Blood pressure, albuminuria and renal dysfunction: the 'chicken or egg' dilemma

Joint Association of Albuminuria and Left Ventricular Hypertrophy With Incident Heart Failure in Adults at High Risk With Hypertension: A Systolic Blood Pressure Intervention Trial Substudy

Albuminuria and left ventricular hypertrophy (LVH) are independent predictors of heart failure (HF); however, to the best of our knowledge, their combined effect on the risk of HF has not yet been explored. Therefore, we examined the joint associations of albuminuria and electrocardiographic-LVH with incident acute decompensated HF (ADHF), and whether albuminuria/LVH combinations modified the effects of blood pressure control strategy in reducing the risk of ADHF. A total of 8,511 participants from the Systolic Blood Pressure Intervention Trial (SPRINT) were included. Electrocardiographic-LVH was present if any of the following criteria were present: Cornell voltage, Cornell voltage product, or Sokolow-Lyon. Albuminuria was defined as urine albumin/creatinine ratio ≥30 mg/g. ADHF was defined as hospitalization or emergency department visit for ADHF. Cox proportional hazard models were used to examine the association of neither LVH nor albuminuria (reference), either LVH or albuminuria, and both (LVH + albuminuria) with incident ADHF. Over a median follow-up of 3.2 years, 182 cases of ADHF occurred. In adjusted models, concomitant albuminuria and LVH were associated with greater risk of ADHF than either albuminuria or LVH in isolation (hazard ratio [95% confidence interval]: 4.95 [3.22 to 7.62], 2.04 [1.39 to 3.00], and 1.47 [0.93 to 2.32], respectively, additive interaction p = 0.01). The effect of intensive blood pressure in reducing ADHF was attenuated in participants with coexisting albuminuria and LVH without any interaction between treatment group assignment and albuminuria/LVH categories (interaction p = 0.26). In conclusion, albuminuria and LVH are additive predictors of ADHF. The effect of intensive blood pressure control in reducing ADHF risk did not vary significantly across albuminuria/LVH combinations.

Joint Association of Albuminuria and Left Ventricular Hypertrophy with Incident Heart Failure in High-Risk Adults with Hypertension: a SPRINT substudy

Background

Albuminuria and left ventricular hypertrophy (LVH) are independent predictors of heart failure (HF), however their combined effect on risk of HF has not been explored previously.

Objectives

To examine the joint associations of albuminuria and electrocardiographic (ECG) LVH with incident acute decompensated HF (ADHF), and whether albuminuria/LVH combinations modified the effects of blood pressure control strategy in reducing the risk of ADHF.

Methods

8,511 participants from the SPRINT (Systolic Blood Pressure Intervention Trial) were included. ECG-LVH was present if any of the following criteria: Cornell voltage, Cornell voltage product, or Sokolow Lyon were present. Albuminuria was defined as urine albumin-creatinine ratio (UACR) ≥30 mg/g. ADHF was defined as hospitalization or emergency visit for ADHF. Cox proportional hazard models were used to examine the association of neither LVH, nor albuminuria (reference), either LVH or albuminuria, and both (LVH + albuminuria) with incident ADHF.

Results

Over a median follow-up of 3.2 years, 182 cases of ADHF occurred. In adjusted models, concomitant albuminuria and LVH were associated with higher risk of ADHF than either albuminuria or LVH in isolation (HR (95% CI): 4.95 (3.22-7.62), 2.04 (1.39-3.00), and 1.47 (0.93-2.32), respectively (additive interaction p=0.01). The effect of intensive blood pressure in decreasing ADHF attenuated among participants with co-existing albuminuria and LVH without any interaction between treatment group assignment and albuminuria/LVH categories (interaction p-value= 0.26).

Conclusions

Albuminuria and LVH are additive predictors of ADHF. The effect of intensive blood pressure control in decreasing ADHF risk did not vary significantly across albuminuria/LVH combinations.

Sex differences in impact of cumulative systolic blood pressure from childhood to adulthood on albuminuria in midlife: a 30-year prospective cohort study

BACKGROUND AND OBJECTIVES

Albuminuria is recognized as being a predictor of cardiovascular and renal disease. We aimed to identify the impact of the long-term burden and trends of systolic blood pressure on albuminuria in midlife, as well as to explore sex differences concerning this relationship.

METHODS

This longitudinal study consisted of 1,683 adults who had been examined 4 or more times for blood pressure starting in childhood, with a follow-up time period of 30 years. The cumulative effect and longitudinal trend of blood pressure were identified by using the area under the curve (AUC) of individual systolic blood pressure measurement with a growth curve random effects model.

RESULTS

Over 30 years of follow-up, 190 people developed albuminuria, including 53.2% males and 46.8% females (aged 43.39 ± 3.13 years in the latest follow-up). The urine albumin-to-creatinine ratio (uACR) values increased as the total and incremental AUC values increased. Additionally, women had a higher albuminuria incidence in the higher SBP AUC groups than men do (13.3% for men vs. 33.7% for women). Logistic regression showed that the ORs of albuminuria for males and females in the high total AUC group were 1.34 (0.70-2.60) and 2.94 (1.50-5.74), respectively. Similar associations were found in the incremental AUC groups.

CONCLUSIONS

Higher cumulative SBP was correlated with higher uACR levels and a risk of albuminuria in middle age, especially in women. The identification and control of cumulative SBP levels from an early age may assist in reducing the incidences of renal and cardiovascular disease for individuals in later life.

Association of the Atherogenic Index of Plasma with C-Reactive Protein and Urinary Albumin Excretion in a Normotensive Nondiabetic Population

Background: The atherogenic index of plasma (AIP) is an indicator of atherogenic dyslipidemia and is significantly associated with the development of atherosclerotic cardiovascular disease. Previous studies showing the association of AIP with C-reactive protein (CRP) and microalbuminuria included hypertensive and diabetic patients. We aimed to determine the association of AIP with CRP and albuminuria in a normotensive and nondiabetic population. Methods: The study was conducted retrospectively. Two hundred thirty-three individuals without hypertension, diabetes, cardiovascular disease, malignancy, systemic inflammatory disease, nephrological disease, and active infection were determined and included in the study. Urinary albumin excretion was calculated from the albumin-creatinine ratio in fresh spot urine [urinary albumin-creatinine ratio (UACR)]. AIP risk groups were compared in terms of clinical and laboratory findings, and the correlation between AIP and CRP and UACR was evaluated. Results: A total of 233 people, with a mean age of 45.4 years and 139 (69.7%) of whom were male, were included in the study. One hundred thirty-eight (59.2%) individuals were found to be in the low-risk group, 29 (12.5%) in the medium-risk group, and 66 (28.3%) in the high-risk group, according to the AIP value. CRP and UACR were not different between the AIP risk groups (P: 0.141 and 0.441, respectively). A mild correlation was found between AIP and CRP (r: 0.192; P: 0.003), but no correlation was found between AIP and UACR (r: 0.086; P: 0.193). The stepwise linear regression analysis with model adjusted for possible confounders and AIP revealed that only body mass index was a significant predictor of CRP (β: 0.308; P < 0.001), while only systolic blood pressure was a significant predictor of UACR (β: 0.19; P: 0.004), but AIP was not. Conclusions: AIP was not associated with CRP and UACR in normotensive and nondiabetic individuals. This finding suggests that the relationship found in previous studies is related to the presence of hypertension or diabetes rather than the AIP.

Identifying drug-related attributes to personalise antihypertensive agents: the outcome report of patients receiving metoprolol therapy

Background

Currently, numerous antihypertensive drugs from different pharmacological classes are available; however, blood pressure control is achieved in only less than a third of patients treated for hypertension. Moreover, providing optimal and personalised treatment for hypertension is challenging. Therefore, in this study, we propose a ‘drug-related attributes’ sensitive spectrum. This novel concept can assist clinicians in selecting an optimal antihypertensive drug and improve blood pressure control after examining the attributes of a patient.

Methods

We collected clinical data on attributes related to hypertension and its therapy of inpatients from West China Hospital who received metoprolol therapy and constructed the sensitive spectrum using data-visualisation tools.

Results

Our analysis revealed that haematocrit, haemoglobin, serum creatinine, serum cystatin C, serum urea, age, sex, systolic pressure, diastolic pressure, pulse pressure, and heart rate are metoprolol-related attributes.

Conclusion

Our study showed that all metoprolol-related attributes identified are reasonable and helpful in improving the personalisation of metoprolol therapy. The proposed drug-related attributes spectrum can help personalise antihypertensive medication. Moreover, data-visualisation tools can be effectively used to mine the drug-related attributes sensitive spectrum.

Proteinuria as a significant predictive factor for the progression of carotid artery atherosclerosis in non-albuminuric type 2 diabetes

AIMS

This study aimed to evaluate the clinical significance of urine protein to creatinine ratio (uPCR) in relation to the cardiovascular risk associated with carotid artery intima-media thickness (cIMT) progression in subjects with type 2 diabetes (T2D) and normoalbuminuria.

METHODS

In this retrospective longitudinal study on T2D, we recruited 927 participants with normoalbuminuria (urine albumin to creatinine ratio [uACR] < 30 mg/g) whose cIMT was measured at baseline and after at least 1 year, and whose initial uPCR and uACR data were available.

RESULTS

Higher initial uPCR was positively correlated with a greater increment in maximal cIMT (β = 0.074, p = 0.028), and this correlation was significant even after adjusting for multiple confounding factors (β = 0.074, p = 0.046). High baseline uPCR was an independent predictive factor for the increased risk of maximal cIMT progression in a simple logistic regression model (OR, 1.41; 95% CI, [1.08-1.86]; p = 0.013). Even after adjusting for several confounding variables, higher uPCR was significantly associated with a higher risk of cIMT progression (OR, 1.48; 95% CI, [1.08-2.03]; p = 0.014).

CONCLUSIONS

These results suggest that high uPCR may be a useful predictive marker for the progression of carotid artery atherosclerosis, even in subjects with T2D and without albuminuria.

Plasma C-Peptide and Risk of Developing Type 2 Diabetes in the General Population

C-peptide measurement may represent a better index of pancreatic β-cell function compared to insulin. While insulin is mainly cleared by liver, C-peptide is mainly metabolized by kidneys. The aim of our study was to evaluate the association between baseline plasma C-peptide level and the development of type 2 diabetes independent of glucose and insulin levels and to examine potential effect-modification by variables related to kidney function. We included 5176 subjects of the Prevention of Renal and Vascular End-Stage Disease study without type 2 diabetes at baseline. C-peptide was measured in plasma with an electrochemiluminescent immunoassay. Cox proportional hazards regression was used to evaluate the association between C-peptide level and type 2 diabetes development. Median C-peptide was 722 (566-935) pmol/L. During a median follow-up of 7.2 (6.0-7.7) years, 289 individuals developed type 2 diabetes. In multivariable-adjusted Cox regression models, we observed a significant positive association of C-peptide with the risk of type 2 diabetes independent of glucose and insulin levels (hazard ratio (HR): 2.35; 95% confidence interval (CI): 1.49-3.70). Moreover, we found significant effect modification by hypertension and albuminuria (p < 0.001 and p = 0.001 for interaction, respectively), with a stronger association in normotensive and normo-albuminuric subjects and absence of an association in subjects with hypertension or albuminuria. In this population-based cohort, elevated C-peptide levels are associated with an increased risk of type 2 diabetes independent of glucose, insulin levels, and clinical risk factors. Elevated C-peptide level was not independently associated with an increased risk of type 2 diabetes in individuals with hypertension or albuminuria.

Intravital imaging of the kidney in a rat model of salt-sensitive hypertension

Hypertension is one of the most prevalent diseases worldwide and a major risk factor for renal failure and cardiovascular disease. The role of albuminuria, a common feature of hypertension and robust predictor of cardiorenal disorders, remains incompletely understood. The goal of this study was to investigate the mechanisms leading to albuminuria in the kidney of a rat model of hypertension, the Dahl salt-sensitive (SS) rat. To determine the relative contributions of the glomerulus and proximal tubule (PT) to albuminuria, we applied intravital two-photon-based imaging to investigate the complex renal physiological changes that occur during salt-induced hypertension. Following a high-salt diet, SS rats exhibited elevated blood pressure, increased glomerular sieving of albumin (GSC_alb = 0.0686), relative permeability to albumin (+Δ16%), and impaired volume hemodynamics (-Δ14%). Serum albumin but not serum globulins or creatinine concentration was decreased (-0.54 g/dl), which was concomitant with increased filtration of albumin (3.7 vs. 0.8 g/day normal diet). Pathologically, hypertensive animals had significant tubular damage, as indicated by increased prevalence of granular casts, expansion and necrosis of PT epithelial cells (+Δ2.20 score/image), progressive augmentation of red blood cell velocity (+Δ269 µm/s) and micro vessel diameter (+Δ4.3 µm), and increased vascular injury (+Δ0.61 leakage/image). Therefore, development of salt-induced hypertension can be triggered by fast and progressive pathogenic remodeling of PT epithelia, which can be associated with changes in albumin handling. Collectively, these results indicate that both the glomerulus and the PT contribute to albuminuria, and dual treatment of glomerular filtration and albumin reabsorption may represent an effective treatment of salt-sensitive hypertension.

Subclinical atherosclerosis in young Thai adults with juvenile-onset systemic lupus erythematosus

Background

Cardiovascular disease (CVD) is a leading cause of morbidity and mortality in adult patients with systemic lupus erythematosus (SLE). Increased risk of CVD and atherosclerosis has been demonstrated in children with SLE. However, evidence of atherosclerosis in adults with juvenile-onset SLE is limited and their additional CVD risk factors unclear.

Objectives

To investigate the presence of subclinical atherosclerosis in young Thai adults with juvenile-onset SLE, and evaluate atherosclerotic risk factors.

Methods

We recruited a cohort of patients aged 18-40 years who had been diagnosed SLE before the age of 18 years for this observational study. Patients with chronic kidney disease stage IV or V, alcoholism, chronic liver disease, or life threatening illness were excluded. Common carotid intima-media thickness (CCIMT) was measured. Clinical and laboratory parameters, treatment, and SLE-related factors, which could be risk factors for atherosclerosis and classic risk factors were obtained.

Results

We enrolled 29 patients (24 female). Their mean age was 25.1 years and mean disease duration 11.3 years. The age of participants, persistent proteinuria and use of cyclosporin correlated with increased CCIMT by multivariable analysis (P = 0.02, 0.02, and 0.03, respectively). These patients had significantly abnormal CCIMT when compared with a healthy population (mean 690 (SD 150) μm versus mean 447 (SD 76) μm, respectively; P < 0.001).

Conclusions

Subclinical atherosclerosis, identified by abnormal CCIMT, appears in young adults with juvenile-onset SLE. The CCIMT abnormality progresses with increasing age, and persistent proteinuria and use of cyclosporin appears to increase the risk for atherosclerosis.

Microalbuminuria in primary hypertension: a guide to optimal patient management?

Accurate assessment of the global risk profile is considered a prerequisite for the optimal management of hypertensive patients. In particular, the evaluation of subclinical organ damage, namely left ventricular hypertrophy, peripheral atherosclerosis and renal function, plays a key role in optimizing therapeutic targets and strategy in individual patients. Urine albumin excretion is a low-cost, easy-to-use test and a powerful predictor of cardiovascular diseases. The search for albuminuria has, therefore, become routine in the evaluation of hypertensive patients. Moreover, albuminuria has been shown to be associated with early signs of extra-renal organ damage such as left ventricular hypertrophy, and carotid atherosclerosis. Under effective antihypertensive treatment, changes in subclinical organ damage over time, especially regression of left ventricular hypertrophy, are paralleled by modification of risk status and may serve as intermediate endpoints for treatment. More recently, changes in albuminuria have also been proposed to reflect changes in the risk of cardiovascular events. If this is confirmed by large well-designed studies, microalbuminuria may not simply be regarded as a risk predictor but become itself an independent target for treatment.

Comparison of Acarbose and Metformin on Albumin Excretion in Patients With Newly Diagnosed Type 2 Diabetes: A Randomized Controlled Trial

Increased urinary albumin excretion in diabetes not only signals nephropathy but also serves as a risk marker for cardiovascular disease. The data of MARCH (Metformin and AcaRbose in Chinese as the initial Hypoglycaemic treatment) trial demonstrated that acarbose and metformin were similarly efficacious at lowering blood glucose and blood pressure, as well as improving insulin sensitivity in Chinese patients newly diagnosed with type 2 diabetes mellitus. The purpose of this study was to identify the effects of acarbose and metformin therapy on albumin excretion in MARCH study.Baseline urine albumin/creatinine ratio (ACR) of 762 newly diagnosed, drug-naïve patients with type 2 diabetes mellitus was measured. Included patients were randomized to receive either acarbose or metformin and followed for 48 weeks. In addition to change in ACR, the estimated glomerular filtration rates (eGFR) and frequency of metabolic syndrome (MetS) were also assessed.Elevated ACR levels (≥30 mg/g) were present at baseline in 21.9% of all participants. A significant decline in urine ACR was observed in both the acarbose and metformin groups at week 24 and 48 (all P < 0.001). The proportion of patients with elevated ACRs was also reduced in both treatment groups at week 24 and 48 compared with baseline values (all P < 0.05). The change in urine ACR at week 48 was significantly greater in patients prescribed acarbose than in those prescribed metformin (P = 0.01). Both acarbose and metformin significantly decreased the frequency of MetS at week 24 and 48 (both P < 0.05). Neither treatment affected eGFR.In sum, both acarbose and metformin decreased urine ACR levels and reduced the frequency of elevated ACR and MetS in Chinese patients with newly diagnosed type 2 diabetes mellitus without affecting eGFR. After 48 weeks' intervention, acarbose therapy resulted in a greater reduction in urine ACR compared with metformin.

Kidney Function Decline and Apparent Treatment-Resistant Hypertension in the Elderly

BACKGROUND

Cross-sectional studies show a strong association between chronic kidney disease and apparent treatment-resistant hypertension, but the longitudinal association of the rate of kidney function decline with the risk of resistant hypertension is unknown.

METHODS

The population-based Three-City included 8,695 participants older than 65 years, 4265 of them treated for hypertension. We estimated the odds ratios (OR) of new-onset apparent treatment-resistant hypertension, defined as blood pressure ≥ 140/90 mmHg despite use of 3 antihypertensive drug classes or ≥ 4 classes regardless of blood pressure, associated with the mean estimated glomerular filtration rate (eGFR) level and its rate of decline over 4 years, compared with both controlled hypertension and uncontrolled nonresistant hypertension with ≤ 2 drugs. GFR was estimated with three different equations.

RESULTS

Baseline prevalence of apparent treatment-resistant hypertension and of controlled and uncontrolled nonresistant hypertension, were 6.5%, 62.3% and 31.2%, respectively. During follow-up, 162 participants developed apparent treatment-resistant hypertension. Mean eGFR decline with the MDRD equation was 1.5±2.9 mL/min/1.73 m² per year: 27.7% of the participants had an eGFR ≥3 and 10.1% ≥ 5 mL/min/1.73 m² per year. After adjusting for age, sex, obesity, diabetes, and cardiovascular history, the ORs for new-onset apparent treatment-resistant hypertension associated with a mean eGFR level, per 15 mL/min/1.73 m² drop, were 1.23 [95% confidence interval 0.91-1.64] compared to controlled hypertension and 1.10 [0.83-1.45] compared to uncontrolled nonresistant hypertension; ORs associated with a decline rate ≥ 3 mL/min/1.73 m² per year were 1.89 [1.09-3.29] and 1.99 [1.19-3.35], respectively. Similar results were obtained when we estimated GFR with the CKDEPI and the BIS1 equations. ORs tended to be higher for an eGFR decline rate ≥ 5 mL/min/1.73 m² per year.

CONCLUSION

The speed of kidney function decline is associated more strongly than kidney function itself with the risk of apparent treatment-resistant hypertension in the elderly.

Estimated glomerular filtration rate, urine albumin excretion, and survival among patients consulting in public Chilean public primary care clinics

Chronic renal disease (CRD) in its pre-dialysis stage is an important risk factor for mortality among adults. The aim of this study was to assess the effects of CRD on mortality among consultants in Chilean public primary care clinics. We obtained information about serum creatinine, urinary albumin excretion (UAE), blood pressure, and body mass index of 5224 consultants [3379 females aged 67 (59-75) years and 1845 males aged 68 (59-75) years] in three clinics of Metropolitan Santiago. Kaplan-Meier curves and Cox proportional hazard regression models were used to determine risk factors for mortality, determined 41 months after obtaining the blood samples. During the follow-up period, 262 patients died (33% due to circulatory causes and 29% due to tumors). Kaplan-Meier curves showed that there was a significant association between survival, estimated glomerular filtration rate, and UAE. Cox models showed that serum creatinine, UAE, a lower body mass index, and a history of diabetes were significant mortality predictors. A sensitivity analysis performed eliminating extreme ages (less than 50 and more than 80 years), included high diastolic pressure as a predictor of survival. We conclude that among patients with CRD in its pre-dialysis stage, UAE is an important predictor of survival, along with serum creatinine. A low body mass index was associated with a higher mortality.

Albuminuria is Associated With Subendocardial Viability Ratio in Chronic Kidney Disease Patients

BACKGROUND/AIMS

Albuminuria is a well-established marker of subclinical organ damage. Pulse-wave analysis (PWA) employs the technique of applanation tonometry to obtain a peripheral pulse pressure waveform, from which central hemodynamic data are derived by application of the transfer function. Using PWA we can measure the subendocardial viability ratio (SEVR) and ejection duration (ED). SEVR or the Buckberg index is a non-invasive estimate of myocardial workload, oxygen supply and perfusion and a measure of the ability of the arterial system to meet the heart`s energy requirements. ED is the duration of ventricular ejection. The objective of this study was to evaluate the relationship between albuminuria and PWA parameters in chronic kidney disease (CKD) patients.

METHODS

We studied 86 CKD patients aged 59.8±13.5 years, 56 (65.1%) were male. PWA analysis and 24-hour ambulatory blood pressure (24hABP) monitoring were performed. The following parameters were calculated: (1) aortic augmentation index with and without correction for a heart rate of 75 (Aix and AIx@ HR75), (2) SEVR, calculated as the ratio of the diastolic pressure time index and the systolic pressure time index, (3) ED, (4) estimated central aortic systolic and diastolic pressure and (5) central aortic pulse pressure calculated as the difference between estimated aortic systolic and diastolic BP. Blood samples and urine albumin-to-creatinine ratio (UACR) were analyzed; UACR values were natural log transformed (lnUACR).

RESULTS

Using CKD-EPI creatinine-cystatin C formula the eGFR in patients was 7-130 ml/min/1.73 m² (mean 32.6; SD±24.6). We found statistically significant correlation between lnUACR and cystatin C (r=0.308; P=0.004), eGFR (r=-0.219; P=0.04), hemoglobin (r=-0.255; P=0.02), phosphorus (r=0.222; P=0.04), iPTH (r=0.268; P=0.01), SEVR (r=-0.254; P=0.02) and ED (r=0.315; P=0.003). No statistically significant correlations between lnUACR and cardiac biomarkers TnI, NT-proBNP, central aortic BP and 24h ABP values were found. Using multiple regression analysis statistically significant association was found between SEVR as dependent variable and lnUACR (β=-0.223, P=0.039), sex (β=-0.216, P=0.035), and diabetes (β=0.332, P=0.001). Multiple regression analysis with ED as dependent variable has shown statistically significant association with lnUACR (β=0.242, P=0.031) and diabetes (β=-0.275, P=0.01). Patients were stratified into tertiles according to the lnUACR. Statistically significant differences in serum creatinine (P=0.001), cystatin C (P=0.012), hemoglobin (P=0.03), calcium (P=0.036), iPTH (P=0.008), SEVR (P=0.007) and ED (P=0.004) were found between tertiles. In post hoc analysis we found statistically significant differences between first and third tertile in SEVR (P=0.002; 95% CI:10.5-45) and in ED (P=0.001; 95% CI:-6.89-(-1.87)).

CONCLUSIONS

Nondialysis CKD patients with higher levels of albuminuria have lower SEVR and higher ED and our results have shown the importance of central hemodynamic parameters like are SEVR and ED as a better or earlier noninvasive hemodynamic indexes in these patients.

Albuminuria, renal dysfunction and circadian blood pressure rhythm in older men: a population-based longitudinal cohort study

Background

Both albuminuria and kidney dysfunction may affect circadian blood pressure (BP) rhythm, while exacerbating each other's effects. We investigated associations and interactions of these two risk factors with circadian BP rhythm variation and non-dipper pattern progression in community-dwelling older men.

Methods

This was a cross-sectional and longitudinal analyses in the third and fourth cycles of the Uppsala Longitudinal Study of Adult Men, including 1051 men (age 71 years) with assessments on urinary albumin excretion rate (UAER), 24-h ambulatory BP monitoring (ABPM) and cystatin-C-estimated glomerular filtration rate (eGFR). Of these, 574 men attended re-examination after 6 years. Study outcomes were ABMP changes and non-dipping BP pattern (prevalence and progression).

Results

UAER associated with circadian BP rhythm both cross-sectionally and longitudinally. Longitudinally, significant interactions were observed between UAER and kidney dysfunction (eGFR < 60 mL/min/1.73 m²) in its association with the changes of both night-time systolic BP (SBP) and night–day SBP ratio. After stratification, UAER strongly predicted night–day SBP ratio change only in those with concurrent kidney dysfunction. At re-examination, 221 new cases of non-dipper were identified. In multivariable logistic models, high UAER associated with increased likelihood of non-dipper progression, but more strongly so among individuals with concurrent kidney dysfunction. These associations were evident also in the subpopulation of non-diabetics and in participants with normal range UAER.

Conclusions

UAER associates with circadian BP rhythm variation and non-dipper progression in elderly men. Concurrent renal dysfunction modifies and exacerbates these associations.