A comparison of selected antihypertensive medications in essential hypertensive patients

Hypertension affects a great number of the American adult population. Uncontrolled hypertension may lead to congestive heart failure, kidney failure, myocardial infarction and other serious events. Many of the people treated for an elevated blood pressure are not adequately controlled. The present study was conducted to compare the antihypertensive effects of two commonly prescribed medications: hydrochlorothiazide and methyldopa. These drugs were examined in varying doses when given alone or in combination with each other. The effect of variables such as race, age, weight, height and dose were also examined. Not only was each variable correlated to the decrease in blood pressure, but so were the interactions of these variables with each other. This study was a retrospective chart review conducted in a short term, large, general hospital. Only patients with essential hypertension who were discharged from the hospital between July 1, 1972, and December 31, 1973, were included in the study. Also, all patients in the study were in the hospital for at least three days, were males and received only specified medications for treatment of their hypertension. These patients had not received any antihypertensive medications for at least one month prior to their admission into the hospital and their blood pressures were elevated above 140 mm Hg systolic and/or 90 mm Hg diastolic upon entering the hospital. All blood pressures documented, drugs, other diagnoses and specified laboratory values were recorded. A total of 182 of 748 patients whose medical histories were reviewed met the above criteria and were included in the study. The blood pressure data recorded from the charts showed a significant interaction between hydrochlorothiazide and the decrease in blood pressure. A stronger interaction was seen when hydrochlorothiazide and high dosage were correlated with a decrease in blood pressure. The strongest effect was seen with the interaction of hydrochlorothiazide, high dosage and greater number of days on the drug regimen. No significant difference in lowering blood pressure was found between the different combinations of methyldopa and hydrochlorothiazide. In fact, none of the combinations of the two drugs were found to be as effective as hydrochlorothiazide in lowering blood pressure. Also, there was no significant interaction between methyldopa and high dose and a decrease in blood pressure. It was also found that non-white patients responded with a greater decrease in blood pressure than did the white patients. This study pointed out the effectiveness of hydrochlorothiazide as an antihypertensive agent. Surprisingly, this study found hydrochlorothiazide to be more effective in lowering blood pressure than methyldopa or any combination of the two drugs. This study pointed out the need for the re-evaluation of medical management of hypertension.