Blood pressure lowering and major cardiovascular events in people with and without chronic kidney disease: meta-analysis of randomised controlled trials

OBJECTIVE

To define the cardiovascular effects of lowering blood pressure in people with chronic kidney disease.

DESIGN

Collaborative prospective meta-analysis of randomised trials.

DATA SOURCES AND ELIGIBILITY

Participating randomised trials of drugs to lower blood pressure compared with placebo or each other or that compare different blood pressure targets, with at least 1000 patient years of follow-up per arm.

MAIN OUTCOME MEASURES

Major cardiovascular events (stroke, myocardial infarction, heart failure, or cardiovascular death) in composite and individually and all cause death.

PARTICIPANTS

26 trials (152,290 participants), including 30,295 individuals with reduced estimated glomerular filtration rate (eGFR), which was defined as eGFR <60 mL/min/1.73 m(2).

DATA EXTRACTION

Individual participant data were available for 23 trials, with summary data from another three. Meta-analysis according to baseline kidney function was performed. Pooled hazard ratios per 5 mm Hg lower blood pressure were estimated with a random effects model.

RESULTS

Compared with placebo, blood pressure lowering regimens reduced the risk of major cardiovascular events by about a sixth per 5 mm Hg reduction in systolic blood pressure in individuals with (hazard ratio 0.83, 95% confidence interval 0.76 to 0.90) and without reduced eGFR (0.83, 0.79 to 0.88), with no evidence for any difference in effect (P=1.00 for homogeneity). The results were similar irrespective of whether blood pressure was reduced by regimens based on angiotensin converting enzyme inhibitors, calcium antagonists, or diuretics/β blockers. There was no evidence that the effects of different drug classes on major cardiovascular events varied between patients with different eGFR (all P>0.60 for homogeneity).

CONCLUSIONS

Blood pressure lowering is an effective strategy for preventing cardiovascular events among people with moderately reduced eGFR. There is little evidence from these overviews to support the preferential choice of particular drug classes for the prevention of cardiovascular events in chronic kidney disease.

The effects of patient characteristics and geographical region on hospitalization in patients with type 2 diabetes

AIMS

The ADVANCE trial recruited participants from 20 countries worldwide. We analyse here regional variations and causes of hospitalization for people with Type 2 diabetes from Asia, Established Market Economies and Eastern Europe.

METHODS

A cohort analysis examining the effects of region on causes of first hospitalization, and the association of participant characteristics on all-cause first hospitalization across regions, using multivariable (adjusted for clinical, physiological, behavioural and socio-demographic factors) Cox models.

RESULTS

Of 11 140 individuals (6407 men), all-cause hospitalization rates were highest in Established Market Economies, followed by Eastern Europe then Asia. Eastern Europe had rates of hospitalization for diabetic causes four times greater than Established Market Economies [multivariable-adjusted hazard ratio 4.02 (95% CI 2.86-5.63)]. There were no significant regional variations in hospitalization rates for cardiovascular disease (P = 0.534), but much lower rates for musculoskeletal and non-specific causes in Eastern Europe [multivariable-adjusted hazard ratio 0.44 (95% CI 0.32-0.60) and 0.19 (95% CI 0.12-0.29)] and Asia [hazard ratio 0.21 (95% CI 0.16-0.29) and 0.09 (95% CI 0.06-0.14)] compared with Established Market Economies. In all regions, participants hospitalized for any cause were more likely to be older, male, hypertensive, smokers, have higher glycated haemoglobin and a history of macrovascular or macrovascular disease.

CONCLUSIONS

Across three markedly different regions of the world, regional rates and causes of hospitalization varied widely in patients with Type 2 diabetes. Adjustment for a range of patient characteristics did not explain these regional differences in hospitalization, which appear to be attributable to health system factors.

Predicting a post-thrombolysis intracerebral hemorrhage: a systematic review

OBJECTIVES

Fear of an intracerebral hemorrhage (ICH) is a deterrent to the uptake of thrombolytic therapy, an evidence-based treatment for an acute ischemic stroke. Several characteristics associated with post-thrombolysis ICH have been identified, but their combined utility for risk stratification has yet to be clarified. We critically examined risk models to predict post-thrombolysis ICH, and evaluated their potential clinical utility.

METHODS

MEDLINE and EMBASE (Inception to October 2012) were searched and bibliographies of retrieved articles examined. Inclusion and exclusion criteria of each study were reviewed. Eligible studies had to report on the development, validation or impact assessment of a model constructed to predict the occurrence of ICH after thrombolysis for an ischemic stroke.

RESULTS

We identified 10 publications reporting on 13 post-thrombolysis ICH risk models, each developed from logistic regression. The number of participants/outcomes/predictors per model ranged from 89/45/4 to 27 804/558/7; age, glycemia and the NIH stroke scale score were common predictors. Models had modest-to-acceptable discriminatory ability (c-statistic ranging from 0.59 to 0.88) in the derivation sample and during external validation (conducted for three models). Calibration was acceptable in the three studies where it was assessed. Impact studies to evaluate the effect of adopting ICH risk models on clinical outcomes have not yet been conducted.

CONCLUSIONS

The development and clinical application of ICH risk scores remains a developing field. Extensive external validation and impact studies are needed to strengthen evidence regarding their utility for improving the selection of ischemic stroke victims for thrombolysis while mitigating risks of complications through post-thrombolysis ICH.

Sleep, blood pressure and obesity in 22,389 New Zealanders

AIM

To determine the relationship of sleep disorders with blood pressure and obesity in a large, relatively healthy, community-based cohort.

METHODS

A cross-sectional study was undertaken using data from 22,389 volunteer blood donors in New Zealand aged 16-84 years. Height, weight, neck circumference and blood pressure were measured directly, and data on sleep and other factors were ascertained using a validated self-administered questionnaire.

RESULTS

Even in a relatively young, non-clinical cohort, lack of sleep (34%), snoring (33%), high blood pressure (20%) and obesity (19%) are common. After adjusting for relevant confounders, participants at high risk of sleep apnoea had double the odds of having high blood pressure but only in participants over 40 years. Very low and high quantities of sleep are also associated with high blood pressure. Even after controlling for neck circumference, self-reported sleep apnoea, sleep dissatisfaction and low amounts of sleep are associated with a higher body mass index.

CONCLUSIONS

Obesity and hypertension have significant associations with a variety of sleep disorders, even in those less than 40 years of age and after adjusting for a wide range of potential confounders.

Managing chronic inflammation in the aging diabetic patient with CKD by diet or sevelamer carbonate: a modern paradigm shift

The maintenance of normal metabolism and body defenses depends on the balance between cellular antioxidant and anti-inflammatory factors. This balance can be disrupted by agents/mechanisms in the extracellular milieu that induce excess reactive oxygen species (ROS) and inflammation. Cytopathic advanced glycation endproducts, present in ever increasing amounts in the modern diet, are one of the major environmental factors that cause excess ROS and/or inflammation at all ages and induce complications in aging, such as chronic kidney disease (CKD) and type 2 diabetes. Increased ROS and/or inflammation are present in both aging and CKD, and are associated with reduced cellular defenses against ROS and/or inflammation. Affected individuals have reduced defenses against further stress and are predisposed to organ failure, now a well-known phenomenon in aging. Thus, new methods are urgently needed to safely reduce ROS and/or inflammation in the aging type 2 diabetes patient with CKD. Studies of both normal aging and diabetic patients with kidney disease underline the fact that increased ROS and/or inflammation can be managed in these conditions by economical, safe, and effective interventions that reduce the uptake of advanced glycation endproducts by either modifying preparation of food or an oral drug. This communication reviews these data and adds new information on the efficacy of a drug, sevelamer carbonate, required to reduce ROS and/or inflammation in the aging type 2 diabetes patient complicated by CKD. If larger and longer studies confirm the hypothesis that one or both of these interventions reduce progression of CKD, it could represent a new paradigm in the management of complications in the type 2 diabetes patient with CKD.

Outcome of the Lima periurethral constrictor in children and adolescents: a European perspective

PURPOSE

The Lima constrictor was described in 1996 as a less complex and less expensive alternative to the artificial urinary sphincter for use in cases of pediatric neuropathic sphincter incontinence. The device provides a fixed periurethral resistance which creates continence, yet allows urethral catheterization without the need to deflate the cuff. We report our multicenter experience, and continence, revision and erosion rates.

MATERIALS AND METHODS

We performed a retrospective review of 14 consecutive patients who underwent insertion of the periurethral constrictor (Silimed, Rio de Janeiro, Brazil) between 2005 and 2011. Data are presented as medians (range).

RESULTS

A total of 14 patients (13 male, 1 female) with spina bifida (10), sacral agenesis (3) and Hirschsprung disease (1) underwent insertion of the constrictor at a median age of 12 years (range 8 to 20). All patients were wet despite clean intermittent catheterization, medical therapy and/or previous surgery. Eleven patients underwent simultaneous bladder augmentation and/or Mitrofanoff formation. The constrictor was activated a median of 8 weeks (range 2 to 99) after the procedure in 11 patients whereas 3 became dry without activation. Complications occurred in 4 patients (29%), including spontaneous bladder perforation and constrictor erosion (1), tubing disconnection requiring revision (2) and wound infection (1). At a median of 23 months of followup (range 7 to 77) 13 patients were dry and 1 was damp. All patients performed urethral or Mitrofanoff clean intermittent catheterization. The continence rate with the device in situ was 92%.

CONCLUSIONS

At a median followup of 23 months the Lima constrictor provided a 92% continence rate with erosion and revision rates of 7% and 14%, respectively. Interim results suggest that the constrictor provides a safe and effective surgical option, particularly in patients who are unable to void to completion.

TU-G-211-01: New Member Symposium

As a new member of the AAPM, it's easy to feel overwhelmed by the size and complexity of the association and to be unaware of the benefits and opportunities available to members. At this year's AAPM national meeting in Charlotte, we will host a New Member Symposium, where you can learn more about the organization, member resources, opportunities to get involved, and about topics of particular interest to new professionals. We encourage you to take advantage of this great opportunity to learn valuable information and to grow your professional network. Following an introduction from Dr. Gary A. Ezzell, the AAPM President; Michael Woodward of the AAPM staff will provide a crash course on the AAPM structure and organization, as well as some pointers on navigating the website. Next will be Dr. Michael Mills presenting on the current state of the U.S. Medical Physics Workforce, Staffing, Supply & Demand, and Limited Residency slots. Registered attendees will receive a raffle ticket for entry in a drawing to win a complimentary registration for the 2013 Annual Meeting in Indianapolis. In addition, all new members who register for the Symposium will receive a drink ticket good for one complimentary beer served after the New Member Symposium during the social with committee chairs from 4 AAPM Councils: Science, Education, Professional, and Administrative.

Weight changes and their predictors amongst 11 140 patients with type 2 diabetes in the ADVANCE trial

AIMS

To determine the baseline characteristics and glucose-lowering therapies associated with weight change among patients with type 2 diabetes.

METHODS

Eleven thousand one hundred and forty participants in the ADVANCE trial were randomly assigned to an intensive [aiming for a haemoglobin A1c (HbA1c) ≤6.5%] or a standard blood glucose-control strategy. Weight was measured at baseline and every 6 months over a median follow-up of 5 years. Multivariable linear regression and linear-mixed effect models were used to examine predictors of weight change.

RESULTS

The mean difference in weight between the intensive and standard glucose-control arm during follow-up was 0.75 kg (95% CI: 0.56-0.94), p-value <0.001. The mean weight decreased by 0.70 kg (95% CI: 0.53-0.87), p < 0.001 by the end of follow-up in the standard arm but remained stable in the intensive arm, with a non-significant gain of 0.16 kg (95% CI: -0.02 to 0.34), p = 0.075. Baseline factors associated with weight gain were younger age, higher HbA1c, Caucasian ethnicity and number of glucose-lowering medications. Treatment combinations including insulin [3.22 kg (95% CI: 2.92-3.52)] and thiazolidinediones [3.06 kg (95% CI: 2.69-3.43)] were associated with the greatest weight gain while treatment combinations including sulphonylureas were associated with less weight gain [0.71 kg (95%CI: 0.39-1.03)].

CONCLUSIONS

Intensive glucose-control regimens are not necessarily associated with substantial weight gain. Patient characteristic associated with weight change were age, ethnicity, smoking and HbA1c. The main treatment strategies predicting weight gain were the use of insulin and thiazolidinediones.

Resting heart rate and the risk of death and cardiovascular complications in patients with type 2 diabetes mellitus

AIMS/HYPOTHESIS

An association between resting heart rate and mortality has been described in the general population and in patients with cardiovascular disease. There are, however, few data exploring this relationship in patients with type 2 diabetes mellitus. The current study addresses this issue.

METHODS

The relationship between baseline resting heart rate and all-cause mortality, cardiovascular death and major cardiovascular events (cardiovascular death, non-fatal myocardial infarction or non-fatal stroke) was examined in 11,140 patients who participated in the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) Study.

RESULTS

A higher resting heart rate was associated with a significantly increased risk of all-cause mortality (fully adjusted HR 1.15 per 10 bpm [95% CI 1.08, 1.21], p<0.001), cardiovascular death and major cardiovascular outcomes without adjustment and after adjusting for age and sex and multiple covariates. The increased risk associated with a higher baseline resting heart rate was most obvious in patients with previous macrovascular complications (fully adjusted HR for death 1.79 for upper [mean 91 bpm] vs lowest [mean 58 bpm] fifth of resting heart rate in this subgroup [95% CI 1.28, 2.50], p = .001).

CONCLUSIONS/INTERPRETATION

Among patients with type 2 diabetes, a higher resting heart rate is associated with an increased risk of death and cardiovascular complications. It remains unclear whether a higher heart rate directly mediates the increased risk or is a marker for other factors that determine a poor outcome.

Deployment-related TBI, persistent postconcussive symptoms, PTSD, and depression in OEF/OIF veterans

OBJECTIVE

A substantial proportion of the more than 2 million service members who have served in Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF) have experienced a traumatic brain injury (TBI). Understanding the long-term impact of TBI is complicated by the nonspecific nature of postconcussive symptoms (PCSs) and the high rates of co-occurrence among TBI, posttraumatic stress disorder (PTSD), and depression. The goal of the present research was to examine the relations among TBI, persistent PCSs, and symptoms of PTSD and depression among returning OEF/OIF veterans.

METHOD

213 OEF/OIF veterans (87% male) completed a semistructured screening interview assessing deployment-related TBI and current, persistent PCSs. Participants also completed self-report measures of combat exposure and current symptoms of PTSD and depression.

RESULTS

Nearly half (46%) of sampled veterans screened positive for TBI, the majority of whom (85%) reported at least one persistent PCS after removing PCSs that overlapped with PTSD and depression. Veterans with deployment-related TBI reported higher levels of combat exposure and symptoms of PTSD and depression. Structural equation modeling was used to assess the fit of 3 models of the relationships among TBI, combat exposure, persistent PCSs, PTSD, and depression. Consistent with hypotheses, the best-fitting model was one in which the effects of TBI on both PTSD and depression were fully mediated by nonoverlapping persistent PCSs.

CONCLUSIONS

These findings highlight the importance of addressing persistent PCSs in order to facilitate the functional recovery of returning war veterans.

Association of HbA1c levels with vascular complications and death in patients with type 2 diabetes: evidence of glycaemic thresholds

AIMS/HYPOTHESIS

There is conflicting evidence regarding appropriate glycaemic targets for patients with type 2 diabetes. Here, we investigate the relationship between HbA(1c) and the risks of vascular complications and death in such patients.

METHODS

Eleven thousand one hundred and forty patients were randomised to intensive or standard glucose control in the Action in Diabetes and Vascular disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) trial. Glycaemic exposure was assessed as the mean of HbA(1c) measurements during follow-up and prior to the first event. Adjusted risks for each HbA(1c) decile were estimated using Cox models. Possible differences in the association between HbA(1c) and risks at different levels of HbA(1c) were explored using linear spline models.

RESULTS

There was a non-linear relationship between mean HbA(1c) during follow-up and the risks of macrovascular events, microvascular events and death. Within the range of HbA(1c) studied (5.5-10.5%), there was evidence of 'thresholds', such that below HbA(1c) levels of 7.0% for macrovascular events and death, and 6.5% for microvascular events, there was no significant change in risks (all p > 0.8). Above these thresholds, the risks increased significantly: every 1% higher HbA(1c) level was associated with a 38% higher risk of a macrovascular event, a 40% higher risk of a microvascular event and a 38% higher risk of death (all p < 0.0001).

CONCLUSIONS/INTERPRETATION

In patients with type 2 diabetes, HbA(1c) levels were associated with lower risks of macrovascular events and death down to a threshold of 7.0% and microvascular events down to a threshold of 6.5%. There was no evidence of lower risks below these levels but neither was there clear evidence of harm.

Prediction models for the risk of cardiovascular disease in patients with type 2 diabetes: a systematic review

CONTEXT

A recent overview of all CVD models applicable to diabetes patients is not available.

OBJECTIVE

To review the primary prevention studies that focused on the development, validation and impact assessment of a cardiovascular risk model, scores or rules that can be applied to patients with type 2 diabetes.

DESIGN

Systematic review.

DATA SOURCES

Medline was searched from 1966 to 1 April 2011.

STUDY SELECTION

A study was eligible when it described the development, validation or impact assessment of a model that was constructed to predict the occurrence of cardiovascular disease in people with type 2 diabetes, or when the model was designed for use in the general population but included diabetes as a predictor.

DATA EXTRACTION

A standardized form was sued to extract all data of the CVD models.

RESULTS

45 prediction models were identified, of which 12 were specifically developed for patients with type 2 diabetes. Only 31% of the risk scores has been externally validated in a diabetes population, with an area under the curve ranging from 0.61 to 0.86 and 0.59 to 0.80 for models developed in a diabetes population and in the general population, respectively. Only one risk score has been studied for its effect on patient management and outcomes. 10% of the risk scores are advocated in national diabetes guidelines.

CONCLUSION

Many cardiovascular risk scores are available that can be applied to patients with type 2 diabetes. A minority of these risk scores has been validated and tested for its predictive accuracy, with only a few showing a discriminative value of ≥0.80. The impact of applying these risk scores in clinical practice is almost completely unknown, but their use is recommended in various national guidelines.

Oral disease in relation to future risk of dementia and cognitive decline: prospective cohort study based on the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified-Release Controlled Evaluation (ADVANCE) trial

OBJECTIVE

Examine the association of oral disease with future dementia/cognitive decline in a cohort of people with type 2 diabetes.

METHODS

A total of 11,140 men and women aged 55-88 years at study induction with type 2 diabetes participated in a baseline medical examination when they reported the number of natural teeth and days of bleeding gums. Dementia and cognitive decline were ascertained periodically during a 5-year follow-up.

RESULTS

Relative to the group with the greatest number of teeth (more than or equal to 22), having no teeth was associated with the highest risk of both dementia (hazard ratio; 95% confidence interval: 1.48; 1.24, 1.78) and cognitive decline (1.39; 1.21, 1.59). Number of days of bleeding gums was unrelated to these outcomes.

CONCLUSIONS

Tooth loss was associated with an increased risk of both dementia and cognitive decline.

Intensive glucose control and risk of cancer in patients with type 2 diabetes

AIMS/HYPOTHESIS

Type 2 diabetes has been associated with an increased risk of cancer. This study examines the effect of more vs less intensive glucose control on the risk of cancer in patients with type 2 diabetes.

METHODS

All 11,140 participants from the Action in Diabetes and Vascular Disease: Preterax and Diamicron-MR Controlled Evaluation (ADVANCE) trial (ClinicalTrials.gov NCT00145925) were studied. Cancer incidence and cancer mortality was compared in groups randomised to intensive or standard glucose control. Information on events during follow-up was obtained from serious adverse event reports and death certificates. HRs (95% CI) were calculated for all cancers, all solid cancers, cancer deaths and site-specific cancers.

RESULTS

After a median follow-up of 5 years, 363 and 337 cancer events were reported in the intensive and standard control groups, respectively (incidence 1.39/100 person-years [PY] and 1.28/100 PY; HR 1.08 [95% CI 0.93-1.26]). The incidences of all solid cancers and cancer deaths were 1.25/100 PY and 0.55/100 PY in the intensive group and 1.15/100 PY and 0.63/100 PY in the standard group (HR 1.09[95% CI 0.93–1.27] for solid cancers, and 0.88 [0.71–1.10] for cancer death) [corrected].Across all the major organ systems studied, no significant differences in the cancer incidences were observed in the intensive and standard control groups.

CONCLUSIONS/INTERPRETATIONS

More intensive glucose control achieved with a regimen that included greater use of gliclazide, insulin, metformin and other agents, did not affect the risk of cancer events or death in patients with type 2 diabetes.

The burden of cardiovascular disease associated with high body mass index in the Asia-Pacific region

Studying obesity in the Asia-Pacific region is difficult because of the diverse ethnic background and different stages of economic and nutrition transition. The burden of cardiovascular disease associated with overweight (defined as body mass index ≥25 kg m(-2) ) was previously estimated for countries within the region. However, using the conventional cut-point of 25 kg m(-2) ignores the continuous association between body mass index and cardiovascular disease from approximately 20 kg m(-2) . By estimating the proportion of cardiovascular disease that would be prevented if the theoretical mean body mass index in the population was shifted to 21 kg m(-2) , nationally representative data from 15 countries suggested the population attributable fractions for cardiovascular disease were approximately three times higher than the previous estimates. Coronary heart disease attributable to body mass index other than 21 kg m(-2) ranged from 2% in India to 58% in American Samoa. Similarly, the population attributable fraction for ischaemic stroke ranged from 3% in India to 64% in American Samoa. If cardiovascular risk increases from 21 kg m(-2) applies to all populations, most countries in the region will need to aim towards substantially reducing their current population mean body mass index in order to lower the burden of cardiovascular disease associated with excess weight.