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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Experience in a hypertension clinic attended by 591 patients over a 13-year period has shown marked changes in the pattern of use of hypotensive agents. Thiazides have been used throughout the period in almost all cases. Methyldopa was used for most patients for almost a decade. Since 1967 there has been a steady increase in the use of beta adrenergic blocking agents, and these are now used for over 60% of patients attending the clinic. Combination beta adrenergic blocking agents with peripheral vasilodators such as hydrallazine and prazosin have provided a very effective means of controlling the blood pressure in moderate and severe hypertension. Prazosin, a new peripheral vasodilator, has been used in the treatment of 295 patients. In most cases it has been used in combination with a thiazide diuretic and beta adrenergic blocking agent. Open studies have demonstrated that this is an effective hypot .ensive agent. Side effects are few and are counteracted by combination with a beta adrenergic blocking agent. Prazosin and hydrallazine are being compared in double-blind studies.
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PMID:Changing concepts in the management of hypertension. 24 Jan 12

A 55-year-old woman developed symptoms suggestive of hepatitis 12 weeks after first receiving methyldopa for hypertension. Liver biopsy showed chronic aggressive hepatitis with subacute hepatic necrosis. Methyldopa was discontinued, but after exhibiting transient clinical improvement, the patient's condition progressively deteriorated until she died of hepatic failure, in spite of therapy with massive doses of corticosteroids and other nonspecific measures. During the terminal stage, a considerable decrease in the size of the liver was observed. At autopsy, the liver was found to be small, shrunken, and scarred; histological sections demonstrated postnecrotic cirrhosis. Such a rapid and relentless progression of methyldopa-induced liver injury is undoubtedly rare, but it may be prevented by careful supervision of patients who exhibit liver function abnormalities early in the course of therapy.
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PMID:Methyldopa-induced liver injury. Rapid progression to fatal postnecrotic cirrhosis. 94

In 100 children with persistent hypertension seen over the past 5 1/2 years the commonest causes of hypertension were chronic glomerulonephritis, reflux nephropathy, coarctation of the aorta, and obstructive uropathy, accounting for some 70% of cases. 17 children have died, but in the remainder hypertension has been controlled by surgery, chronic haemodialysis, or by the use of pharmacological agents. Methyldopa was the commonest drug used, and the children appeared relatively resistant to the side effects of this and of other drugs, even when large doses were used. The improvment is the prognosis of severe hypertension in childhood indicated in this survey is largely due to the availability of chronic haemodialysis and transplantation for end-stage renal disease, but the advances in diagnositc methods and surgical techniques and the introduction of new drugs have also contributed.
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PMID:Analysis of 100 children with severe and persistent hypertension. 101 48

Administration of methyldopa (100 mg/kg, orally twice daily for a period of 3 days) to mongrel dogs produced significant reductions in blood pressure and heart rate. The hypotensive effect of the drug was due to a reduction in peripheral resistance. Methyldopa treatment also produced a significant decrease in coronary vascular resistance. Studies on the left ventricular function indicated that treatment with methyldopa does not compromise the ability of the myocardium to respond to an increased work load. Thus, the beneficial effect of this agent on the myocardial circulation, together with its lack of any detrimental effect on the cardiac function suggest that methyldopa may be an effective agent for the control of hypertension.
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PMID:Effect of methyldopa treatment on cardiac function and myocardial blood flow in mongrel dogs. 125 44

It is taken for granted that severe hypertension in pregnancy should be treated, although the principle has not been formally tested by properly controlled trials. There is less certainty about treating mild to moderate hypertension (140/90 to 169/109 mm Hg). The risk of chronic hypertension in pregnancy depends on that of superimposed preeclampsia, which must be prevented by control of the blood pressure if antihypertensive treatment is to be beneficial. There is not a priori reason why lowering the blood pressure should have this effect. Most of the trials of treatment have been too small to provide conclusive answers. Usually treatment has been started too late to give a realistic expectation of influencing the evolution of superimposed preeclampsia. However, the largest trial of the early use of methyldopa in women with mild chronic hypertension, showed clearly that treatment does not prevent the superimposition of preeclampsia. beta-Adrenergic blocking agents, if used from the second start of the trimester, are associated with a major risk of severe growth retardation and are therefore contraindicated. Methyldopa has the best safety record, which includes long-term follow-up to assess the development of children exposed to methyldopa in utero. The ineffectiveness of antihypertensive drugs in preventing or ameliorating preeclampsia needs to be contrasted with the consistent evidence for the effectiveness of antiplatelet therapy. This is consistent with the increasing evidence that preeclampsia is not primarily, or even necessarily, a hypertensive disease.
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PMID:Controlled trials of antihypertensive drugs in pregnancy. 182 49

Double-blind, crossover comparisons of methyldopa with placebo were performed in 16 patients with mild to moderate hypertension. Methyldopa (250 mg tid) for 14 days significantly reduced blood pressure, impaired card-sorting time and digital symbol substitution score, and caused trends for impairment of other psychometric tests. Effects of practice were greater than those of treatment on all tests other than card sorting, although no interaction between treatment and practice was seen. Continued dosage impairs psychometric performance, but practice effect is a major confounder. Simple crossover studies are inadequate for detecting moderate drug effects on intellectual performance.
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PMID:Effects of methyldopa on psychometric performance. 227 82

The authors report a case of toxic hepatitis in a woman of 22 years of age in the third trimester of her first pregnancy treated by methyldopa for hypertension of pregnancy which was diagnosed at 33 weeks of amenorrhoea. The prodromal symptoms were mild and consisted of nausea, vomiting and rise in temperature and this phase was associated with febrile jaundice without pruritus and it was only associated with coagulation disorders in the third stage of labour. This was a case of mixed cytolytic hepatitis (ASAT x 3N) and cholestasis (x 1.5N). The outcome was fatal. The patient died three days after delivery following haematemesis and renal failure as well as hepatic encephalopathy. The main diagnostic feature was acute hepatic stasis in spite of the absence of pruritus and the presence of a raised temperature after hematolytic, viral and obstructive causes had been eliminated. Histology confirmed that there was toxic hepatitis. This aetiology was suggested by the timing of the symptoms after MD (methyldopa) had been taken. Elkington described methyldopa hepato-toxicity in 1969. Fatal cases in the literature were in patients who were over 40 years of age. Methyldopa is used in pregnant women because of its safety as far as the fetus is concerned. Mechanism by which it causes toxic hepatitis is a combination of abnormal metabolism (the cytochrome P450 chain produces an antigen) and an immune reaction in response to this antigen and these explain why such severe and potentially fatal forms of the condition exist.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Fatal toxic hepatitis in pregnancy. A discussion of the role of methyldopa]. 232 42

The prevalence of hypertension in adult Nigerians is about 20% and hypertension remains a significant risk factor in cardiovascular morbidity and mortality. In Africans, hypertension carries a dismal prognosis, has a late clinical presentation and certain antihypertensives may be less effective. We therefore conducted a therapeutic audit in order to assess the initial cardiovascular risk profile of Nigerian patients as well as the safety and efficacy of different antihypertensive agents. A cross-sectional survey of 367 patients (M:F:2:1) modal age 25-44 years, mostly WHO II, enrolled in our clinic was undertaken. 56% had been on treatment for up to one year and 2% for longer than ten years. 12.5% had concomitant diabetes mellitus. Statistical analyses of drug efficacy were done by Spearman correlation and Analysis of Variance (ANOVA). The rank order of hypertensive efficacy was as follows: Thiazides (T) (r = 0.57, P less than 0.05), T + Methyldopa (M) (r = 0.91, P less than 0.001) T + M + Hydralazine (r = 0.92, P less than 0.001). Neither propranolol, nor frusemide showed significant overall efficacy. However, propranolol appeared efficacious in hypertensives with renal impairment. Postural dizziness was occasionally reported. Total mortality was 6% occurring mostly in the modal age group. Diabetic hypertensives had a 5 fold enhanced risk of a fatal outcome (X2 P less than 0.001). Our findings support a rational stepped care approach to pharmacotherapy of hypertension in black Africans, a cost-effectiveness analysis of common antihypertensives; it elucidates the associated adverse effects to patients, and draws attention to the lethality of concomitant hypertension and diabetes. Prospective large scale studies of the treatment of hypertension in Africans are required.
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PMID:A therapeutic audit in the management of hypertension in Nigerians. 260 27

When mean arterial pressure exceeds 140 mmHg (equivalent to 180/120), there is a significant risk of maternal cerebral vascular damage. Therefore it is recommended that blood pressures greater than 170/110 should be treated with urgency, aiming to maintain the blood pressure at all times at less than 170/110 but not lower than 130/90. Parenteral hydralazine is effective and safe therapy. Labetalol (intravenously or orally) appears to be as effective and as safe, and causes fewer troublesome side effects; however, clinical experience of its use is more limited, particularly in relation to its safety for the fetus and neonate. Delivery of the fetus is usually the definitive management of severe hypertension in pregnancy. However, this action may not reduce the blood pressure immediately. After initial treatment with rapid-acting agents, it is often advantageous to maintain control of arterial pressure with ongoing oral therapy (methyldopa, labetalol). In addition to the protective effect on the mother, such therapy may allow delivery of the fetus to be deferred; this should be considered only if the fetus is significantly premature (e.g., less than 34 weeks), there is no other evidence of maternal or fetal distress, and there can be meticulous monitoring of the maternal and fetal state proceeding to prompt delivery if deterioration occurs. The indications for treatment of mild or moderate hypertension in pregnancy are less clear. Severe hypertensive episodes can be reduced by several drugs (methyldopa, labetalol, beta-blockers). Methyldopa appears to reduce the small risk of mid-trimester abortions seen in association with early hypertension. Other benefits may be possible with other individual drugs; however, none of these have been found consistently in controlled studies to date. There seems, therefore, to be no definite indication for treatment of mild hypertension in pregnancy; treatment of moderate hypertension may be reasonable but its value is unproved at present. Antihypertensive drugs are valuable in pregnancy to reduce the risks directly due to elevated blood pressure. These drugs are not expected to affect the evolution of preeclampsia nor to treat the other complications of this condition.
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PMID:Antihypertensive drugs in pregnancy. 286 23

In the control of chronic disease no therapeutic regimen is successful unless it is complied with. A number of studies have indicated that compliance with tablet-taking may be as low as 40%. Patients with hypertension are frequently on a number of different anti-hypertensive agents, and if they have other chronic disorders they may take as many as 10 different drugs and up to 40 tablets per day. It is therefore not surprising that compliance is poor. To achieve compliance requires education of the patient, reduction in the number of drugs and simplification of the drug regimen. Methyldopa was used in a crossover study on a once- or twice-daily basis. Blood pressure was measured at the same time each day 2 hours after the morning dose. Compliance was assessed by tablet count and by blood pressure control, which was better on once-a-day therapy. Over a 6-week period 95% of medication was taken on the once-daily compared with 84% on the twice-daily regimen. In a subsequent study atenolol once per day replaced propranolol given 3 times per day. Blood pressure was lower on atenolol and tablet compliance was 94% compared with 74% on thrice-daily propranolol therapy. In addition, many patients admitted not taking the midday dose. The effect of dietary advice was then monitored by 24-hour urine electrolytes. When advice was given superficially by the doctor, urine sodium fell from 186 mmol/day to 165 mmol/day. When seen on one occasion by a dietitian and given diet sheets, it fell from 182 to 135 mmol/day. When seen at repeated visits by the dietitian and the advice modified according to sodium excretion, urine sodium excretion fell from 188 to 83 mmol/day. Supplemental oral potassium is often given as antihypertensive medication and up to 6 tablets per day may be administered. Compliance decreased as the number of tablets increased. Compliance was 92% on 1 tablet, 83% on 2 tablets, 68% on 3 tablets, 75% on 4 tablets (usually taken as 2 tablets twice a day) and 58% when on 6 tablets per day. The compliance with diuretic-taking was 96%. When given amiloride/hydrochlorothiazide the compliance was 93% and this elevated plasma potassium more than high dose supplemental potassium. In a recent study people on 3 or more drugs for blood pressure control were placed on a low salt diet and their drugs replaced with enalapril.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Compliance and the elderly hypertensive. 287 9


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