Research of the week
Postmenopausal HRT and cardiovascular risk
JAMA 2007; 297: 1,465–77
While anecdotal reports have shown a reduction in cardiovascular events in post-menopausal women taking HRT, recent trials such as the WHI provided evidence to the contrary. Researchers have since suggested errors in methodology may not be the only factor at work here. It is hypothesised that early treatment is beneficial, whereas late use of HRT may be a risk factor for coronary artery disease.
This study analysed WHI data and concluded that women who commenced HRT within 10 years of the menopause had a reduced risk (0.76 hazard ratio) of developing CHD whereas in those who experienced the menopause more than 20 years before starting HRT, the hazard ratio for CHD was 1.28.
More robust data are required before definitive clinical guidelines are developed.
PSA doubling time and prostate cancer risk
Mayo Clin Proc 2007; 82: 422–7
This study was based on patients who had undergone retropubic prostatectomy for prostate cancer. The aim was to risk-stratify recurrence based on PSA doubling time (PSA-DT).
Patients who had a PSA >0.4ng/ml (27 per cent of all patients surgically treated for prostatic adenocarcinoma) were followed up for nearly 10 years in this American study.
Of the cohort, 30 per cent had a PSA-DT of less than one year, 34 per cent between one and 9.9 years and 36 per cent had a PSA-DT of more than 10 years.
Those with a long doubling time had a reduced risk of local recurrence, systemic progression and death (hazard ratio 0.09, 0.05 and 0.15, respectively) compared with those with a short PSA-DT.
Serological testing for coeliac disease
BMJ 2007; 334; 729 doi:10.1136/bmj.39133.668681.BE
Data have suggested that coeliac disease is underdiagnosed and might affect up to 1 per cent of the UK population. Those with atypical presentations often have delayed diagnosis.
While serology using tissue transglutaminase (TGG) and endomysial IgA yield >95 per cent negative predictive value, the gold standard remains endoscopy and duodenal biopsy. Endoscopy is an invasive test, with inherent costs and risks.
In this retrospective study the authors developed a diagnostic algorithm based on a cohort of coeliac patients, proven on biopsy.
These criteria were then applied and tested on a second cohort. The algorithm, based on symptoms and serology, was found to have 100 per cent sensitivity and 100 per cent negative predictive value.
Interestingly, some patients were found to have a negative biopsy despite having high-risk symptoms and having antibodies (60.8 per cent positive predictive).
Sumatriptan-naproxen for acute treatment of migraine
JAMA 2007; 297: 1,443–54
Migraine remains difficult to manage and significantly affects quality of life. This blinded study evaluated naproxen (500mg), sumatriptan (85mg), naproxen/sumatriptan combined pill and placebo in the management of migraine in nearly 3,000 patients.
Combination therapy showed a statistically significant improvement in headache and photophobia (but not nausea) both at two hours and during the interval 2–24 hours post-treatment, compared with placebo and monotherapies.
Some 57–65 per cent of patients were pain-free at two hours with sumatripatan-naproxen compared with around 28 per cent with placebo. Given that combination therapy is almost twice as effective as monotherapies, sumatriptan and NSAIDs together might significantly improve patients’ symptoms.
How effective are rapid-access chest pain clinics?
Heart 2007; 93: 458–63
CHD remains the number one cause of death in the UK. Angina is not always easy to diagnose and rapid-access chest pain clinics provide a cost-effective method to diagnose CHD, or do they? Only around 70 per cent of patients with angina will have a positive exercise tolerance test. This UK-based study looked at how effective these clinics were by comparing coronary event rates in patients diagnosed with angina to those diagnosed with non-cardiac chest pain.
Nearly 9,000 patients were followed over three years in this prospective study. Angina patients had a 16.52 per cent cumulative risk of an acute coronary event compared with 2.73 per cent in non-angina patients. Those who suffered a cardiac event but who were deemed not to have CHD (32.4 per cent), were more likely to be south Asian, younger, have atypical chest pain with a normal resting ECG.
Dr Thakkar is a GP in Wooburn, Buckinghamshire, and a member of our team who regularly review the journals