Makindo Medical Notes.com

Related Subjects: |Hypertension

Epidemiology

• An estimated 150,000 people have a stroke in the UK each year
• Stroke accounts for around 53,000 deaths each year in the UK
• Stroke is the third most common cause of death in England and Wales, after heart disease and cancer
• Stroke accounts for 9 per cent of all deaths in men and 13 per cent of deaths in women in the UK
• 450,000 people are severely disabled as a result of a stroke in England
• Direct cost of stroke to the NHS is estimated to be £2.8 billion. The cost to the wider economy is £1.8 billion. The informal care cost is £2.4 billion
• Stroke patients occupy around 20 per cent of all acute hospital beds and 25 per cent of long-term beds
• Stroke units save lives: for stroke patients, general wards have a 14% to 25% higher mortality rate than stroke units
• Each year over 130,000 people in England and Wales have a stroke. About 10,000 of these are under retirement age

Incidence/Prevalence

• Studies in South London show that Stroke incidence has been declining for some years
• Reduction in smoking, cholesterol, hypertension screening and treatment, antiplatelets, statins, blood pressure treatment
• Incidence in populations - per 100,000 is 556 in Minnesota, 406 in Copenhagen and 719 in China

Risk factors

• Non-modifiable - age, sex, race/ethnicity, hereditary, previous stroke
• Modifiable - HTN, smoking, DM, Hyperlipidaemia, Sickle cell disease, AF
• Potentially modifiable - Obesity, Physical inactivity, Alcohol/Drug abuse, hyperhomocysteinaemia, Hypercoagulability disorder, Hormone replacement therapy, Oral contraceptive, Carotid stenosis

Hypertension

• Seen in 60% at 60 years and 70% at 70 years
• Risk of both Ischaemic and Haemorrhagic stroke correlate BP
• Increase in 10 mmHg SBP ? 1.9 for stroke in men and 1.7 for women
• Isolated systolic hypertension is an independent risk

Lipids

• Cholesterol and LDL levels directly correlate with heart disease and HDL levels inversely.
• Cholesterol levels correlate carotid artery disease and atheroma
• Low cholesterol may increase the risk of haemorrhagic stroke

Diabetes Mellitus

• It affects both small and large vessels
• Diabetes appears to be increasing
• Independently Increases stroke risk by between 1.5-3.0
• Intensive treatment reduces microvascular (retinopathy, neuropathy, nephropathy) but not macrovascular complications such as stroke.
• Blood pressure control needs to be intensely aiming for 130/85 mmHg or lower.

Smoking

• Independent risk factor for stroke. Risk of about x 1.5
• Risk correlates the number of cigarettes smoked
• Accelerates atherosclerosis

Alcohol

• Increased haemorrhagic stroke correlates alcohol intake
• Ischaemic stroke may show a reduced risk for low alcohol intake and high for heavy intake
• Some studies have not shown any marked relationship

Low physical activity

• Some evidence that it may increase stroke risk

Hyperhomocystinaemia

• Homocysteine ? (needs B6) cystathionine ? cysteine
• Homocysteine ? (needs B12 and folate) methionine
• B6/B12 and folate deficiency can lead to ? Homocysteine
• ? Homocysteine may increase IHD, stroke, carotid disease
• No clear evidence of benefit with treatment

Oestrogen use

• Concerns over Oestogren containing OCP and HRT
• Evidence of risk with high dose older OCP medications
• No evidence with newer pills with doses < 50 mcg
• A meta-analysis showed? 2.75 in OCP users and ? 1.65 with low oestrogen
• Still this risk is very low in absolute terms and needs balanced with the indisputable stroke risk related to pregnancy.
• Postmenopausal HRT may increase stroke risk

Carotid disease

• Symptomatic disease has a 2-year stroke risk of 26% in medically treated patients
• Asymptomatic disease the risk of stroke is 1-3% per year in those with > 70% stenosis

TIA

• Strong predictors of subsequent stroke
• 6-month stroke rate of 17%
• 90-day stroke rate of 10% (1/2 of these within in 2 days)

Atrial fibrillation

• AF and Valvular heart disease risk x 20
• AF and Non-Valvular heart disease risk x 5

Myocardial disease

• Stroke risk correlates IHD, LVH and CCF

valvular disease

• Mitral stenosis, endocarditis and prosthetic valves increase stroke

Other cardiac risk factors

• PFO +r atrial septal aneurysm
• Aortic arch atheroma
• Spontaneous echo contrast in left atrium
• Mitral valve strands