CORONARY ARTERY DISEASE RISK FACTORS
n.b. For purposes of guiding management of dyslipidemias, NCEP
specifies a small list of risk factors as counting--See under
"Dyslipidemias" for
details. The NCEP recommends counting CAD risk factors among those in the
"major" category below, though sedentary lifestyle and
dyslipidemias in general aren't counted; HDL < 35 counts as a
risk factor, though; Also, HDL > 59 counts as a
"negative" risk factor, i.e. if it's there, you
subtract 1 from the count of risk factors
MAJOR (per JAMA 269:3015, 1993):
- Age (e.g., >45yo for men, >55yo for women unless
premature menopause w/o HRT)
- Family history (e.g., MI or sudden death at <55yo in
father or other 1st-degree male relative, or <65yo in
mother or other 1st-degree female relative)
- Smoking
- Hypertension
- Dyslipidemias (high
LDL, low HDL, high TC/HDL or LDL/HDL ratio--Click on link for details)
- Diabetes Mellitus
- Unknown whether glycemic control affects risk
- Raises risk more for women than for men (NEJM
332:1758, 1995-rvw)
- Sedentary lifestyle
OTHERS:
- High HDL (> 60mg/dl) is a
"negative" risk factor per NCEP (see under
"dyslipidemias")
- Obesity
- Traditionally considered a weak but significant
independent factor; may contribute secondarily
through effects on glucose metabolism, BP, etc.
- 115,000 women
enrolled in Nurses' Health study 30-55yo and free
of CV disease or Ca at enrollment followed for
16y. In multivariate analysis (adjusted for age,
tobacco consumption, menopausal status, use of
OCP's and postmenopausal HRT, and parental h/o MI
before age 60), the following results were
obtained (NEJM 333:677,
1995--abst):
- For all
women, RR of death during study interval
attained statistical significance only in
women with BMI > 32 (RR 1.5)
- For women
who never smoked, RR of death during
study interval attained statistical
significance in women from BMI 27 upward
(1.4 for BMI 27-28.9; 1.7 for BMI
29-31.9; 1.9 for BMI > 31.9)
- For women
who never smoked and had stable weight in
4y after intake, RR of death during study
interval attained statistical
significance in women from BMI 27 upward
(1.6 for BMI 27-28.9; 2.1 for BMI
29-31.9; 2.2 for BMI > 31.9)--in this
analysis, also adjusted for EtOH and
saturated fat intake and physical
activity.
- 44,702 women
enrolled in Nurses' Health Study 40-65yo and free
of CAD, CVA, and Ca at baseline followed for 8y.
(JAMA 280:1843--abst)
- WHR and
waist circumference were independently
associated with risk of CAD; adjustments
included adjustment for BMI
- Data from men in
the Framingham study who were examined biennially
over 30y. Baseline weight was significantly
correlated with mortality; including after
multivariate analysis (abstract didn't say what
factors were controlled for; Ann. Int. Med.
103:1006, 1985--abst)
- 3983 men with mean
age at entry of 30.8 years followed for 26y.
After adjustment for age and BP, BMI was a
significant predictor of onset of ischemic heart
disease. (Am. J. Cardiol 39:452, 1977--abst)
- 3y prospective
study of 29,000 US men age 40-75y at intake. BMI,
waist-hip ratio, and weight gain since age 21
were ass'd with increased incidence of CAD. RR
after adjustment for "other coronary risk
factors" was 1.72 (sig.) for men < 65yo
with BMI 25-28.9, 2.61 (sig.) for BMI 29-32.9,
and 3.4 (sig.) for BMI > 32.9, c/w men w/BMI
< 23. Abstract states that for men > 65yo,
association was "much weaker." (Am. J.
Epidemiol. 141:1117, 1995--abst)
- Hyperhomocysteinemia
- Severely increased levels in homocystinuria
associated with accelerated atherosclerosis
- Moderately increased concentrations of homocysteine
in men and women without homocystinuria ass'd with
increased incidence of atherosclerosis, CAD, CVA, and
overall mortality (though one case-control study of
140 pts with peripheral arterial disease and 14,776
controls followed over 9y failed to show an
independent effect after adjusting for other serum
markers--JAMA 285:2481, 2001)
- Hyperhomocysteinemia has also been associated with increased risk
for Osteoporotic Fractures in several
prospective cohort studies (NEJM 350:2033, 2004--JW; NEJM 350:2042,
2004--JW) and with Dementia (for the
latter, follow link for info on trials of homocysteine-lowering
therapy for Dementia)
- Folic acid, B6, and cardiovascular disease
- Folate necessary to convert homocysteine to
methionine
- Population studies of folate and B6 intake
- Oral supplements of folate (in doses of
0.4-5mg/d), pyridoxine, and cobalamin have
lowered moderately elevated plasma
homocysteine levels to nl in some men (Med
letter 39:12, 1997; BMJ 316:894, 1998--JW;
Am. J. Cardiol. 83:821, 1999--AFP)
- In a prospective trial of 5,056 adults 35-79yo without
known heart disease at baseline, serum and dietary folate
were poorly correlated, but over 15y of f/u, subjects in lowest serum
folate quartile had RR 1.69 for coronary
death comparted with those in highest
quartile. For women RR was 2.83. (JAMA 275:1893, ???)
- Folate & B6 intake (through diet or
supplements) were inversely ass'd with risk of
CAD dx in a 14y study of 80,000 women
participating in the Nurses' Health Study (JAMA
279:359, 1998--JW)
- Prospective trials of folate etc. supplementation
- Several randomized trials have confirmed that folate
supplementation (or folate + B12 supplementation) lowers serum
homocysteine concentrations (Med. Lett. 45:85, 2003)
- A combination "homocysteine-lowering" regimen (folic
acid 1mg, vit. B12 400ug, vit. B6 10mg QD) was ass'd with sig.
lower risk of (death, nonfatal MI, or repeat revascularization)
vs. placebo (15.4% vs. 22.8%; risk of death nonsig. lower--1.5%
vs. 2.8%) over mean f/u of 11mos in 553 post-angioplasty patients
(JAMA 288:973, 2002--abst)
- Folic acid 0.5mg PO QD was not
ass'd with any difference in a composite endpoint (mortality or
any of certain vascular events) c/w placebo in a 24mo randomized
trial in 593 pts with stable CAD. (J. Am. Coll. Cardiol.
41:2105, 2003--abst)
- 3680 pts with h/o ischemic CVA
and elevated homocysteine levels randomized to (folic acid 2.5mg/d
+ pyridoxine 25mg/d + cobalamin 0.4mg/d) vs. infinitesimal doses
of all 3; over mean 2y f/u, no sig. diff. between the group in
incidence of recurrence CVA, coronary events, or death.
(JAMA 291:565, 2004--JW)
- A combination of (folate,
B6, and B12 PO) vs. placebo was, after 6mos, ass'd with no
diff. in restenosis risk in a randomized trial in 636 pts s/p
successful PTCA (NEJM 350:2673, 2004--JW)
- In a study in 5,522 pts
randomized to (folic acid 2.5mg, vit. B6 50mg, and vit.
B12 1mg) vs. placebo; at 5y, there were no sig. diffs. in
(cardiovascular death, MI, or CVA) ("Heart Outcomes
Prevention Evaluation" study
("HOPE"); (NEJM 354:1567, 2006--JW)
- In a
meta-analysis of 12 randomized trials of folate
(0.5mg-15mg/d) vs. placebo, folate was associated with
sig. reduction in homocysteine levels but had no sig.
effect on incidence of CAD or CVA events or all-cause
mortality (JAMA 296:2720, 2006--JW)
- In a
study in 819 pts 50-70yo with serum homocysteine levels of
13umol/L or greater randomized to 0.8mg folic acid vs.
placebo QD, after 3y, the folic acid group had sig. slower
declines in information-processing speed ("FACIT"
Trial; Lancet 369:208, 2007--JW)
- In a study in 5,442 women > 40yo with CAD or CAD risk
factors randomized to a combination of (folate 2.5mg, vit.
b6 50mg, and vit. b12 1mg) QD vs. placebo, after mean 7y
f/u, there was no sig. diff. in incidence of (MI, CVA,
coronary revascularization, or cardiac death)
("Women's Antioxidant and Folic Acid Cardiovascular
Study" ("WAFACS") trial; JAMA 299:2027,
2008-JW)
- A case control study of 85 pairs of men with & w/o
CAD showed statistically significant increased risk of
CAD with all 3 of the following c/w those who had normal
parameters for at least 2; the association held up after
multivariate adjustment for LDL, HDL, and TG levels (JAMA
279:1955, 1998)
- High fasting plasma insulin
- High apolipoprotein B levels (the major structual protein of
LDL, IDL, and VLDL
- Small, dense LDL particles
- Depression
- In a prospective study of 3,700 men & women >
70yo with no known CAD at outset with median f/u x
4y, after adjustment for other risk factors, there
was a sig. increase in risk of CV death in depressed
pts only for men and only
for new depression (as opposed to depression of
remote onset) (Am. J. Cardiol. 81:988, 1998--JW)
- Personality/behavior
- "Type A" behavior significantly and
independently ass'd with risk for CAD in a
prospective study of 1,305 men assessed with the
"Type A Behavior" section of the MMPI-2
(Circ. 98:405, 1998--JW)
- Infections/Systemic inflammation (possible)
- C. pneumoniae has been identified in
atherosclerotic placques
- Some studies have shown a decrease in
risk of MI after abx tx (see under "Treatment of Stable CAD")
- Positive IgG Ab against Chlamydia
pneumoniae, Helicobacter pylori, HSV, and CMV
were not ass'd with increased risk of
cardiovascular events in a case-control study of
366 women, using data from the Women's Health
Study (Ann. Int. Med. 131:573, 1999--JW)
- C-Reactive Protein
- In a prospective trial of 5661 men 40-59
followed for 18y, CRP and Amyloid A
levels were sig. ass'd with risk for
coronary events; WBC, albumin levels,
plasma homocysteine levels, and titers
for H. pylori and Chlamydia pneumoniae
were not (BMJ 321:199, 2000--JW)
- C-Reactive Protein elevation sig. and
independently ass'd with risk of arterial
disease in a case-control study of 140
pts with peripheral arterial disease and
14,776 controls followed over 9y (JAMA
285:2481, 2001)
- Serum CRP levels were a more accurate predictor of risk
of cardiovascular events than LDL in an 8y cohort study of
28,000 middle-aged women (NEJM 347:155, 2002--JW)
- In a prospective study of 18,000 people followed for
mean 18y, pts in top 3rd of baseline CRP levels had sig.
higher risk for coronary events (OR 1.45) (NEJM 350:1387,
2004--JW)
- Specific treatment of C-Reactive
Protein levels to reduce cardiovascular risk
- In a study of 17,802 men >50yo and women >
60yo with no known DM or cardiovascular disease, LDL
< 130, and CRP 2mg/L or greater randomized to
rosuvastatin 20mg/d vs. placebo, after median 1.9y
f/u, rosuvastatin recipients had sig. lower incidence
of (unstable angina, MI, CVA, regascularization, or
cardiovascular death) (HR 0.56) and all-cause
mortality (HR 0.8); rosuvastatin group had sig. higher
incidence of new-onset DM ("JUPITER" trial;
NEJM 359:2195, 2008-JW)
- In a follow-up study of 15,548 pts from the JUPITER
cohort who had LDL and CRP levels checked after 1y,
there were sig. and independent reductions in LDL and
CRP among rosuvastatin recipients; rosuvastatin
recipients whose CRP levels fell < 2 mg/dL had sig.
greater reductions in adverse cardiovascular events
than those whose CRP levels remained 2 mg/dL or higher
(Lancet 373:1175, 2009-JW)
- In a follow-up analysis of the 5,695 JUPITER
subjects > 70yo, the primary outcome was reduced
with Rosuvastatin by 39% (sig.); so was all-cause
mortality (20% risk reduction) (data presented at
European Society of Cardiology conference, reported in
FP News 9/15/09 p. 1).
- Systemic Lupus Erythematosus is
associated with increase risk
- Glutathione peroxidase 1
- Found in high concentrations in
atherosclerotic placques.
- In a prospective study of 636 pts
with suspected CAD followed for median 4.7y, higher baseline blood GP1
levels were ass'd with lower rates of cardiovascular events, even adjusting
for other risk factors (NEJM 349:1605, 2003--JW)
- Epsilon-4 allele of apolipoprotein E (APOE4)
- Lipoprotein associated phospholipase A2
- An enzyme involved in repair of lipoproteins
- Independent predictor of coronary events in population studies (Med.
Lett. 45:83, 2003)
- Anemia
- In a population-based cohort study
of 14,420 people followed for avg. 6.1y, anemia (Hb < 13g/dL in men, <
12g/dL in women) was an independent predictor of development of CV disease
(HR 1.4 after adjustment for confounders) (JACC 40:27, 2002--JW)
- Recent cessation of NSAID use
(possible--click on link for details)
- Psoriasis (click on link for details)