الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
INTRODUCTION
Hypertension is one of the major risk factors for
coronary heart disease (CHD) according to epidemiologic
st-c1dies (Gordon & Kannel 1 971; Rosenman et al., 1 97 6). It
is perhaps the most readily treatable risk factor for
CHD, either by hygienic meas’.lres or, ·when these are not
eno-c1gh, by drug therapy (Culter 1 983).
Based on favorable ratio between blood pressure
lowering efficacy and known relative side ef~ects,diuretics
are established as the major dr”.Jgs ln the -creatment of
hypertension (Dustan et al., 1 974). Lately, the ·.1se of
diuretics has been reco~~ended also for the treatment
of ~he mildest =ar~s of hypertension, wit~ a view to
avoiding the complications -chat may develop later in
t~~e course of the disease ( C:Jl ter I 38 3). Yet a r..t::nber
of large intervention ~rials nave failed to show any
s”.Jbstantial benefit of blood pressure lowering on CHD
:r,orta:’.i ty. In fact, according to the recent ~~ltiple
Ris~ Factor Intervention Trial (C’iRFIT), C:!D :r.ortality
did ~at decrease af~er stepped-care treatme~t of hypertenslOTI,
counseling for c:.garette srr.cki:1g and dietary advice
for lowering blood ’ ~ ..... ~ c.’1o_._es .__e:co.l.. .:.evels as co:npareci -with
a siiilar population w~o received only their usual so~rces
o:: ’clealth care in the community. 7his is in marked contrast
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to the significant improvements in stroke, heart failure
and renal failure that have been reported as a result
of controlling high blood pressure (MRFIT 1 982). Because
CHD is rsponsible for the largest number of deaths among
patients with cardiovascular diseases, its lack of response
mainly
in
on
hypertension to
diuretic drugs
conventional therapy based
consti t.u.::e a major proble:r. in
cardiovas c:.1lar care (Ames 1 98 3) .
The lack of impact of blood pressure lowering on CHD
mortality has raised the question of whether the antihypertensive
agents commonly used may be offsec:ting the potential
benifit of such a reduction. The effect of di:.1retics
on blood lipids and lipoproteins have been cited as a probable
ca:.lse.
Schoenfield and Goldberger ( 1 9 64) reported that
serum cholesterol increased i:1 five of SlX cardiac patients
treated with the thiazide diuretic bendroflumenthiazide
and decreased when the drug was withdraw:1. This report
was not widely acknowleged or co:1firned untill 1 97 6 when
Arr.es a!1d 3ill have reported increases ir_ se::-:.:r!I cjolesterol
of i 1 mg/dl and seru:n ::riglycerides increases o:’ 34 :rcg/dl
ln patients treated with chlorthalido:1e. During the :’ollowlng
10 years, several workers studied the effects of
diuretics on blood lipids and lipoproteins. Altho:.1gh their
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results were not identical, yet the majority of these
workers reported an increase in total cholesterol, total
triglycerides, low density lipoprotein-cholesterol;
together with a slight decrease in hig~ de:-:.si ty lipoprotein-
cholesterol. These observations are of interest
since epidemiological studies indicate that total cholesterol
and low density lipoprotein-cholesterol concentra~
ions are positvely correlated with CHD risk; whereas,
high density lipoprotein-cholesterol is negatively correlated
with CHD risk (Gofman et al. 1 966, Slack 1 96 9,
Kannel et al. 1971, carlson & Bottiger 1972, Stone et
al. 1 974, ~!iller & !-Iiller 975, Castelli e~ al. 1 977,
and Gordon et al. 1 977). There has been a growing use
of i:1dices or ratios as indicatives of CHD risk, these
are: total cholesterol 1’ high density lipoprotein-cholestero:
a red low density lipoprote~n-choleste=ol / hig~
density :ipopro~ein-c~olesterol ratios (Castel~i e~ al.
1 977, Gordon et al. 1 977) .