Issue
50
RCTs vs Clinical Practice
A recent Bandolier faced the important question
of whether the results of clinical trials are applicable to clinical
practice. One of those simple questions for which simple answers are
infrequently available from actual evidence. Because clinical trials
often test a single technology and have defined inclusion and
exclusion criteria, it can seem as if they could never apply to a
clinic of octogenarians all with several other diseases.
It is unusual to have results from a
meta-analysis of randomised trials compared with results of clinical
practice, but for anticoagulation a group from London have turned up
trumps and another from Glasgow provides useful information about
anticoagulation in the elderly
The main study used a prospective cohort or
retrospective case note reviews of anticoagulation for atrial
fibrillation in clinical practice. Patients had to be in ordinary
clinical practice settings unrestricted by age or other
considerations. Anticoagulation had to be conducted in routine, not
research, settings, and there had to be longitudinal data on stroke
rates and haemorrhagic complications.
Data from such studies was compared with a
meta-analysis of randomised controlled trials. There were three
eligible clinical practice studies performed in the USA, Canada, and
England. They all had similar definitions for atrial fibrillation,
risk, criteria for anticoagulation and for outcomes. In all there
were 410 patients with 842 years of follow up, compared with 1225
patients and 1889 patient years in randomised trials.
Compared with randomised trials, patients in
clinical practice were older, were more likely to be women, and have
diabetes, previous stroke or heart failure, but less likely to have
ischaemic heart disease.
Rates of ischaemic stroke, intracranial
haemorrhage and major bleeding were similar for clinical practice
and clinical trials. Minor bleeding occurred more frequently in
clinical practice, though individual study rates varied markedly.
Confidence that clinical trial results translate
to clinical practice is important in implementing therapy, and
fulfilling guidelines and service frameworks. People want to know
that what they are doing for their patients will benefit them. Here
we have evidence that a wet Thursday in Grimsby is much the same as
anywhere else when it comes to using anticoagulation for atrial
fibrillation. Older patients did as well as younger ones.
Ref to
Bandolier search page - such good reading!
Back
to top
Evidence for lifestyle changes
improving health
Christmas seems like a good time for Bandolier’s
ten lifestyle tips to help avoid seeing
a doctor about heart disease or cancer, based on good quality
information.
Eat whole grain foods (bread, or rice, or pasta)
on four occasions a week. This will reduce the chance of having
almost any cancer by 40%.
Don't smoke. If you do smoke, stop. Nicotine patches, gum or
inhaler won't help much, and acupuncture won't help at all. Try to
reduce your smoking, as there is a profound dose-response (the more
you smoke, the
respiratory disease). So cut down to below five
cigarettes a day and leave long portions of the day without a
cigarette.
Eat at least five portions of vegetables and
fruit a day, and especially tomatoes (including ketchup), red grapes
and the like, as well as salad all year. This
reduces the risk of stroke dramatically
reduces the risk of diabetes considerably
will reduce the risk of heart disease and
cancer.
Use Benecol instead of butter or margarine. It
really does reduce cholesterol, and reducing cholesterol will reduce
the risk of heart attack and stroke even in those whose cholesterol
is not particularly high.
Drink alcohol regularly. The equivalent of a
couple of glasses of wine a day or a couple of beers is a good
thing. A day without alcohol won't hurt. Think of it as medicine.
Eat fish. Eating fish once a week won't stop you
having a heart attack, but it reduces the likelihood of you dying
from it by half.
Take a multivitamin tablet every day, but be sure
that it is one with at least 200 micrograms of folate. The evidence
is that this can substantially reduce chances of heart disease in
some individuals, and it has been shown to reduce colon cancer by
over 85%. It may also reduce the likelihood of developing dementia.
Folate is essential in any woman contemplating pregnancy because it
will reduce the chance of some birth defects.
If you are pregnant or have high blood pressure,
coffee is best minimised. For the rest of us drinking four cups of
coffee a day is likely to reduce our chances of getting colon cancer
and Parkinson's disease.
Get breathless more often. You don't have to go
to a gym or be an Olympic marathon runner. Simply walking a mile a
day, or taking reasonable exercise three times a week (enough to
make you sweat or, for ladies, glow) will substantially reduce the
risk of heart disease. If you walk, don't dawdle. Make it a brisk
pace. One of the benefits of regular exercise is that it strengthens
bones and keeps them strong. Breaking a hip when elderly is a very
serious thing.
Check your height and weight on a chart to see if
you are overweight for your height. Your body mass index is the
weight in kilograms divided by the height in metres squared: for
preference it should be below 25. If you are overweight, lose it.
This has many benefits.
There is no good evidence on simple ways to lose
weight that work. Crash diets don't work. Take it one step at a
time, do the things that are possible now, and combine some calorie
limitation with increased exercise. The good news is that in a few
years time we may have some appetite suppressants to make it easier
but, as gluteus(?) maximus might have said, ‘not yet’. (For the
older readers this is a Kinematographic reference)
See reference to last
piece
Back
to top
Cranberry Juice for Urinary Tract
Infection
Christmas also seems a good time to mention a
recent well-conducted RCT involving 150 elderly women and published
in JAMA showing that cranberry juice is effective in reducing rates
the effect of cranberry juice was more pronounced in converting
urine samples out of a state of bacteria with pyuria as compared
with preventing the conversion of non-infected urine samples to
infection.
This does not imply that a regimen of cranberry
juice should displace antibiotics as the therapy of choice when
treatment is needed, but it could be a useful adjunct to treatment
in high risk groups.
It is certain, though, that drinking cranberry
juice does no harm. Addition of cranberry juice to dietary regimens
in circumstances where urinary tract infections have a high
incidence would be sensible, and would probably reduce both the
incidence of infection and the need for antibiotic treatments
Problem with this trial was that it seemed to
come from some farm growing cranberries! See the reference.
Ref (Web)
Back
to top
|
