The New England Journal of Medicine has published two subgroup analyses of the ACCORD study. The first analysis compares combination lipid lowering therapy to standard care and the second analysis compares intensive blood pressure control to standard care.
In the first analysis, 5,518 patients with type 2 diabetes were treated with open label simvastatin and randomly assigned to blinded treatment with fenofibrate or placebo. The primary outcome was a composite of non-fatal myocardial infarction, non-fatal stroke or death from cardiovascular causes. The study found no statistical differences between the two groups for the primary outcome or for any of the secondary outcome when analysed individually.
The authors conclude that, “these results do not support the routine use of combination therapy with fenofibrate and simvastatin to reduce cardiovascular risk“.
In the second analysis, 4,733 participants were assigned to intensive blood pressure treatment with the aim of reaching a systolic blood pressure target of 120mmHg or less versus standard treatment with a target of 140mmHg or less. Again, the primary outcome was a composite of non-fatal myocardial infarction, non-fatal stroke or death from cardiovascular causes.
The study found no statistical difference in the primary outcome however there was a lower risk of stroke (Hazard ratio 0.59, 95% CI 0.39 – 0.89, p=0.01). It was also noted that there was a higher risk of adverse events (3.3% of participants in the intensive arm versus 1.3% in the standard arm).
The authors conclude that, “a systolic blood pressure of less than 120 mm Hg, as compared with less than 140 mm Hg, did not reduce the rate of a composite outcome of fatal and nonfatal major cardiovascular events”.
The current NICE guideline recommends that blood pressure is treated to below 140/80mmHg (or 130/80mmHg in the presence of kidney, eye or cerebrovascular damage) and that fibrates are used in addition to statins to treat hypertriglyceridaemia (2.3 to 4.5 mmol/L) in individuals with high cardiovascular risk.
Action: Clinicians should be aware of these analyses. The results indicate that aggressive treatment to reach targets below those recommended by NICE results in no or limited benefit while increasing the risk of side effects.
The British Medical Journal has published a ‘Change Page‘ that reviews the current evidence for aspirin in the prevention of primary cardiovascular events. Change Page articles highlight areas of practice where there is an immediate need for a change in practice to make it consistent with current evidence.
This article notes that recent systematic reviews and meta-analyses have identified that the benefit of using aspirin for primary prevention is much lower than previously assumed and does not appear to outweigh the harms associated with the treatment.
This article also draws attention to the disparate recommendations in current guidelines. For example, a recent update to the Scottish Intercollegiate Guidelines Network (SIGN) Diabetes guideline has stated that “low-dose aspirin is not recommended for the primary prevention of vascular disease in patient with diabetes” while the British Hypertension Society (BHS) has reaffirmed it’s recommendation for “low dose aspirin for primary prevention of cardiovascular disease in those for whom the balance of benefit outweighs the risk of harm“.
This article urges a review of therapy for all patients taking aspirin for primary prevention and recommends that “the decision to stop or continue treatment should be made with these patients after fully informing them of the available evidence“.
Action: Clinicians should not routinely start aspirin for the primary prevention of cardiovascular disease. Patients on current treatment should be reviewed to assess whether continued therapy is justified.
The Midlands Therapeutic Review and Advisory Committee has published an updated review of sitagliptin (Januvia®).
This review still places sitagliptin as having a lower place in therapy but supported by stronger evidence. It was previously known that in combination with other hypoglycaemic drugs it has been shown to lower HbA1c to a greater extent than placebo. Additional research since the last review in 2008 has demonstrated that monotherapy also reduced HbA1c to a greater extent than placebo. However, there are still no long term data for sitagliptin on mortality or cardiovascular outcomes.
MTRAC recommends that, “sitagliptin is suitable for prescribing in primary care within its licensed indications and according to National Institute for Health and Clinical Excellence (NICE) guidance“.
Action: Clinicians should be aware of this review. It is a useful summary of the current evidence and makes sound recommendations for the use of sitagliptin.
Clinical Knowledge Summaries (CKS) has been updated in April 2010 for the following clinical areas:
Action: Clinicians who see patients with any of these conditions may find the new and updated information useful when reviewing current clinical practice.
The British Medical Journal has published the results of a prospective cohort study that aimed to derive age and sex related ambulatory blood pressure equivalents to clinic blood pressure thresholds for diagnosis and treatment of hypertension.
The study was conducted in 11 centres in Australia and involved 8,529 participants. Ambulatory results were compared to those taken by trained staff and also doctors.
The mean blood pressure measured by trained staff while the patient was seated as 142/82mmHg compared to 150/89mmHg when measured by a doctor. The measurements taken by trained staff were 6/3mmHg higher than daytime ambulatory blood pressure and 10/5mmHg higher than 24 hour blood pressure. The authors also note that the closer the patient’s blood pressure is to normal levels, the closer is the agreement between daytime ambulatory and clinic blood pressure.
This study adds weight the information contained in the NICE guideline for Hypertension which indicates that ambulatory readings are commonly lower than clinic readings by between 10/5mmHg and 20/10mmHg.
The authors conclude that, “these results provide a framework for the diagnosis and management of hypertension using ambulatory blood pressure values“.
Action: Clinicians who use and interpret ambulatory blood pressure measurements may find the figures reported in this study useful for identifying thresholds for initiation or changes to treatment.