Benefit classification.
Category I: Confirmed validity, expert consensus; required!
Category IIa: conflicting evidence, but tends to be effective, less consensus among experts; accept as good.
Category IIb: conflicting evidence, but perhaps valid, less consensus; may try.
Category III: proven ineffective, expert consensus; save money and avoid incurring side effects.
Levels of recommendation for treatment or screening.
Class A: recommendation based on more adequate and strong evidence.
Grade B: recommendation based on insufficient and/or insufficiently strong evidence.
Grade C: Recommended as a consensus in the field, although there is no sufficient and strong evidence.
I. Recommendations for risk factors that are not generally amenable to intervention
Knowledge of family history of the disease can help to understand whether an individual is at increased risk of stroke (Class IIa; Level A).
Genetic screening for the purpose of stroke prevention is not recommended for individuals who have never had a stroke (Class III; Level C)
genetic counselling is recommended for patients with rare genetic causes of stroke (Class IIb; Level C)
Although it may be reasonable to treat certain genetic disorders that predispose to stroke (e.g., enzyme replacement therapy for Fabry disease), these treatments have not been shown to reduce stroke incidence and their effectiveness is unknown (Class IIb; Level C).
Genetic screening to assess the risk of drug-related myopathy is not recommended before taking statin therapy at this stage (Class III; Level C).
screening for unruptured intracranial aneurysms using non-invasive methods is not recommended for other members when only 1 first-degree relative in the family has a subarachnoid hemorrhage or intracranial aneurysm (Class III; Level C)
Screening for intracranial aneurysms by noninvasive methods may be reasonable when two or more first-degree relatives in the family have subarachnoid hemorrhage or intracranial aneurysms (Class IIb; Level C)
Carriers of Mendelian genetic variants (note: abnormal mutations at a single locus on the DNA molecule of the genetic material) with concomitant aneurysms are not recommended for screening for intracranial aneurysms in general (Class III; Level C).
Patients with autosomal dominant polycystic kidney disease, or more than one first-degree relative with autosomal dominant polycystic kidney disease who have subarachnoid hemorrhage and/or intracranial aneurysms, may be screened for unruptured intracranial aneurysms using a non-invasive test (Class IIb; Level C)
Patients with cervical fibromuscular dysplasia may be considered for screening for non-invasive unruptured intracranial aneurysms (Class IIb; Level C).
Pharmacogenetic findings are not recommended at this stage as a basis for prescribing doses of vitamin K antagonists (note: e.g., warfarin tablets) (Class III; Level C).
II. Recommendations for well-documented and intervenable risk factors
(i) Hypertension
Recommendations for regular blood pressure testing and control of blood pressure through lifestyle modification and medication (Class I; Level A), as recommended by JNC7 (American National Committee on Hypertension report7, see table below).
Systolic blood pressure (commonly referred to as high pressure) should be controlled below 140 mmHg and diastolic blood pressure (commonly referred to as low pressure) below 90 mmHg to reduce the risk of stroke and cardiovascular disease (Class I; Level A). In hypertensive patients with diabetes mellitus or kidney disease, the goal of blood pressure lowering is below 130/80 mmHg (Class I; Level A).
Normotensive: systolic blood pressure <120, and diastolic blood pressure <80, without the need for antihypertensive drugs.
Pre-hypertension: systolic blood pressure 120-139, or diastolic blood pressure 80-89; no need for treatment if no high-risk status*, or medication if high-risk status exists.
1, stage hypertension: systolic blood pressure 140-159, or diastolic blood pressure 90-99; without high-risk status, generally can take thiazide diuretics, other can consider angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), beta-blockers (BB), calcium channel blockers (CCB), or a combination of drugs; the presence of high-risk status, should take high-risk status, and use diuretics, ACEI, ARB, BB, CCB and other antihypertensive drugs as needed.
2, stage hypertension: systolic blood pressure ≥ 160, or diastolic blood pressure ≥ 100; no high-risk status, generally available 2 antihypertensive drugs in combination (commonly used thiazide diuretics, combined with ACEI, ARB, BB, or CCB); the presence of high-risk status, should be treated with high-risk status, and choose diuretics, ACEI, ARB, BB, or CCB as needed.
Description.
High-risk status: including ① congestive heart failure; ② myocardial infarction; ③ diabetes mellitus; ④ chronic renal insufficiency; and ⑤ previous stroke.
Lifestyle modifications: (i) weight loss in overweight individuals; (ii) limiting alcohol consumption; (iii) increasing aerobic exercise (30-45 minutes per day); (iv) reducing salt intake (<2.34 g per day); (v) maintaining adequate potassium intake (>120 mmol per day); (vi) smoking cessation; and (vii) healthy diet (more fruits and vegetables, low-fat dairy products; reduced saturated fat and total fat).
In patients with postural hypotension, caution should be exercised when starting a combination of antihypertensive drugs.
(ii) Smoking
The risk of stroke in smokers is approximately twice that of nonsmokers.
Based on the consistent and overwhelming evidence obtained from epidemiological studies of the strong association between smoking and ischemic stroke and subarachnoid hemorrhage, it is recommended that nonsmokers avoid smoking and smokers quit (Class I/Class B).
Although there is a lack of evidence whether avoiding smoking environments (“secondhand smoke”) reduces stroke incidence, epidemiological studies suggest that smoking “secondhand smoke” increases stroke risk, while avoiding “secondhand smoke “However, according to epidemiological studies, secondhand smoke increases the risk of stroke, while avoiding secondhand smoke reduces the risk of other cardiovascular diseases. Therefore, avoidance of “secondhand smoke” is reasonable (Class IIa/Class C).
A combination of techniques including counseling, nicotine replacement therapy, and oral smoking cessation medications may be beneficial as part of an overall smoking cessation strategy. Each patient’s smoking status should be understood and addressed during the consultation (Class I/Level B).
(iii) Diabetes mellitus
Blood pressure control should be part of a comprehensive cardiovascular risk reduction program (Class I/Level A), regardless of type I or type 2 diabetes, in accordance with the contents of the JNC7 guidelines (Exhibit 1).
For adults with diabetes, treatment of hypertension with an angiotensin-converting enzyme inhibitor (ACEI) or an angiotensin receptor blocker (ARB) is beneficial (Class I/Level A).
in adults with diabetes, especially those with coexisting other risk factors, statin lipid-lowering agents are recommended to reduce the risk of first stroke (Class I/Class A).
for patients with diabetes, consider a beta (fibrate) lipid-lowering agent alone (note: without concomitant statin lipid-lowering agents) to reduce the risk of stroke (class IIb/class B)
In patients with diabetes who are taking a statin lipid-lowering agent, the addition of a fibrate lipid-lowering agent does not further reduce the risk of stroke (Class III/Grade B).
In patients with diabetes mellitus, the effect of aspirin in reducing stroke risk has not been statistically proven; however, its use may be justified in patients with a high risk of cardiovascular disease (refer to the relevant section on aspirin) (Class IIb/Grade B).
(iv) Dyslipidemia
(ii) For patients with coronary artery disease, or those with high risk of cardiovascular disease such as diabetes, statin lipid-lowering agents are recommended on top of lifestyle modification to bring low-density lipoprotein cholesterol (LDL-C) up to the standards recommended by NCEP (Note: National Cholesterol Education Program) guidelines (Class I/Grade A).
Patients with hypertriglyceridemia may be considered for drugs such as fibrates and gemfibrozil, but their effectiveness in ischemic stroke prevention has not been demonstrated (Class IIb/Class C).
Niacin may be considered for those with low high-density lipoprotein cholesterol (HDL-C) or increased lipoprotein(a) [Lp(a)], but its effectiveness in preventing ischemic stroke has not been demonstrated (Class IIb/Grade C).
Other lipid-lowering agents such as fibrates, gemfibrozil, bile acid chelators, niacin, and ezetimibe may be considered for those who fail to achieve their lipid-lowering goals on statin lipid-lowering agents or who cannot tolerate these agents, but their effectiveness in reducing stroke risk has not been demonstrated (Class IIb/Grade C).