RESUMEN
In a double-blind randomized study, we evaluated the effects of 25 mg vs 50 mg of hydrochlorothiazide in 51 elderly patients (aged 68.9 +/- 7.0 years) with isolated systolic hypertension (blood pressure, 160 to 239 mm Hg systolic and less than 90 mm Hg diastolic). Dose levels could be increased to twice daily to control blood pressure. The reductions in blood pressure (25.4/6.8 mm Hg and 28.9/7.4 mm Hg) and proportion of patients in whom blood pressure was controlled (78% and 89%) were similar in the lower- and higher-dose groups during the titration phase. However, serum potassium level was reduced more in the higher-dosage (0.57 mmol/L) than the lower-dosage (0.17 mmol/L) group. There were no significant changes in blood pressure during a 24-week maintenance phase. No patient required withdrawal from the study because of adverse effects, and cognitive-behavioral function was well preserved. We conclude that hydrochlorothiazide is effective and well tolerated in older patients with isolated systolic hypertension, many of whom may be effectively treated with 25 mg of hydrochlorothiazide once daily.
Asunto(s)
Hidroclorotiazida/administración & dosificación , Hipertensión/tratamiento farmacológico , Anciano , Método Doble Ciego , Esquema de Medicación , Humanos , Hidroclorotiazida/efectos adversos , Hipertensión/sangre , Masculino , Persona de Mediana Edad , Potasio/sangreRESUMEN
We compared the efficacy and adverse effects of antihypertensive drug regimens in 690 men past age 60 with diastolic blood pressure 90-114 mm Hg and systolic blood pressure less than 240 mm Hg. They received either a low (25-50 mg) or high (50-100 mg) dose of hydrochlorothiazide daily. Of 644 patients who completed the hydrochlorothiazide titration, 375 (58.2%) were responders (diastolic blood pressure less than 90 and less than or equal to 5 mm Hg below baseline) and 92.8% of these completed a 6-month maintenance period. Blood pressure was reduced from 157.6/98.5 mm Hg by 18.3/9.5 mm Hg with low dose hydrochlorothiazide and by 20.4/9.6 mm Hg with high dose hydrochlorothiazide; more patients achieved goal blood pressure with the high dose. Whites and blacks responded equally. Serum potassium less than 3.5 mmol/l occurred in 104 of 321 (32.3%) of the high dose versus 62 of 333 (18.6%) of the low dose hydrochlorothiazide patients. The 269 nonresponders to hydrochlorothiazide were randomly assigned in a double-blind study to receive hydralazine, methyldopa, metoprolol, or reserpine in addition to hydrochlorothiazide; 79.2% responded to the addition of the second drug and 87.3% of these completed a 6-month maintenance phase. Overall, there were no significant efficacy differences among the step 2 regimens. We conclude that the lower dose of hydrochlorothiazide was nearly as effective as the higher dose, and the addition of a second drug was effective and generally well tolerated in elderly patients.
Asunto(s)
Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Anciano , Envejecimiento/fisiología , Antihipertensivos/efectos adversos , Presión Sanguínea/efectos de los fármacos , Diuréticos/uso terapéutico , Esquema de Medicación , Quimioterapia Combinada , Frecuencia Cardíaca , Humanos , Hidroclorotiazida/administración & dosificación , Hidroclorotiazida/efectos adversos , Hidroclorotiazida/uso terapéutico , Hipertensión/sangre , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Concentración Osmolar , Potasio/sangre , Grupos RacialesRESUMEN
This study was designed to determine whether blood pressure reduction, per se, causes adverse effects on cognitive and behavioral function in elderly hypertensive patients. Men with mild-to-moderate diastolic hypertension who had passed their 60th birthday were entered into the trial. After a placebo washout period, they were assigned in a randomized, double-blind manner to one of two groups receiving hydrochlorothiazide (either 25 mg once or twice daily or 50 mg once or twice daily). Responders entered a 1-year maintenance period. Nonresponders were randomly assigned to double-blind treatment with hydralazine, methyldopa, metoprolol, or reserpine added to the diuretic therapy. During the placebo and treatment periods, patients underwent a battery of psychometric tests designed to assess cognitive function, motor skills, memory, and affect. A separate questionnaire assessed the patient's ability to perform activities of daily living. A subset of patients blindly being treated with placebo received the same battery of tests as a control for practice effect. The results showed that there was similar improvement on the psychometric tests between those patients whose blood pressure was successfully reduced and the placebo-treated control group. Therefore, the practice effect did not obscure a true deterioration in function. There were no substantive differences between the lower and higher doses of diuretic or among the four drugs added to the diuretic, although there were qualitative differences in side effects. We conclude that blood pressure reduction, per se, does not adversely affect cognitive and behavioral function in elderly hypertensive patients and that antihypertensive treatment is safe and effective in these patients.
Asunto(s)
Antihipertensivos/uso terapéutico , Conducta/efectos de los fármacos , Cognición/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Actividades Cotidianas , Afecto/efectos de los fármacos , Anciano , Quimioterapia Combinada , Humanos , Hidroclorotiazida/uso terapéutico , Hipertensión/fisiopatología , Hipertensión/psicología , Masculino , Persona de Mediana Edad , PsicometríaRESUMEN
Cardiac arrhythmias are commonly seen in the everyday practice of medicine by the physician. Although certain arrhythmias may be suspected clinically, precise diagnosis is made by electrocardiographic recording of the abnormal rhythm. Once the arrhythmia has been recorded, the next steps are proper electrocardiographic diagnosis and selection of proper treatment. The specific mode of therapy and the speed with which it is delivered will depend not only on the type of arrhythmia, but also on the hemodynamic consequences of the rhythm abnormality on the patient's cardiovascular system. The purpose of this paper is to discuss the electrocardiographic criteria of common cardiac arrhythmias as well as current concepts regarding therapy.
Asunto(s)
Arritmias Cardíacas/diagnóstico , Electrocardiografía , Arritmias Cardíacas/tratamiento farmacológico , Arritmias Cardíacas/etiología , HumanosRESUMEN
To test the safety and reliability of atrial pacing as a conversion technique in patients with atrial flutter who are receiving digitalis therapy, atrial pacing conversion was attempted for 49 episodes of atrial flutter in 32 consecutive patients. All patients except one were receiving digitalis. To control ventricular rates most patients had received larger than usual therapeutic doses of digitalis glycoside before pacing. Fourteen of the 25 patients whose serum levels were measured had glycoside concentrations greater than 2 ng/ml. Before atrial pacing the mean atrial and ventricular rates were, respectively, 290 +/- 20.6 and 134 +/- 27.9/min (mean +/- standard deviation). Successful rhythm conversion was achieved on 48 occasions (98%) in 31 patients. One patient required transthoracic direct current synchronized countershock cardioversion. With atrial pacing, the atrial flutter rhythm reverted immediately to sinus mechanism in 23 instances, and there were 25 episodes of atrial fibrillation. Among those who experienced atrial fibrillation, the rhythm spontaneously reverted to sinus mechanism within 24 hours on 14 occasions; on 11 occasions; the rhythm reverted to atrial flutter and repeat pacing was required. Sinus mechanism was eventually established in all 31 patients.
Asunto(s)
Aleteo Atrial/terapia , Estimulación Cardíaca Artificial , Glicósidos Digitálicos/uso terapéutico , Cardioversión Eléctrica , Adulto , Anciano , Aleteo Atrial/tratamiento farmacológico , Glicósidos Digitálicos/administración & dosificación , Humanos , Masculino , Persona de Mediana EdadRESUMEN
One hundred and eight patients with initial diastolic blood pressure in the range of 100-124 mm Hg while taking hydrochlorothiazide were assigned randomly and double-blind to hydrochlorothiazide plus either bethanidine or guanethidine. The average reduction of the fifth and sixth months' diastolic blood pressure was 18.4 mm Hg for guanethidine and 13.6 mm Hg for bethanidine (P less than 0.01). The distribution of the individual values was such that 68.8% of guanethidine treated patients achieved a diastolic level below 90 mm Hg, compared to only 45.5% of the bethanidine treated group (P less than 0.025). The degree of orthostatic fall in blood pressure was greater with bethanidine than with guanethidine (P less than 0.05). The diurnal variation of blood pressure was slightly greater with bethanidine than with guanethidine. The results significantly favor guanethidine. This study failed to demonstrate that the shorter action of bethanidine confers significantly better control of blood pressure than the longer action of guanethidine.
Asunto(s)
Betanidina/uso terapéutico , Guanetidina/uso terapéutico , Guanidinas/uso terapéutico , Hipertensión/tratamiento farmacológico , Betanidina/administración & dosificación , Ensayos Clínicos como Asunto , Guanetidina/administración & dosificación , Humanos , Hidroclorotiazida/uso terapéutico , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
Previous observations of slowing of the heart rate after administration of atropine in doses smaller than 0.4 mg and recent reports of development of rhythm disorders in patients with acute myocardial infarction given atropine prompted us to evaluate systematically the effects of various doses of atropine (0.1 to 0.8 mg) on the response of the sinoatrial (S-A) and atrioventricular (A-V) nodes in healthy volunteers. The response of the S-A node to atropine was characteristically bimodal, slowing at smaller doses and accelerating at larger doses. In contrast, the A-V node showed acceleration of conduction in response to all doses of atropine used. A hypothesis based on current understanding of the electrophysiologic parameters governing impulse formation and impulse conduction is advanced to explain the apparent paradox in the S-A and A-V nodal responses to small doses of atropine. The results suggest the need for caution and continuous rhythm monitoring when giving atropine to patients with acute myocardial infarction.