High blood pressure. Causes, symptoms, treatments

Short-term management of macroprolactinomas with a new injectable form of bromocriptine.


The anti-hypertensive effects of atenolol (Tenormin) 50 mg, a potassium-sparing diuretic (half-strength Moduretic) comprising hydrochlorothiazide 25 mg plus 2.5 mg amiloride hydrochloride, and the 'free' combination of atenolol and diuretic were compared in elderly hypertensive patients aged 60-79 years. After a four-week run-in period on placebo, patients were randomly assigned, in a double-blind manner, to atenolol or diuretic treatment, each for four weeks. Thereafter patients were given the 'free' combination for a further four weeks and this treatment was continued for six months. Blood pressure and heart rate were measured after the patient had rested for five minutes supine and after two minutes standing. These blood pressure measurements were made at least 24 hours after the preceding dose using a Random Zero sphygmomanometer. Results from 26 of the 27 patients entered into the study showed an advantage for combination therapy combined with either atenolol or diuretic treatment alone. No significant difference was found between treatments in the frequency of supraventricular and ventricular ectopic beats occurring in six patients who underwent 24-hour ambulatory ECG monitoring. However, ectopic activity was reduced in some patients during beta-blocker treatment. Few adverse effects occurred with any treatment. Three patients withdrew during the placebo period and three withdrew while taking active treatment. This study has shown that the combination of atenolol, hydrochlorothiazide and amiloride hydrochloride is an effective, safe, well-tolerated antihypertensive drug regimen when used once daily in elderly hypertensive patients.

In 90 treatment-resistant hypertensive, 67% had plasma renin activity (PRA) below 0.5 nmol/l per hour. Of the 60 low-renin patients, 38 were studied on a fixed combination of amiloride and hydrochlorothiazide. Three weeks' treatment reduced blood pressure by 31/15 mmHg compared to placebo (P < or = 0.0001). Serum aldosterone and plasma renin activity increased substantially during active treatment. Through the subsequent 6-12 months of open treatment, seven patients (18%) showing an escape phenomenon had their high blood pressure effectively treated by extra amiloride. Of the 60 low-renin patients, eight had adrenal adenoma.

Medical treatment of the disease improved the dilation in all cases, preventing its potential complications. Regardless of the good outcome of our patients, periodic urologic follow-up is recommended in NDI patients.

After a run-in period of 8 weeks on a regimen of hydrochlorothiazide (HCT, median dosage 75 mg/day), patients with essential hypertension were randomly allocated to continued hydrochlorothiazide therapy (Group I) or additional treatment with amiloride (Group II, median dosage 15 mg/day, or 5 mg per 25 mg hydrochlorothiazide) for the following 12 weeks. Thereafter all the patients were changed to treatment with a fixed combination tablet containing 5 mg amiloride and 50 mg hydrochlorothiazide (Moduretic), keeping the thiazide dosage unchanged for an additional 12 weeks. In Group I patients there was no change in plasma potassium, total body potassium content or the renin-angiotensin-aldosterone system during the 12 weeks on HCT. When the treatment was changed to Moduretic, significant increases were found of 10% in plasma potassium and 3% in total body potassium content. No important stimulation of the renin-angiotensin-aldosterone system was found. In Group II patients addition of an average of 15 mg amiloride to the hydrochlorothiazide treatment led to significant increases in plasma potassium and total body potassium content of approximately 15% and 4%, respectively. There was also a significant increase in the plasma concentrations of renin, angiotensin II and aldosterone. Reducing the average dose of amiloride to 7.5 mg/day by use of Moduretic did not lead to decrease in plasma potassium or total body potassium content. Plasma concentrations of renin, angiotensin II, and aldosterone were decreased, but the individual changes varied markedly and no significant overall change was found.

Patients were referred from general and internal medicine practices following written invitations and included consecutively. Participants were examined and followed-up on an outpatient basis.

Of 6321 randomized patients, 1498 (23.7%) had ISH with a baseline mean BP of 173/88 mmHg in both treatment groups. Mean BP fell by 29/10 mmHg in the nifedipine and 30/10 mmHg in the diuretic group to a mean BP of 144/78 mmHg and 143/79 mmHg, respectively, at endpoint. The percentage of primary outcomes in patients with ISH was not significantly different between the two treatment groups (nifedipine GITS 6.0%, co-amilozide 6.6%). The number of ISH patients with composite secondary outcomes was 90 (12.2%) in the nifedipine GITS group and 110 (14.5%) in the co-amilozide group (not significant). The incidence rates of primary and secondary outcomes were similar in patients without ISH.