Tight blood pressure control in diabetes: evidence-based review of treatment targets in patients with diabetes

Treatment strategies for isolated systolic hypertension in elderly patients

INTRODUCTION

Hypertension is a major and modifiable risk factor for cardiovascular disease. Its prevalence is rising as the result of population aging. Isolated systolic hypertension mostly occurs in older patients accounting for up to 80% of cases.

AREAS COVERED

The authors systematically review published studies to appraise the scientific and clinical evidence supporting the role of blood pressure control in elderly patients with isolated systolic hypertension, and to assess the influence of different drug treatment regimens on outcomes.

EXPERT OPINION

Antihypertensive treatment of isolated systolic hypertension significantly reduces the risk of morbidity and mortality in elderly patients. Thiazide diuretics and dihydropyridine calcium-channel blockers are the primary compounds used in randomized clinical trials. These drugs can be considered as first-line agents for the management of isolated systolic hypertension. Free or fixed combination therapy with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers and calcium-channel blockers or thiazide-like diuretics should also be considered, particularly when compelling indications such as coronary artery disease, chronic kidney disease, diabetes, and congestive heart failure coexist. There is also hot scientific debate on the optimal blood pressure target to be achieved in elderly patients with isolated systolic hypertension, but current recommendations are scarcely supported by evidence.

Treatment of Diabetes in Older Adults: An Endocrine Society* Clinical Practice Guideline

OBJECTIVE

The objective is to formulate clinical practice guidelines for the treatment of diabetes in older adults.

CONCLUSIONS

Diabetes, particularly type 2, is becoming more prevalent in the general population, especially in individuals over the age of 65 years. The underlying pathophysiology of the disease in these patients is exacerbated by the direct effects of aging on metabolic regulation. Similarly, aging effects interact with diabetes to accelerate the progression of many common diabetes complications. Each section in this guideline covers all aspects of the etiology and available evidence, primarily from controlled trials, on therapeutic options and outcomes in this population. The goal is to give guidance to practicing health care providers that will benefit patients with diabetes (both type 1 and type 2), paying particular attention to avoiding unnecessary and/or harmful adverse effects.

Gender Differences and Risk Factors of Recurrent Stroke in Type 2 Diabetic Malaysian Population with History of Stroke: The Observation from Malaysian National Neurology Registry

BACKGROUND AND PURPOSE

Diabetes mellitus has been reported as a strong independent risk factor for stroke recurrence. Data on the modifiable factors contributing to the recurrence of stroke in type 2 diabetic Malaysian population with a history of stroke stratified by genders are lacking, and this supports the importance of this study.

METHOD

The data of 4622 patients with T2DM who had a history of stroke was obtained from the Malaysian National Stroke Registry. Univariate analysis was performed to differentiate between genders with and without stroke recurrence in terms of demographics, first stroke attack presentations, and other clinical characteristics. The significant factors determined from the univariate analysis were further investigated using logistic regression.

RESULTS

Ischemic heart diseases were found significantly associated with the stroke recurrence in males (OR = 1.738; 95% CI: 1.071-2.818) as well as female (OR = 5.859; 95% CI: 2.469-13.752) diabetic patients. The duration of hypertension, as well as the duration of diabetes, has been associated with the recurrence in both male and female subjects (p value < 0.05). Smoking status has an impact on the stroke recurrence in male subjects, while no significant association was observed among their peers.

CONCLUSIONS

Most of the predictive factors contributing to the recurrence of stroke in type 2 diabetic Malaysian population with a history of stroke are modifiable, in which IHD was the most prominent risk factor in both genders. The impact of optimizing the management of IHD as well as blood glucose control on stroke recurrence may need to be elucidated. No major differences in recurrent stroke predictors were seen between genders among the Malaysian population with type 2 diabetes mellitus who had a previous history of stroke.

Systolic blood pressure target in systemic arterial hypertension: Is lower ever better? Results from a community-based Caucasian cohort

BACKGROUND

Extensive evidence exists about the prognostic role of systolic blood pressure (SBP) reduction ≤140mmHg. Recently, the SPRINT trial successfully tested the strategy of lowering SBP<120mmHg in patients with arterial hypertension (AH).

AIM

To assess whether the SPRINT results are reproducible in a real world community population.

METHODS

Cross-sectional, population-based study analyzing data of 24,537 Caucasian people with AH from the Trieste Observatory of CV disease, 2010 to 2015. We selected and divided 2306 subjects with AH according to the SPRINT trial criteria; similarly, SPRINT clinical outcomes were considered.

RESULTS

Study patients median age was 75±8years, two third male, one third had ischemic heart disease. They were older, with lower body mass index, higher SBP and Framingham CV risk score than the SPRINT patients. Three-hundred-sixty-eight patients (16%) had SBP<120mmHg. During 48 [36-60] months of follow-up, 751 patients (32%) experienced a major adverse cardiac event (MACE). The SBP <120mmHg group had higher incidence of MACE, CV deaths and all-cause death than SBP≥120mmHg group (37% vs 31%; 10% vs 4%; 19% vs 10%, all p<0.05). The condition of SBP<120mmHg was an independent predictor of MACE in multivariate Cox analysis together with older age, male gender, higher Charlson score.

CONCLUSIONS

In our experience, the SBP<120mmHg condition is associated with worse clinical outcomes, suggesting the SPRINT results are not reproducible tout court in Caucasian community populations. These differences should be taken as a warning against aggressive reducing of SBP<120mmHg.

Ahsan C. Hypertension in diabetes and the risk of cardiovascular disease

Hypertension (HTN) is an important risk factor for cardiovascular disease and its many manifestations. It shares pathogenic pathways with diabetes and is part of a common metabolic entity, the metabolic syndrome. When combined with diabetes, HTN has been shown to predict and promote increased risk for cardiovascular disease events over and above each risk factor alone. Of the components of this metabolic syndrome, HTN is relatively easy to diagnose and thereby more accessible for implementing preventive and treatment strategies. The recent release of Joint National Committee-8 guidelines for the treatment of HTN has fueled a debate on treatment target goals.

Prevalence of resistant hypertension and associated factors in Japanese subjects with type 2 diabetes

OBJECTIVE

The prevalence of treatment resistant hypertension (RH) depends on methods used for blood pressure (BP) measurements, goals of BP, and therapeutic efforts in terms of medication and adherence. We focused on diabetic subjects and explored the prevalence of RH in primary care practice.

METHODS

In 1737 subjects with type 2 diabetes who continued regular visits, office BP was evaluated by multiple measurements over one year. RH was defined as using more than four antihypertensive drugs or failure to achieve the goal with three antihypertensive drugs from different classes. The RH prevalence was investigated with BP goals <130/80 and 140/90 mmHg.

RESULTS

The percentage of subjects who achieved BP goals <130/80 and 140/90 were 70.5% and 93.8% with adherence to medication ≥95%, and the corresponding prevalence rates of RH in treated subjects were 28.4% and 21.8%, respectively. Factors independently associated with RH were age (odds ratio 1.02 [95% CI 1.01-1.04]), body mass index (1.10 [1.06-1.13]), variability in systolic BP (1.06 [1.02-1.09]), triglycerides (2.86 [1.34-6.11]), macroalbuminuria (3.33 [2.03-5.48]), estimated glomerular filtration rate (0.98 [0.97-0.99]), retinopathy (1.91 [1.39-2.61]), and family history of hypertension (1.85 [1.23-2.21]). Worsening albuminuria and glomerular filtration rate enhanced the prevalence of RH in a graded manner.

CONCLUSION

Careful estimation of office BP values over one year with a high achievement of BP goals and adequate adherence revealed that the prevalence of RH in type 2 diabetes is high. RH was characterized by accumulation of cardiovascular genetic and environmental risks.

Clinical Significance of Arterial Stiffness and Thickness Biomarkers in Type 2 Diabetes Mellitus: An Up-To-Date Meta-Analysis

Background

Type 2 Diabetes mellitus (T2DM) is associated with increased risk of cardiovascular disease (CVD). Previous studies explored the association of T2DM with arterial stiffness and thickness biomarkers including the augmentation index (AIX), aortic pulse wave velocity (aPWV), brachial-ankle PWV (baPWV), carotid intima-media wall thickness (IMT) as well as blood pressure (BP), low density lipoprotein cholesterol (LDL-C); however the conclusions are either inconsistent or incomprehensive.

Material/Methods

The average differences of each included trial were expressed as the standardized mean difference (SMD) with 95% confidence interval (CI). Analyses of carotid IMT, aPWV, baPWV and AIX Systolic BP (SBP), diastolic BP (DBP), LDL-C and HDL-C were independently performed. Furthermore, subgroup analyses by ethnicity (Caucasian or Asian) were conducted. Begg’s and Egger’s tests were performed for potential publication biases detection.

Results

A total of 14 case-control eligible studies with 1222 T2DM patients and 1094 control subjects were included. In the overall analysis, significant associations were observed between the carotid IMT, aPWV, baPWV, LDL-C, HDL-C, SBP, and DBP with T2DM (IMT: p=1.1*10⁻¹²; aPWV: p=1.1*10⁻⁷; baPWV: p=1.8*10⁻³³; LDL-C: p=3.1*10⁻⁸; HDL-C: p=6.1*10⁻¹⁸; SBP: p=3.9*10⁻²¹; DBP: p=4.8*10⁻⁵). No association was detected for AIX (p=0.09). Subgroup analyses indicated that aPWV, baPWV, SBP, LDL-C, and HDL-C were associated with T2DM in both white and Asian populations (p<0.05). The significant associations of IMT, AIX and DBP with T2DM were only observed in the Asian subgroup.

Conclusions

Carotid IMT, aPWV, baPWV, as well as LDL-C, HDL-C, SBP, and DBP but not AIX were useful noninvasive early markers for T2DM vascular dysfunction detection.

Amiloride lowers blood pressure and attenuates urine plasminogen activation in patients with treatment-resistant hypertension

In conditions with albuminuria, plasminogen is aberrantly filtered across the glomerular barrier and activated along the tubular system to plasmin. In the collecting duct, plasmin activates epithelial sodium channels (ENaC) proteolytically. Hyperactivity of ENaC could link microalbuminuria/proteinuria to resistant hypertension. Amiloride, an ENaC inhibitor, inhibits urokinase-type plasminogen activator. We hypothesized that amiloride (1) reduces blood pressure (BP); (2) attenuates plasminogen-to-plasmin activation; and (3) inhibits urine urokinase-type plasminogen activator in patients with resistant hypertension and type 2 diabetes mellitus (T2DM).In an open-label, non-randomized, 8-week intervention study, a cohort (n = 80) of patients with resistant hypertension and T2DM were included. Amiloride (5 mg/d) was added to previous triple antihypertensive treatment (including a diuretic and an inhibitor of the renin-angiotensin-aldosterone system) and increased to 10 mg if BP control was not achieved at 4 weeks. Complete dataset for urine analysis was available in 60 patients. Systolic and diastolic BP measured by ambulatory BP monitoring and office monitoring were significantly reduced. Average daytime BP was reduced by 6.3/3.0 mm Hg. Seven of 80 cases (9%) discontinued amiloride due to hyperkalemia >5.5 mol/L, the most frequent adverse event. Urinary plasmin(ogen) and albumin excretions were significantly reduced after amiloride treatment (P < .0001). Urokinase activity was detectable in macroalbuminuric urine, with a tendency toward reduction in activity after amiloride treatment. Amiloride lowers BP, urine plasminogen excretion and activation, and albumin/creatinine ratio, and is a relevant add-on medication for the treatment of resistant hypertension in patients with T2DM and microalbuminuria.

Novel effective drugs for diabetic kidney disease? or not?

INTRODUCTION

Diabetes mellitus is increasingly common worldwide and is expected to affect 592 million people by 2035. The kidney is often involved. A key goal in treating diabetes is to reduce the risk of development of kidney disease and, if kidney disease is already present, to delay the progression to end-stage renal disease (ESRD). This represents a social and ethical issue, as a significant proportion of patients reaching ESRD in developing countries do not have access to renal replacement therapy.

AREAS COVERED

The present review focuses on novel therapeutic approaches for diabetic nephropathy (DN), implemented on the basis of recent insights on its pathophysiology, which might complement the effects of single inhibition of the renin-angiotensin-aldosterone system (RAAS), the cornerstone of renoprotective interventions in diabetes, along with glycemic and blood pressure control.

EXPERT OPINION

Although a plethora of new treatment options has arisen from experimental studies, the number of novel renoprotective molecules successfully implemented in clinical practice over the last two decades is disappointingly low. Thus, new investigational strategies and diagnostic tools - including the appropriate choice of relevant renal end points and the study of urinary proteome of patients - will be as important as new therapeutic interventions to fight DN. Finally, in spite of huge financial interests in replacing the less expensive ACE inhibitors and angiotensin II receptor blockers with newer drugs, any future therapeutic approach has to be tested on top of - rather than instead of - optimal RAAS blockade.

Low dose spironolactone reduces blood pressure in patients with resistant hypertension and type 2 diabetes mellitus: a double blind randomized clinical trial

BACKGROUND

The increased risk of cardiovascular morbidity and mortality associated with arterial hypertension is particularly pronounced in patients with type 2 diabetes mellitus. Blood pressure control is, therefore, decisively important but often not sufficiently achieved.

OBJECTIVE

The primary objective of this study was to evaluate the antihypertensive effect of low dose spironolactone added to triple therapy for resistant hypertension in patients with type 2 diabetes measured by ambulatory monitoring. Secondary objectives were to evaluate the effects on glycaemic control and urinary albumin excretion as well as adverse effects.

METHODS

In a multicentre, double-blind, randomized, placebo-controlled study 119 patients with blood pressure at or above 130/80 mmHg despite triple antihypertensive therapy were included. One tablet of 25 mg spironolactone or placebo was added to previous treatment and increased to two if blood pressure below 130/80 mmHg was not achieved after 4 weeks. Blood pressure was measured by ambulatory monitoring at baseline and after 16 weeks.

RESULTS

The study was completed by 112 patients, 57 randomized to spironolactone and 55 to placebo. Average daytime placebo-corrected blood pressure was reduced by 8.9 (4.7-13.2)/3.7 (1.5-5.8) mmHg. Also office blood pressure, night-time, 24-h and pulse pressures were reduced significantly. Urinary albumin/creatinine ratio was significantly reduced in the spironolactone group. Glycaemic control remained unchanged. Hyperkalemia was the most frequent adverse event leading to dose reduction in three cases and discontinuation in one, whereas gynaecomastia was not reported.

CONCLUSION

Low dose spironolactone exerts significant BP and urinary albumin creatinine ratio lowering effects in high-risk patients with resistant hypertension and type 2 diabetes mellitus.

Hypertension after kidney transplantation: a pathophysiologic approach

Post-transplant hypertension is associated with decreased graft and patient survival and cardiovascular morbidity. Unfortunately, post-transplant hypertension is often poorly controlled. Important risk factors include immunosuppressive medications, complications of the transplant surgery, delayed graft function, rejection, and donor and recipient risk factors. The effects of immunosuppressive medications are multifactorial including increased vascular and sympathetic tone and salt and fluid retention. The immunosuppressive agents most commonly associated with hypertension are glucocorticoids and calcineurin inhibitors. Drug therapy for hypertension should be based on the comorbidities and pathophysiology. Evidence-based approaches to defining and treating hypertension in renal transplant recipients are predominantly extrapolated from large-scale studies performed in the general population. Thus, there continues to be a need for larger studies examining the pathophysiology, diagnosis and treatment of hypertension in renal transplant recipients.

Intensive blood pressure control in obese diabetic patients: clinical relevance of stroke prevention in the ACCORD trial

In the ACCORD clinical trial, lowering blood pressure (BP) to normal levels, below currently recommended levels, did not significantly reduce the combined risk of fatal or nonfatal cardiovascular (CV) disease events in adults with Type 2 diabetes. A new post hoc analysis of the same trial also suggests that lowering BP in centrally obese diabetic patients is not a useful means for CV prevention. The authors discuss these findings in the light of accumulated evidence on the relationship between the degree of BP reduction and the risk of CV events in patients with diabetes. In particular, the authors focus on trial and systematic review findings, suggesting that a more intensive reduction of BP in Type 2 diabetes effectively protects from stroke.

Low Diastolic Blood Pressure as a Risk for All-Cause Mortality in VA Patients

Background. A paradoxical increase in cardiovascular events has been reported with intensively lowering diastolic blood pressure (DBP). This J-curve phenomenon has challenged the aggressive lowering of blood pressure, especially in patients with coronary artery disease. Objective. Our objective was to study the effects of low DBP on mortality and determine a threshold for which DBP should not be lowered beyond. Methods. We evaluated a two-year cross-section of primary care veteran patients, from 45 to 85 years of age. Receiver operating characteristics (ROC) were employed to establish an optimal cut-off point for DBP. Propensity-score matching and multivariate logistic regression were used to control for confounders. All-cause mortality was the primary outcome. Results. 14,270 patients were studied. An ROC curve found a threshold value of DBP 70 mmHg had the greatest association with mortality (P < 0.001). 49% of patients had a DBP of 70 mmHg or less. Using a propensity-matched multivariate logistic regression, odds ratio for all-cause mortality in subjects with a DBP less than 70 mmHg was 1.5 (95% CI 1.3-1.8). Conclusions. Reduction of DBP below 70 mmHg is associated with increased all-cause mortality. Hypertension guidelines should include a minimum blood pressure target.

Masked hypertension in diabetes mellitus: treatment implications for clinical practice

Although distinguishing features of masked hypertension in diabetics are well known, the significance of antihypertensive treatment on clinical practice decisions has not been fully explored. We analyzed 9691 subjects from the population-based 11-country International Database on Ambulatory Blood Pressure in Relation to Cardiovascular Outcomes. Prevalence of masked hypertension in untreated normotensive participants was higher (P<0.0001) among 229 diabetics (29.3%, n=67) than among 5486 nondiabetics (18.8%, n=1031). Over a median of 11.0 years of follow-up, the adjusted risk for a composite cardiovascular end point in untreated diabetic-masked hypertensives tended to be higher than in normotensives (hazard rate [HR], 1.96; 95% confidence interval [CI], 0.97-3.97; P=0.059), similar to untreated stage 1 hypertensives (HR, 1.07; CI, 0.58-1.98; P=0.82), but less than stage 2 hypertensives (HR, 0.53; CI, 0.29-0.99; P=0.048). In contrast, cardiovascular risk was not significantly different in antihypertensive-treated diabetic-masked hypertensives, as compared with the normotensive comparator group (HR, 1.13; CI, 0.54-2.35; P=0.75), stage 1 hypertensives (HR, 0.91; CI, 0.49-1.69; P=0.76), and stage 2 hypertensives (HR, 0.65; CI, 0.35-1.20; P=0.17). In the untreated diabetic-masked hypertensive population, mean conventional systolic/diastolic blood pressure was 129.2 ± 8.0/76.0 ± 7.3 mm Hg, and mean daytime systolic/diastolic blood pressure 141.5 ± 9.1/83.7 ± 6.5 mm Hg. In conclusion, masked hypertension occurred in 29% of untreated diabetics, had comparable cardiovascular risk as stage 1 hypertension, and would require considerable reduction in conventional blood pressure to reach daytime ambulatory treatment goal. Importantly, many hypertensive diabetics when receiving antihypertensive therapy can present with normalized conventional and elevated ambulatory blood pressure that mimics masked hypertension.

Blood pressure j-curve: current concepts

The blood pressure (BP) J-curve debate started in 1979, and we still cannot definitively answer all the questions. However, available studies of antihypertensive treatment provide strong evidence for J-shaped relationships between both diastolic and systolic BP and main outcomes in the general population of hypertensive patients, as well as in high-risk populations, including subjects with coronary artery disease, diabetes mellitus, left ventricular hypertrophy, and elderly patients. However, further studies are still necessary in order to clarify this issue. This is connected to the fact that most available studies were observational, and randomized trials did not have or lost their statistical power and were inconclusive. Perhaps only the Systolic Blood Pressure Intervention Trial (SPRINT) and Optimal Blood Pressure and Cholesterol Targets for Preventing Recurrent Stroke in Hypertensives (ESH-CHL-SHOT) will be able to finally answer all the questions. According to the current state of knowledge, it seems reasonable to suggest lowering BP to values within the 130-139/80-85 mmHg range, possibly close to the lower values in this range, in all hypertensive patients and to be very careful with further BP level reductions, especially in high-risk hypertensive patients.

Genetic predisposition to high blood pressure associates with cardiovascular complications among patients with type 2 diabetes: two independent studies

Hypertension and type 2 diabetes (T2D) commonly coexist, and both conditions are major risk factors for cardiovascular disease (CVD). We aimed to examine the association between genetic predisposition to high blood pressure and risk of CVD in individuals with T2D. The current study included 1,005 men and 1,299 women with T2D from the Health Professionals Follow-up Study and Nurses' Health Study, of whom 732 developed CVD. A genetic predisposition score was calculated on the basis of 29 established blood pressure-associated variants. The genetic predisposition score showed consistent associations with risk of CVD in men and women. In the combined results, each additional blood pressure-increasing allele was associated with a 6% increased risk of CVD (odds ratio [OR] 1.06 [95% CI 1.03-1.10]). The OR was 1.62 (1.22-2.14) for risk of CVD comparing the extreme quartiles of the genetic predisposition score. The genetic association for CVD risk was significantly stronger in patients with T2D than that estimated in the general populations by a meta-analysis (OR per SD of genetic score 1.22 [95% CI 1.10-1.35] vs. 1.10 [1.08-1.12]; I² = 71%). Our data indicate that genetic predisposition to high blood pressure is associated with an increased risk of CVD in individuals with T2D.