Blood pressure lowering in patients with diabetes--one level might not fit all

Decision tree-based modelling for identification of potential interactions between type 2 diabetes risk factors: a decade follow-up in a Middle East prospective cohort study

OBJECTIVE

The current study was undertaken for use of the decision tree (DT) method for development of different prediction models for incidence of type 2 diabetes (T2D) and for exploring interactions between predictor variables in those models.

DESIGN

Prospective cohort study.

SETTING

Tehran Lipid and Glucose Study (TLGS).

METHODS

A total of 6647 participants (43.4% men) aged >20 years, without T2D at baselines ((1999-2001) and (2002-2005)), were followed until 2012. 2 series of models (with and without 2-hour postchallenge plasma glucose (2h-PCPG)) were developed using 3 types of DT algorithms. The performances of the models were assessed using sensitivity, specificity, area under the ROC curve (AUC), geometric mean (G-Mean) and F-Measure.

PRIMARY OUTCOME MEASURE

T2D was primary outcome which defined if fasting plasma glucose (FPG) was ≥7 mmol/L or if the 2h-PCPG was ≥11.1 mmol/L or if the participant was taking antidiabetic medication.

RESULTS

During a median follow-up of 9.5 years, 729 new cases of T2D were identified. The Quick Unbiased Efficient Statistical Tree (QUEST) algorithm had the highest sensitivity and G-Mean among all the models for men and women. The models that included 2h-PCPG had sensitivity and G-Mean of (78% and 0.75%) and (78% and 0.78%) for men and women, respectively. Both models achieved good discrimination power with AUC above 0.78. FPG, 2h-PCPG, waist-to-height ratio (WHtR) and mean arterial blood pressure (MAP) were the most important factors to incidence of T2D in both genders. Among men, those with an FPG≤4.9 mmol/L and 2h-PCPG≤7.7 mmol/L had the lowest risk, and those with an FPG>5.3 mmol/L and 2h-PCPG>4.4 mmol/L had the highest risk for T2D incidence. In women, those with an FPG≤5.2 mmol/L and WHtR≤0.55 had the lowest risk, and those with an FPG>5.2 mmol/L and WHtR>0.56 had the highest risk for T2D incidence.

CONCLUSIONS

Our study emphasises the utility of DT for exploring interactions between predictor variables.

Resistant hypertension in patients with type 2 diabetes: clinical correlates and association with complications

OBJECTIVE

The phenotype of resistant hypertension in patients with type 2 diabetes has been poorly characterized. This cross-sectional analysis of the large cohort from the Renal Insufficiency and Cardiovascular Events (RIACE) study was aimed at assessing the clinical correlates and association with complications of resistant hypertension in patients with type 2 diabetes.

METHODS

The RIACE study enrolled 15,773 patients consecutively visiting 19 diabetes clinics during the years 2007-2008. Resistant hypertension, defined as BP values not on target (i.e. >130/80 mmHg, respectively) with three antihypertensive agents, was detected in 2363 individuals (15% of the whole RIACE cohort, 17.4% of hypertensive individuals, and 21.2% of treated hypertensive patients). Patients without resistant hypertension [nonresistant hypertension (NRH)], that is on target with one (n = 1569), two (n = 1369), and three (n = 803) drugs, and individuals with uncontrolled hypertension, that is untreated or not on target with less than three drugs (n = 7440), served as controls.

RESULTS

As compared with NRH and uncontrolled hypertension patients, patients with resistant hypertension were older and more frequently women and had significantly higher waist circumference, albuminuria, and serum creatinine, and lower glomerular filtration rate. Prevalence values of chronic kidney disease and advanced retinopathy were significantly higher in resistant hypertension than in both nonresistant hypertension and uncontrolled hypertension individuals, whereas cardiovascular disease was more frequent in resistant hypertension versus uncontrolled hypertension, but not nonresistant hypertension patients, especially those on 2-3 drugs.

CONCLUSIONS

Resistant hypertension is relatively common in patients with type 2 diabetes. In these individuals, age, female sex and waist circumference are independent correlates of resistant hypertension, which is strongly associated with microvascular (especially renal) disease, whereas relation with macrovascular complications is unclear.

Prognostic impact of clinic and ambulatory blood pressure components in high-risk type 2 diabetic patients: the Rio de Janeiro Type 2 Diabetes Cohort Study

BACKGROUND

The prognostic importance of tight clinic blood pressure (BP) control is controversial in diabetic patients. The objective was to investigate the prognostic impact of clinic and ambulatory BPs for cardiovascular morbidity and mortality in type 2 diabetes.

METHODS

In a prospective cohort study, 565 type 2 diabetic patients had clinical, laboratory and ambulatory BP monitoring (ABPM) data obtained at baseline and during follow-up. The primary endpoints were a composite of fatal and nonfatal cardiovascular events and all-cause mortality. Multivariable Cox survival and splines regression analyses assessed associations between each BP component [SBP, DBP and pulse pressure (PP)] and the endpoints.

RESULTS

After a median follow-up of 5.75 years, 88 total cardiovascular events and 70 all-cause deaths occurred. After adjustments for cardiovascular risk factors, clinic SBP and DBPs were predictive of the composite endpoint but not of all-cause mortality, whereas all ambulatory BP components were predictors of both endpoints. Ambulatory systolic and PPs were the strongest predictors and achieved ambulatory BPs during follow-up improved risk prediction in relation to baseline values. When categorized at clinically relevant cut-off values, risk began only at clinic BPs at least 140/90 mmHg, whereas for ambulatory BPs it began at lower values (≥120/75 mmHg for the 24-h period).

CONCLUSION

ABPM provides more valuable information regarding cardiovascular risk stratification than office BPs and should be performed, if possible, in every high-risk type 2 diabetic patient. Achieved 24-h ambulatory BPs less than 120/75 mmHg are associated with significant cardiovascular protection and, if confirmed by other studies, may be considered as BP treatment targets.

The goal of blood pressure in the hypertensive patient with diabetes is defined: now the challenge is go from recommendations to practice

The recent Latin American and European guidelines published this year has proposed as a goal for blood pressure control in patients with diabetes type 2 a value similar or inferior to 140/90 mmHg. High blood pressure is the leading cause of cardiovascular diseases and deaths globally. Although once hypertension is detected, 80% of individuals are on a pharmacologic therapy only a minority is controlled. Diabetes also is a risk factor for other serious chronic diseases, including cardiovascular disease. Whether specifically targeting lower fasting glucose levels can reduce cardiovascular outcomes remains unknown. Hypertension is present in 20% to 60% of patients with type 2 diabetes, depending on age, ethnicity, obesity, and the presence of micro or macro albuminuria. High blood pressure substantially increases the risk of both macro and micro vascular complications, doubling the risk of all-cause mortality and stroke, tripling the risk of coronary heart disease and significantly hastening the progression of diabetic nephropathy, retinopathy, and neuropathy. Thus, blood pressure lowering is a major priority in preventing cardiovascular and renal events in patients with diabetes and hypertension. During many years the BP goals recommended in patients with diabetes were more aggressive than in patients without diabetes. As reviewed in this article many clinical trials have demonstrated not only the lack of benefits of lowering the BP below 130/80 mmHg, but also the J-shaped relationship in DM patients. Overall we discuss the importance of define the group of patients in whom significant BP reduction could be particularly dangerous and, on the other hand, those with a high risk of stroke who could benefit most from an intensive hypotensive therapy. In any case, the big challenge now is avoid the therapeutic inertia (leaving diabetic patients with BP values of 140/90 mmHg or higher) at all costs, as this would lead to an unacceptable toll in terms of human lives, suffering, and socioeconomic costs.

Which is a better treatment for hypertensive patients with diabetes: a combination of losartan and hydrochlorothiazide or a maximum dose of losartan?

BACKGROUND

This 12-month study compared the effects of a combination of losartan 50 mg and hydrochlorothiazide 12.5 mg with a maximum dose of losartan (100 mg) in hypertensive patients with diabetes.

METHODS

This was a multicenter randomized open-label study.

RESULTS

A similar reduction in systolic/diastolic blood pressure from baseline to month 3 was observed in both groups. There was also a similar decrease in UACR in both groups. A significant decrease in uric acid was observed in the maximum-dose group only. eGFR decreased in the combination group after 1 year.

CONCLUSIONS

The combination of losartan and a diuretic may be a useful option in such hypertensive patients with diabetes, provided that metabolic parameters are closely monitored. In patients with hyperuricemia and impaired renal function, a maximum dose of losartan may be more beneficial.

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.

Monitoring performance for blood pressure management among patients with diabetes mellitus: too much of a good thing?

BACKGROUND

Performance measures that reward achieving blood pressure (BP) thresholds may contribute to overtreatment. We developed a tightly linked clinical action measure designed to encourage appropriate medical management and a marker of potential overtreatment, designed to monitor overly aggressive treatment of hypertension in the face of low diastolic BP.

METHODS

We conducted a retrospective cohort study in 879 Department of Veterans Affairs (VA) medical centers and smaller community-based outpatient clinics. The clinical action measure for hypertension was met if the patient had a passing index BP at the visit or had an appropriate action. We examined the rate of passing the action measure and of potential overtreatment in the Veterans Health Administration during 2009-2010.

RESULTS

There were 977,282 established VA patients, 18 years and older, with diabetes mellitus (DM). A total of 713,790 patients were eligible for the action measure; 94% passed the measure (82% because they had a BP <140/90 mm Hg at the visit and an additional 12% with a BP ≥140/90 mm Hg and appropriate clinical actions). Facility pass rates varied from 77% to 99% (P < .001). Among all patients with DM, 197,291 (20%) had a BP lower than 130/65 mm Hg; of these, 80 903 (8% of all patients with DM) had potential overtreatment. Facility rates of potential overtreatment varied from 3% to 20% (P < .001). Facilities with higher rates of meeting the current threshold measure (<140/90 mm Hg) had higher rates of potential overtreatment (P < .001).

CONCLUSIONS

While 94% of diabetic veterans met the action measure, rates of potential overtreatment are currently approaching the rate of undertreatment, and high rates of achieving current threshold measures are directly associated with overtreatment. Implementing a clinical action measure for hypertension management, as the Veterans Health Administration is planning to do, may result in more appropriate care and less overtreatment.

Single-pill combination of telmisartan/amlodipine versus amlodipine monotherapy in diabetic hypertensive patients: an 8-week randomized, parallel-group, double-blind trial

BACKGROUND

Hypertensive patients with diabetes often require combination therapy to achieve a blood pressure (BP) goal, and evidence suggests that time to BP goal is crucial to decrease cardiovascular risk.

OBJECTIVE

The aim of the study was to investigate whether the single-pill combination of telmisartan and amlodipine was superior to amlodipine alone as initial antihypertensive therapy in patients with diabetes and hypertension.

METHODS

An 8-week, randomized, parallel-group, double-blind international trial comparing the once-daily single-pill combination of telmisartan 80 mg and amlodipine 10 mg (T/A; n = 352) with once-daily amlodipine 10 mg (A; n = 354) in patients with type 2 diabetes mellitus and stage 1 or 2 hypertension (systolic BP [SBP] >150 mm Hg).

RESULTS

Patient demographics were similar between treatment groups, with an mean (SD) age of 60.5 (10.1) years; 51.7% were male, the mean (SD) body mass index was 32.0 (6.1) and the mean (SD) duration of hypertension was 8.8 (7.9) years. After 8 weeks (primary end point) as well as after 1, 2, and 4 weeks (key secondary end points), significantly greater decreases in the in-clinic mean seated trough cuff SBP with T/A versus A were achieved (-29.0 mm Hg vs -22.9 mm Hg at 8 weeks; P < 0.0001). After 8 weeks, 71.4% versus 53.8% of patients achieved the BP goal (<140/90 mm Hg) with T/A versus A, with mean SBPs of 131.9 and 137.9 mm Hg, respectively. Similar results were observed in the obese (metabolic syndrome) subpopulation. The more stringent goal (<130/80 mm Hg) was achieved by 36.4% and 17.9% patients in the T/A and A groups, respectively. The most common adverse events were peripheral edema, headache, and dizziness.

CONCLUSIONS

In this selected population of patients with diabetes and hypertension, T/A provided prompt and greater BP decreases compared with A monotherapy, with the majority of patients achieving the BP goal (<140/90 mm Hg).

How to stay heart healthy in 2011: considerations for the primary prevention of cardiovascular disease in women

More women die of cardiovascular disease than any other cause. Effective primary prevention depends on accurate assessment of risk status. While most risk factors are similar for men and women, risk factors may differ in magnitude between the sexes, and recognition of gender-specific risk factors such as gestational diabetes, hypertensive syndromes of pregnancy and polycystic ovarian syndrome provides opportunities for early intervention and prevention. Obesity, hypertension and hyperlipidemia affect both genders; however, women often postpone addressing these risk factors until later in life. The American Heart Association emphasizes that all women are at cardiovascular risk and should maintain a healthy lifestyle and avoid smoking. Blood pressure, hyperlipidemia and diabetes should be aggressively treated. Current available data regarding proposed preventive drug therapies including daily aspirin, HRT, vitamin D and omega-3 fatty acid supplements will be reviewed.

What should be the optimal levels of blood pressure: Does the J-curve phenomenon really exist?

INTRODUCTION

The blood pressure (BP) J-curve debate has lasted for over 30 years and we still cannot definitively answer all the questions. However, recent studies suggest that BP should be reduced carefully in patients with hypertension and coronary artery disease. BP should not fall below 110 - 115/70 - 75 mmHg, because this may be associated with more cardiovascular events.

AREAS COVERED

A retrospective analysis of the INVEST Trial and the results of the BP arm of the ACCORD Trial shows that care is needed in patients with hypertension and diabetes. Although the ACCORD BP Trial suggests important benefits connected with the significant reduction of stroke in patients being treated intensively, it also shows the lack of advantage of such therapy on each main and other additional endpoints. The ACCORD Trial also confirmed the increased risk of adverse events that might appear when intensive treatment was used in this group of patients.

EXPERT OPINION

Most available studies were observational and randomized trials (BBB, HOT, ACCORD BP), do not have or have lost their statistical power and were inconclusive. Further studies are therefore needed to provide definitive conclusions on the subject. In the meantime, it seems that in high-risk patients with hypertension, it is necessary to carefully select those who might suffer adverse events and those who may benefit from intensive BP lowering.

Drug of choice in the management of hypertension in diabetes and diabetic nephropathy: angiotensin-converting enzyme inhibitors

Hypertension is common in patients with diabetes mellitus and is a main cause of renal and cardiovascular complications. There has been recent controversy on what should be considered the optimal blood pressure goal and the optimal antihypertensive agent. It has become apparent that one blood pressure does not fit all in diabetic patients. Major confounders are preexisting cardiovascular disease and presence or absence of proteinuric kidney disease. In proteinuric diabetic nephropathy, renin-angiotensin system blockade is clearly indicated, but monotherapy is practically always insufficient to achieve target blood pressure values.