The AHA Guidelines and Scientific Statements Handbook

(vip2019) #1

The AHA Guidelines and Scientifi c Statements Handbook


terol-lowering-therapy, especially for persons with
elevated triglycerides. (Level of Evidence: B)
Epidemiological evidence shows a strong inverse
association between high density lipoprotein choles-
terol (HDL-C) and CVD [1]. Whether a low HDL-C
directly promotes atherosclerosis or is only a marker
for other risk factors is uncertain. To date, only
limited clinical trial evidence suggests that raising
HDL-C may reduce risk for CVD [8]. (Level of Evi-
dence: C)
NCEP guidelines provide a classifi cation of total
cholesterol, LDL-C, non-HDL-C, and HDL-C as a
guide to therapeutic goals (Table 10.1).


Risk assessment: fi rst step in risk
management


The fi rst step in selection of cholesterol-lowering
therapy is to assess a person’s risk status. Risk assess-
ment requires measurement of LDL-C as part of
lipoprotein analysis and identifi cation of accompa-
nying risk determinants. Risk categories are defi ned
in Table 10.2. For patients without CVD or CHD


risk equivalents (defi ned in Table 10.2) and when 2+
risk factors are present, risk assessment by Framing-
ham risk scoring adds refi nement to absolute risk
assessment. It is preferable to do Framingham risk
scoring electronically (see http://www.nhlbi.nih.
gov/guidelines/cholesterol/index.htm [10-year risk
calculator {on-line version}]).

Table 10.1 Classifi cation of lipoprotein cholesterol levels


LDL cholesterol
< 100 Optimal
100–129 Above optimal/near optimal
130–159 Borderline high
160–189 High
≥ 190 Very high


Non-HDL-Cholesterol
< 130 Optimal
130–159 Above optimal/near optimal
160–189 Borderline high
190–220 High
≥ 220 Very high


Total cholesterol
< 200 Desirable
200–239 Borderline-high
≥ 240 High


HDL cholesterol
< 40 Low
≥ 60 High


Table 10.2 Risk categories for coronary heart disease

Risk category

Very high risk
Recent myocardial Infarction (acute coronary syndrome) or
CHDa + CHD risk equivalentsb
(or + multiple risk factorsc and/or metabolic syndromed)
High risk
CHD or CHD risk equivalents
(10-year risk for CHD >20%)
Moderately high risk
2 + risk factors
(10-year risk for CHD 10–20%)
Moderate risk
2 + risk factors
(10-year risk for CHD <10%)
Lower risk
0–1 risk factor

a CHD includes history of myocardial infarction, unstable angina, stable angina,
coronary artery procedures (angioplasty or by-pass surgery), or evidence of
clinically signifi cant myocardial ischemia.
b CHD risk equivalents include clinical manifestations of noncoronary forms of
atherosclerotic disease (peripheral arterial disease, abdominal aortic aneurysm,
and carotid artery disease [transient ischemic attacks or stroke of carotid origin
or >50% obstruction of a carotid artery]), diabetes, and 2+ risk factors with
10-year risk for hard CHD > 20%.
c Risk factors include cigarette smoking, hypertension (BP ≥ 140/90 mmHg or
on antihypertensive medication), low HDL cholesterol (<40 mg/dL), family
history of premature CHD (CHD in male fi rst degree relative <55 years; CHD
in female fi rst degree relative <65 years), and age (men ≥45 years; women ≥ 55
years).
d Metabolic syndrome is defi ned by 3 or more of the following risk factors:
abdominal obesity (waist circumference ≥102 cm in men or ≥88 cm in women),
elevated triglycerides (≥150 mg/dL), reduced HDL-C (<40 mg/dL in men or
<50 mg/dL in women), elevated blood pressure (≥130 mmHg systolic or
≥85 mmHg diastolic), plasma glucose ≥100 mg/dL, or on drug treatment for
any of these conditions.
e Almost all people with 0–1 risk factor have a 10-year risk <10%, and 10-year
risk assessment in people with 0–1 risk factor is thus not necessary.
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