Prescribing Advice for GPs

Antihypertensives and new onset diabetes

September 7, 2006 on 11:23 am | In Prescribing Extra - Other |  Print | No Comments

PharmaTimes has reported [Registration required] "amlodipine cuts new diabetes risk by 34%". The headline is derived from a clinical trial update that examined new onset diabetes in the ASCOT-BPLA trial. The update was presented at the 2006 World Congress of Cardiology.

The Blood Pressure Lowering Arm of the ASCOT Study was main reason for the review of the NICE Hypertension Guidelines. However, focussing solely upon one aspect of the trial results is inappropriate and could prove dangerous.

At the same event, it was reported that patients with acute coronary syndrome have a much lower mortality and morbidity if they continue to take beta-blockers. After just 6 months mortality rates increase from 0.4% in those taking beta-blockers to 20.2% in those who were not taking beta-blockers. Clearly, beta-blockers still have a useful place in some patients.

Action: This update provides a useful reminder that clinicians should be following the NICE Hypertension Guideline for patients with uncomplicated hypertension. Patients with diabetes or acute coronary syndrome should be treated after due consideration of their other morbidities.

Post hoc analysis of TNT

September 6, 2006 on 1:06 pm | In Prescribing Extra - Drugs |  Print | No Comments

The Lancet has made a post hoc analysis of the Treating to New Targets (TNT) study available as an early online publication.

This analysis examines the effects that aggressive lipid lowering therapy with atorvastatin 80mg compared to regular lipid lowering with atorvastatin 10mg had in patients with metabolic syndrome. Metabolic syndrome was defined by the NCEP ATP III criteria. The analysis included 5,584 of the original 10,001 patients recruited to the TNT study.

Efficacy assessment was still based upon the primary outcome measure of a major cardiovascular event, defined as death from CHD, non-fatal MI, resuscitated cardiac arrest and fatal or non-fatal stroke.

Over the average follow up of 4.9 years 367 events occurred in the 2,820 patients assigned to the atorvastatin 10mg arm and 262 events occurred in the 2,764 patients assigned to the atorvastatin 80mg arm. This equates to an absolute risk reduction of 3.5% and a Number Needed to Treat (NNT) of 28 over 4.9 years.

Throughout this analysis no mention is made of adverse events. In the original study, patients in the 80mg arm were more statistically likely to experience a treatment-related adverse event (8.1% vs. 5.8%). Persistent liver enzyme elevation (1.2% vs. 0.2%) and treatment discontinuation (7.2% vs. 5.3%) were also more likely.

The original study reported an NNT of 45 to prevent one event over 4.9 years but against this there is a Number Needed to Harm (NNH) of 43 for an adverse event and NNH of 53 for a discontinuation. Aggressive treatment will only work if it can be tolerated and therefore taken by patients.

Action: Considering the limitations of post hoc analyses and the additional adverse events experienced by patients in the aggressive arm of the study it is inappropriate to change practice based on these findings. The study may formulate a hypothesis about targeting aggressive treatment to those at highest risk that should be tested under controlled trial conditions.

Childhood Vaccinations changes implemented

September 4, 2006 on 10:08 am | In Prescribing Extra - Other |  Print | No Comments

Changes to the Childhood Vaccination Programme announced earlier this year came into force today.

The changes introduce a pneumococcal conjugate vaccine (Prevenar^®) into the schedule which will protect against pneumonia, septicaemia and meningitis caused by Streptococcus pneumoniae. The introduction of this vaccine has some additional effects changing the dosing schedule for some of the other vaccinations.

More information on the current programme is available on the NHS Immunisation website. More information about the pneumococcal vaccination is available in the Summary of Product Characteristics.

Action: Clinicians should already be aware of the changes but may appreciate a reminder about the implementation date.

Learning via blogs

September 1, 2006 on 4:13 pm | In Admin Information |  Print | No Comments

E-Health Insider reports on the publication of a paper at BioMed Central that concludes blogs (websites like this one) can be used to enhance learning experiences for clinicians.

The paper cites the main advantages of blogs are the ease of use and availability. This would include anywhere web-access, search facility, RSS and email subscriptions.

The main disadvantage is information quality because of the collaborative authoring of some blogs. This site operates in a “closed environment” meaning one person operates the whole site writing all the articles and moderating any comments.

Action: This site had 14,000 visitors in August; surely you all know this already!