S2-167 Ethnicity & Disease, Volume 13, Spring 2003

Abstracts from the 18th Annual International

Interdisciplinary Conference on Hypertension and

Related Risk Factors in Ethnic Populations:

ISHIB2003—World Congress on Cardiovascular

Health: Preventing the Global Pandemic in

Developing Countries

Hypertension

001

BURDEN AND PATTERN OF HYPERTENSION IN

PREGNANT MOTHERS OF SUBSAHARAN ORIGIN

BL SALAKO; AA Odukogbe; O Olayemi; KS Adedapo;

CO Aimakhu.

DESIGN AND EVALUATION OF ``PARTNERSHIP

CARE MODEL'' IN CONTROL OF HYPERTENSION

E MOHAMMADI; H Ali Abedi; F Gofranipour; F Jalali;

A Kazemnejad, PhD.

Tarbiat Modarres University, Tehran, Iran; Medical Sciences

University, Esfahan, Iran; Medical Sciences University,

Babal, Iran.

One of the common goals of the World Hypertension League

(WHL) and WHO is the control of hypertension. Although each organization

has vast local and international investigations, they have yet

to gain significant success. More investigations are needed to find out

a precise and suitable way to reach this goal. Based on past investigations,

this study was done to design and evaluate a ‘‘partnership care

model’’ to control hypertension. Our study is a randomized clinical

trial with 75 patients in an intervention group and 70 in a control

group have been evaluated for a period of one year. The partnership

care model has been developed and designed by qualitative research

(Grounded theory method) by investigators. Patients’ outcomes in this

model included: systolic and diastolic blood pressure, cardiovascular

risk factors, clinical target organ damages (cardiac, cerebral and renal

complications), quality of life, mortality rate and patient compliance

with their therapeutic regimens. The results showed that the partnership

care model is effective to decreasing systolic and diastolic blood

pressure and increasing rate of controlled hypertension (based on criteria

of WHO/WHL) (1.8% vs 33.3% before and after intervention

respectively). This model also showed positive effects on health-related

quality of life (mean increase 3.2 score) and to reduce the body mass

index (mean decrease 1 kg/m2); anxiety (mean decrease 6 score); mitral

valve prolapse (mean decrease 4.3%); mortality rate (4.5%); decreasing

HDL level (mean increase 3); and compliance rates (mean

increase 3.2 score); and improving nutritional habits of the hypertensive

patients. We recommend that this model be used to control hypertension.

006

PREVALENCE, DETECTION, MANAGEMENT AND

CONTROL OF HYPERTENSION IN ASHANTI, WEST

AFRICA: DIFFERENCES BETWEEN SEMI-URBAN

AND RURAL AREAS

FP CAPPUCCIO1; L Emmett1; FB Micah3; SM Kerry1; RO

Phillips3 J Plange-Rhule123; JB Eastwood2.

Departments of 1Community Health Sciences and 2Renal

Medicine, St George’s Hospital Medical School, London (UK);

3Medicine, KATH, Kumasi (Ghana)

Background. Hypertension and stroke are emerging as important

threats to the health of adults in Africa. However, due to scarce resources

and healthcare provision, the detection of hypertension is still

haphazard and unreliable and the prevention of stroke lacking.

Objectives. To assess the prevalence, detection, management and

control of hypertension in rural and semi-urban areas of West Africa.

Design and Methods. 1,013 adult men (N5395) and women

(N5618) were screened as part of a community-based trial of health

promotion in the Ashanti region of Ghana. They were identified

through a household survey and population census of 16,965 inhabitants

in 12 villages (QJM 2002;95:445–50). 532 lived in semi-urban

and 481 in rural villages. The participants were seen in their villages.

They underwent measurements of height, weight and blood pressure

(OMRON HEM705CP) and answered a detailed questionnaire on

demography, socioeconomic status, health, diet, lifestyle and drug therapy.

Hypertension was defined as blood pressure .140/90 mm Hg or

being on drug therapy.

Results. Rural and semi-urban participants were comparable for age

(55 [SD 11] vs 55 [11] years). In semi-urban areas they were heavier

(BMI 22.3 [4.6] vs 19.8 [3.2] kg/m2; P,.001) and had higher blood

pressure (129/76 [26/14] vs 121/72 [25/13] mm Hg; P,0.001 for

both) than participants from rural areas. Hypertension prevalence was

28.7% (291/1013) overall. It was higher in semi-urban than rural

villages (32.9% [95% CI 28.9 to 36.9] vs 24.1% [20.3 to 27.9], or

1.54 [1.17 to 2.03], and increased with age. Detection, treatment and

control rates also tended to be higher in semi-urban (25.7%, 14.3%

and 3.4%) than in rural areas (16.4%, 6.9% and 1.7%), but they

appeared constant in the different age groups. Differences between

semi-urban and rural areas were not due to age, gender and body

weight.

Conclusions. Hypertension is common in West Africa and tends to

be more common in urbanized areas. Detection rates are suboptimal,

S2-169 Ethnicity & Disease, Volume 13, Spring 2003

ISHIB2003 ABSTRACTS

especially in rural areas and appropriate management is barely attained.

There is clearly an urgent need for preventive strategies for hypertension

control in West Africa.

008

PREVALENCE, DETECTION, MANAGEMENT AND

CONTROL OF HYPERTENSION IN ASHANTI, WEST

AFRICA: GENDER DIFFERENCES

FB MICAH1,3; FP Cappuccio1; L Emmett1; SM Kerry1; R

Martin-Peprah3; J Plange-Rhule123; JB Eastwood2.

Departments of 1Community Health Sciences and 2Renal

Medicine, St George’s Hospital Medical School, London (UK);

3Medicine, KATH, Kumasi (Ghana).

Background. Hypertension and stroke are emerging as important

threats to the health of adults in Africa. However, due to scarce resources

and healthcare provision, the detection of hypertension is still

haphazard and unreliable and the prevention of stroke lacking.

Objectives. To assess the prevalence, detection, management, and

control of hypertension in men and women in Ashanti, West Africa.

Design and Methods. 1,013 adult men (N5395) and women

(N5618) were screened as part of a community-based trial of health

promotion in the Ashanti region of Ghana. They were identified

through a household survey and population census of 16,965 inhabitants

in 12 villages (QJM 2002;95:445–50). 532 lived in semi-urban

and 481 in rural villages. The participants were seen in their villages.

They underwent measurements of height, weight and blood pressure

(OMRON HEM705CP) and answered a detailed questionnaire on

demography, socio economic status, health, diet, lifestyle and drug

therapy. Hypertension was defined as blood pressure .140/90 mm

Hg or being on drug therapy.

Results. Men and women were comparable for age (55 [SD 11] vs

55 [11] years). Women were heavier but shorter than men. Thus, BMI

was higher in women than men (21.6 [4.6] vs 20.2 [3.1] kg/m2;

P,.001). Diastolic, but not systolic, blood pressure was higher in men

(126/76 [25/14] vs 125/73 [27/13] mm Hg; P5.43/.008). Hypertension

prevalence was 28.7% (291/1013) overall. While it was comparable

in men and women (29.6% [95% CI: 25.1 to 34.1] vs 28.0%

[24.5 to 31.6], its detection rate was lower in men than in women

(14.5% vs 27.2%; P5.012; OR50.46 [0.25 to 0.85]). Treatment and

control rates were very low in both groups (7.7% and 3.4% vs 13.8%

and 2.3%, respectively). These gender differences were not due to age

and BMI.

Conclusions. Hypertension is common in West African men and

women. Detection rates are lower in men than women. Appropriate

management and control are barely attained in both men and women.

The reasons for the gender inequalities in detection rates are unknown.

013

MAINTAINING COMPARABILITY OF TREATMENT

GROUPS IN A COMMUNITY- BASED CLUSTER

RANDOMIZED INTERVENTION TRIAL TO REDUCE

BLOOD PRESSURE IN ASHANTI, GHANA

SM KERRY1; FP Cappuccio1; FB Micah1,3; L Emmett1;

J Plange-Rhule123; JB Eastwood2.

Departments of 1Community Health Sciences and 2Renal

Medicine, St George’s Hospital Medical School, London (UK);

3Medicine, KATH, Kumasi (Ghana).

Background. Cluster randomized trials (CRTs) have been used to

evaluate communicable disease interventions in developing countries,

but there is a lack of such trials involving health promotion in these

settings. In rural and semi-urban Ghana, health education takes place

at the village level, so cluster randomization is necessary to evaluate

such programs.

Objectives. To describe measures for maintaining comparability of

treatment groups in the design of a CRT.

Design and Methods. A household survey and population census

identified 16,965 inhabitants in 12 villages (6 rural, 6 semi-urban) in

the Ashanti region, Ghana (QJM 2002;95:445–50). Between 95–250

subjects from each village were invited to attend for screening. The

villagers were selected using stratified (for age and sex) random sampling

from a list of all inhabitants age 40–75 years. After baseline

measurements were completed in a pair of villages, the villages were

randomized to intervention or control arms, stratified for locality

(semi-urban or rural). The intervention was a health education program

to encourage dietary salt reduction. Primary outcomes of the

trial will be reduction in 24-hour sodium excretion and reduction in

systolic blood pressure (BP) at six months.

Results. 1,013 individuals agreed to take part in the study out of

1,896 invited (response rate 53%). Response rates varied between villages

(range 40 to 88%) but were similar in the two intervention

groups (51% vs 56%). The mean age (55 [SD 11] years vs 54 [11]

years) was similar in both groups. At baseline, systolic and diastolic

BP was similar in each intervention group (125/74 (27/14) vs 126/

75 (25/14) mm Hg). The percentage of participants adding salt to

their food at the table was similar in both groups (54% vs 50%).

Conclusion. By design, the age/sex structure of the two intervention

groups should be similar but there is a potential for bias to be introduced

by the low response rate. However the subjects were recruited

blind to treatment allocation thus removing the potential for such bias.

Initial comparisons of the groups showed no evidence of bias between

the groups.

020

AT1-RECEPTOR-BLOCKER (ARB) COMBINATION

WITH THIAZIDE: THE MOST EFFECTIVE

ANTIHYPERTENSIVE BITHERAPY FOR GLOBAL

CARDIOVASCULAR AND RENAL PROTECTION IN

BLACK HYPERTENSIVES?

A FOURNIER1; D Lemogoum2; G Amah3; JJ Pik4;

JP Degaute2; F Gueyffier.5

1Nephrology-Internal Medicine–CHU Amiens; 2Cardiology

Hopital Erasmus–Brussels (Belgium); 3CHU Lariboisiere–Paris;

4Internal Medicine Clermont de l’Oise;

5Hospices de Lyon (France).

For ALLHAT African Americans (AA), chlorthalidone is the preferred

initial blood pressure lowering (BPL) treatment vs amlodipine

S2-170 Ethnicity & Disease, Volume 13, Spring 2003

ISHIB2003 ABSTRACTS

because of lower heart failure (HF) risk and vs lisinopril because of

greater HF and stroke risk reduction. Second-step drug was atenolol,

clonidine or reserpine, which had BPL-synergy with chlorthalidone

and amlodipine, whereas the synergy was lacking with lisinopril, yielding

a 4 mm Hg higher SBP. ACEI as second-step drug would be,

however, as relevant as beta blockers, since in UKPDS, captopril and

atenolol granted the same BP and cardiovascular protection in association

with diuretics and that, in the AASK study, ramipril granted

better renal protection than metoprolol and amlodipine. Combination

of beta blocker or ACEI with a calcium channel blocker (CCB) would

be also relevant because they are BPL-synergistic and effective in treatment

of HF, a complication not well prevented by CCB, especially in

AA. No specific data on ARB in AA hypertensives are yet available,

but the LIFE trial found a greater BP-independent, selective strokeprotective-

effect (SPE) of losartan compared with atenolol, likely related

to AT2-mediated brain anti-ischemic effect, secondary to AIIstimulation.

Indeed ARB not only decreases AT1-deleterious vascular

effects as beta blockers and ACEI, but cancel AII-mediated renin secretion

inhibition.

This suggests that, in AA hypertensives, ARB may be the most

efficient drug to combine with thiazide for better preventing HF and

renal failure (vs CCB) and stroke (vs ACEI and beta blockers). This

justifies cost-effectiveness comparisons of these bitherapies in Black

hypertensives.

028

NATRIURETIC PEPTIDES MODULATE STRESSINDUCED

PRESSURE NATRIURESIS IN

AFRICAN-AMERICAN YOUTH

GK KAPUKU; GA Harshfield, RS Timm; ME Wilson;

L Mackey; D Gillis; HC Davis; L Carter; FA Treiber.

Georgia Prevention Institute, Medical College of Georgia,

Augusta, Georgia.

Impaired pressure-natriuresis is partially responsible for ethnic differences

in the development of essential hypertension (HTN) and associated

target organ damage. The aim of the study was to assess the

effects of the natriuretic peptides on stress-induced pressure natriuresis

among African-American youth. Subjects (N523; aged 15–18 years)

were brought into similar levels of sodium balance. Atrial natriuretic

peptide (ANP), brain natriuretic peptide (BNP) and sodium secretion

(UNAV) were measured hourly for two hours prior to, during and

following a one-hour video game stress period. Systolic BP (SBP) was

measured at 15-minute intervals. The effect of condition was signifi-

cant for SBP (P,.01). SBP increased significantly from baseline to

stress and decreased significantly during recovery. The effect of condition

was also significant for UNaV (P,.0001). The stress-induced

change in SBP was related to the level of ANP and BNP during stress.

Subjects with higher stress-induced ANP had higher sodium excretion

during stress. In addition, subjects with higher BNP during stress had

lower SBP during recovery (r50.43; P,.02). The results of this study

are consistent with the hypothesis that impairment of natriuretic peptide

regulation may be an important determinant of BP elevation.

035

HYPERTENSION IN RURAL GA: A STUDY OF FOUR

COMMUNITIES IN THE GA DISTRICT OF GHANA

J ADDO1; AGB Amoah1,2; K Koram3.

National Diabetes Management and Research Center, Korle Bu

Teaching Hospital, Korle Bu, Accra, Ghana; Department of

Medicine, University of Ghana Medical School, College of

Health Sciences, Accra, Ghana; Noguchi Memorial Institute for

Medical Research, College of Health Sciences, University of

Ghana, Legon, Ghana.

Objective. To determine the prevalence of hypertension in rural

subjects in the greater Accra region of Ghana.

Design. Cross-section cluster community study.

Setting. Four rural communities in the Ga district of Accra.

Subjects and methods. Adults, aged 18 years and older, in 4 communities

were sampled, and blood pressures were measured using standard

protocol. Weight and height were measured with subjects in light

clothing. Hypertension was defined as .140/90 mm Hg or current

anti-hypertensive treatment. Risk factors were ascertained with the aid

of a structured standardized questionnaire.

Results. A total of 363 subjects with a mean age of 42.3 years was

studied. 30% were males. The overall crude prevalence of hypertension

was 25.3%. Hypertension prevalence increased with age, obesity and

lower physical activity. Out of the 92 respondents diagnosed with

hypertension, only 26% (N524) had prior knowledge of their condition

and only 50% (N512) of these were on treatment. 16.7%

(N52) of hypertensives on treatment were found to be controlled.

Conclusions. Hypertension is relatively high in rural Accra. Control

and prevention programs may prove cost-effective in reducing hypertension-

associated morbidity and mortality.

036

CORRELATES OF HYPERTENSION IN ADULT

GHANAIANS

AGB AMOAH.

Department of Medicine, University of Ghana Medical School,

College of Health Science, Accra, Ghana.

Objectives. To determine the sociodemographic correlations of hypertension

in adult Ghanaians.

Design. 6,300 adults, aged 25 years and older, were selected by

random cluster sampling using electoral enumeration areas and listing

of adults.

Setting. Three communities (urban high class, urban low class residential

areas and rural area) in Greater Accra Region of Ghana.

Subjects and Methods. A total of 4731 (male-to-female ratio51:

1.5) participated, representing a response rate of 75%. The mean of

2 blood pressure readings taken with a mercury sphygmomanometer

after 10 min rest was used in analysis. Hypertension was defined as

.140/90 mm Hg or current anti-hypertensive treatment.

S2-171 Ethnicity & Disease, Volume 13, Spring 2003

ISHIB2003 ABSTRACTS

Normal BP (N53394) High BP (N51337)

Age (y)

BMI

42.1613.8

24.165.0

50.0615.3*

25.065.9*

Waist

WHR

SBP

DBP

84.4612.3

0.8560.07

124621

72612

88.7613.6*

0.8860.07*

143629*

81616*

* P,.001

Results. The crude prevalence of hypertension was 28.3%. In both

sexes, the prevalence of hypertension was highest in urban subjects

from low class residential areas and least in rural dwellers. The rates

of hypertension increased with age. Akan and Ga subjects had relatively

higher rates of hypertension compared to Ewes. Generally, the

rates of hypertension were high in the following subjects; those with

no formal education, those in sedentary occupations, those with no

leisure physical activity, those who drank alcohol, smokers and obese

subjects.

Conclusion. Hypertension is relatively common in urban and rural

Accra. Cardiovascular control and health promotion measures that address

lifestyle cardiovascular risk factors may prove beneficial.

040

LEFT VENTRICULAR DIASTOLIC FUNCTION IN

NIGERIAN HYPERTENSIVES

A ADEWOLE; A Akinyemi; D Adekola; O Okechukwu;

O Olulola; F Ayodele.

Background. Systemic hypertension has been associated with impaired

left Ventricular diastolic function. This is yet to be evaluated

in an African population. We sought to determine left ventricular

diastolic function in Nigerian hypertensives.

Methods. 184 subjects, with hypertension (97 females), and average

age 59.2 (SD 10.39) years were recruited for echocardiography. Each

subject underwent two-dimensional and Doppler echocardiography.

The parameters measured included left ventricular (LV) dimensions;

early and late atrioventricular (AV) flow velocities (E and A wave respectively);

E/A ratio, deceleration time (DT), systolic (S), diastolic

(D) and retrograde (R) pulmonary venous flow velocities; S/D ratio.

Results.

Parameter Mean (SD)

E (m/s)

A (m/s)

E/A

S (m/s)

D (m/s)

S/D

DT (msec)

0.63 (0.191)

0.67 (0.188)

1.03 (0.506)

0.49 (0.237)

0.45 (0.190)

1.15 (0.505)

221 (58.6)

There were no differences in the parameter between the sexes.

Conclusion. There is no gender difference in the parameters of left

ventricular diastolic function in Nigerian hypertensives. Comparison

of the parameters of left ventricular function with normal controls will

be presented at ISIB 2003.

041

CENTRAL AND PERIPHERAL

MALADAPTATIONS ASSOCIATED WITH

SALT-INDUCED HYPERTENSION

MA BAYORA; AA Ganafa; N Emmet; D Eatman; RR Socci;

ILFridie; IA Abukhalaf.

Morehouse School of Medicine, Atlanta, GA USA.

Hypertension is a recognized risk factor for organ damage including

changes in blood vessel morphology. Earlier studies using the Dahl

salt-sensitive (SS) rat have demonstrated vascular remodeling of the

mesenteric, renal and cerebral arteries. Here, we examined factors associated

with salt-induced vascular dysfunction and renal damage.

Male Dahl SS rats were fed either high salt (8%NaCl, HS) or low

salt (0.3%NaCl, LS) diet for 3–4 weeks. Mean arterial pressure (MAP)

and heart rate were measured weekly. Magnetic resonance imaging

(MRI) of the brain and regional blood flows were determined. Plasma

isoprostane, nitric oxide (NO), prostacyclin, and thromboxane A2

(TXA2) were determined by enzyme immunoassay. Plasma and kidney

GSH and GSSG were analyzed by HPLC. Kidneys were prepared and

stained for histology. Reactivity of mesenteric arteries was assessed in

vessel chambers.

HS increased MAP, isoprostane and TXA2 and decreased the GSH:

GSSG ratio, NO and prostacyclin. Renal and aortic blood flow was

decreased and vascular resistance was increased. MRI scans, in the HS

group, showed white matter hyper intensity. Glomeruli from the HS

were found to be sclerotic and exhibited severe fibrinoid necrosis.Mesenteric

arteries from the HS group had reduced lumen diameter, increased

wall thickness and reduced vasodilatory response to acetylcholine.

These studies suggest a strong correlation between oxidative stress

and the vascular and renal maladaptations associated with salt-induced

hypertension.

052

NATURAL VITAMIN-RICH PALM OIL ATTENUATES

THE PROGRESSION OF SALT-INDUCED

HYPERTENSION

AA GANAFA; IA Abukhalaf; SW Sahlu; D Eatman;

N Silvestrov; MA Bayorh.

Morehouse School of Medicine, Atlanta, GA USA.

The pathogenesis of hypertension in Dahl salt-sensitive (SS) rats,

fed a high salt (HS) diet has been associated with endothelial dysfunction

and oxidative stress. In our previous studies, palm oil (PO)

reduced oxidative stress-induced hypertension in normal rats. Here,