Visit-to-visit variability in systolic blood pressure predicts development and progression of diabetic nephropathy, but not retinopathy, in patients with type 2 diabetes

Visit-to-visit variability of blood pressure and risk of diabetic retinopathy: a systematic review and meta-analysis

BACKGROUND

Diabetes mellitus (DM), a worldwide disease affecting more than 400 million people, is associated with high blood pressure (BP). In addition to macrovascular complications, high BP in DM patients is potentially linked to microvascular complications. More than 70% of DM patients have retinopathy. To our knowledge, no systematic review and meta-analysis has been conducted on the relationship between visit-to-visit variability in blood pressure and diabetic retinopathy risk.

METHODS

This systematic review and meta-analysis study was performed on the related articles. The search strategy, screening, and data selection were all checklist-based. A comprehensive search was done in three databases, including PubMed, Google Scholar, and Scopus. The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) were followed. English clinical studies published up to January 2023 contained diabetic patients as the population, retinopathy as the outcome, and visit-to-visit blood pressure as the intervention. Using the QUIPS technique, two authors independently quantify the risk of bias in included publications. The meta-analysis was conducted using R version 4.4.1. We calculated relative risk (RR) as the effect size, applying the random effect model. Standard deviation (SD) and coefficient of variation (CV), were used as measures of BP variability.

RESULTS

A total number of 8 studies with 743,315 participants were covered in this systematic review. After meta-analysis, we concluded that the group with higher SD of BP variability had 2 percent higher risk than the control group (RR = 1.02, 95% CI = 1.01-1.03, I-squared = 41%); however, results of our analysis for CV of BP variability showed no significant contrast with control group thus no increased risk was reported (RR = 1.04, 95% CI = 0.94-1.15, I-squared = 32%, P-value = 0.23).

CONCLUSION

In conclusion, an increased SD of BP variability significantly increased the relative risk for the development of retinopathy.

Blood Pressure Variability and the Progression of Chronic Kidney Disease: a Systematic Review and Meta-Analysis

BACKGROUND

Blood pressure variability (BPV) is a risk factor for poor prognosis including cardiovascular events, chronic kidney disease, and mortality, independent of elevated BP.

METHODS

We searched PubMed/Medline, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to November 23, 2022. Cohort studies reporting the association between BPV and chronic kidney disease (CKD) progression were selected. Hazard ratios were pooled using a random-effects model. Meta-regression, subgroup analyses, and sensitivity analyses were conducted.

RESULTS

A total of 23 studies were included in this systematic review and meta-analysis. Increased BPV was associated with progression of CKD (HR: 1.21, 95% CI: 1.09-1.33) and incidence of ESRD (HR: 1.08, 95% CI: 1.08-1.30). Among the different BPV metrics, high variation independent of mean (VIM), coefficient of variation (CV), standard deviation (SD), and average real variability (ARV) were indicated as predictors of CKD progression.

DISCUSSION

Increased BPV was associated with CKD progression.

Association of blood pressure with incident diabetic microvascular complications among diabetic patients: Longitudinal findings from the UK Biobank

Background

Evidence suggests a correlation of blood pressure (BP) level with presence of diabetic microvascular complications (DMCs), but the effect of BP on DMCs incidence is not well-established. We aimed to explore the associations between BP and DMCs (diabetic retinopathy, diabetic kidney disease, and diabetic neuropathy) risk in participants with diabetes.

Methods

This study included 23 030 participants, free of any DMCs at baseline, from the UK Biobank. We applied multivariable-adjusted Cox regression models to estimate BP-DMCs association and constructed BP genetic risk scores (GRSs) to test their association with DMCs phenotypes. Differences in incidences of DMCs were also compared between the 2017 ACC/AHA and JNC 7 guidelines (traditional criteria) of hypertension.

Results

Compared to systolic blood pressure (SBP)<120 mm Hg, participants with SBP≥160 mm Hg had a hazard ratio (HR) of 1.50 (95% confidence interval (CI) = 1.09, 2.06) for DMCs. Similarly, DMCs risk increased by 9% for every 10 mm Hg of higher SBP at baseline (95% CI = 1.04, 1.13). The highest tercile SBP GRS was associated with 32% higher DMCs risk (95% CI = 1.11, 1.56) compared to the lowest tercile. We found no significant differences in DMCs incidence between JNC 7 and 2017 ACC/AHA guidelines.

Conclusions

Genetic and epidemiological evidence suggests participants with higher SBP had an increased risk of DMCs, but hypertension defined by 2017 ACC/AHA guidelines may not impact DMCs incidence compared with JNC 7 criteria, contributing to the care and prevention of DMCs.

The concordance and discordance of diabetic kidney disease and retinopathy in patients with type 2 diabetes mellitus: A cross-sectional study of 26,809 patients from 5 primary hospitals in China

INTRODUCTION

Diabetic kidney disease (DKD) and diabetic retinopathy (DR) share similar pathophysiological mechanisms. However, signs of DKD may be present at diagnosis of diabetes without retinopathy. Risk factors for the development of DKD and DR may not be identical.

METHODS

This study aimed to evaluate the concordance and discordance between DKD and DR by investigating the distribution of DKD and DR in patients with type 2 diabetes mellitus from 5 Chinese cities. A total of 26,809 patients were involved in this study. The clinical characteristics were compared among patients based on the presence of DKD and DR. Logistic regression models were used to analyze the independent risk factors of DKD and DR.

RESULTS

The prevalence of DKD and DR was 32.3% and 34.6%, respectively. Among eligible patients, 1,752 patients without DR had an increased urinary albumin-to-creatinine ratio (ACR) or reduced estimated glomerular filtration rate (eGFR), and 1,483 patients with DR had no DKD. The positive predictive value of DR for DKD was 47.4% and negative predictive value was 67.1%. Elder age, male gender, a longer duration of disease, higher values of waist circumference and HbA1c were associated with both DR and DKD. A lower educational level was associated with DR. Higher BP and TG would predict increased prevalence of DKD.

CONCLUSIONS

DKD and DR shared many risk factors, but a significant discordance was present in patients with type 2 diabetes mellitus. DKD was more strongly associated with blood pressure and triglycerides than DR.

Day-to-Day Blood Pressure Variability and Risk of Incident Chronic Kidney Disease in a General Japanese Population

Background Several longitudinal studies have reported that higher visit-to-visit blood pressure variability is associated with greater risk for developing chronic kidney disease. However, no population-based studies have investigated the association between day-to-day home blood pressure variability and incident chronic kidney disease. Methods and Results A total of 2342 Japanese community-dwelling residents aged ≥40 years without chronic kidney disease at baseline were followed up by annual health examinations for 10 years. Home blood pressure was measured 3 times every morning for 28 days. Day-to-day coefficients of variation of home systolic blood pressure levels were categorized into quintiles. Chronic kidney disease was defined as an estimated glomerular filtration rate <60 mL/min per 1.73 m² or the presence of proteinuria. The hazard ratios for developing chronic kidney disease were estimated with a Cox proportional hazards model. During the follow-up period, 772 participants developed chronic kidney disease. Increased coefficients of variation of home systolic blood pressure were associated significantly with higher risk of chronic kidney disease after adjusting for confounders (P for trend <0.001): Individuals in the highest quintile of coefficients of variation had a 1.50-fold (95% CI, 1.17-1.94) greater risk of developing chronic kidney disease than those in the lowest quintile. The combination of higher coefficients of variation and higher mean value of home systolic blood pressure was associated with the multivariable-adjusted risk of developing chronic kidney disease. Conclusions These findings suggest that increased day-to-day blood pressure variability is a significant risk factor for developing chronic kidney disease in a general Japanese population.

Blood pressure variability in individuals with diabetes mellitus: a scoping review

OBJECTIVES

to map methods and devices used to assess very short-, short-, medium-, and long-term pressure variability in adults with type 1 or 2 diabetes mellitus.

METHODS

scoping review conducted in January and February 2021 in MEDLINE, Web of Science, CINAHL, LILACS, PubMed, and Embase databases. Studies conducted within the last ten years analyzing pressure variability in adult and older patients with diabetes mellitus type 1 or 2 were included. Studies that used discontinued devices were excluded.

RESULTS

the sample was composed of 25 articles published since 2017, with the majority developed in Japan (n=11); with the predominance of the oscillometric method (n=22); the most used devices were from the Omron® brand (n=14); the most detected type was long-term variability (n=10).

CONCLUSIONS

we observed the increasing application of the oscillometric method for pressure variability analysis with various brands and models of automatic devices.

Effect of blood pressure trajectory and variability on new-onset chronic kidney disease in patients with type 2 diabetes

This study aimed to evaluate the effects of BP trajectory and variability on chronic kidney disease (CKD) incidence in patients with type 2 diabetes. This retrospective longitudinal study included 4,560 participants with type 2 diabetes, aged ≥30 years, free of CKD, with ≥3 years of follow-up, and who attended the Diabetes Care Management Program in 2001-2013. The follow-up period ended in 2016. The adverse outcome was a new-onset CKD event, which was determined using eGFR and albuminuria. Cox proportional hazards models were used to assess the associations. At the end of the follow-up, 1255 participants had developed CKD, with a mean follow-up of 4.3 ± 3.2 years. Three trajectory subgroups of BP, i.e., Cluster 1: "moderate-stable" for SBP and "moderate-downward" for DBP, Cluster 2: "low-upward-downward" for both SBP and DBP, and Cluster 3: "high-downward-upward" for both SBP and DBP, were generated. The BP variability was grouped into three classes on the basis of tertiles. For the BP trajectory, patients in Cluster 3 of DBP had a higher CKD risk than those in Cluster 1 (HR = 1.24, 95% CI = 1.03-1.50). For the BP variability, patients in Tertile 3 had a significantly higher CKD risk than those in Tertile 1 (SBP: 1.28, 1.11-1.47; DBP: 1.17, 1.02-1.34). Persons with type 2 diabetes who achieved a small reduction in DBP after participating in the education program but rebounded and those who had the highest variation in both SBP and DBP faced the highest increase in CKD risk.

The Impact of Systolic Blood Pressure, Pulse Pressure, and Their Variability on Diabetes Retinopathy among Patients with Type 2 Diabetes

OBJECTIVES

To evaluate the effects of variations in systolic blood pressure (SBP) and pulse pressure (PP) on diabetic retinopathy (DR) in patients with type 2 diabetes.

METHODS

A total of 3275 type 2 diabetes patients without DR at Taiwan Lee's United Clinic from 2002 to 2014 were enrolled in the study. The average age of the patients was 65.5 (±12.2) years, and the follow-up period ranged from 3 to 10 years. Blood pressure variability was defined as the standard deviation (SD) of the average blood pressure values over the entire study period and was calculated for each patient. The mean SD for SBP was 11.16, and a SBP ≥ 130 mmHg (1 mmHg = 0.133 kPa) was defined as high SBP. Based on these data, patients were divided into four groups as follows: group 1 (G1, mean SBP < 130 mmHg, SD of SBP < 11.16 mmHg), group 2 (G2, mean SBP < 130 mmHg, SD ≥ 11.16 mmHg), group 3 (G3, mean SBP ≥ 130 mmHg, SD of SBP < 11.16 mmHg), and group 4 (G4, mean SBP ≥ 130 mmHg, SD ≥ 11.16 mmHg). Based on a mean PP of 80 mmHg with a pulse pressure SD of 6.53 mmHg, the patients were regrouped into four groups designated G1'-G4'.

RESULTS

After adjusting for patient age, sex, and disease course, Cox regression showed that the mean and SD of SBP, pulse pressure, and their SDs were risk factors for DR. After stratifying the patients based on the mean and SD of the SBP, we found that the patients in the G4 group had the highest risk of DR (hazard ratio (HR) = 1.980, 95% CI: 1.716~2.285, P < 0.01) and patients in the G1 group had the lowest risk. Patients in the G3 group (HR = 1.409, 95% CI: 1.284~1.546, P < 0.01) had a higher risk of DR compared to those in the G2 group (HR = 1.353, 95% CI: 1.116~1.640, P < 0.01). After the restratification of patients based on the mean and SD of the pulse pressures, it was found that patients in the G2' group had the highest risk of DR (HR = 2.086, 95% CI: 1.641~2.652, P < 0.01), whilst patients in the G1' group had the lowest risk. Also, the risk of DR in the G4' group (HR = 1.507, 95% CI: 1.135~2.000, P < 0.01) was higher than that in the G3' group (HR = 1.289, 95% CI: 1.181~1.408, P < 0.01).

CONCLUSIONS

Variability in SBP and PP are risk factors for DR in patients with type 2 diabetes. The variability of PP was better able to predict the occurrence of DR than mean pulse pressure.

Study of serum pentraxin 3 level in patients with diabetic nephropathy

Background

Pentraxin 3 (PTX3), a member of a superfamily of conserved proteins called pentraxins. PTX3 and C-reactive protein (CRP) are members of this family and play an important role in the innate immune system. PTX3 is classified as a long pentraxin, while CRP is a short pentraxin. PTX3 is reported to be a vascular inflammatory marker providing prognostic information of vasculopathy, such as diabetic nephropathy (DN). The purpose of this study is to evaluate the association between serum PTX3 concentrations and the development and/or progression of DN. A total number of 66 patients with type 2 diabetes mellitus (T2DM) and 22 healthy subjects were enrolled in this study. Patients with T2DM were divided, according to the levels of urinary albumin/creatinine ratio (UACR), into three groups: normoalbuminuric, microalbuminuric, and macroalbuminuric groups. Serum PTX3 and high-sensitivity C-reactive protein (hs-CRP) concentrations were determined using ELISA kits.

Results

Serum PTX3 and hs-CRP concentrations were significantly higher in patients with T2DM compared with the controls. Furthermore, serum PTX3 concentrations were significantly higher in macroalbuminuric patients than in microalbuminuric patients (P < 0.001) and also were significantly higher in microalbuminuric patients than in normoalbuminuric patients (P < 0.001). However, there were no significant differences between controls and T2DM patients with normoalbuminuria regarding serum PTX3 concentrations (P > 0.05). Moreover, like PTX3, hs-CRP concentrations were higher in microalbuminuric patients than in normoalbuminuric patients (P < 0.05), and also, there were no significant differences between controls and T2DM patients with normoalbuminuria regarding hs-CRP concentrations (P > 0.05). But, unlike PTX3, there were no significant differences between macroalbuminuric and microalbuminuric patients regarding hs-CRP concentrations (P > 0.05).

Conclusions

Serum PTX3 is positively associated with DN development and progression, and may be a more accurate predictor of DN development than hs-CRP as it can discriminate between macroalbuminuric and microalbuminuric DN patients, while hs-CRP cannot.

Visit-to-visit blood pressure variability and risk of chronic kidney disease: A systematic review and meta-analyses

Objective

Previous studies have shown that visit-to-visit blood pressure variability (BPV) is associated with chronic kidney disease (CKD). However, the results have not been consistent among studies. This systematic review and meta-analysis was conducted to comprehensively assess the association between visit-to-visit BPV and the risk of CKD.

Methods

Medline, Embase, and the Cochrane Library were searched from the date of inception through 1 August 2019 using the terms “blood pressure variability,” “chronic kidney disease,” “nephropathy,” and other comparable terms. The primary outcome was the development of CKD. Two reviewers extracted the data independently. Meta-analysis was performed using a random effects model.

Results

Fourteen studies were included in the systematic review and meta-analysis. The risk of CKD was significantly greater in patients with high baseline systolic blood pressure variability (SBPV) than in patients with low baseline SBPV: the standard deviation (SD) showed relative risk (RR) of 1.69 and 95% CI of 1.38–2.08, the coefficient of variation (CV) showed RR of 1.23 and 95% CI of 1.12–1.36, and variance independent of mean (VIM) showed RR of 1.40 and 95% CI of 1.15–1.71. RRs for each unit increase in visit-to-visit SBPV and risk of CKD were 1.05 (95% CI: 1.03–1.07) for SD, 1.06 (95% CI: 1.03–1.09) for CV, and 1.1 (95% CI: 0.96–1.25) for VIM. Diastolic BPV was similarly predictive of CKD based on SD and CV.

Conclusions

Increased visit-to-visit BPV might be an independent risk factor for CKD. However, significant heterogeneity was present; thus, future prospective studies are needed to confirm our findings. Our results indicate that treatment of hypertension should control blood pressure levels and prevent abnormal fluctuations in blood pressure to reduce the risk of CKD.

Prognostic importance of visit-to-visit blood pressure variability for micro- and macrovascular outcomes in patients with type 2 diabetes: The Rio de Janeiro Type 2 Diabetes Cohort Study

BACKGROUND

The prognostic importance of an increased visit-to-visit blood pressure variability (BP-VVV) for the future development of micro- and macrovascular complications in type 2 diabetes has been scarcely investigated and is largely unsettled. We aimed to evaluate it in a prospective long-term follow-up study with 632 individuals with type 2 diabetes.

METHODS

BP-VVV parameters (systolic and diastolic standard deviations [SD] and variation coefficients) were measured during the first 24-months. Multivariate Cox analysis, adjusted for risk factors and mean BP levels, examined the associations between BP-VVV and the occurrence of microvascular (retinopathy, microalbuminuria, renal function deterioration, peripheral neuropathy) and macrovascular complications (total cardiovascular events [CVEs], major adverse CVEs [MACE] and cardiovascular and all-cause mortality). Improvement in risk discrimination was assessed by the C-statistic and integrated discrimination improvement (IDI) index.

RESULTS

Over a median follow-up of 11.3 years, 162 patients had a CVE (132 MACE), and 212 patients died (95 from cardiovascular diseases); 153 newly-developed or worsened diabetic retinopathy, 193 achieved the renal composite outcome (121 newly-developed microalbuminuria and 95 deteriorated renal function), and 171 newly-developed or worsened peripheral neuropathy. Systolic BP-VVV was an independent predictor of MACE (hazard ratio: 1.25, 95% CI 1.03-1.51 for a 1-SD increase in 24-month SD), but not of total CVEs, cardiovascular and all-cause mortality, and of any microvascular outcome. However, no BP-VVV parameter significantly improved cardiovascular risk discrimination (increase in C-statistic 0.001, relative IDI 0.9%).

CONCLUSIONS

Systolic BP-VVV was an independent predictor of MACE, but it did not improve cardiovascular risk stratification. The goal of anti-hypertensive treatment in patients with type 2 diabetes shall remain in controlling mean BP levels, not on decreasing their visit-to-visit variability.

Visit-to-visit variability of glycemia and vascular complications: the Hoorn Diabetes Care System cohort

BACKGROUND

Glycemic variation has been suggested to be a risk factor for diabetes-related complications. Previous studies did not address confounding of diabetes duration, number of visits and length of follow-up. Here, we characterize glycemic variability over time and whether its relation to diabetes-related complications and mortality is independent from diabetes- and follow-up duration.

MATERIALS AND METHODS

Individuals with type 2 diabetes (n = 6770) from the Hoorn Diabetes Care System cohort were included in this study. The coefficient of variation (CV) was calculated over 5-year sliding intervals. People divided in quintiles based on their CV. Cox proportional hazard models were used to investigate the role of glycemic CV as risk factor in diabetes-related complications and mortality.

RESULTS

The coefficient of variation of glucose (FG-CV) increased with time, in contrast to HbA1c (HbA1c-CV). People with a high FG-CV were those with an early age of diabetes onset (Δ_Q5-Q1 = - 2.39 years), a higher BMI (Δ_Q5-Q1 = + 0.92 kg/m²), an unfavorable lipid profile, i.e. lower levels of HDL-C (Δ_Q5-Q1 = - 0.06 mmol/mol) and higher triglycerides (Δ_Q5-Q1 =+ 1.20 mmol/mol). People with the highest FG-CV in the first 5-year interval showed an increased risk of insulin initiation, retinopathy, macrovascular complications and mortality independent of mean glycemia, classical risk factors and medication use. For HbA1c, the associations were weaker and less consistent.

CONCLUSIONS

Individuals with a higher FG-CV have an unfavorable metabolic profile and have an increased risk of developing micro- and macrovascular complications and mortality. The association of HbA1c-CV with metabolic outcomes and complications was less consistent in comparison to FG-CV.

Association between blood pressure variability, cardiovascular disease and mortality in type 2 diabetes: A systematic review and meta-analysis

AIM

To investigate the associations of blood pressure variability (BPV), expressed as long-term (visit-to-visit) and short-term (ambulatory blood pressure monitoring [ABPM] and home blood pressure monitoring [HBPM]) and all-cause mortality, major adverse cardiovascular events (MACEs), extended MACEs, microvascular complications (MiCs) and hypertension-mediated organ damage (HMOD) in adult patients with type 2 diabetes.

MATERIALS AND METHODS

PubMed, Medline, Embase, Cinahl, Web of Science, ClinicalTrials.gov and grey literature databases were searched for studies including patients with type 2 diabetes, at least one variable of BPV (visit-to-visit, HBPM, ABPM) and evaluation of the incidence of at least one of the following outcomes: all-cause mortality, MACEs, extended MACEs and/or MiCs and/or HMOD. The extracted information was analyzed using random effects meta-analysis and meta-regression.

RESULTS

Data from a total of 377 305 patients were analyzed. Systolic blood pressure (SBP) variability was associated with a significantly increased risk of all-cause mortality (HR 1.12, 95% CI 1.04-1.21), MACEs (HR 1.01, 95% CI 1.04-1.17), extended MACEs (HR 1.07, 95% CI 1.03-1.11) and MiCs (HR 1. 12, 95% CI 1.01-1.24), while diastolic blood pressure was not. Associations were mainly driven from studies on long-term SBP variability. Qualitative analysis showed that BPV was associated with the presence of HMOD expressed as carotid intima-media thickness, pulse wave velocity and left ventricular hypertrophy. Results were independent of mean blood pressure, glycaemic control and serum creatinine levels.

CONCLUSIONS

Our results suggest that BPV might provide additional information rather than mean blood pressure on the risk of cardiovascular disease in patients with type 2 diabetes.

Clinical characteristics of diabetic nephropathy in patients with type 2 diabetic mellitus manifesting heavy proteinuria: A retrospective analysis of 220 cases

AIMS

To determine the predictability of diagnosing diabetic nephropathy (DN) versus non-diabetic renal disease (NDRD) from clinical and laboratory data in Chinese patients with type 2 diabetes mellitus (T2DM) manifesting heavy proteinuria.

METHODS

We retrospectively analyzed the clinical and laboratory data of patients with T2DM manifesting heavy proteinuria who underwent renal biopsy from January 2014 to December 2017.

RESULTS

According to renal biopsy, 220 patients were finally enrolled, including 109 cases diagnosed with DN alone (49.55%), 94 with NDRD alone (42.73%) and 17 with DN plus superimposed NDRD (7.73%). Multivariate analysis showed the significant risk factors for DN alone were age, duration of diabetes, presence of retinopathy, 24-h proteinuria, serum albumin and SBP. Presence of retinopathy achieved the highest overall diagnostic efficiency with the area under the curve of 0.852, sensitivity of 78.9% and specificity of 91.5%. The combined diagnosis with four indicators (duration of diabetes, retinopathy, SBP, and serum albumin) showed the area under the curve of 0.938, sensitivity of 88.1% and specificity of 87.2%.

CONCLUSIONS

The prevalence of DN is high in patients with T2DM manifesting heavy proteinuria. Renal biopsy should be performed in diabetics in the atypical clinical scenario.

Prognostic value of visit-to-visit systolic blood pressure variability related to diabetic kidney disease among patients with type 2 diabetes

BACKGROUND

This study aimed to evaluate the impact of visit-to-visit variability (VVV) of blood pressure on the risk of diabetic nephropathy and whether it provides additional predictive information among patients with type 2 diabetes mellitus (T2DM) in China.

METHODS

We included 12 630 T2DM patients during January 2008-December 2012 using a retrospective cohort design. VVV of SBP was assessed as standard deviation, coefficient of variation and variation independent of mean of the blood pressure readings during the measurement period. Hazard ratios and 95% confidence intervals were estimated for the associations of variability in SBP with risk of diabetes nephropathy by using Cox proportional hazards regression models. Risk prediction ability was assessed using C statistic, integrated discrimination improvement (IDI) and net reclassification index (NRI).

RESULTS

We found a dose-response relationship across quartiles of VVV SBP (P trend < 0.001). Hazard ratio in the highest quartile of SD SBP (≥9.2 mmHg) was 1.49 (1.16-1.93) as compared with the lowest quartile (<4.8 mmHg) after adjusted for mean SBP values, max SBP values and other covariates. Addition of SD SBP significantly improved risk prediction for diabetic kidney disease (DKD) [C statistic (from 0.664 to 0.673), IDI (0.0011, 95% CI: 0.0003-0.0104) and NRI (0.053, 95% CI: 0.0017-0.113)]. Results remained similar across different subgroups, sensitivity analyses or using coefficient of variation and variance independent of mean.

CONCLUSION

VVV of SBP is a significant risk factor of DKD among T2DM patients on top of mean and max BP values, which provides additional significant predictive information.

Discordance in risk factors for the progression of diabetic retinopathy and diabetic nephropathy in patients with type 2 diabetes mellitus

AIMS/INTRODUCTION

We aimed to investigate whether there are differences in the risk factors or markers for the progression of diabetic retinopathy (DR) and diabetic nephropathy (DN) in type 2 diabetes mellitus.

MATERIALS AND METHODS

We carried out a 3-year retrospective cohort study of 604 patients with type 2 diabetes mellitus. The outcomes were the progression of DR (worsening of the DR stage) and DN (an estimated glomerular filtration rate decline >12%) at the 3-year follow up. The mean hemoglobin A1c (HbA1c) level and HbA1c variability (HbA1c-VAR) were calculated.

RESULTS

The mean HbA1c and HbA1c-VAR levels were higher in the DR progressors (n = 67) than in the DR non-progressors (n = 537). The mean HbA1c was a significant predictor for DR progression independent of the duration of diabetes and HbA1c-VAR levels. The urine albumin-to-creatinine ratio at baseline and HbA1c-VAR levels were higher in the DN progressors (n = 34) than in the DN non-progressors (n = 570). The triglyceride to high-density lipoprotein cholesterol ratio at baseline tended to be higher in the DN progressors than in the DN non-progressors. HbA1c-VAR levels and the triglyceride-to-high-density lipoprotein cholesterol ratio were significant predictors for DN progression independent of estimated glomerular filtration rate and the urine albumin-to-creatinine ratio.

CONCLUSIONS

Average glycemia was significantly associated with progression of DR, whereas glycemic variability and dyslipidemia were significantly associated with progression of DN in type 2 diabetes mellitus.

Diabetic Nephropathy in Type 2 Diabetic Retinopathy Requiring Panretinal Photocoagulation

PURPOSE

To investigate the risk factors of diabetic nephropathy in patients with diabetic retinopathy requiring panretinal photocoagulation (PRP) and the visual prognosis.

METHODS

A retrospective review of electronic medical records was conducted at Seoul St. Mary's Hospital, comprising 103 patients with type 2 diabetes mellitus and diabetic retinopathy who underwent PRP from 1996 to 2005. Patients with type 1 diabetes mellitus, non-diabetic renal disease, non-diabetic retinal disease, visually significant ocular disease, high-risk proliferative diabetic retinopathy, and advanced diabetic retinopathy were excluded. The patients were divided into three groups: no nephropathy (group 1, n = 45), microalbuminuria (group 2, n = 16), and advanced nephropathy (group 3, n = 42). Duration of diagnosis of retinopathy and nephropathy, glycosylated hemoglobin, visual acuity, complications, and treatment history were investigated.

RESULTS

The mean glycosylated hemoglobin of group 3 (8.4 ± 1.2) was higher than that of group 1 (7.7 ± 1.0) or group 2 (7.7 ± 1.0) (p = 0.04). Mean interval from PRP to diagnosis of nephropathy was 8.8 ± 6.0 years in group 2 and 8.7 ± 4.9 years in group 3. The significant decrease in visual acuity in group 3 (28 eyes, 35.9%) was significantly higher than that in group 1 (15 eyes, 18.1%, p = 0.01) or group 2 (6 eyes, 20.7%, p = 0.03). Only vitreous hemorrhage showed a significantly higher incidence in groups 2 and 3 than in group 1 (p = 0.02). Multivariate regression analysis revealed that female sex and lower glycosylated hemoglobin were significantly associated with a protective effect on development of nephropathy.

CONCLUSIONS

In the clinical setting, many patients with PRP-requiring diabetic retinopathy develop nephropathy an average of 8 to 9 years after PRP. Male sex and higher glycosylated hemoglobin could be risk factors of nephropathy.

Blood Pressure Variability and Autonomic Dysfunction

PURPOSE OF REVIEW

This review considers the relationship between abnormal blood pressure (BP) variability and autonomic dysfunction through an attempt to answer questions about its clinical relevance and pertinence to diabetes and cardiovascular autonomic neuropathy (CAN) and which therapeutic measures can lessen its cardiovascular impact.

RECENT FINDINGS

Office, ambulatory, and home BP monitoring identify posture-related, circadian, short-term, and long-term BP variabilities. Abnormal BP variability is a risk marker for organ damage, mortality, and cardiovascular events. Moreover, BP variability changes are common in diabetes and associated with CAN and possibly exacerbated by comorbidities like nephropathy, obstructive sleep apnoea syndrome, and chronic pain. The prognostic role of nondipping and reverse dipping is well documented in diabetes. Some findings suggest the possibility of restoring dipping with the dosage time of antihypertensive agents. Diabetes is a favorable scenario for altered BP variability, which might mediate the harmful effects of CAN. Preliminary data suggest the protective effect of targeting BP variability. However, further longitudinal outcome studies are needed. In the meantime, BP variability measures and practical expedients in antihypertensive treatment should be implemented in diabetes.

Predictive ability of visit-to-visit variability in HbA1c and systolic blood pressure for the development of microalbuminuria and retinopathy in people with type 2 diabetes

AIMS

We explored whether visit-to-visit variability in both glycated hemoglobin (HbA1c) and systolic blood pressure (SBP) simultaneously predicted the development of microalbuminuria and retinopathy, and whether the predictive ability of these measurements changed according to mean HbA1c and SBP levels in people with type 2 diabetes.

METHODS

A retrospective observational cohort study was conducted on 243 type 2 diabetes patients with normoalbuminuria and 486 without retinopathy at the first visit and within 1year thereafter. The two cohorts were followed up from 1995 until 2012. Multivariate and stratified analyses were performed using Cox proportional hazard models.

RESULTS

Microalbuminuria developed in 84 patients and retinopathy in 108. Hazard ratios (HRs) for the development of microalbuminuria associated with the coefficient of variation (CV) and variation independent of mean (VIM) of both HbA1c and SBP significantly increased. In participants with a mean SBP <130mmHg, the HRs for the development of retinopathy associated with CV and VIM of HbA1c were abruptly elevated and significant compared with those with a mean SBP ≥130mmHg.

CONCLUSIONS

Visit-to-visit variability in both HbA1c and SBP simultaneously predict the development of microalbuminuria. HbA1c variability may predict the development of retinopathy when the mean SBP is normal (<130mmHg).

HbA1c, systolic blood pressure variability and diabetic retinopathy in Asian type 2 diabetics

BACKGROUND

The aim of the present study was to examine the association between variability in HbA1c or systolic blood pressure (SBP) and diabetes-specific moderate retinopathy in Asians with type 2 diabetes (T2D).

METHODS

A retrospective study was conducted of 172 cases of moderate diabetic retinopathy (DR) cases and 226 controls without DR, matched for age, sex, and ethnicity. Serial HbA1c and SBP (range 3-6 readings) over the 2 years prior to photographic screening of DR were collected. Intrapersonal mean and SD values for HbA1c (iM-HbA1c and iSD-HbA1c) and SBP (iM-SBP and iSD-SBP) were derived. Moderate DR was assessed from digital retinal photographs and defined as levels >43 using the Early Treatment Diabetic Retinopathy Study scale.

RESULTS

Cases of moderate DR had higher iM-HbA1c (8.2 % vs 7.3 %; P = 0.001), iSD-HbA1c (1.22 vs 0.64; P = 0.001), iM-SBP (136.8 vs 129.6 mmHg; P = 0.001) and iSD-SBP (13.3 vs 11.1; P = 0.002) than controls. In the multivariate regression model adjusted for age, gender, ethnicity, duration of diabetes, SBP, and HbA1c, iM-HbA1c and iM-SBP were significantly associated with moderate DR (odds ratio [OR] 1.80, 95 % confidence interval [CI] 1.37-2.36; and OR 1.03, 95 % CI 1.01-1.05, respectively). Neither iSD-HbA1c nor iSD-SBP were associated with moderate DR. When stratified by HbA1c <7 %, only iSD-SBP remained significantly associated with moderate DR (OR 1.11, 95 % CI 1.01-1.21).

CONCLUSION

In a cohort of Asian patients with T2D, both higher mean HbA1c levels and SBP, but not their variability, were associated with moderate DR. Among those with good glycemic control, wider variability of SBP is associated with moderate DR.

Visit-to-visit systolic blood pressure variability and microvascular complications among patients with diabetes

AIMS

To examine the relationship between systolic blood pressure (SBP) variability and the risk of microvascular complications in a non-elderly diabetic population.

METHODS

This is a retrospective cohort study of individuals aged ≤60years treated for diabetes in 2003 in the US Department of Veterans Affairs healthcare system. Individuals were followed for five years for any new diagnosis of diabetic nephropathy, retinopathy, or neuropathy. In each year of follow-up, individuals were classified into quartiles based on their SBP variability.

RESULTS

We identified 208,338 patients with diabetes without diabetic nephropathy, retinopathy, or neuropathy at baseline. Compared to individuals with the least SBP variability (Quartile 1), those with most variability (Quartile 4) had 81% (OR=1.81; 95% CI, 1.72-1.91), 17% (OR=1.17; 95% CI, 1.13-1.21), 30% (OR=1.30; 95% CI, 1.25-1.35), and 19% (OR=1.19; 95% CI, 1.15-1.23) higher incidence of nephropathy, retinopathy, neuropathy, and any complication, respectively, after adjusting for mean SBP, demographic and clinical factors.

CONCLUSIONS

We found a significant graded relationship between SBP variability and the incidence of each complication and of any combined endpoint. This is the first study showing a significant association between SBP variability and the risk of diabetic retinopathy and neuropathy.

Psychosocial stress and changes in estimated glomerular filtration rate among adults with diabetes mellitus

BACKGROUND

Psychosocial stress has been hypothesized to impact renal changes, but this hypothesis has not been adequately tested. The aim of this study was to examine the relationship between psychosocial stress and estimated glomerular filtration rate (eGFR) and to examine other predictors of eGFR changes among persons with diabetes mellitus (DM).

METHODS

Data from a survey conducted in 2005 by a major health maintenance organization located in the southeastern part of the United States, linked to patients' clinical and pharmacy records (n=575) from 2005 to 2008, was used. Study participants were working adults aged 25-59 years, diagnosed with DM but without advanced microvascular or macrovascular complications. eGFR was estimated using the Modification of Diet in Renal Disease equation. A latent psychosocial stress variable was created from five psychosocial stress subscales. Using a growth factor model in a structural equation framework, we estimated the association between psychosocial stress and eGFR while controlling for important covariates.

RESULTS

The psychosocial stress variable was not directly associated with eGFR in the final model. Factors found to be associated with changes in eGFR were age, race, insulin use, and mean arterial pressure.

CONCLUSION

Among fairly healthy DM patients, we did not find any evidence of a direct association between psychosocial stress and eGFR changes after controlling for important covariates. Predictors of eGFR change in our population included age, race, insulin use, and mean arterial pressure.

Time-to-effect relationships between systolic blood pressure and the risks of nephropathy and retinopathy in patients with type 2 diabetes

AIMS

To analyze time-to-effect relationships between systolic blood pressure (SBP) and the risks of development of nephropathy and retinopathy in patients with type 2 diabetes.

METHODS

We retrospectively enrolled 647 patients with type 2 diabetes who first visited our hospital between 1995 and 1996, made ≥1 hospital visit per year, had been followed-up for ≥1year, and had undergone ≥4 SBP measurements. Of these, 352 with normoalbuminuria and 516 without retinopathy were followed through June 2012.

RESULTS

Nephropathy developed in 90 patients and retinopathy in 113. Hazard ratios (HRs) for time-dependent SBP-associated nephropathy and retinopathy were the highest during 1year preceding each endpoint or censoring. The HRs for nephropathy had been steadily lower during the preceding 1-17 years, while that for retinopathy had been lower during the preceding 1-5 years and constant during the preceding 5-17 years.

CONCLUSIONS

The time-to-effect relationship with SBP differed for the development of nephropathy and retinopathy. The long-term effect was obvious for nephropathy and borderline for retinopathy, while the short-term effect was stronger and evident for both. Continuous SBP lowering is necessary to prevent nephropathy, whereas SBP control during the preceding 5years seems to be important to prevent retinopathy.