1、Cardiovascular Disease; Preventive Medicine 2005,David R. Rudy, M.D., M.P.H. Professor and ChairmanFamily and Preventive Medicine Chicago Medical School, RUMS,Atherosclerotic Vascular Disease,Risk Factors, Screening to Prevent,Atherosclerotic Disease,Coronary artery disease (CAD) Cerebrovascular dis
2、ease CVD) Peripheral vascular disease (PVD) Reno-vascular dis. and renal failure (CRF) hypertension,Coronary Artery Disease (CAD),1.5 million myocardial infarctions (MI)/year/US; 700,142 deaths from CAD 15% case fatality w/ acute MI; 30% case fatality w/ acute MIs as first indication of CAD; Risks=h
3、igh BP, dyslipidemia, physical inactivity, diabetes mellitus, age. (obesity) Smoking Genetics,Screening versus Prevention (1),Screening for CAD in general population is impractical (e.g. screening EKGs, stress testing, coronary angiograms) Resting EKGs not sensitive enough; EKG stress testing not se
4、nsitive enough in high risk populations; Thallium stress/EKG too sensitive in low risk populations; Coronary angiograms too risky and too expensive for screening,Screening versus Prevention (2),Primary (and secondary) prevention of CAD through control of controllable risk factors: Screening is for r
5、isk factors: imperfect but cost effective and tolerable,Risk factors for CAD (and other athero- sclerotic vascular dis:,Controllable: Hypertension, diabetes, dyslipidemia, smoking, C-reactive protein, (emotional stress); Uncontrollable: inheritance,Risk factors tend toward clusters: hypertension, di
6、abetes, dyslipidemia;,Metabolic syndrome X and insulin resistance (strong assoc. w/ obesity; strongly familial but remediable),Metabolic Syndrome X,Insulin resistance, hyperinsulinemia, incipient diabetes type II Hypertension Dyslipidemia: TC, LDLC, TGs, HDLC,Criteria for metabolic syndrome X: any 3
7、/5,1. Abdominal obesity: waist measurement 102 cm (40 in.) in men, 88 (35 in.)cm in women. 2. Hypertrigyceridemia: 150 mg/dL (1.69 mmol/L) 3. Low HDL cholesterol: 40 mg/dL (1.04 mmol/L); 50 mg/dL for women 4. “High” blood pressure: 130/85 mm Hg or hypertension under treatment 5. High fasting blood g
8、lucose: 110 mg/dL (6.1 mmol/L) or taking Rx for D/M Executive Summary of the Third Report of the NCEP etc. (ATP III). JAMA 2001; 285:2486-2496,Relationship between diabetes and hypertension,Diabetics have a 50% prevalence of hypertension (compare to 15-20% of US population); even when corrected for
9、weight Hypertensives have prevalence of glucose intolerance (abn BS patterns) = 15-18% (compare to 5-6% of adult US pop. w D/M) - a significantly larger percentage is assumed to have insulin resistance w/o glucose intolerance,Obesity, diabetes, hypertension and dyslipidemia,80%-90% of type II diabet
10、ics are obese Prevalence of obesity and of diabetes type II have risen in parallel since 1980. 33% increase in prevalence of D/M between 1990 and 1998,CAD: electrocardiogram: resting EKG as screen,ST depression, T wave inversion, Q waves, LVH may diagnose CAD. However, seldom CAD presents w/o sympto
11、ms; so EKG poor screen. E.g.in CAD occurs in 1-4 % of middle aged men w/o sympts; of those, 3%-15% developed symptomatic CAD over 5-15 years.,CAD: electrocardiogram: resting EKG as screen (2),1-4 % of middle aged men have CAD w/o symptoms (angiographic proof); of those, 3%-15% developed symptomatic
12、CAD over 5-15 years; Thus, at most, prevalence of CAD in asymptomatic males = 0.6% of middle aged men,CAD screening and EKG (3),EKG is neither very sensitive (only 29% of angiogram proven disease had ST,T or voltage changes) Nor specific - Nonspecific T common Resting EKG most useful for baseline an
13、d future comparison,CAD screening and EKG (4),Stress testing (EKG only) more sensitive and specific than resting EKG, but many false + (not specific enough Still, only 1-11% w/ abnormalities suffered acute MI or sudden death when followed over 4-13 years Addition of thallium scintigraphy scan proves
14、 more sensitive but less specific in low risk population.,CAD screening and EKG (5),Only 1-11% w/ abnormalities suffered acute MI or sudden death when followed over 13 years 0.045% (4/10,000) of resting EKGs will diagnose asymptomatic CAD,CAD screening and (EKG) - (7),Stress testing OK in higher ris
15、k states - e.g. out of shape middle aged ex-athletes before embarking on exercise program- usually EKG w/o, e.g. thallium Atypical chest pain w/ dyslipidemia, Obesity and/or hypertension, w/ thallium EKG is most useful in the acute situation,Best application for Scanned Stress Testing,Diagnosis of c
16、hest pain (I.e. not a screening situation),Criteria for CAD Screening I,The conditions must have a significant effect on the quality or quantity of life (YES). Acceptable methods of treatment must be available for the condition (YES). The condition must have an asymptomatic period during which detec
17、tion and treatment significantly reduce morbidity or mortality (YES). Treatment in the asymptomatic phase must yield a therapeutic result superior to that obtained by delaying treatment until symptoms appear (not settled).,Criteria for Screening II,Tests that are acceptable to patients must be avail
18、able at reasonable cost to detect the condition in the asymptomatic period. Corollary: Sensitivity and specificity must be appropriate for the risk status of the population being screened (NO and NO). The incidence of the condition must be sufficient to justify the cost of screening (YES).,Significa
19、nce of hypertension,Prevalence US said to be 58 million (20% of the entire population, adults and children); Leading risk factor for stroke; When neglected, presents as hypertensive heart disease (LVH, pulmonary edema), CAD Largely asymptomatic,Hypertension,Ranking risk factor for stroke CAD Renal F
20、ailure,Pathophysiology of essential hypertension,35 % Caucasians and most other groups hypertension characterized by salt/water retention; 65% African-Americans; majority of elderly 10% peripheral vascular resistance (PVR) (renin/angiotensin, catecholamines) 55% mixed PVR/salt retention) Hyperinsuli
21、nemia associated w/ volume dependent hypertension,Hyperinsulinemia associated w/ mineralo-corticoid, probable contributor to volume dependent hypertension,Salt/water retention driven hypertension responds to diuretics: thiazides loop diuretics (except in rising creatinine)- - and to salt restriction
22、 What portion of most groups hypertension have pure salt sensitivity? 35% Which portion of African-Americans hypertension? 67%,Salt Restriction: opportunity for primary prevention of hypertension (Other mainstays of Rx of hypertension: ACEIs and ACERBs, Ca+ channel blockers, blockers),Definitions of
23、 Hypertension (HTN),Three readings on separate occasions (140/90) to make the diagnosis, unless BP is found at 210/120,Htn in Children: 95th-99th percentiles*,Age group Newborns 30 d Infants 3-5 years 6-9 years 10-12 years 13-15 years 16-18 years,SBP/DBP, mm Hg 104-109 SBP 112-117/74-81 116-123/76-8
24、3 122-129/78-85 126-133/82-89 136-143/86-91 142-149/82-97,Physiologic Types of Hypertension,I Essential or Primary Hypertension (90-95% of all cases) II Secondary Hypertension: 5-10% of all cases (pheo, primary aldosteronism, renovascular)(Zollo: The Portable Internist. Hanley and Belfus/Philadelphi
25、a and Moseby/St. Louis 1995),Primary and secondary prevention HTN w/o drugs,Weight control to prevent HTN (and to prevent insulin resistance) Control sodium intake to prevent 1/3 HTN; useful adjunct in addtional 1/3 Stress management Control of other aggravating risk factors: e.g. smoking, dyslipide
26、mia,Isolated Systolic Hypertension (ISH: SBP140):,CVD risk More common in elderly; elderly more likely to have ISH; likely to be diuretic responsive.,Factors in primary prevention of Htn in high risk people:,-salt restriction-stress management-weight control,Implications of hypertension and of diabe
27、tes re/ kidneys:,Status of renal function,Major causes of chronic renal failure (not ESRD)* sub w/ Bakris:,Diabetes mellitus 31.0% Hypertension 27.0% Glomerulonephritis 14.0% Obstructive uropathy 5.7% Polycystic renal disease 3.6% Others 5.7% Unknown 13.0%,Diabetes: The Most Common Cause of ESRD,Pri
28、mary Diagnosis for Patients Who Start Dialysis,Glomerulonephritis,13%,Other,10%,United States Renal Data System. Annual data report. 2000.,No. of patients,Projection,95% CI,1984,1988,1992,1996,2000,2004,2008,0,100,200,300,400,500,600,700,r2=99.8%,243,524,281,355,520,240,No. of dialysis patients (tho
29、usands),Prevention of End Stage Renal Disease by BP and BS control,Tight control of blood sugar and of BP prevents ESRD in diabetics and hypertensives. Diabetes Control and Complications Trial Research Grp. Diabetes Care 1995 United Kingdom Prospective Diabetes Study 1998,Recommendations for screeni
30、ng for HTN (USPSTF, 1996):,“Screening for hypertension is recommended for all children and adults”, i.e. BPs on all visits,Secondary Prevention of Complications of D/M through control of BS, insulin resistance; UKPDS:,Metformin as good as S.U.s in BS control but MI mortality reduced by 39% w/ metfor
31、min (b/c reduces insulin) Hgb A1C controlled to 7.0 instead of 7.9; reduced retinopathy by 29%, nephropathy by 33%, and neuropathy by 40% (many now cut Hgb A1C 6.4,Dyslipidemia,Prevention and screening,ATP III criteria for lipid levels, ideal,LDL cholesterol 100mg/dL Total cholesterol 200mg/dL HDL c
32、holesterol 40 mg/dL (men) JAMA. 2001; 285:2487-2497,Lipid levels: when to apply diet,Total cholesterol: start diet 200 LDLC: diet for 160 mg/dL HDLC: diet at 5.1 males, 4.1 females, TG: diet for 150,Dietary goals:,Fats 30% total cal as: saturated simple Fiber 20-30 gm Protein 15% of total calories C
33、holesterol 200 mg/day,More liberal use of the HMG Co-enzyme A inhibitors (“statins”),Increasingly believed that people w/ mild to moderate risk factors benefit from “statins”; the foregoing includes even women and elderly (75 y.o.); That LDL should not exceed 100 mg/dL; That everyone should have a l
34、ipid profile every 5 years.,More liberal definition of risk status,From Framingham study, people w/ two risk factors should be treated as if they have already a diagnosis of CAD. People w/ diabetes alone to be treated as if they have already a diagnosis of CAD.,Significance of CRP Ridker : J.A.M.A.
35、2001; 285:2481-2485 Ridker: New Engl J Med 2004; 352:20-8,Marker of over exuberant inflammatory response, relevant in endothelial injury and repair; Highest quartile of CRP exhibits RR of 1.5 times expected risk for atherosclerotic disease,CRP continued,AS is a disease of endothelial defectiveness -
36、 failure causes rupture of plaques CRP levels, along with Total and Low Density Lipoprotein Cholesterol are reduced by statins,Recommendation for lipid screening (USPSTF) USPSTF: Guide to Clinical Preventive Services Second Edition. Williams and Wilkins 1996,“-periodic measurement of cholesterol for
37、 all men 35-65 and women 45-65- and it may also be clinically prudent for healthy men and women 65-75”,Primary prevention of dyslipidemia,Weight control Qualitative diet adjustments Exercise,Prevention of Stroke (1),First, control of risk factors: Htn, smoking, lipids, diabetes,Screening for stroke
38、susceptibility (2),Carotid stenosis of 75% carries 2% risk of stroke/year. ACAS study showed stroke reduction over a five year period to 5.8% - 4.8% from 10.5%, by preemptive carotid endarterectomy (a reduction of relative risk of 55% J.A.M.A. 1995; 273: 1421-28,Screening for stroke w/ carotid bruit (3),Doppler ultrasound yields 87% sensitivity and 91% specificity, for stenosis. Carotid angiogram is “gold standard”.,
