria with prevalent and incident hypertension: the Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND

Decreased kidney function and kidney damage may predate hypertension, but only a few studies have investigated both types of markers simultaneously, and these studies have obtained conflicting results.

STUDY DESIGN

Cross-sectional for prevalent and prospective observational study for incident hypertension.

SETTING & PARTICIPANTS

9,593 participants from the ARIC (Atherosclerosis Risk in Communities) Study, aged 53-75 years in 1996-1998.

PREDICTORS

Several markers of kidney function (estimated glomerular filtration rate using serum creatinine and/or cystatin C and 2 novel markers [β-trace protein and β2-microglobulin]) and 1 marker of kidney damage (urinary albumin-creatinine ratio [ACR]). Every kidney marker was categorized by its quintiles (top quintile as a reference for estimated glomerular filtration rates and bottom quintile for the rest).

OUTCOMES

Prevalent and incident hypertension.

MEASUREMENTS

Prevalence ratios and HRs of hypertension based on modified Poisson regression and Cox proportional hazards models, respectively.

RESULTS

There were 4,378 participants (45.6%) with prevalent hypertension at baseline and 2,175 incident hypertension cases during a median follow-up of 9.8 years. Although all 5 kidney function markers were associated significantly with prevalent hypertension, prevalent hypertension was associated most notably with higher ACR (adjusted prevalence ratio, 1.60 [95% CI, 1.50-1.71] for the highest vs lowest ACR quintile). Similarly, ACR was associated consistently with incident hypertension in all models tested (adjusted HR, 1.28 [95% CI, 1.10-1.49] for top quintile), while kidney function markers demonstrated significant associations in some, but not all, models. Even mildly increased ACR (9.14-14.0mg/g) was associated significantly with incident hypertension.

LIMITATIONS

Self-reported use of antihypertensive medication for defining incident hypertension, single assessment of kidney markers, and relatively narrow age range.

CONCLUSIONS

Although all kidney markers were associated with prevalent hypertension, only elevated albuminuria was associated consistently with incident hypertension, suggesting that kidney damage is related more closely to hypertension than moderate reduction in overall kidney function.

Serum cystatin C, creatinine-based estimated glomerular filtration rate, and the risk of incident hypertension in middle-aged men

BACKGROUND

The aim of this study was to examine the predictive value of serum cystatin C (CysC) and that of creatinine-based estimated glomerular filtration rate (eGFRCreat) for the risk of incident hypertension in a middle-aged male population.

METHODS

Serum CysC levels were measured in 904 nonhypertensive, Japanese male subjects (mean age = 44±6 years) who received an annual general health examination in a company. Serum creatinine levels were simultaneously measured, and eGFRCreat was calculated. Subjects were followed-up for a maximum period of 4 years, and annual blood pressure measurements were recorded.

RESULTS

During the follow-up period, 124 subjects developed hypertension, defined as systolic/diastolic blood pressure ≥140/90 mmHg or use of antihypertensive medications. In the Kaplan-Meier analysis, both the third quintile of CysC and that of eGFRCreat showed the lowest 4-year cumulative incident rate of hypertension. The multiadjusted hazard ratio for incident hypertension was significantly increased in the highest quintile of CysC compared with the third quintile (2.60; 95% confidence interval (CI) = 1.41-4.77; P = 0.002), as well as compared with the lowest 4 quintiles combined (1.89; 95% CI = 1.26-2.84; P = 0.002). However, eGFRCreat did not show significant hazard ratios for incident hypertension in any of the adjusted models.

CONCLUSIONS

Elevated serum CysC levels could predict the risk of incident hypertension in this study population with a maximum follow-up period of 4 years. In contrast, eGFRCreat did not show predictive value for the risk of incident hypertension.

Associations of proteinuria and the estimated glomerular filtration rate with incident hypertension in young to middle-aged Japanese males

OBJECTIVE

To investigate the independent associations of proteinuria and the estimated glomerular filtration rate (eGFR) with incident hypertension.

METHODS

We investigated 29,181 Japanese males 18-59years old without hypertension in 2000 and examined whether proteinuria and the eGFR predicted incident hypertension independently over 10years. Incident hypertension was defined as a newly detected blood pressure of ≥140/90mmHg and/or the initiation of antihypertensive drugs. Proteinuria and the eGFR were categorized as dipstick negative (reference), trace or ≥1+ and ≥60 (reference), 50-59.9 or <50ml/min/1.73m(2), respectively. Cox proportional hazards models were used to estimate the hazard ratios (HRs) of incident hypertension.

RESULTS

At baseline, 236 (0.8%) and 477 (1.6%) participants had trace and ≥1+ dipstick proteinuria, while 1416 (4.9%) and 129 (0.4%) participants had an eGFR of 50-59.9 and <50ml/min/1.73m(2), respectively. The adjusted HRs were significant for proteinuria ≥1+ (HRs 1.20, 95% CI: 1.06-1.35) and an eGFR of <50ml/min/1.73m(2) (1.29, 1.03-1.61). When two non-referent categories were combined (dipstick≥trace vs. negative and eGFR<60 vs. ≥60ml/min/1.73m(2)), the association was more significant for proteinuria (1.15, 1.04-1.27) than for eGFR (0.99, 0.92-1.07).

CONCLUSIONS

Proteinuria and a reduced eGFR are independently associated with future hypertension in young to middle-aged Japanese males.

Uric acid levels predict future blood pressure and new onset hypertension in the general Japanese population

We tested the hypothesis that uric acid levels predict new-onset hypertension in the Japanese general population. Normotensive individuals who visited our hospital for a yearly health checkup (n=8157, men=61.0% and age=50.7±12.2 years) were enrolled in the present study. After baseline evaluation, participants were followed up for a median of 48.3 months (range 4.9-101.0 months), with the endpoint being the development of hypertension, defined as systolic blood pressure (BP) > or = 140 mm Hg, diastolic BP > or = 90 mm Hg or the use of antihypertensive medication. The impact of uric acid and other cardiovascular risk factors at baseline on future BP and development of hypertension was assessed. During follow-up, 19.0% of women (n=605) and 29.5% of men (n=1469) participants developed hypertension. Incident hypertension was increased across the quartiles for baseline uric acid levels (P<0.0001), and multivariate Cox proportional hazards analysis revealed a significant and independent association between the uric acid level and the onset of hypertension in both men and women participants (P<0.05). Furthermore, uric acid was independently and positively correlated with future BP (P<0.05). Thus, uric acid is an independent predictor of new-onset hypertension in both women and men.