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Mira Harrison-Woolrych

Publications and source records attributed to Mira Harrison-Woolrych.

12 recordsLinked to original sources
PubMed2006

QT interval prolongation associated with sibutramine treatment.

AIMS: To investigate a possible association of sibutramine with QT interval prolongation. METHODS: Post-marketing surveillance using prescription event monitoring in the New Zealand Intensive Medicines Monitoring Programme (IMMP) identified a case of QT prolongation and associated cardiac arrest in a patient taking sibutramine for 25 days. This patient was further investigated, including genotyping for long QT syndrome. Other IMMP case reports suggesting arrhythmias associated with sibutramine were assessed and further reports were obtained from the World Health Organisation (WHO) adverse drug reactions database. RESULTS: The index case displayed a novel mutation in a cardiac potassium channel subunit gene, KCNQ1, which is likely to prolong cardiac membrane depolarization and increase susceptibility to long QT intervals. Assessment of further IMMP reports identified five additional patients who experienced palpitations associated with syncope or presyncopal symptoms, one of whom had a QT(c) at the upper limit of normal. Assessment of reports from the WHO database identified three reports of QT prolongation and one fatal case of torsade de pointes in a patient also taking cisapride. CONCLUSIONS: This case series suggests that sibutramine may be associated with QT prolongation and related dysrhythmias. Further studies are required, but in the meantime we would recommend that sibutramine should be avoided in patients with long QT syndrome and in patients taking other medicines that may prolong the QT interval.

Adult↗
PubMed2005

Unintended pregnancies with the etonogestrel implant (Implanon): a case series from postmarketing experience in Australia.

This paper describes a case series of over 200 unintended pregnancies associated with the etonogestrel implant, Implanon. These cases have been reported to the Australian Adverse Drug Reactions Advisory Committee during the first 3 years of marketing in this country. Of 218 cases included, 45 had insufficient data to assess the reason for contraceptive failure and 46 women were determined to have been already pregnant prior to Implanon insertion. Of the remaining 127 cases, the most common reason for unintended pregnancy was failure to insert the implant in 84 women. Other reasons included incorrect timing of insertion (19 cases), expulsion of Implanon (3 cases) and interaction with hepatic enzyme-inducing medicines (8 cases). The remaining 13 cases were classified as product/method failures once other reasons had been excluded. Using the 204,486 Implanon devices subsidized in this period to estimate the population exposed and the 218 pregnancies reported, the approximate failure rate in postmarketing use was 1 in 1000 insertions. These findings (and reports to medical indemnity insurers) have resulted in the development of guidelines and training for doctors inserting Implanon in Australia.

Australia↗
PubMed2005

Incidence of thrombotic cardiovascular events in patients taking celecoxib compared with those taking rofecoxib: interim results from the New Zealand Intensive Medicines Monitoring Programme.

BACKGROUND: Rofecoxib was withdrawn from the market worldwide because of concerns relating to cardiovascular safety. There is conflicting evidence as to whether celecoxib, the most popular alternative to rofecoxib, carries the same cardiovascular risks. This study's aim was to compare the incidence of thrombotic cardiovascular events in patients taking celecoxib with patients taking rofecoxib. METHODS: Prescription event monitoring methodology was used in this prospective, longitudinal, observational cohort study, in which cohorts of patients were established from prescription data and thrombotic cardiovascular events were identified from follow-up questionnaires to patients' doctors and other sources. SUBJECTS: New Zealand patients with at least one prescription for either rofecoxib or celecoxib between 1 December 2000 and 30 November 2001. ANALYSIS: For this interim analysis the total cohorts were separated into three groups at different stages of follow-up: complete, incomplete and no follow-up. Cox's proportional hazards models were applied to calculate hazard ratios for celecoxib compared with rofecoxib. RESULTS: The total cohorts included 26,403 patients receiving rofecoxib and 32,446 patients receiving celecoxib. 4882 (18%) rofecoxib and 6267 (19%) celecoxib patients had been completely followed up. In this group the unadjusted hazard ratio for celecoxib compared with rofecoxib was 1.07 (95% CI 0.59, 1.93). After adjustment for age this hazard ratio was 0.94 (95% CI 0.51, 1.70). Further adjustment for sex, 'as required' use, indication for use, concomitant NSAID use and pre-existing cardiovascular disease resulted in only minor changes to the hazard ratio. CONCLUSION: This interim analysis of the Intensive Medicines Monitoring Programme data suggests that in 'real-life' postmarketing use in New Zealand there is no significant difference in the risk of cardiovascular thrombotic events in patients taking celecoxib compared with those taking rofecoxib.

Aged↗
PubMed2003

Insertion of intrauterine devices: a comparison of experience with Mirena and Multiload Cu 375 during post-marketing monitoring in New Zealand.

AIM: To compare the incidence of reported insertion problems with the levonorgestrel-releasing intrauterine device (Mirena) with that of the copper device Multiload Cu 375. METHODS: Prescription Event Monitoring (PEM) methodology, as used in the Intensive Medicines Monitoring Programme, was used to identify cohorts of women and record events associated with insertion. RESULTS: Data were analysed from 16 159 women receiving Multiload Cu 375 between 1991 and 2001, and 3452 women receiving Mirena between 1998 and 2001. Difficult insertion was reported more often with Mirena (RR= 2.7, 95% CI = 2.2--3.3, p <0.0001). Stratified analyses suggested this was not explained by the presence of more nulliparous women in the Mirena cohort or the non-contraceptive indications for use of Mirena. Mechanical problems with the device were reported in about 1% of Mirena insertions compared with 0.01% of Multiload Cu 375 insertions and this difference was significant (p <0.001). About 2% of Mirena insertions were performed under general anaesthetic compared with 0.1% of Multiload Cu 375 insertions. Adverse reactions to insertion, including pain and vaso-vagal reaction, were more frequent with Mirena than with Multiload Cu 375 (p <0.001). CONCLUSIONS: During the period of study, insertion of Mirena was more difficult and was associated with more device problems and adverse reactions than insertion of Multiload Cu 375.

Adolescent↗
PubMed2003

Uterine perforation on intrauterine device insertion: is the incidence higher than previously reported?

The objective of the study was to determine the rate of uterine perforation associated with insertion of Multiload Cu375 in 'real-life' clinical use. It was a prospective observational cohort study using Prescription Event Monitoring methodology. There were 17,469 Multiload Cu375 insertions in 16,159 women between 1991 and 2001. The insertions were performed by 1,699 different doctors (mostly general practitioners) in surgeries, clinics, and hospitals throughout New Zealand. The results found 28 reports suggesting complete or partial uterine perforation, giving an incidence of 1.6 per 1000 insertions. Most perforations (86%) were not diagnosed at the time of insertion, with some remaining undiagnosed for several years. Doctors who reported inserting fewer than 10 Multiload Cu375 devices in the study period reported significantly more perforations than doctors who reported inserting between 10 and 100 devices did. In conclusion, we found the perforation rate in this study is higher than in clinical trials of Multiload Cu375. This might be because of inclusion of partial perforations in this study, a longer follow-up period, the large number of insertions studied, or because the majority of inserting doctors were less experienced than inserters in other studies.

Adolescent↗
PubMed2002

Insertion of the Multiload Cu375 intrauterine device; experience in over 16,000 New Zealand women.

Insertion of Multiload Cu375 was studied in 16,159 women in a 10-year prospective observational cohort study in New Zealand. Of 17,468 insertions, about 9% were performed in nulliparous women. Problems fitting Multiload Cu375 (e.g., failed or difficult insertion) were experienced during approximately 2% of all insertions. The incidence of these was significantly higher in nulliparous women compared to parous women. Adverse reactions to insertion (e.g., pain, bleeding) occurred in 1.2% of all insertions, with nulliparous women experiencing significantly more adverse reactions than parous women. The insertions were performed by 1,700 different doctors in New Zealand with general practitioners performing 92% of these. Doctors who reported inserting over 100 devices in the study period experienced significantly less insertion problems than doctors who reported inserting less than 10 devices. This study suggests that insertion of Multiload Cu375 in a mixed community setting is associated with few inserting problems and adverse reactions to insertion. Risk factors identified for inserting problems included nulliparity and experience of the doctor inserting the intrauterine device.

Adolescent↗
PubMedDate not supplied

Use of the New Zealand Intensive Medicines Monitoring Programme to study the levonorgestrel-releasing intrauterine device (Mirena).

PURPOSE: To demonstrate how the Intensive Medicines Monitoring Programme (IMMP) can be used to monitor adverse events associated with an intrauterine device, using the levonorgestrel-releasing intrauterine device (Mirena) as an example. METHODS: A long-term prospective observational cohort study using Prescription Event Monitoring (PEM) is currently being undertaken in women using Mirena in New Zealand. This report describes the method used and reports the early results for those women who used the device between March 1998 and March 2001. Adverse events were recorded by inserting doctors and general practitioners on registration forms and systematic follow-up questionnaires. RESULTS: Between March 1998 and March 2001, the IMMP received 3519 registration forms for insertions in 3452 women. 'Difficult insertion' was the most frequently reported event (3.6% of all insertions). Approximately, 2% of the Mirena insertions were carried out under GA and there were three uterine perforations (0.9 per 1000 insertions) in the total cohort. To date, follow-up questionnaires have been processed for 495 patients. The response rate for these was 83%. CONCLUSION: As adapted in the IMMP, PEM is an effective tool for the early post-marketing surveillance of an intrauterine device in real life clinical practice.

Adolescent↗