MRC trial of treatment of mild hypertension: principal results. Medical Research Council Working Party.

The main aim of the trial was to determine whether drug treatment of mild hypertension (phase V diastolic pressure 90-109 mm Hg) reduced the rates of stroke, of death due to hypertension, and of coronary events in men and women aged 35-64 years. Subsidiary aims were: to compare the course of blood pressure in two groups, one taking bendrofluazide and one taking propranolol, and to compare the incidence of suspected adverse reactions to these two drugs. The study was single blind and based almost entirely in general practices; 17 354 patients were recruited, and 85 572 patient years of observation have accrued. Patients were randomly allocated at entry to take bendrofluazide or propranolol or placebo tablets. The primary results were as follows. The stroke rate was reduced on active treatment: 60 strokes occurred in the treated group and 109 in the placebo group, giving rates of 1.4 and 2.6 per 1000 patient years of observation respectively (p less than 0.01 on sequential analysis). Treatment made no difference, however, to the overall rates of coronary events: 222 events occurred on active treatment and 234 in the placebo group (5.2 and 5.5 per 1000 patient years respectively). The incidence of all cardiovascular events was reduced on active treatment: 286 events occurred in the treated group and 352 in the placebo group, giving rates of 6.7 and 8.2 per 1000 patient years respectively (p less than 0.05 on sequential analysis). For mortality from all causes treatment made no difference to the rates. There were 248 deaths in the treated group and 253 in the placebo group (rates 5.8 and 5.9 per 1000 patient years respectively). Several post hoc analyses of subgroup results were also performed but they require very cautious interpretation. The all cause mortality was reduced in men on active treatment (157 deaths versus 181 in the placebo group; 7.1 and 8.2 per 1000 patient years respectively) but increased in women on active treatment (91 deaths versus 72; 4.4 and 3.5 per 1000 patient years respectively). The difference between the sexes in their response to treatment was significant (p = 0.05). Comparison of the two active drugs showed that the reduction in stroke rate on bendrofluazide was greater than that on propranolol (p = 0.002). The stroke rate was reduced in both smokers and non-smokers taking bendrofluazide but only in non-smokers taking propranolol. This difference between the responses to the two drugs was significant (p = 0.03).(ABSTRACT TRUNCATED AT 400 WORDS)     

Randomised controlled trial of treatment for mild hypertension: design and pilot trial. Report of Medical Research Council Working Party on Mild to Moderate Hypertension.

A multicentre pilot trial to assess the feasibility of undertaking a full-scale national trial of treatment for mild to moderate hypertension has been performed and is being continued. By February 1977 over 1800 patients had entered the trial and some have been under observation for three years. The results so far show that the definitive trial is administratively and scientifically feasible and ethically justified.     

Bleomycin in advanced squamous cell carcinoma: a random controlled trial. Report of Medical Research Council Working Party on Bleomycin.

Bleomycin was compared with conventional cytotoxic drugs in the treatment of 70 patients with advanced squamous cell carcinoma; the primary deposit was in the head and neck in 50 patients and in the perineum or skin in 20. Thirty-four patients received bleomycin while 36 received other cytotoxic drugs. No significant difference was detected between the two groups either in the proportion showing tumour regression or in the survival rates. If bleomycin is to advance the treatment of squamous cell carcinoma it can be only in combination with other drugs or with radiotherapy.     

Ventricular extrasystoles during thiazide treatment: substudy of MRC mild hypertension trial.

One short term and one long term study of the relation between ventricular extrasystoles and thiazide treatment were carried out during the Medical Research Council''s mild hypertension trial. In the short term study 110 patients were randomly assigned to one of three treatment groups, bendrofluazide with or without potassium supplements, or placebo. They were studied before starting treatment and nine to 10 weeks later while still taking their randomly assigned drugs. No significant increase in the number of ventricular extrasystoles was associated with short term thiazide treatment, although serum potassium concentrations changed as expected. In the long term study 214 patients who had completed an average of two years'' treatment with randomly assigned bendrofluazide or a placebo were studied while continuing to take their trial tablets; the 214 included 20 people who had been randomised at entry to the bendrofluazide group and who had a subsequent history of hypokalaemia. These 20 patients were studied before and after being further randomised to two groups, one continuing treatment without change and one continuing with bendrofluazide and also taking potassium supplements. Counts of ventricular extrasystoles were significantly higher (p = 0.025) in those receiving long term thiazide treatment than in their controls; however, there was no significant association between the number of ventricular extrasystoles and serum potassium concentrations in this group, although the correlation between number of extrasystoles and serum urate concentrations was significant (p = 0.035). Pooled data for both studies showed a highly significant correlation between number of ventricular extrasystoles, and serum potassium concentrations (r = -0.185; p = 0.003), but the correlation with serum urate concentrations was of similar strength (r = 0.178; p = 0.004). These biochemical changes may be acting merely as markers of thiazide intake, and the explanation of the association between thiazide treatment and ventricular extrasystolic activity therefore remains uncertain.     

Is the cognitive function of older patients affected by antihypertensive treatment? Results from 54 months of the Medical Research Council's trial of hypertension in older adults.

OBJECTIVE--To establish whether initiation of treatment with diuretic or beta blocker is associated over 54 months with change in cognitive function. DESIGN--A cognitive substudy, nested within a randomised, placebo controlled, single blind trial. SETTING--226 general practices from the Medical Research Council''s general practice research framework. SUBJECTS--A subset of 2584 subjects sequentially recruited from among the 4396 participants aged 65-74 in the trial of treatment of hypertension in older adults. The 4396 subjects were randomised to receive diuretic, beta blocker, or placebo. Subjects had mean systolic pressures of 160-209 mm Hg and mean diastolic pressures <115 mm Hg during an eight week run in. OUTCOME MEASURES--The rate of change in paired associate learning test (PALT) and trail making test part A (TMT) scores (administered at entry and at 1, 9, 21, and 54 months) over time. RESULTS--There was no difference in the mean learning test coefficients (rate of change of score over time) between the three treatments: diuretic -0.31 (95% confidence interval -0.23 to -0.39), beta blocker -0.33 (-0.25 to -0.41), placebo -0.30, (-0.24 to -0.36). There was also no difference in the mean trail making coefficients (rate of change in time taken to complete over time) between the three groups: diuretic -2.73 (95% confidence interval -3.57 to -1.88), beta blocker -2.08 (-3.29 to -0.87), placebo -3.01, (-3.69 to -2.32). A less conservative protocol analysis confirmed this negative finding. CONCLUSION--Treating moderate hypertension in older people is unlikely to influence, for better or for worse, subsequent cognitive function.     

Phenylketonuria due to phenylalanine hydroxylase deficiency: an unfolding story. Medical Research Council Working Party on Phenylketonuria.

Efficient neonatal screening for phenylketonuria and the availability of complex diets for lifelong use have virtually eliminated severe mental handicap from the disease. Nevertheless, there remains a high risk of fetal damage in offspring of women with the disease, and the possibility that the diets themselves may be harmful cannot be excluded. Search for a preventive treatment for the disease has been greatly aided by advances in molecular genetics. For example, in mice modified liver cells have been implanted, which have not only corrected the phenylalanine defect but have remained healthy for the normal life span of the animal. Overall, however, prevention and treatment have not progressed as quickly as was hoped, and research and development must be pursued vigorously to take account of contemporary perceptions of the disorder.     

Course of blood pressure in mild hypertensives after withdrawal of long term antihypertensive treatment. Medical Research Council Working Party on Mild Hypertension.

A series of 1418 men and 1,347 women with mild hypertension (diastolic phase V 90-109 mm Hg) aged 35-64 who had either had long term antihypertensive treatment with bendrofluazide or propranolol or taken placebo tablets for a similar period were randomly allocated to groups in which their tablets were either stopped or continued. The course of blood pressure and of biochemical variables was followed up for two years. Mean blood pressures rose rapidly after the withdrawal of active treatment, and between nine months and one year after stopping treatment the antihypertensive effect had almost disappeared. The effect persisting longer than this, and possibly due to resetting of the baroreceptors or of other blood pressure control mechanisms, was very small, and as the rise in mean pressure was due to an upward movement in general distribution there was no evidence of a subgroup in whom these mechanisms had been permanently reset to a clinically important extent. After withdrawal of propranolol the rise in pressure was more rapid in younger than in older people. After stopping bendrofluazide pressure rose more rapidly in men who had had higher pressures before and during treatment; this effect was not seen in women. Disturbances in biochemical variables associated with drug treatment had largely resolved by the end of two years after withdrawal. Stopping placebo tablets made no consistent difference to blood pressure.     

Analysis and management of renal failure in fourth MRC myelomatosis trial. MRC working party on leukaemia in adults.

During March 1980 to February 1982, 73 out of 80 patients in renal failure admitted to the fourth MRC myelomatosis trial were managed by a planned policy of high fluid intake (greater than or equal to 3 1/24 h) in addition to receiving one of the two chemotherapeutic regimens being tested in the main trial. Patients were also randomised to receive either sodium bicarbonate to render their urine neutral or no supplement. Follow up continued till death or to April 1983. Of 49 patients who survived more than 100 days, 39 achieved reversal of their renal failure (18 complete, 21 partial). Recovery of renal function, as assessed by a fall in the serum creatinine concentration, was achieved even when light chain proteinuria persisted. Partial recovery of renal function was associated with prolonged useful life in several patients. In only 14 of the 80 patients studied was death directly attributable to renal failure. Survival of patients in the study was appreciably better than in equivalent groups of patients in other MRC trials in which less stringent policies of fluid intake were used. Patients randomised to receive alkali fared marginally better than the others, but the difference was not significant. These results show that in many cases patients with myelomatosis who develop renal failure may have this complication reversed by taking a high fluid intake. Furthermore, though light chain is an essential component of renal disease in these patients, other factors are also important and are accessible to treatment.     

Analysis of treatment in childhood leukaemia. I. Predisposition to methotrexate-induced neutropenia after craniospinal irradiation. Report to the Medical Research Council of the Working Party on Leukaemia in Childhood.

The degree of drug-induced neutropenia resulting from a controlled trial (UKALL I) of treatment in acute lymphoblastic leukaemia was analysed. The main agent associated with severe neutropenia was methotrexate, and methotrexate-induced neutropenia was significantly greater in patients who had received craniospinal irradiation. The synergistic toxic effect of irradiation followed by methotrexate treatment seems to have contributed to three of the five deaths which occurred in complete remission in this trial; all deaths in remission occurred in patients who had received central nervous system prophylaxis. Analysis of patients who subsequently relapsed compared with those still in remission after 18 months of treatment indicated that the former, on average, had slightly lower neutrophil counts. This suggests that the children who relapsed did not receive any less aggressive treatment than those who remained in remission.     

Effects of varying radiation schedule,cyclophosphamide treatment,and duration of treatment in acute lymphoblastic leukaemia. Report to the Medical Research Council by the Working Party on Leukaemia in Childhood.

In a multicentre trial of treatment for acute lymphoblastic leukaemia the effects of three types of central nervous system prophylaxis, the inclusion of cyclophosphamide, and the total duration of chemotherapy were assessed. A schedule with a high dose of spinal irradiation (2400 rads) without intrathecal methotrexate was inferior to schedules with some (1000 rads) or no spinal irradiation but with intrathecal methotrexate. The addition of cyclophosphamide 600 mg/m2 given intravenously every 12 weeks was of no benefit and was possibly deleterious. There was no advantage in adding four 12-week courses of chemotherapy after eight courses (total duration two years) had been given. Girls fared significantly better than boys, the difference being only partly due to the occurrence of testicular relapse.     

Treatment of acute lymphoblastic leukaemia: effect of variation in length of treatment on duration of remission. Report to the Medical Research Council by the Working Party on Leukaemia in Childhood.

Patients with acute lymphoblastic leukaemia (ALL) were allocated at random either to stop maintenance chemotherapy after six 12-week courses or continue with a further six. The main difference between the two groups was in the incidence of bone-marrow relapse within nine months after stopping treatment. Such relapses occurred less in older patients and those with higher leucocyte counts initially than in those who appeared to have the best prognosis--namely, those with typical low-count childhood ALL. No patient given prophylactic irradiation to cranium and spine combined with intrathecal methotrexate suffered meningeal relapses, whereas among those not given such prophylaxis the lack of benefit from continuing treatment was mainly attributable to meningeal relapses.     

Treatment of overt meningeal leukaemia in children: results of second MRC meningeal leukaemia trial.

After induction ofmeningeal remission by a course of intrathecal methotrexate patients were randomly allocated to receive either cranial irradiation or craniospinal irradiation. Patients being treated for their first meningeal relapse were randomised separately from those in their second or subsequent relapse. All eight patients in their first relapse who were given cranial irradiation alone developed further meningeal recurrence (median length of remission 15 weeks) compared with only two out of nine given craniospinal irradiation (median length of remission at least 99 weeks). Four of the nine patients given craniospinal irradiation were alive and without further meningeal relapse two and a half to four years after treatment. Craniospinal irradiation produced no such advantage for patients entering the trial in their second or subsequent meningeal relapse.     

Medical Research Council of Canada therapeutic trial of human growth hormone: first 5 years of therapy.

The Medical Research Council of Canada has initiated human growth hormone (hGH) therapy in 151 patients with documented complete hGH deficiency that was idiopathic in 76% of cases, secondary to craniopharyngioma (organic) in 17% and of varied cause in 7%. Approximately 50% of the patients with idiopathic disease had isolated hGH deficiency; during therapy thyroid deficiency developed in five patients and cortisol deficiency in three. A similar increase in mean height velocity occurred in the first treatment phase for patients less than 12 years old (0.93 plus or minus 0.30 cm/mo) and those 12 years and older (0.86 plus or minus 0.29 cm/mo). Although subsequent courses of hGH therapy yielded significantly diminished response in both age groups, this diminution was not progressive: the height velocity of the younger patients returned to 0.82 plus or minus 0.26 cm/ml in the fifth therapy phase. The mean height velocity attained at the optimal dosage (0.20 to 0.29 units/kg three times per week) for each age group did not differ significantly. Despite therapy being carried out for only 6 months of the year, normal increment ratios for height age and bone age against chronologic age were observed in the patients with idiopathic disease. In only four patients did treatment failure occur, and three of these were more than 20 years old. The addition of fluoxymesterone (10 mg/d) to the hGH therapeutic regimen (15 units/wk), when diminished response to hGH alone became evident, promoted an enhanced growth response in 9 of 11 older patients. These data indicate that age of the patient and dosage of hGH, but not diagnostic category, were important influences on the response to therapy. Younger patients responded best and maintained a higher mean growth velocity than older patients during intermittent hGH therapy