PRESIDENT'S MESSAGE:

A SUMMARY OF MODERN TREATMENT OF HYPERTENSION

Recent data from the Egyptian National Hypertension Project, the first cross sectional national hypertension survey in a developing country, showed that 26.3% of adult Egyptians suffer from high blood pressure(1). The prevalence rate exceeds 50% in individuals above the age of 60 years. The management of such large number of patients should be within the domain of the general practitioner and should consist of the following components:

1. Establish the Presence of Hypertension: This requires repeated and accurate BP measurements. Transient elevations of BP can occur secondary to drug intake, emotions, painful stimuli, distended urinary bladder, cigarette smoking or white coat effect.

2. Assess the Need for Pharmacological Therapy: Unless there is a hypertensive emergency or urgency, life style modifications should be advised and patients followed initially for a period of few weeks to six months without drug intervention. Early initiation of pharmacological treatments is indicated in patients with target organ damage, e.g., left ventricular hypertrophy, optic fundus changes, proteinuria, coronary artery disease or when there are associated cardiovascular risk factors, e.g., diabetes mellitus, family history, hypercholesterolemia, cigarette smoking, etc.

3. Life Style Modification: Weight reduction, physical exercise, alcohol moderation, stress management, salt restriction, and other dietary measures are part of treatment strategy. Diet rich in fruits and vegetables and low in animal fat can reduce BP (2).

4. Drug Treatment: Treatment can be started by a diuretic, beta-adrenergic blocker, angiotensin converting enzyme inhibitor, a calcium antagonist or a combination. Choice of therapy is guided by patients hemodynamic, risk profile and associated diseases. Diuretics are the least expensive antihypertensive drugs, can be given to all patients, specially the elderly, obese, blacks, those with early renal impairment, systolic hypertension or heart failure. Beta adrenergic blockers are recommended to hypertensive patients with hyperkinetic circulation or associated coronary artery disease. Angiotensin converting enzyme inhibitors are given to diabetic hypertensives, hyperurecemia or heart failure. Calcium antagonists are recommended to coronary patients, elderly, systolic hypertension or in the presence of metabolic disturbances.

5. Follow-Up: Majority of antihypertensive drugs require ~8 weeks in order to achieve their maximum hypertensive action (3). Unless there is a need for its rapid lowering, BP should be checked after 2-4 weeks after intitiation of treatment and then every 4-8 weeks until control of BP is achieved. Then patients should be seen every 3-4 months regularly. If the patients did not tolerate the drug or if it fails to control hypertension after 6-8 weeks of administration, another agent from a different group is tried. It is recommended to start with a small dose and to increase the dose after 4-8 weeks or add another agent if BP control is not achieved. Lifestyle modification and control of other risk factors should be stressed.

REFERENCES

1. Ibrahim M. M., Rizk H., Appel L. J., et al. Hypertension Prevalence Awareness, Treatment and Control in Egypt: Results from the Egyptian Hypertension Project. Hypertension 2995; 26: 886-890

2. Appel L; I, Moore T.J., Obarzanek E., et al. Dietary intervention in Hypertension. N Eng. J Med. 1997; 336:1117-24.

3. Ibrahim M.M., Mossallam R. Clinical Evaluation of Atenolol in Hypertensive Patients. Circulation 19~l; 62: 1036-44.

M. Mohsen Ibrahim, MD
Professor and Chairman of the Cardiology
Department-Cairo University.
Principal Investigator the Egyptian National
Hypertension Project

Abstracts of World Literature
Long-term Effects on Plasma Lipids of Diet and
Drugs to Treat Hypertension
Riched H. Grimm, Jr, MD, Ph.D.; John M. Flack, MD, MpH; Gregory A. Grandits, MS; Palricia J. Elmer, Ph.D.; James D. Nealon, Ph.D.; Jeffrey A. Cuter, MD, MPH; Cora Lewis, MD; Robert McDonald, MD; James Schochnberger; MD, Jeremiah Stamler, MD; for the Treatment of Mild Hypertension Study (TOMHS)
Research Group

Objective - To compare long-term plasma lipid Changes among 6 antihypertensive treatment interventions for stage I (mild) hypertension.
Design - Multicenter, randomized, double-blind, parallel-group clinical trial.
Setting - Four academic clinical research units in the United States.
Participants - A total of 902 men and women, aged 45 to 69 years, with stage I diastolic hypertension (diastolic blood pressure <100 mmHg), recruited from 11914 persons screened in their communities.

Interventions - Participants were randomized to I of 6 treatment groups: (1) placebo, (2) B-blocker (acebutolol), (3) calcium antagonist (amlodipine), (4) diuretic (chlorthalidone), (5) a-antagonist (doxazosin), and (6) angiotension-converting enzyme inhibitor (enalapril). All groups received intensive lifestyle counseling to achieve weight loss, dietary sodium and alcohol reduction, and increased physical activity.

Main Outcomes Measures.- Changes in plasma total cholesterol, high-density lipoprotein (Hdl) cholesterol, low-density lipoprotein (I DL) cholesterol, and triglycerides from baseline to annual visits through 4 years.

Results - mean changes in all plasma lipids were favorable in all groups. The degree of weight loss with fat-modified diet and exercise was significantly related to favorable lipid changes. Significant differences (P<.01) among groups for aver-age changes during follow-up in each lipid were observed. Decreases in plasma total cholesterol and LDL cholesterol were greater with doxazosin and acebutolol (for plasma total cholesterol, 0.36 and 0.30 mmolIL [13.8 and 11.7 mgldL], respectively), less with chlorthalidone and placebo (0.12 and 0.13 mmolIL [4.5 and 5.1 mgldL], respectively). Decreases in triglycerides were greater with doxazosin and enalapril, least with acebutolol. Increases in HDL cholesterol were greater with enalapril and doxazosin, least with acebutolol. Significant relative increases in plasma total cholesterol with chlorthalidone compared with placebo at 12 months were no longer present at 24 months and beyond, when mean plasma total cholesterol for the chlorthalidone group fell below baseline. Analyses of participants continuing to receive chlorthalidone throughout the 4 years of follow-up indicated this was not due soley to an increasing percentage of participants changing or discontinuing use of medication during follow-up.

Conclusions - Weight loss with a fat-modified diet plus increased exercise produces favorable long-term effects on blood pressure and plasma lipid fractions of adults with stage I hypertension; blood pressure reduction is enhanced to a similar degree by addition of a drug from any one of 5 classes of antihypertensive medication. These drugs differ quantitatively in influencing the degree of long-term favorable effects on blood lipids obtained with nutritional-hygienic treatment.

(JAMA. 1996:275:15-19-1556)

Left Ventricular Hypertrophy in Hypertensive
Patients Is Associated With Abnormal Rate
Adaptation of QT Interval
Jagmeet P. Singh, MD, * Jim Johnston, Bsc, Peter
Sleight, MD, FRCS, FACC Rosemary Bird, Bsc,
Kathryn Ryder, MRCP, Dphil, George Hart, DM, FRCP
Oxford, England, United Kingdom

Objectives: This study to examine whether the responses of the QT interval to changes in the heart rate were altered in left ventricular hypertrophy (LVH).

Background: The QT interval has been shown to have a delayed adato sudden changes in heart rate in normal subjects. Abnormalities in the adaptation of the QT interval to changes in the RR interval may facilitate the development of ventricular arrhythmias.

Methods: Consecutive newly diagnosed hypertensive subjects, not taking any medications, were age and gender matched for LVH (n=2 1) versus no LVH (im-16). QT interval dynamics were analyzed under visual control using a validated algorithm with automatic QT measurements at the end of the T wave. A computerized Holter system was developed to study the QT interval response to changes in the RR interval. The adaptive response of the QT interval was measured as the ratio of the slope from 10% to 90% of the QT change relative to the RR interval change (dQT/dRR1O-90). Steady state adaptation was also studied as the percent shortening and lengthening of the QT interval during acceleration and deceleration of heart rate.

dQT/10-90 was increased in the LVH group compared with that in the control subjects during both acceleration (0.33+0.06 vs. 0.18+0.02, p--0.02) and deceleration phases (0.23+0.04vs. 0.16+0.02, p=0.03). In the LVH group, the percent lengthening of the QT interval was greater (7.6+0.7 vs. 5.1+0.2, p=0.03), whereas the percent shortening was not significantly different (5.7 1+0.Svs. 4.6+0.3, p=0.43), than that in control subjects.

Conclusions: The QT interval response to changes in the RR interval is rapid and exaggerated in LVH. These abnormalities of the QT interval response demonstrate that there are altered repolarization dynamics in-patients with LVH that may make them vulnerable to serious ventricular arrhythmias.

(J Am Coll Cardiol 1997; 29.778-84)

@1997 by the American College of Cardiology

Incidence of myocardial infarction in elderly men being
treated without antihypertensive drug
Juan Merlo, Jonas Ranstam, Hans Liedholm, Bo Hedblad,
Gunnar Lindberg, Ulf Lindblad, Sven-Olof Iscasson, Arne
Melander, Lennart Rastam

Objective - To analyze the association between use of antihypertensive treatment, diastolic blood pressure, and long term incidence of ischaemic cardiac events in elderly men.

Design - Population based cohort study. Baseline examination in 1982-3 and follow up for up to 10 years.
Setting-Malmo, Sweden.
Subjects - 484 randomly selected men born in 1914 and living in Malmo during 1982.

Main outcome measures - Observational comparisons of incidence rates and rate and hazard ratios of ischaemic cardiac events (myocardial infarction or death due to chronic ischaemic cardiac disease).

Results - The crude incidence rate of ischaemic cardiac events was higher in those subjects who were taking antihypertensive drugs than in those who were not (rate ratio 2.6, 95% confidence interval 1.7 to 3.9). After adjustment for potential confounders (differences in baseline smoking habits, blood pressure, time since diagnosis of hypertension, ischaemic or other cardiovascular disease, hypercholesterolemia, hypertriglyceridaemia, diabetes mellitus, obesity, and raised serum creatinine concentration) this rate was reduced but still raised (hazard ratio 1.9 (1.0 to 3.7). In men with diastolic blood pressure >90 mmHg, antihypertensive treatment was associated with a twofold increase in the incidence of ischaemic cardiac events (rate ratio 2.0 (1.1 to 3.6), which vanished after adjustment for potential confounders (hazard ratio 1.1 (0.5 to 2.6). In those subjects with diastolic blood pressure <90 mmHg, antihypertensive treatment was associated with fourfold increase in incidence (rate ratio 3.9 (2.1 to 7.1), which remained after adjustment for potential confounders (hazard ratio 3.8 (1.3 to 11.0).

Conclusion - Antihypertensive treatment may increase the risk of myocardial infarction in elderly men with treated diastolic blood pressures <90 mmHg.

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