The New England Journal of Medicine has published the results of a study that aimed to assess whether exemestane (Aromasin®) is an effective treatment for the prevention of breast cancer in postmenopausal women.
Tamoxifen and raloxifene have limited acceptance in preventing breast cancer in high risk individuals (although this is not a licensed indication for either drug in the UK) but use in this way is very limited. This trial aimed to assess whether an aromatase inhibitor might be as effective but with fewer side effects.
This study recruited 4,560 women aged 35 years an older with at least on of the following risk factors:
- 60 years of age or older
- 5-year cancer risk score greater than 1.66% (using the Breast Cancer Risk Assessment Tool)
- prior atypical ductal or lobular hyperplasia or lobular carcinoma in situ
- ductal carcinoma in situ with mastectomy
The study had a median follow up period of 35 months. During that time there was a 65% relative risk reduction in the annual incidence of invasive breast cancer (0.19% versus 0.55%, hazard ratio 0.35, 95% CI 0.18-0.70, P=0.002) and a 53% relative risk reduction in the annual incidence of invasive plus non-invasive breast cancers (0.35% versus 0.77%, hazard ratio 0.47, 95% CI 0.27-0.79, P=0.004). Adverse events occurred in a high proportion of both arms of the study (88% of the exemestane group and 85% of the placebo group) and were not significantly different.
The authors conclude that, "exemestane significantly reduced invasive breast cancers in postmenopausal women who were at moderately increased risk for breast cancer".
The study does have some limitations. Patients in the study were not exclusively individuals who had never had cancer so the population cohort is a mixture of primary and secondary prevention. The study also compared treatment to placebo rather than an active comparator.
This study reports some impressive relative risk reductions but the actual risk reductions are less impressive. The 65% decrease in annual incidence of invasive breast cancer is an actual risk reduction of 0.35% (0.55% - 0.19% = 0.35%). This means 278 postmenopausal women like those recruited to this study would need to be treated with exemestane for a year instead of placebo to prevent one case of invasive breast cancer. 30 days supply of exemestane currently costs £88.80, so preventing this one case would require an investment of almost £300,000. This does not appear to be a cost effective use of NHS resources.
Action: The emotive nature of cancer and the impressive relative risk reductions quoted may generate patient queries. Clinicians should be aware of the actual risk reductions. Patients should be encouraged to participate in screening to aid early diagnosis.
The European Medicines Agency (EMA) has announced (PDF) that it is conducting a safety review of pioglitazone containing medicines. The Food and Drugs Administration (FDA) is conducting a similar review.
This review is being conducted as a result of a recently completed French study which found an increased risk of bladder cancer. The French authorities have suspended the product license as a result of this finding pending a full review.
The results of the review are expected to be available in July. The EMA also state that the association between bladder cancer and pioglitazone use has been under continuous review since the product license was granted in 2000. Three previous reviews have failed to confirm a clear association but have indicated a potential increased risk in those with longest exposure and highest cumulative dose.
Action: Clinicians should be aware of this review. It would be prudent to avoid initiating new treatment with pioglitazone until the review is completed. Patients currently taking pioglitazone who are concerned about the potential increase in risk could be reviewed and have their treatment changed if this will maintain patient-clinician trust.
The Journal of the American Geriatrics Society has published the results of a study that aimed to assess whether the use of medications with possible and definite anticholinergic activity increases the risk of cognitive impairment and mortality in older people and whether risk is cumulative. The results have been reported in the general media (BBC).
The study was a 2 year long study involving 13,004 participants aged 65 years and older. Baseline assessment of Mini-Mental State Examination (MMSE) were taken and reviewed over 2 years for decline. At baseline 47% of participants were prescribed a medication with possible anticholinergic properties and 4% were prescribed a medication with definite anticholinergic properties. The data were corrected for several variables including age, sex, educational level, social class, number of non-anticholinergic medications, number of co-morbid health conditions and cognitive performance at baseline.
It was found that use of medicines with definite anticholinergic properties was associated with a 0.33-point greater decline in MMSE score than not taking anticholinergic drugs (95% CI 0.03-0.64, p=0.03). The use of medicines with possible anticholinergic properties was not associated with a decline in MMSE (0.02, 95% CI 0.14-0.11, P=0.79).
Both types of anticholinergic drugs were associated with increased two-year mortality. (Definite anticholinergic drugs: Odds Ratio 1.68; 95% CI 1.30-2.16; P=0.001, Possible anticholinergic drugs: Odds Ratio 1.56; 95% CI 1.36-1.79; P=0.001).
The authors conclude that, "the use of medications with anticholinergic activity increases the cumulative risk of cognitive impairment and mortality".
The study does have some limitations. This is observational data and cannot prove cause and effect. Additionally, issues of compliance, duration, interrupted use, and the effect of different doses also require consideration. The paper also categorised the drugs according to the Anticholinergic Cognitive Burden Scale (ACB) but this scale may not reflect the potency of anticholinergic activity of the drug in the body. Finally, although the study corrected for many health-related factors there still remains the possibility that there is residual confounding between health status and cognitive function.
Action: Clinicians should be aware of this study and the wide media reporting. Further research is needed to confirm and extend our understanding. It may be prudent to review patients who are using anticholinergic medication and consider discontinuing use where clinically appropriate.
The National Prescribing Centre has published a MeReC Bulletin (PDF) that focuses on how to best manage blood glucose in the overall context of preventing both macrovascular and microvascular diabetic complications.
This bulletin uses a case study approach to discuss treatment priorities, optimal blood glucose control and hypoglycaemic drug therapy.
In particular this review discusses the relative advantages and disadvantages of newer hypoglycaemic agents including long-acting insulin analogues, the place for triple therapy and the optimal blood glucose.
Action: Clinicians who treat patients with type 2 diabetes will find this bulletin is a useful review of the management of blood glucose.
The Dementia Action Alliance (DAA) has issued a call to action to gain support from patients, carers and clinicians to ensure that all people with dementia who are receiving antipsychotic drugs should receive a clinical review from their doctor to ensure that their care is compliant with current best practice and guidelines and that alternatives to medication have been considered by 31 March 2012.
The DAA represents over 40 organisations who are committed to transforming the quality of life of people living with dementia in the UK including the Alzheimer's Society, the NHS Institute for Innovation and Improvement and the National Institute for Health and Clinical Excellence.
Action: Clinicians should be aware of this campaign. Media coverage may generate queries from patients and carers which will present an opportunity to offer a clinical review.
