Troglitazone (Rezulin) and hepatic injury.

PURPOSE: Analyze US rates of reported severe liver disease for the oral hypoglycemic agent troglitazone from March 1997 through February 2000 and the possible effects of publicity on reporting. METHODS: The number of troglitazone reports with liver failure and or hospitalization with jaundice or hyperbilirubinemia, made to the FDA and/or Parke-Davis are used as numerators. The denominators are numbers of patients and person-time estimates of exposure. Additionally, the amount of publicity about troglitazone during its marketing is quantified. RESULTS: Approximately 1.92 million patients were treated with troglitazone from March 1997 through the end of February 2000 resulting in 1.6 million person-years of exposure. Reports of 83 cases of liver failure associated with troglitazone were received (1 in 23,000 patients or 1 in 20,000 person-years). Of the 83 cases, only 49 (59%) were classified by a hepatologist to be 'possibly' or 'probably' attributed to troglitazone. For the first, second, and third years of marketing, rates of reported hepatic failure per 100,000 person years exposure to troglitazone were 8.3, 5.3, and 2.7 respectively. Rates of reported liver disease involving hospitalizations with mention of jaundice and hyperbilirubinemia per 100,000 person-years were 16.0, 6.1, and 3.6 respectively for these years. During the 3-year marketing history of troglitazone, there were 470 lay press and 158 medical literature articles with mentions of hepatotoxicity for the drug. CONCLUSIONS: Rates of reported severe liver disease declined substantially during the second and third years of marketing of troglitazone. The decline followed increasingly stringent requirements for liver function test monitoring and may have been due to improved patient selection and management as a result of the widely publicized association between troglitazone and hepatotoxicity.

Effect of onychomycosis on quality of life.

BACKGROUND: Onychomycosis impairs normal nail functions, causes considerable pain, interferes with daily activities, and has negative psychosocial effects. OBJECTIVE: Our purpose was to determine patients' perception of onychomycosis on the quality of life. METHODS: A total of 258 patients with confirmed onychomycosis were surveyed by telephone at three centers. Responses to a standardized quality-of-life questionnaire were analyzed for patient demographics, physical and functional impact, psychosocial impact, and economic impact. RESULTS: Highest positive responses were nail-trimming problems (76%), embarrassment (74%), pain (48%), nail pressure (40%), and discomfort wearing shoes (38%). Ability to pick up small objects was impaired in 41% of subjects with fingernail involvement. More than 58 onychomycosis-related sick days and 468 medical visits (1.8 per subject) were reported during a 6-month period. CONCLUSION: Onychomycosis has significant social, psychologic, health, and occupational effects. Relevance of quality-of-life issues to overall health, earning potential, and social functioning should prompt reconsideration of the value of aggressive treatment of and financial coverage for onychomycosis.

US adverse drug reaction surveillance 1989-1994.

Adverse drug reaction surveillance conducted by the US Federal Food and Drug Administration (FDA) is important for detecting new safety information about pharmaceuticals. FDA has sought to stimulate reporting of reactions by practitioners and manufacturers. Over the five years from 1989 to 1993, reporting more than doubled and a total of 421,491 reports were received. This trend continued in 1994. The origin, type of reaction and drug are presented. Most reports are made by health professionals through pharmaceutical manufacturers. About 5% of such reports involve serious reactions to new drugs. Uses and limitations of ADR surveillance are briefly discussed.

Terfenadine-associated ventricular arrhythmias and QTc interval prolongation. A retrospective cohort comparison with other antihistamines among members of a health maintenance organization.

This study compared the occurrence of syncope, ventricular arrhythmias, and corrected QT interval (QTc) prolongation over a 2 1/2-year period in persons prescribed terfenadine versus other prescription antihistamines among 265,000 members of the Harvard Community Health Plan (HCHP), the largest staff-model health maintenance organization in New England. HCHP maintains an automated medical record system with coded diagnoses for each ambulatory and hospital visit, and a similar automated pharmacy system with information for each member on all prescriptions filled at its pharmacies. Among 0.86 million exposure days of terfenadine and 1.04 million exposure days of other antihistamines, we found no excess risk of either clinical/arrhythmia events (odds ratio (OR), 0.86; 95% confidence interval (CI), 0.52 to 1.44) or QTc prolongation (OR, 1.00; 95% CI, 0.64 to 1.57) during courses of terfenadine versus those of other antihistamines. Joint courses of antihistamines and oral erythromycin were associated with an increased risk of QTc prolongation (OR, 2.33; 95% CI, 1.31 to 4.15), and there was a trend for this to be observed more frequently with terfenadine (OR, 2.37; 95% CI, 0.73 to 7.51; P = 0.14).

Effects of exposure to benzodiazepine during fetal life.

Dysmorphism and mental retardation have been reported in 7 Swedish children born of mothers who had taken high doses of benzodiazepines regularly during pregnancy. To explore this association further, we examined benzodiazepine use during pregnancy in 104,000 women whose deliveries were registered by the US public health insurance system, Medicaid, during 1980-83. Fetal outcomes were assessed from the health claims profiles of their offspring, up to 6-9 years after delivery. 80 pregnant women had received 10 or more benzodiazepine prescriptions during the 4 years. Their records showed heavy general use of health care and frequent alcohol and substance abuse, and other disorders that could confound any effect of the benzodiazepines. For the 80 pregnancies, 3 intrauterine deaths were identified as well as 2 infants with congenital abnormalities whose curtailed records suggested neonatal death. Records of 64 surviving children could be linked to these 80 pregnancies whilst records for 11 apparent survivors could not be located. 6 of the 64 survivors had diagnoses consistent with teratogenic abnormalities. The high rate of teratogenicity after heavy maternal benzodiazepine use occurs with multiple alcohol and substance exposure and thus may not be due to benzodiazepine exposure.

Clustering of adverse drug events: analysis of risk factors for cerebellar toxicity with high-dose cytarabine.

BACKGROUND: Cerebellar toxicity is a severe, therapy-limiting adverse reaction of cytarabine given in high doses. The Food and Drug Administration received a report of an increased frequency of cerebellar toxicity at the University of Wisconsin Hospital and Clinics after a switch from the product (Cytosar-U) manufactured by The Upjohn Co., Kalamazoo, Mich., to the generic form made by Quad Pharmaceuticals, Inc., Indianapolis, Ind. PURPOSE: To compare the incidence of cerebellar toxicity in Quad-treated patients with Upjohn-treated patients, a record-based cohort study was conducted at the University of Wisconsin Hospital and Clinics between January 1986 and August 1989. METHODS: The incidence of cerebellar toxicity was studied in 63 leukemia patients according to the manufacturer of the product received (34 Upjohn only, 25 Quad only, and four both manufacturers). The relative risk of cerebellar toxicity was adjusted for other known risk factors. RESULTS: Patients in the manufacturer-defined treatment groups did not differ significantly with respect to age, sex, type of leukemia, disease stage, calculated creatinine clearance, presence of abnormal liver function tests, or total dose received. The crude relative risk of cerebellar toxicity comparing the Quad product with the Upjohn product was 5.0 (95% confidence interval = 1.8-13.7). Adjustment for potential confounders did not alter the association. Other risk factors for cerebellar toxicity, independent of manufacturer, were age greater than 50 years, type of leukemia, disease stage, total dose greater than or equal to 20 g/m2, abnormal pretreatment liver function, and reduced creatinine clearance. CONCLUSION: This study found a significantly higher incidence of cerebellar toxicity with high-dose cytarabine manufactured by Quad Pharmaceuticals when compared with the incidence of cerebellar toxicity with the Upjohn product. Further research at independent institutions would be necessary to allow generalization of this finding. In addition, our findings suggest that a dose reduction in high-dose cytarabine therapy may be indicated for patients with reduced glomerular filtration rates.

National adverse drug reaction reporting. 1984-1989.

Surveillance of adverse reactions due to pharmaceuticals is important because the drug approval process cannot totally assure safety and because new knowledge is bound to accrue after drugs enter usual medical practice. Reporting of reactions to the Food and Drug Administration increased markedly between 1985 and 1989 and totaled 261,515 reports for this period. A large part of this increase was due to new legal requirements, which ensure that manufacturers report reactions to the Food and Drug Administration. Most reaction reports originated with practicing physicians who contacted drug manufacturers. High proportions of the reports involved new drugs and serious reactions. Reaction surveillance leads to 50 to 100 important safety investigations annually and to numerous changes in product information. Health care providers must continue to report suspect adverse reactions to the Food and Drug Administration and manufacturers if pharmaceutical use and safety are to improve.

International reporting on adverse drug reactions: the CIOMS project. CIOMS ADR Working Group.

A method for standardized postapproval adverse drug reaction (ADR) reporting has been developed and implemented by seven multinational pharmaceutical manufacturers and six regulatory authorities. This is based on a set of uniform definitions, procedures and a single reporting form, and has been demonstrated to be useful and effective. When regulators and manufacturers develop requirements and systems for ADR reporting they should consider adapting this method.

Physician reporting of adverse drug reactions. Results of the Rhode Island Adverse Drug Reaction Reporting Project.

The Food and Drug Administration, Rockville, Md, contracted with the Rhode Island Department of Health, Providence, to conduct a project to increase reporting of suspected adverse drug reactions through physician education. Voluntary reporting, an important part of postmarketing surveillance that signals potential problems with marketed drugs, historically has been underused by physicians. After 2 years, there was a more than 17-fold increase in reports submitted directly from Rhode Island compared with the yearly average before initiation of the project. Increases in the total numbers of reports were paralleled by significant increases in the numbers of reports of severe reactions. Similar increases were not experienced nationally. Physicians in Rhode Island were surveyed before and 2 years after interventions began to determine changes in knowledge and attitudes about reporting of adverse drug reactions. Significant gains in knowledge and positive attitudes toward the reporting system occurred. We conclude that physicians can be stimulated to increase their reporting of suspected reactions, thereby improving the viability of the federal reporting system.

A method of pharmacoepidemiologic analysis that uses computerized Medicaid.

A method of pharmacoepidemiologic data analysis that utilizes computerized Medicaid data is presented. A cohort design in which Medicaid enrollees receiving drugs that are normally used to treat similar underlying conditions is described. A period of time in which Medicaid service transactions are evident is required before an individual is eligible for selection into a cohort. Selection of study subjects and descriptions of cohorts are based on Medicaid service histories occurring during the preliminary, prerequisite period. Time at risk is considered to begin after a prescription for a study drug is dispensed and continues until either a refill is dispensed, a prescription for an alternative drug within the same therapeutic class is dispensed, or a predetermined number of days has passed. Subjects are followed forward in time and relevant health care transactions that are suggestive of suspected adverse drug reactions are noted. Incidence densities associated with sequentially ranked prescriptions within sequential courses of therapy are compared. Methods to increase the accuracy of case ascertainment are briefly discussed. Separate validation studies may be used to evaluate the validity of computerized case ascertainment methods and to compensate for misclassification of outcome. The proposed method is intended to provide timely estimates of risk for selected outcomes. For outcomes that cannot be accurately ascertained from computerized data, this method may be useful in determining the feasibility of more customized studies.