Drug advertising in medical journals

One hundred different drug advertisements from each of seven leading medical journals have been assessed. Information about drug interactions, adverse reactions, mode of action, absorption, distribution, metabolism, excretion and cost was seldom provided in UK journals. A requirement should exist that drug advertisements include such clinically important information. Only a few pharmaceutical companies are attempting to educate doctors through their marketing and promotional material in advertisements in medical journals.

Intracerebral haemorrhages and oral anticoagulation in the north of Scotland

The aim of this study has been twofold: 1--to examine the impact of oral anticoagulant (OAC) use on a possible recent rise in the admission rate of intracerebral haemorrhages to Aberdeen Royal Infirmary (ARI), and 2--to estimate the absolute risk of intracranial haemorrhage for outpatients followed up in the OAC Clinic at ARI. The number of patients admitted to ARI with intracerebral bleedings increased by 60% between 1993 and 1998. A corresponding increase in the proportion of patients with concurrent OAC use (4.7% vs 15.7%, p = 0.055) cannot sufficiently explain the increase in the total number of intracerebral haemorrhages. The average annual incidence of intracranial haemorrhages for the OAC Clinic at ARI is found to be acceptably low at 0.33% per year. Further audit of the large number of patients receiving warfarin outwith the supervision of the clinic is urgently required.

Accelerated hypertension--patterns of mortality and clinical factors affecting outcome in treated patients

We evaluated the outcome of patients presenting with accelerated hypertension, as part of an audit of the Aberdeen Hypertension Clinic database. Of 3928 patients (2005 male, 1923 female) referred for assessment of hypertension, 128 (77 male, 51 female) presented with accelerated hypertension. The main outcome measures were systolic and diastolic pressure, length of time from referral to death or censor date, and cause of death. Accelerated hypertensives had a higher death rate than other hypertensives. Using life-table analysis, age and serum creatinine at referral were sufficient to predict survival. Almost 50% (15/31) of the deceased accelerated hypertensives died of acute myocardial infarction. Mean survival after referral was estimated as 18 years for accelerated hypertensives (mean referral age 52 years) and 21 years for other hypertensives (mean referral age 48 years). Blood pressure fell most during the first year of treatment, and declined steadily thereafter. Systolic blood pressure fell by a mean of 50 mmHg and diastolic pressure by 30 mmHg in the first year, and at about 2 (diastolic) and 1 (systolic) mmHg/year for the next 10 years. Thus although the prognosis for accelerated hypertensives is not quite as good as for other hypertensives, with suitable care they can survive for a considerable period.

A comparison of amlodipine with enalapril in the treatment of moderate/severe hypertension

1. The safety and efficacy of amlodipine vs enalapril as monotherapy was evaluated in patients with moderate/severe hypertension (supine DBP 105-125 mm Hg, SBP 140-220 mm Hg). 2. After 2 weeks placebo treatment 31 patients were randomised by the technique of minimisation in an observer-blind study to receive once daily treatment with either amlodipine (15 patients) 5-10 mg, or enalapril (16 patients) 5-20 mg for 8 weeks. The study design concluded with 2 weeks placebo treatment. In addition to clinic measurements, home blood pressure monitoring (Copal UA-251) was performed during the study. 3. Clinic supine systolic blood pressure was reduced from 177 to 152 mm Hg (amlodipine) and 183 to 169 mm Hg (enalapril) (95% CI for the intergroup difference -22.1, 0.3, P = 0.06) after 8 weeks treatment. 4. Clinic supine diastolic blood pressure was reduced from 110 to 93 mm Hg (amlodipine) and 109-102 mm Hg (enalapril) (95% CI for the intergroup difference -17.7, -2.7, P < 0.01) after 8 weeks treatment. 5. Home blood pressure recordings confirmed these reductions in blood pressure. Although the reduction in blood pressure was greater for the amlodipine treated group, the differences between treatments were not statistically significant. 6. Both drugs were reasonably well tolerated. The adverse events occurring most frequently in the amlodipine group were headache (5), peripheral oedema (3), upper respiratory infection (3) and anxiety (2). The adverse events occurring most frequently in the enalapril treated patients were headache (6), dizziness (3) and upper respiratory infection (2).

A comparison of amlodipine with enalapril in the treatment of isolated systolic hypertension

1. The safety and efficacy of amlodipine and enalapril were compared in patients with isolated systolic hypertension (supine DBP < 95 mm Hg and supine SBP 160-200 mm Hg). 2. After 2 weeks treatment with placebo 31 patients were randomised by the technique of minimisation in an observer-blind study to receive once daily treatment with either amlodipine (16 patients) or enalapril (15 patients) for 8 weeks. The study design concluded with 2 weeks placebo treatment. In addition to clinic measurements, home blood pressure monitoring (Copal UA-251) was performed during the study. 3. Mean supine systolic blood pressure was reduced from 185 to 164 mm Hg (amlodipine) and 183 to 159 mm Hg (enalapril) (95% CI for the difference between the drugs -10.5, 15.3) after 8 weeks treatment. 4. Mean supine diastolic blood pressure was reduced from 86 to 80 mm Hg (amlodipine) and 88 to 80 mm Hg (enalapril) (95% CI for the difference between the drugs -4.9, 7.6) after 8 weeks treatment. 5. Home blood pressure recordings confirmed these reductions in blood pressure, although there was no significant difference between treatments for the reductions in blood pressure. 6. Both drugs were reasonably well tolerated. The adverse events occurring most frequently in the amlodipine group were headache (2), peripheral oedema (5) and palpitations (2). The adverse events occurring most frequently in the enalapril group were headache (2), peripheral oedema (2), palpitations (2) and dizziness (3).

Nicardipine sustained release in hypertension

1. A novel formulation of nicardipine (25% standard, 75% sustained release--SR) was evaluated in mild hypertension in a double-blind, randomized, placebo-controlled comparison with standard nicardipine (STD), using clinic measurements (Hawksley) augmented by home recorded blood pressures (Copal UA 251). 2. At 2 h after dosing (peak effect) both STD nicardipine (30 mg three times daily) and SR nicardipine (60 mg twice daily) for 28 days produced a highly significant reduction in sitting and standing blood pressure. The mean sitting blood pressure was reduced by 20/16 mm Hg (STD) and by 25/18 mm Hg (SR) compared with placebo. 3. Predose (8-11 h after last dose of STD, 12-15 h after last dose of SR) the reductions in sitting blood pressure relative to placebo were 11/6 mm Hg (STD) and 14/7 mm Hg (SR). 4. Home recordings confirmed the hypotensive effect of both formulations. Both exhibited a distinct 'peak dose' effect between 1-3 h after dosing. The effect of the SR formulation was sustained throughout the 12 h dosing interval. 5. Of the 60 patients entering the study, one died of unexplained staphylococcal septicaema, two were withdrawn for non drug-related reasons and 14 (32%) were withdrawn because of adverse effects on active therapy (headaches, facial flushing, leg oedema, chest pain, dizziness). 6. In the 43 patients who completed the study adverse symptoms were reported more frequently while they were on the two active formulations of nicardipine compared with placebo. Most of these reactions were again of vasodilator origin.(ABSTRACT TRUNCATED AT 250 WORDS)

Bench and ambulatory field evaluation of the A & D TM-2420 automated sphygmomanometer

Adequate evaluation of automated sphygmomanometers, in terms of safety, accuracy, mechanical reliability, patient acceptability and ability to record ambulatory blood pressure is essential before these devices are used in clinical practice and in clinical trials. We have evaluated the accuracy and performance of the A & D TM-2420 automated sphygmomanometer, an auscultatory device designed for ambulatory blood pressure recording. Four devices were tested for accuracy by simultaneous comparison against two experienced observers using standard mercury column sphygmomanometers. Two of these devices developed faults that precluded complete evaluation. One of the remaining devices met and one failed to meet the somewhat liberal criteria for accuracy recommended by the American Association for the Advancement of Medical Instrumentation, the current standard for evaluation (mean difference of less than or equal to 5 mmHg and standard deviation of differences less than or equal to 8 mmHg). The mean differences (standard deviation of differences) between observers for simultaneous triplicate observations of systolic/diastolic pressure in 50 subjects, including 35 hypertensives, were 0.8 (3.0)/-0.6 (2.4) mmHg. In comparison, the differences between each device and each observer were: device 11, observer 1, -6.4 (5.4)/-6.3 (9.9); device 11, observer 2, -5.6 (4.7)/-7.0 (10.4); device 12, observer 1, -4.9 (5.2)/-4.0 (7.5); device 12, observer 2, -4.1 (4.9)/- -4.5 (7.7) mmHg. Ambulatory trials were carried out with a further 10 devices. Of these, seven developed faults requiring their return to the supplier. Numerous additional problems were encountered with microphones, cuffs, leads and connections, the processing unit, error algorithms and data-handling software. The device was not capable of making truly ambulatory recordings. We do not confirm the previously favourable, but limited, evaluation of this device. We stress the vital importance of subjecting a number of devices to benchtesting for accuracy, and the need to undertake extensive 'field' testing before any devices can be considered suitable for ambulatory recording. Exercise testing under laboratory conditions is not an adequate substitue for true ambulatory evaluation.

The measurement of blood pressure: sitting or supine, once or twice?

In 166 patients attending a hypertension review clinic, we compared supine and sitting blood pressure measurements and first and second measurements (1 min apart) in each position to determine whether any differences seen might have implications for the routine measurement of blood pressure in these patients, as a group or as individuals. Measurements were made with the Copal UA-251 semi-automated sphygmomanometer. In the group there was no significant difference between the first and the second diastolic measurements. The first systolic measurement was on average 3-4 mmHg higher than the second in both positions. Mean supine systolic pressures were 2-3 mmHg higher and diastolic pressures 2-3 mmHg lower than the corresponding sitting pressures. In individual subjects there were substantial disagreements between successive measurements in both positions and between positions. However, these differences would not have influenced blood pressure management in more than a few instances. We suggest that two measurements should routinely be taken, and the average recorded, particularly when the average exceeds 155/90 mmHg.

Evaluation of a long acting formulation of nicardipine in hypertension by clinic and home recorded blood pressures and Doppler aortovelography

1. A novel formulation of nicardipine (50% standard (short acting), 50% sustained release) was evaluated in mild hypertension in a double-blind, randomized, placebo-controlled study, using clinic measurements (Hawksley) augmented by home recorded blood pressures (Copal UA 251). 2. Nicardipine 60 mg twice daily for 28 days produced a highly significant reduction in sitting blood pressure compared with placebo both pre dose (mean difference 17/8 mm Hg) and 2 h post dose (mean difference 34/26 mm Hg). 3. Home recordings confirmed the hypotensive effect and also revealed a consistent 'peak' effect between 2-4 h after dosing (mean difference 32/22) mm Hg). 4. Doppler aortovelography at 2 h post-dose showed a significant increase in in stroke and minute distance (linear analogues of stroke volume and cardiac output respectively) compared with placebo. The increase in stroke distance was linearly related to change in plasma concentration of nicardipine. 5. Of the 14 patients enrolled in the study, nine experienced troublesome adverse effects on nicardipine (headaches, facial flushing, palpitations, ankle oedema) and two of these were unable to complete the study as a result. 6. This formulation of nicardipine, in the fixed dosage used in this study, is characterized by an effective antihypertensive action but also by an unacceptable adverse effect profile, presumably due to an excess of its 'short acting' component.

Computer-assisted shared care: the Aberdeen Blood Pressure Clinic

A computer-assisted shared-care follow-up system, the patient record system, was used to follow up more than 3300 patients referred for assessment of hypertension. The patients are being followed up in collaboration with more than 250 general practitioners either in the hospital or in general practice, according to the assessment at each visit. The follow-up incorporates measures to control blood pressure below arbitrary target levels. Clinically important information is shared between doctors and between doctors and patients in order to highlight patients at risk, poor control of blood pressure, drug-host and drug-drug interactions and adverse reactions and to optimize the process and outcome of care.

Once-daily amlodipine in the treatment of mild to moderate hypertension

The antihypertensive efficacy of once-daily amlodipine was studied in a group of 30 patients with mild to moderate hypertension in a double-blind, placebo-controlled, parallel-group study. The dose range of amlodipine was 2.5-10.0 mg daily adjusted every 2 weeks for a total treatment period of 8 weeks. Amlodipine produced a significant reduction in blood pressure compared with placebo, the mean difference between baseline and 8 weeks (corrected for placebo effect) being 16/12 mm Hg supine, 14/4 mm Hg standing. Blood pressure returned to baseline values during a terminal 4-week washout period with placebo. There were no significant effects on heart rate. Two patients experienced slight ankle edema while receiving amlodipine 10.0 mg daily but the active drug was otherwise well tolerated.

Once daily amlodipine in the treatment of mild to moderate hypertension

1. The antihypertensive efficacy of once-daily amlodipine was studied in a group of 30 patients with mild to moderate hypertension in a double-blind, placebo controlled parallel group study. The dose range of amlodipine was 2.5-10 mg daily titrated at 2 weekly intervals for a total treatment period of 8 weeks. 2. Amlodipine produced a significant reduction in blood pressure compared with placebo, the mean difference between baseline and 8 weeks (corrected for placebo effect) being 16/12 mm Hg supine, 14/4 mm Hg standing. 3. Blood pressure returned to baseline values during a terminal 4 week washout period on placebo. 4. There were no significant effects on heart rate. 5. Two patients experienced slight ankle oedema while receiving amlodipine 10 mg daily but the active drug was otherwise well tolerated. 6. Plasma concentration of amlodipine, sampled 24 h after the preceding dose, increased as the dose titration sequence was followed, averaging 2.5 ng ml-1 on 2.5 mg, 4.9 ng ml-1 on 5 mg and 10.5 ng ml-1 on 10 mg.

Computer assisted shared care in hypertension

A computer assisted shared care scheme for the long term management and follow up of hypertensive patients has been developed in the Grampian Region. The scheme aims at facilitating the exchange of clinically important information between doctors and at achieving target levels of blood pressure with treatment in patients at highest risk of cardiovascular events. The shared care scheme has been well received by the local practitioners. Two hundred and fifty seven patients (18%) of 1426 patients under current long term follow up are assigned to follow up in the hospital aspect of the scheme. At the most recent visit 32% of patients in the hospital aspect and 10% of 1169 patients in the general practice aspect had blood pressure recordings above the target levels of 160/95 mm Hg. The stratification of patients formerly attending hospital clinics into grades of risk has rationalised our follow up procedures to allow the specialist resources to be freed and concentrated on those patients at highest risk and with the most complex problems. This computer assisted patient records system could be applied to other groups of high risk patients in whom long term follow up and surveillance are necessary--for example, patients with diabetes mellitus--and has implications for optimising and monitoring the delivery and outcome of care without overwhelming limited hospital resources.

Withdrawal of long-term therapy with atenolol in hypertensive patients

1 The offset of effects on blood pressure and heart rate after cessation of long-term therapy (19 +/- 3.6 months) with atenolol (200 mg once/daily) was studied in six hypertensive patients. 2 Withdrawal of atenolol resulted in a gradual return of lying, standing and post-exercise systolic and diastolic blood pressure levels and heart rate towards the baseline value. The offset of effect greatly exceeded the time for elimination of atenolol. 3 No significant differences in the pharmacokinetic profile of atenolol were evident between the values obtained following chronic dosing and an acute single-dose study. 4 The lack of clinical evidence of increased cardiac adrenergic sensitivity or rebound hypertension following withdrawal of atenolol contrasts with reports of a withdrawal syndrome following cessation of therapy with propranolol. Nevertheless until the mechanism of the propranolol-withdrawal syndrome is better understood caution is required when stopped therapy with atenolol in patients with severe coronary artery disease.

Cimetidine-a clinical and pharmacokinetic study

1 The effect of six months therapy with cimetidine (800 mg or 1600 mg/day) and subsequent withdrawal was studied in 19 patients with duodenal ulceration. 2 The overall rates of healing were 63% and 79% of patients after 3 and after 6 months of treatment respectively. The longer course (6 months) or the higher dose (1600 mg) did not result in significantly increased rates of ulcer healing. 3 Abrupt withdrawal of cimetidine resulted in the recurrence of severe symptoms in 15 patients (79%). 4 Pharmacokinetic studies showed the mean elimination half-life of cimetidine to be 100 +/- 25 min, the total body cimetidine clearance 652 +/- 223 ml/min, the mean volume of distribution at steady state 65 +/- 181 and the overall bioavailability 78%. 5 Long term cimetidine treatment does not result in drug accumulation or changes in its pharmacokinetic profile. 6 Inter-individual differences in clinical and endoscopic response to cimetidine cannot be explained by pharmacokinetic differences.

Atenolol, sustained-release oxprenolol, and long-acting propranolol in hypertension

The effect of once-daily atenolol, sustained-release oxprenolol (a new formulation of oxprenolol presented as a compressed tablet in a waxed matrix), and long-acting propranolol (a new formulation presented as spheriods in a capsule) was studied in a double-blind crossover trial in 23 carefully selected hypertensive outpatients. After a run-in period with matching placebo each patient received atenolol (100 mg/day), sustained-release oxprenolol (160 mg/day), long-acting propranolol (160 mg/day), and placebo according to a randomised sequence. After four weeks' treatment with sustained-release oxprenolol blood pressure in the two to four hours before the next dose was not significantly lower than after placebo. The effectiveness of atenolol and of the new formulation of propranolol in reducing blood pressure was confirmed. These results suggest that the present formulation of sustained-release oxprenolol should be reconsidered.

Prevention of adverse drug interactions

1 The awareness and recognition of adverse interactions between drugs by prescribers is low. 2 A 6-month prospective study on patients on long-term outpatient anticoagulant therapy in the Grampian area has been carried out to evaluate a simple and cheap warning system. 3 The practitioners of patients in the test group were issued with warning labels which showed drugs known to interact. A reduction in the initiation of prescriptions for potentially interacting drugs was shown between the test and control groups (no warning labels). 4 The 140 practitioners who completed the study found the system to be convenient and useful. Extension to other high-risk drugs with the potential to interact with other drugs is planned. This system has the advantage of being drug and patient-orientated whereas lists of drug interactions or drug discs require more conscious effort by the prescriber.

Atenolol once-daily in hypertension

1 The effect of atenolol, a cardioselective beta adrenoceptor antagonist, was studied in a double-blind crossover trial in twenty-one carefully selected hypertensive outpatients. Each patient received atenolol (50 mg/day, 100 mg/day, 200 mg/day) and placebo according to a randomized sequence in a once-daily dose. Wash-out periods on a matching placebo were included between the treatment periods. 2 The effect of lying, standing and post-exercise blood pressure of atenolol 50 mg once-daily was not significantly different from atenolol 100 or 200 mg once-daily. The reduction in lying and standing blood pressure was approximately 23/16 and 22/18 mm Hg from levels at the end of a run-in period on matching placebo of 167/108 and 162/112 mm Hg respectively. 3 The study shows that atenolol is an effective hypotensive agent in a once-daily dose.

Atenolol, methyldopa, and chlorthalidone in moderate hypertension

Combined treatment with low doses of different drugs is widely used for moderate hypertension. The effects of atenolol and methyldopa at two dose levels and in combination at the lower doses were studied in patients with moderate hypertension on continuous treatment with moderate hypertension on continuous treatment with chlorthalidone. The mean reduction in standing blood pressures obtained with atenolol 150 and 300 mg/day was about 27/17 mm Hg and with methyldopa 750 and 1500 mg/day about 28/14 mm Hg. Combined treatment with atenolol 150 mg/day and methyldopa 750 mg/day for four weeks resulted in a reduction of 38/25 mm Hg. No difference was observed between the two doses of methyldopa. The lower dose of atenolol was better than the lower dose of methyldopa in reducing lying and standing diastolic blood pressures. These findings show that in patients on continuous treatment with chlorthalidone the addition of atenolol alone or methyldopa alone or of atenolol and methyldopa in combination is effective in the treatment of moderate hypertension.

Methyldopa and propranolol or practolol in moderate hypertension

The effect of a low dose of methyldopa combined with (a) a non-selective and (b) a selective beta-adrenoceptor antagonist was studied in a double-blind crossover trial in 24 carefully selected patients with moderate hypertension (mean initial lying blood pressure 189/117 mm Hg). Each patient received methyldopa 750 mg/day, propranolol 240 mg/day, practolol 600 mg/day, methyldopa 750 mg/day combined with propranolol 240 mg/day, methyldopa 750 mg/day combined with practolol 600 mg/day, and placebo for four weeks each according to a random sequence. After four weeks of therapy the most effective treatment, methyldopa combined with propranolol, reduced lying and standing blood pressures by 36-5/21-4 mm Hg and 44-7/25 mm Hg respectively. Thic combination had similar effects to those of the combination of methyldopa with the cardioselective agent practolol except that it reduced lying diastolic pressure further. The combination was more effective than either treatment alone. No significant differences were found between the effects of propranolol, practolol, or methyldopa at the doses used.