This week in the BMJ
Volume 329, Number 7456, Issue of 3 Jul 2004Adverse drug reactions cause too many hospital admissions
Adverse drug reactions cause too many hospital admissions
One in 16 admissions to hospital is due to adverse drug reactions. Analysing 18 820 admissions to hospital in Merseyside, Pirmohamed and colleagues (p 15) found that 1225 admissions (6.5%) were related to adverse drug reactions. Patients were in hospital for eight days on average, accounting for 4% of bed capacity, and 28 (0.15%) died. Most reactions were due to aspirin, diuretics, warfarin, and non-steroidal anti-inflammatory drugs; the most common reaction was gastrointestinal bleeding. Adverse drug reactions are likely to cost the NHS £466m every year, say the authors, and most are avoidable.
|
![[To top]](/icons/back.gif){kind=icon}
Uterine rupture is more likely, but not common, after previous caesarean section
The risk of uterine rupture during labour in women who have had a previous caesarean section is small. Reviewing 568 articles published since 1980, Guise and colleagues (p 19) found that, in women delivering vaginally after a previous surgical delivery, the risk of uterine rupture during labour was increased by 2.7 per 1000 cases, the additional risk of perinatal death was 1.4 per 10 000, and the additional risk of hysterectomy was 3.4 per 10 000. It would require 370 elective caesarean sections to avoid one symptomatic uterine rupture in women who had a previous caesarean section.
Forceps and vacuum delivery pose the same mortality risk for babies
Neonatal mortality is similar after vacuum delivery and forceps delivery. Demissie and colleagues (p 24) analysed more than 12 million deliveries in US and New Jersey birth cohort files and found that, compared with babies delivered with forceps, those who had vacuum deliveries had a lower risk of birth injuries, neonatal seizures, and assisted ventilation but a higher risk of post-partum haemorrhage and shoulder dystocia. Fetal distress was more common with instrumental delivery, and nulliparous women were more likely than parous women to have instrumental deliveries. Vacuum extraction does have risks, but it remains a safe alternative to forceps delivery, conclude the authors.
|
Does St John's wort interact with conventional drugs?
The effect of St John's wort (Hypericum perforatum) on the bioavailability of conventional drugs remains unclear. Reviewing 22 trials, Mills and colleagues (p 27) found that St John's wort either had no effect or decreased the availability of conventional drugs when used together. Most studies used a "before and after" design, and the overall quality of the trials was limited in scope and methodological quality.
|
Results of clinical trials are not generalisable
The selection process for participation in clinical trials means that participants may not represent average patients, and that extrapolating data can be misleading. Dieppe and colleagues (p 31) reviewed trials on non-steroidal anti-inflammatory drugs in osteoarthritis and compared the participant profile to information from the medicine monitoring database on 131 410 patients taking the drugs in Scotland. People at risk of adverse effects, minority groups, and older people were often excluded from trials. Drugs tend to be used for a wider range of indications than those for which they are trialed, and the harms observed in practice are different from those reported in trials. Databases that link prescribing to hospital data and other health records are needed to assess the relative benefits and harms of drugs, say the authors.
Do antidepressants reduce suicide?
The balance between risks and benefits of antidepressants is not clear. Reviewing available data on these drugs, Gunnel and Ashby (p 34) found it hard to find direct evidence that antidepressants prevent suicide. Most trials are underpowered to detect a difference in the risk of suicide, and time trends analysis of suicide rates at population level are used as a surrogate measure. Suicides rates have fallen in recent years, but this may not be due to use of antidepressants, say the authors; future trials should be sufficiently long to detect longer term benefits and harms, and should systematically collect data on suicidal thoughts and behaviour.
|
What's new
Keep updated
Services
Tools
Online poll
Resources
Print issues
