Clinical Guidelines for Acute Stroke Management - Living on the EDge

7 SECONDARY PREVENTION
7.1 Behaviour change to prevent another stroke has been given a Consumer Rating of 9.7/10.
7.2 -7.8 Medical or surgical treatments to prevent another stroke has been given a Consumer
Rating of 9.6/10.
7.3 Concordance with medication to prevent another stroke has been given a Consumer
Rating of 9.6/10.
A person with stroke has an accumulated risk of
subsequent stroke of 43% over 10 years with an
annual rate of approximately 4%. 351 The rate of strokes
after TIA is significantly higher (up to 20% after
3 months) suggesting greater opportunities to prevent
stroke after TIA. 35 Secondary prevention there<strong>for</strong>e
relates to both stroke and TIA. Data from overseas
highlight the current underutilisation of secondary
prevention strategies <strong>for</strong> people with stroke and TIA. 35,
352, 353
Long term management of risk factors is the
primary role of GPs and good communication
between secondary and primary care is important
(see section 1.10 Shared care).
7.1 Behaviour change
Evidence on behaviour change strategies targeting
lifestyle factors to prevent recurrence of stroke is
limited and often derived from cohort studies of
primary prevention.
> Smoking increases the risk of both ischaemic and
haemorrhagic stroke due to vascular narrowing and
changes in blood dynamics. 354-356 While no RCTs
have been conducted, observational studies have
found the risk from smoking decreases after
quitting with the risk disappearing altogether after
5 years. 357, 358 Several Cochrane systematic reviews
have been undertaken related to different therapies
<strong>for</strong> smoking cessation. Nicotine replacement
therapy is beneficial and doubles the chances of
smoking cessation. 359 Some antidepressants (i.e.
bupropion and nortriptyline but not selective
serotonin reuptake inhibitors) aid long-term smoking
cessation. 360 Varenicline (a nicotine receptor partial
agonist) has recently been developed <strong>for</strong> long-term
smoking cessation with a threefold success rate
compared with non drug quit attempts. 361
Varenicline has also been found to be more
beneficial than the antidepressant bupropion. 361
A number of behavioural therapies delivered by
different health professionals in different settings
have demonstrated modest effects <strong>for</strong> smoking
cessation in general populations and should be
provided via an individualised approach either in a
group or on a one-to-one basis. 362-365 One good
example of such behavioural therapies involves
telephone counselling, which improved smoking
cessation rates particularly when three or more call
backs are made. 366
> Diet has an impact on a number of risk factors and
can provide additional benefits to pharmacological
interventions in people with vascular disease.
Reducing dietary salt in people with cardiovascular
disease (especially in those with high blood
pressure) modestly reduces blood pressure and
may there<strong>for</strong>e be beneficial to prevent stroke. 367-371
A meta-analysis of cohort studies found a diet high
in fruit and vegetables (>5 servings per day)
reduced the risk of stroke. 372 Similarly, a diet that is
low in fat but high in fruit and vegetables has been
shown to be effective in risk reduction <strong>for</strong> those with
cardiovascular disease. 370, 373-375 Similar dietary
modification has also been shown to be beneficial
<strong>for</strong> those with dyslipidemia 376-378 and obesity (to
assist in controlling hypertension). 379 Supplementary
antioxidants and vitamins, however, have not been
found to reduce stroke. 380-382 One recent large
RCT of a general dietary intervention (intended to
be low in fat and high in vegetables, fruits and
grains) in women 50-79 years old noted a
significant reduction in diastolic blood pressure and
low-density lipoprotein cholesterol. 383 However, no
difference in stroke incidence or coronary heart
disease was found. The authors suggested a more
individual, targeted approach may be needed. 383
Recommendations <strong>for</strong> dietary intake are available
from other guidelines and provide useful in<strong>for</strong>mation
based on cardiovascular disease and general
populations.
384, 385
> There is strong evidence from meta-analysis of
cohort studies that exercise has a protective effect
on stroke. 386-388 However, <strong>for</strong> secondary stroke
prevention, there is currently a lack of direct
Section 7 Secondary Prevention
43