Gastroenterology has published the results of a hospital-based case-control study that aimed to investigate the effect of antidiabetic therapies on the risk of pancreatic cancer.
The study was conducted as a cancer centre in America between 2004 and 2008. The study included 973 patients with pancreatic adenocarcinoma and 863 controls. Medical histories were collected by personal interview and frequency of use of antidiabetic therapies was compared between cases and controls.
In patients with diabetes, metformin was found to significantly reduce the risk of pancreatic cancer. Insulin and insulin secretagogues (sulphonylureas and metaglinides) significantly increased the risk while glitazones increased the risk but not significantly.
- Metformin - Odds ratio (OR) 0.38 [95% confidence interval (CI) 0.22 - 0.69, p=0.001]
- Insulin - OR 4.99 [95% CI 2.59 - 9.61, p<0.001]
- Insulin secretagogues - OR 2.52 [95% CI 1.32 - 4.84, p=0.005]
- Glitazones - OR 1.55 [95% CI 0.78 - 3.07, p=0.213]
These differences remained in never-users of insulin but the risk associated with insulin secretagogues became non-significant in patients who had diabetes for longer than 2 years.
The authors of this study highlight several potential limitations including the design of the study being open to reporting bias, the study having been conducted in one location which may mean the results are not representative of a wider population and the sub group analyses only used small numbers of patients. They recommend that these observations should be confirmed in larger studies.
Action: Metformin is already recommended as first line treatment in type 2 diabetes. An accompanying editorial notes that these findings may "provide an additional incentive for patients and physicians to follow this recommendation".
The Department of Health has announced the priority groups for vaccination against swine 'flu.
The Joint Committee on Vaccination and Immunisation (JCVI) produced the initial recommendations which were reviewed and endorsed by the Scientific Advisory Group for Emergencies (SAGE).
The following groups will be offered vaccination and are listed in priority order:
- People aged over six months and under 65 years in current seasonal flu vaccine clinical at-risk groups
- All pregnant women, subject to licensing conditions on trimesters
- Household contacts of people with compromised immune systems e.g. people in regular close contact with patients on treatment for cancer
- People aged 65 and over in the current seasonal flu vaccine clinical at-risk groups. This does not include otherwise healthy over 65s, since they appear to have some natural immunity to the virus
Vaccination of front-line health and social care workers will start at the same time as the first priority group. The vaccination programme will only commence after a vaccine has been licensed by the European Medicines Agency.
Action: Clinicians should be aware of the groups who will be offered vaccination and how they are being prioritised.
The National Prescribing Centre has published an article that provides some clarification of the situation that has arisen following the introduction of generic clopidogrel.
The manufacturer of the branded product (Plavix®) has written to healthcare professionals to highlight the different salt formulations being used in the generic products and the differences in the approved product licence. The generic products are licensed for use in the prevention of atherothrombotic events (myocardial infarction, stroke or peripheral vascular disease) but are currently unlicensed in acute coronary syndrome (ACS). It remains unclear if this difference exists for clinical, product patent or economic reasons.
The differences still place clinicians and dispensers in a situation where prescribing may result in use of a product outside of the licensed indication. The decision to intentionally prescribe generic clopidogrel outside of the current licensed indication will require consideration of the additional clinical responsibility involved and the likely cost benefits.
Updates to clinical systems will also be required to allow for generic prescribing of the particular salt preparations that are available.
Action: Clinicians need to consider whether they believe that use of generic clopidogrel for ACS is clinically reasonable and implement appropriate procedures at local level.
The Medicines and Healthcare products Regulatory Agency (MHRA) has published Drug Safety Update for August 2009 (PDF).
This issue contains Hot Topics on the safety of oseltamivir (Tamiflu®) and zanamivir (Relenza®) during the swine 'flu outbreak and an update on the safety of herbal products.
The Stop Press section advises that prescribing restrictions for rotigotine patches (Neupro®) have now been lifted. The restrictions were put in place in July 2008 when crystals were found to develop in the patches under certain conditions. An improved method of distribution, including refrigeration, appears to have resolved these issues.
Action: Clinicians will find this publication to be a useful review of current issues in drug safety.
The Scottish Medicines Consortium (SMC) has issued its monthly advice on new medicines.
Rotigotine (Neupro®) has been accepted for the symptomatic treatment of moderate to severe idiopathic restless legs syndrome in adults. Treatment should only be used in patients who score 15 points or more on the International Restless Legs Scale (IRLS).
Calcipotriol and betamethasone gel (Xamiol®) has been accepted for the topical treatment of scalp psoriasis. The combination product has been shown to be more effective than monotherapy in short-term studies.
Action: Clinicians should be aware of the recommendations of the SMC. Routine use of rejected and restricted medicines should be avoided.