CASE REPORT

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RECURRENT STROKE: WHAT HAVE WE LEARNT?

Table 1. Laboratory results

Investigation	Results
Fasting glucose	6.6 mmol/L
Triglyceride	0.8 mmol/L
Total cholesterol	3.5  mmol/L
HDL- cholesterol	1.28 mmol/L
LDL-cholesterol	1.86 mmol/L
HbA1c	5.6%
Urea	6.2 mmol/L
Creatinine	87 mmol/L
Liver function test	Normal
Chest x-ray	Normal
ECG	Normal
Urinalysis	Protein negative

Progress
Subsequently BS suffered two further episodes of stroke within three months. He didn’t make a full recovery and had a neurological sequel. His motor power at the left shoulder joint was 3/5, at elbow and wrist joint was 0/5. In the lower limb, his power was 4/5 at the hip, knee and ankle. He was able to perform activities of daily living and his urination and bowel were normal. However, he was depressed and had poor sleep at night with decreased appetite. He was referred to occupational therapist for assessment of activity of daily living (ADL) and for extensive physiotherapy. He was started on tab citalopram 20 mg nocte, a selective serotonin reuptake inhibitors for depression and was referred to a social worker for financial problems. After a few months, review showed that his depressive symptoms were better but the neurological signs persisted.

DISCUSSION

Stroke continues to be an important health issue, and it remains a leading cause of death and disability. Approximately 85% of strokes are ischaemic in nature and the rest is attributable to haemorrhagic causes such as subarachnoid or intracerebral haemorrhage.¹

Why this patient has recurrent episodes of stroke?

In this patient, it is unclear why he had so many episode of recurrent stroke even though he non-smoking, didn’t have atrial fibrillation, and his diabetes and dyslipidemia were under control. His BP was higher than the target of 130/80 mmHg (for diabetic with hypertension). His blood pressure was unknown in the past years when was under the care of GP. In the earlier years of his stroke, his compliance to medication could be an issue as had defaulted follow up and treatment until later years. Therefore his blood pressure treatment might not be optimised. Furthermore the delay in initiation of aspirin, hypertensive, diabetic and lipid therapy after the first TIA could have contributed to his

recurrent stroke. Another factor for his recurrent stroke despite taking antiplatelet could be attributed to intracranial carotid artery stenosis; this may need other modes of treatment such as carotid endarterectomy.

Can this patient’s recurrent stroke be prevented?
There are few strategies for primary and secondary prevention of stroke.

1. Strategies for primary prevention of stroke
In primary prevention, control of risk factors such as lifestyle modifications (weight loss, alcohol restriction, regular aerobic physical activity, and smoking cessation), measures to control blood pressure, cholesterol levels, diabetes mellitus and atrial fibrillation are important.² In this patient his first cardiovascular event of TIA occurred possibly due to undiagnosed hypertension and dyslipidemia. Therefore early screening and lifestyle modifications play an important role in primary prevention of stroke.

2. Strategies for secondary prevention of stroke
Stroke is a heterogeneous disorder in which multiple disorders can lead to occlusion or rupture of blood vessels supplying the brain.4 Modification of stroke risk factors is the principal therapeutic approach. Numerous RCTs have demonstrated that lowering blood pressure in patients with hypertension prevents both haemorrhagic and ischemic strokes. Indeed, systolic BP is a stronger risk factor for stroke than diastolic BP. Regardless of selected drugs treatment, to achieve the target BP of less than 140/90 mmHg is fundamental to stroke prevention.³ A more recent meta-analysis have cast the doubt on the effectiveness of atenolol as a suitable drug for hypertensive patients, notably its use is associated with higher risk of cardiovascular mortality and stroke when compared with non beta-blockers.^4,5

There were a few trials that had demonstrated that angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARBs) reduced the risk of stroke by 28-32%.6-8 Summaries of the trials were given in Table 2.

High total cholesterol and LDL-cholesterol levels are associated with an increased risk of ischaemic stroke. Heart Protection Study (HPS),9  Scandinavian Simvastatin Survival Study (4S)10 using statins (HMG Co-A reductase inhibitors) in persons with coronary artery disease or risk factors showed a risk reduction in fatal and nonfatal stroke of 25%. Patients with diabetes are at increased risk for all forms of ischaemic stroke and are more likely to have hypertension and hyperlipidemia.³