[Retrospective of national pharmacovigilance surveys on drug-induced bullous, vesicular eruptions: methods and results ]

The academic interest for pharmacovigilance appears to be very low, because of the judged weakness of a "significant" relationship between drug utilisation and pathological events. We have tried to collect the relevant surveys of the French pharmacovigilance network on cutaneous toxic reactions to show the use of this work for current medical knowledge. This study was limited to the most relevant reports: 1--Cutaneous disorders induced by local reactions to ketoprofen, bufexamac, paracetamol (i.v.) 2--Cutaneous disorders observed in systemic hypersensitivity syndromes: allopurinol, chlormezanone, pristinamycine 3--Photosensitisation (toxicity), including: Individual characteristics of patients Nature of the observed syndromes Induction time and evolution of the disease Imputation and apparent incidence of the cases observed

RESULTS

1--Concerning "contact" dermitis, erythematous skin reactions are the most frequently observed. The causality link is proved in 272 patients of the cases. The mean age of the patients is 40-50 and the induction time from one to ten days. 2--In the hypersensitisation syndromes, severe skin reactions, combined with general reactions (fever), are the most frequently observed. The mean age is 50-60 and the number of serious cases is high (4.5%). 3--Severe burns with bullous skin reactions are observed in phototoxicity cases. The mean age of the patients is 50. Time induction is short (ten days), the cases are frequently serious, but evolution appears good. In conclusion, the synthesis of pharmacovigilance surveys shows the value of this epidemiological approach to drug-induced skin reactions. It is regrettable that the results of this work are not more widely distributed.

Reports of hypoglycaemia associated with the use of ACE inhibitors and other drugs: a case/non-case study in the French pharmacovigilance system database

AIMS

To test the existence of an association between reports of hypoglycaemia and angiotensin converting enzyme inhibitors, in a spontaneous reports database.

METHODS

The French Pharmacovigilance database was examined for an association between adverse drug reaction reports mentioning hypoglycaemia, and angiotensin converting enzyme inhibitors (ACEI) using the case/non-case methodology, with reports of hypoglycaemia as cases and all other reports as comparators. The association between ACEI or other chosen drugs and hypoglycaemia was also tested in the subgroups of patients taking or not antidiabetic agents (ADA).

RESULTS

428 of 93,338 reports mentioned hypoglycaemia (202/2227 with ADA (OR 40, 95% CI 33-48)). 46/5717 reports mentioned ACEI (OR 1.8 (1.25-2.54)). Other study drugs associated with hypoglycaemia were cibenzoline (OR 80 (57-112)), disopyramide (OR 32 (22-46)), nifedipine (OR 2.16 (1.32-3.51)), diltiazem (OR 1.76 (1.01-3.06)) nitrates (nitroglycerin, molsidomine) (OR 1.91 (1.16-3.16)) and frusemide (OR 1.89 (1.31-1.76)), but not nicardipine, amlodipine, felodipine or nitrendipine, diazepam, atenolol or combination thiazide diuretics. However, ACEI and other drugs were associated with ADA, so that in the subgroups of patients taking or not ADA, the association of ACEI with hypoglycaemia disappeared (OR 0.9 (0.5-1.4) and 1.2 (0.7-2.2), respectively). The same was found for other drugs except cibenzoline.

CONCLUSION

The association between reporting of hypoglycaemia and ACE inhibitors was related to concomitant use of antidiabetic agents. This was true also for other drugs used in arterial disease or renal failure, such as calcium channel blockers, nitrates, and frusemide.

[French pharmacovigilance database system: examples of utilisation]

The French drug surveillance (pharmacovigilance) system is based on a network of 31 regional centres which receive adverse drug reaction (ADR) reports from health professionals and are drug information centers. Cases are entered into a common database, with causality scores. This database contains large amounts of data, which may be used for pharmaco-epidemiological studies. As an example, all cases in which an antihypertensive drug, suspect or not, was cited were identified. ACE-inhibitor cough was also explored.

RESULTS

Since 1985, > 70,000 case reports have been entered into the database. 63 per cent were reported by specialists, 20 per cent by GPs. 54 per cent came from University Hospitals, 21 per cent from private practice. The most numerous age group was 60 to 69. The overall sex ratio (F/M) was 1.28, the female preponderance being most marked at < 39 and > 70 years of age. 43 per cent took only one drug, 20 per cent two drugs, 13.4 per cent three, and 24 per cent > three drugs. The most frequently reported effects concerned the skin and appendages (15 per cent), general status and central nervous system (9.5 per cent each), platelets, liver, and GI systems (6 per cent each). Outcome was favourable in 74 per cent. Dechallenge was positive in 71 per cent, rechallence in 6 per cent. 3.4 per cent of the patients died; in 2.2 per cent death was related to a reaction. Causality assessment indicated close temporal relationship (C2 or C3) in 69 per cent of cases; in 51 per cent of cases, no other obvious cause was found. 66 per cent of the reactions were labelled when reported. The database could also be used to explore drug utilisation: as an example, we studied the age and sex distribution of reports containing antihypertensive drugs, irrespective of their possible causal role in the reaction. Antihypertensives were mentioned in 14 per cent of the reports. The age distribution was skewed towards greater age, with a maximum of 70 years. F/M was 1.57, with more M use < 20 and 30-59, whereas F were more common between 20-29 and 60 years. beta-blockers were more often associated with patients under 70, whereas above 70 diuretics and centrally acting antihypertensive drugs were more often reported. This could be related to greater use or worse tolerance of these drugs. As an example of the exploration of a specific drug-reaction relationship, we explored the relationship between the use of ACE inhibitors (ACEI) and cough. ACE inhibitors were present in 6 per cent of cases, but in 75 per cent of reports of cough. F/M was 1.29 (NS) for all reports concerning ACEI, 1.28 for cough unrelated to ACEI, 2.1 for cough with ACEI (P < 0.05). Cough was present in 12 per cent of all reports concerning ACEI. There was no clear difference between ACEI for cough or sex ratio; women cough more with ACEI. This does not seem related to greater ACEI use by women or to greater sensitivity of women to cough. The reason for this sex difference remains to be explained. There are large amounts of essentially underutilized data in drug surveillance databases. How they can or should be used remains to be validated.

[Calcium antagonists and arterial hypertension]

The pharmacological class of calcium channel antagonists (CCA) is, with beta-adrenergic antagonists, diuretics, converting enzyme inhibitors and alpha-adrenergic antagonists, one of the first line monotherapies of essential hypertension, according to the recommendations of the "Fifth Joint National Committee on Detection, Evaluation and Treatment of Hypertension". CCA have several advantages for the treatment of hypertension: the blood pressure lowering effect is due to a reduction of total peripheral vascular resistance, which are primarily abnormally increased in hypertension; the antihypertensive efficacy of CCA is comparable to that of other commonly used antihypertensive drugs; CCA induce a significant regression of left ventricular hypertrophy, a factor of morbidity and mortality which is considered to be independent of the level of mean arterial pressure; CCA have vasodilating properties on the coronary circulation; CCA are generally well tolerated, from both clinical and biological points of view. The challenge for CCA concerns three domains related to the morbidity/mortality of hypertension (coronary and cerebrovascular events) a better antihypertensive efficacy for the whole period of 24 hours, a better prevention of cerebrovascular events and an effect on the development of atherosclerosis.

Cyclosporine-induced stimulation of the renin-angiotensin system after liver and heart transplantation

To analyze the status of the renin-angiotensin system in hypertensive transplant recipients on cyclosporine, we prospectively explored 21 cardiac (CTR: 52 +/- 8.2 yr) and 12 liver (LTR: 45 +/- 10 yr) transplant recipients on a normal salt diet with 19 normotensive controls in the same age range. Systolic and diastolic blood pressure was measured in the supine and standing positions. Renal function was assessed by serum creatinine values, and 24-hr urinary sodium and potassium excretion were recorded. Plasma renin activity (PRA), active renin, total renin, angiotensinogen, aldosterone, and cortisol plasma levels were simultaneously determined. Results were expressed as mean +/- SD, and between-group differences were compared using variance analysis. Supine blood pressure (+/- SD) was 158 +/- 15/103 +/- 8.4 in CTR and 155 +/- 21.4/102 +/- 11.7 mmHg in LTR. Serum creatinine was higher in CTR (159 +/- 52 mumol/L) than in LTR (117 +/- 24.7, P < 0.05) and values in both groups were above controls (83 +/- 14.1, P < 0.05). Urinary sodium excretion tended to be lower in transplant recipients (59 +/- 42 mmol/L) for CTR and 44 +/- 36.7 in LTR than in healthy controls (117 +/- 24.7 mmol/L). Supine and upright PRA values tended to be higher in hypertensive transplant recipients than in healthy volunteers, although not significantly. Supine active renin was significantly higher in CTR (47 +/- 42 pg/ml) and in LTR (44 +/- 29.8 pg/ml) than in normal subjects (17 +/- 4.8 pg/ml, P < 0.05). Total renin levels in CTR (supine: 716 +/- 357 pg/ml) and in LTR (supine: 647 +/- 365 pg/ml) were 3- to 4-fold higher than in controls (supine: 207 +/- 69 pg/ml) (P < 0.05), as were inactive renin levels (P < 0.01). Active renin was effectively correlated with PRA (P < 0.001) and with total renin (P < 0.001) in the supine and in the upright position. Plasma aldosterone was almost within the normal range in CTR and in LTR, and it did not correlate with PRA values. Plasma angiotensinogen levels were normal in LTR (1032 +/- 226 ng/ml) but were significantly lower in CTR (938 +/- 216 ng/ml, P < 0.05). Cortisol plasma levels were lower in both CTR (7 +/- 4.4 micrograms/L) and LTR (6 +/- 1.9 micrograms/L) than in healthy controls (11 +/- 4 micrograms/L, P < 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)

[Do converting enzyme inhibitors differ from each other in the treatment of hypertension?]

Novel angiotensin converting enzyme inhibitors (ACE inhibitors) have recently been commercialized and the question arises whether differences in pharmacodynamic and pharmacokinetic properties should lead to specific therapeutic choices. To our knowledge there is no data which allows the physician to conclude to any different antihypertensive efficacy when ACE inhibitors are used at adequate dosage. Their pharmacokinetic characteristics may differ at every level: absorption, distribution, metabolism and excretion. Differences in chemical structure may also influence their diffusion in various tissues, therefrom the amplitude and duration of inhibition of angiotensin II at these sites. The duration of maximum blockade of ACE and the amplitude of residual blockade may theoretically influence the duration of the hypotensive effect and the number of daily dosages. Once-daily administered long acting ACE inhibitors keep their antihypertensive action through the whole 24-hour period, during chronic treatment. The theoretical advantage of such a property is an improved control of 24-hour blood pressure. However, no study, to our knowledge, concluded to any difference between long acting ACE inhibitors as far as this parameter was concerned. In addition, except captopril which has been reported to induce major untoward effects at the time high dosages were introduced, ACE inhibitors do not seem to bear different undesirable effects.

[Critical analysis of drug interactions with cyclosporine. Evaluation of interactions with cyclosporine]

Cyclosporine A is a potent immunosuppressive agent, widely used in organ transplantation, in bone marrow transplantation and in the treatment of some autoimmune diseases. Changes of its absorption, a metabolism mainly processed by the liver and a concentration-related nephrotoxicity lead to the need of a careful drug monitoring, allowing to obtain blood levels that must be low and nevertheless sufficiently efficient. Cyclosporin A may additionally yield some numerous drug interactions. Those with potentially serious issue must be mandatory avoided and distinguished from those less severe that only have to be followed up. The strategy differs according to the nature of the interaction (i.e. pharmacokinetic/pharmacodynamic): the posology will have either to be adjusted or the risk/benefit ratio will have to be taken into account to decide any change in the dosage regimen.

[Clinical evaluation of drug interactions of cyclosporin]

Cyclosporin is a nephrotoxic immunosuppressant metabolized in the liver and requiring drug monitoring. Numerous pharmacokinetic and pharmacodynamic drug interactions have occurred with this compound. Some of them are well substantiated while others are merely suspected. The major interactions must definitely be prevented of corrected, whereas the others need no more than careful drug monitoring.

Efficacy and tolerance of spironolactone in essential hypertension

The long-term efficacy and tolerance of spironolactone in essential hypertension was evaluated among 20,812 patients referred to the Broussais and St. Joseph systemic hypertension clinics between 1976 and 1985 by using information prospectively collected in the computerized ARTEMIS data bank. In 182 patients (51 men, 131 women) treated with spironolactone alone during a mean follow-up period of 23 months, a mean dose of 96.5 mg decreased systolic and diastolic blood pressure (BP) by 18 and 10 mm Hg, respectively, below pretherapeutic levels. The BP decrease was greater with doses of 75 to 100 mg (12.4% and 12.2%) than with doses of 25 to 50 mg (5.3 and 6.5%, p less than 0.001), but no additional decrease was found with doses above 150 mg. Plasma creatinine level increased modestly (8.3 mumol/liters), as did plasma potassium level (0.6 mmol/liters) (both p less than 0.001); uric acid level increased, but not significantly (10.5 mumol/liter). Fasting blood glucose and total cholesterol levels did not change, triglyceride levels increased slightly (0.1 mmol/liter, p less than 0.05). These changes were similar in both sexes and were not influenced by length of follow-up. Among the 699 men prescribed spironolactone alone or in association with another antihypertensive treatment, 91 cases of gynecomastia developed (13%). Gynecomastia was reversible and dose-related; at doses of 50 mg or less the incidence was 6.9%, but 52.2% for doses of 150 mg or higher. Despite limitations inherent in the interpretation of data banks, it is concluded that spironolactone administered in daily practice reduced BP without inducing adverse metabolic adverse effects and that in patients with essential hypertension, doses should be kept below 100 mg.