Alison Hitchcock

Monash Medical Centre, Clayton, Melbourne, Victoria, Australia

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Publications (11)14.15 Total impact

  • Source
    Article: Seizure control in antiepileptic drug-treated pregnancy.
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    ABSTRACT: This brief report covers an analysis of 7 years outcome data from the Australian Register of Antiepileptic Drugs in Pregnancy. In studying the control of antiepileptic drug-treated epileptic seizures during pregnancy, it was found that pregnancy had little influence on antiepileptic drug-treated epileptic seizure disorders. Seizures during pregnancy occurred in 49.7% of 841 antiepileptic drug (AED) treated pregnancies in women with epilepsy. Epilepsies that were active in the year before pregnancy tended to increase the risk of intrapartum and postpartum seizures. The risk of seizures during pregnancy was 50-70% less if the prepregnancy year was seizure free, and decreased relatively little more with longer periods of prepregnancy seizure control. Once there had been 1 year's freedom from seizures there seemed relatively little further advantage in deferring pregnancy to avoid seizures returning while pregnant.
    Epilepsia 02/2008; 49(1):172-6. · 3.96 Impact Factor
  • Article: The internal control group in a register of antiepileptic drug use in pregnancy.
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    ABSTRACT: The aim of this study was to determine how valid 68 first-trimester pregnancies of untreated epileptic women would prove as an internal control group for investigating foetal malformation rates in 709 simultaneously collected antiepileptic drug-exposed pregnancies in an Australian register of pregnancies in epileptic women. We carried out comparisons of values for parameters relating to personal details, obstetric aspects, and epilepsies prior to and during pregnancy in the drug-exposed and drug-unexposed pregnancies, with observations on subpopulations within the drug-unexposed group. Statistically significant (p<0.05) differences existed for only seven of more than 50 parameters compared. None of these seven parameters had a statistically significant influence on foetal malformation rates in the whole dataset. In 23 of the 65 epileptic pregnancies unexposed to antiepileptic drugs, therapy had been ceased shortly prior to pregnancy and was often resumed after the first trimester. In the remaining 42, therapy had been ceased earlier, often despite continuing seizures. Planned withdrawal of therapy did not appear to produce additional hazards for mothers and foetuses in the former subgroup. In the data collection studied, there did not appear to be evidence of statistically significant differences between untreated pregnancies and treated epileptic pregnancies that would be likely to invalidate the former group as an internal control for the latter, at least when assessing foetal malformation rates.
    Journal of Clinical Neuroscience 01/2008; 15(1):29-35. · 1.25 Impact Factor
  • Article: The Australian Register of Antiepileptic Drugs in Pregnancy: the first 1002 pregnancies.
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    ABSTRACT: Prospective studies are needed to assess the maternal and fetal hazards of antiepileptic drug (AED) therapy in pregnancy. To make the Australian Register of AEDs in Pregnancy better known to the Australian obstetric community by presenting results derived from it. Analysis of data collected by the Register between 1999 and December 2006. The Register contained data on 1002 epileptic or AED-treated pregnancies, 992 with known outcomes, 83 not exposed to AEDs in at least their first trimester, and 30 prescribed AEDs for indications other than epilepsy. Statistically significant findings included more frequent folate supplementation and decreased alcohol intake during pregnancy in women with epilepsy; a dose-related increased risk of fetal malformation associated with valproate therapy; a tendency towards lower birthweights in live-born malformed offspring; and a substantially reduced decreased risk of seizures in pregnancy with one year seizure freedom before pregnancy. The small numbers of patients may have prevented other differences from reaching a P<0.05 value. The Register has already produced important information for the management of pregnant women with epilepsy in Australia, but greater rates of recruitment into the Register are desirable to allow it to achieve its full potential.
    Australian and New Zealand Journal of Obstetrics and Gynaecology 12/2007; 47(6):468-74. · 1.24 Impact Factor
  • Article: The Australian antiepileptic drug in pregnancy register: aspects of data collection and analysis.
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    ABSTRACT: Internal comparisons using the data of the Australian Register of Antiepileptic Drugs in Pregnancy as of November 2005, and comparisons with Australian population data, were carried out. It was found that (i) except for under-representation of mothers of Asian origin, the demography of the register population was reasonably representative of the Australian situation; (ii) except for more pregnancies terminated for foetal malformation, malformation rates were similar in retrospectively and non-retrospectively enrolled pregnancies; (iii) some 21% of foetal malformations would have been excluded by not including malformations first recognised after the neonatal period; and (iv) in practice, the comparator against which malformation rates were expressed made little difference to the rates found. It is desirable to have available such analyses of pregnancy register data before comparing the findings of different registers.
    Journal of Clinical Neuroscience 11/2007; 14(10):936-42. · 1.25 Impact Factor
  • Article: Australian pregnancy registry of women taking antiepileptic drugs.
    Epilepsia 12/2004; 45(11):1466. · 3.96 Impact Factor
  • Article: Critical relationship between sodium valproate dose and human teratogenicity: results of the Australian register of anti-epileptic drugs in pregnancy.
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    ABSTRACT: To compare the incidence of foetal malformations (FMs) in pregnant women with epilepsy treated with different anti-epileptic drugs (AED) and doses, and the influence of seizures, family and personal history, and environmental factors. A prospective, observational, community-based cohort study. A voluntary, Australia-wide, telephone-interview-based register prospectively enrolling three groups of pregnant women: taking AEDs for epilepsy; with epilepsy not taking AEDs; taking AEDs for a non-epileptic indication. Four hundred and fifty eligible women were enrolled over 40 months. Three hundred and ninety six pregnancies had been completed, with 7 sets of twins, for a total of 403 pregnancy outcomes. 354 (87.8%) pregnancy outcomes resulted in a healthy live birth, 26 (6.5%) had a FM, 4 (1%) a death in utero, 1 (0.2%) a premature labour with stillbirth, 14 (3.5%) a spontaneous abortion and 4 lost to follow-up. The FM rate was greater in pregnancies exposed to sodium valproate (VPA) in the first trimester (16.0%) compared with those exposed to all other AEDs (16.0% vs. 2.4%, P < 0.01) or no AEDs (16.0% vs. 3.1%, [Formula: see text] ). The mean daily dose of VPA taken in pregnancy with FMs was significantly greater than in those without (1,975 vs. 1,128 mg, P < 0.01). The incidence of FM with VPA doses >or= 1,100 mg was 30.2% vs. 3.2% with doses <1,100 mg (P <0.01). There is a dose-effect relationship for FM and exposure to VPA during the first trimester of pregnancy, with higher doses of VPA associated with a significantly greater risk than with lower doses or with other AEDs. These results highlight the need to limit, where possible, the dose of VPA in pregnancy.
    Journal of Clinical Neuroscience 11/2004; 11(8):854-8. · 1.25 Impact Factor
  • Article: The Australian registry of anti-epileptic drugs in pregnancy: experience after 30 months.
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    ABSTRACT: Most women with epilepsy need to take antiepileptic drugs (AEDs) in pregnancy to prevent the potentially harmful effects of seizures. Retrospective studies have demonstrated an increased chance of having a child with a birth defect (BD) in women with epilepsy taking AEDs. It is uncertain how much of this risk is directly caused by the AEDs and whether certain drugs or combinations are associated with a greater risk. To establish a register to evaluate prospectively the incidence of adverse pregnancy outcomes in women exposed to specific AEDs; to determine whether certain AEDs or combinations were associated with a greater risk; and to determine whether other factors influenced the risk. An Australia-wide, prospective, voluntary, telephone-interview based, observational register. Three groups of pregnant women were enrolled: those with epilepsy taking AEDs, those with epilepsy not taking AEDs, and those taking AEDs for a non-epileptic indication. The pregnancy outcomes were evaluated by follow-up interviews and by reference to hospital and treating doctors' records. Over the first 30 months of the study (till December 2001) 334 eligible women were enrolled, with all states and territories being represented. Two hundred and ninety two pregnancies had been completed, of which 256 (88%) resulted in a healthy live birth, 19 (6.5%) a live birth with a birth defect, four an induced abortion because of a detected malformation on ultrasound, one premature labour with a stillbirth and 12 (4%) spontaneous abortions. Of the completed pregnancies, 269 were exposed to at least one AED during the first trimester. The incidence of birth defects in relation to specific AEDs was: valproate (16.7%), phenytoin (10.5%), lamotrigine (7.7%) and carbamazepine (3.3%), none of which was significantly different from that in women with epilepsy not taking an AED (4.3%, n.s.). The dose of valproate taken was higher in pregnancies with BD compared to those without (mean 2081 mg vs. 1149 mg, p<0.0001). The incidence of folate supplementation being taken prior to conception did not differ for pregnancy outcomes with or without BD (70% vs. 66%, n.s.). The model for the Australian Pregnancy Register appears to be successful, with strong enrolment from all regions over the first 30 months. The study is prospective and includes reference to all new AEDs approved in Australia over the past decade. Analysis of the pregnancy outcomes to date may reveal early trends, but numbers are still to small for any definitive conclusions to be made regarding the relative risk in pregnancy of individual AEDs.
    Journal of Clinical Neuroscience 09/2003; 10(5):543-9. · 1.25 Impact Factor
  • Article: Clinical drug trials and the role of the nurse.
    Louise Rath, Alison Hitchcock, Marion Oakley, Janet Graham
    Australian nursing journal (July 1993) 06/2003; 10(10):19-21.
  • Article: The internal control group in a register of antiepileptic drug use in pregnancy
    [show abstract] [hide abstract]
    ABSTRACT: The aim of this study was to determine how valid 68 first-trimester pregnancies of untreated epileptic women would prove as an internal control group for investigating foetal malformation rates in 709 simultaneously collected antiepileptic drug-exposed pregnancies in an Australian register of pregnancies in epileptic women. We carried out comparisons of values for parameters relating to personal details, obstetric aspects, and epilepsies prior to and during pregnancy in the drug-exposed and drug-unexposed pregnancies, with observations on subpopulations within the drug-unexposed group. Statistically significant (p < 0.05) differences existed for only seven of more than 50 parameters compared. None of these seven parameters had a statistically significant influence on foetal malformation rates in the whole dataset. In 23 of the 65 epileptic pregnancies unexposed to antiepileptic drugs, therapy had been ceased shortly prior to pregnancy and was often resumed after the first trimester. In the remaining 42, therapy had been ceased earlier, often despite continuing seizures. Planned withdrawal of therapy did not appear to produce additional hazards for mothers and foetuses in the former subgroup. In the data collection studied, there did not appear to be evidence of statistically significant differences between untreated pregnancies and treated epileptic pregnancies that would be likely to invalidate the former group as an internal control for the latter, at least when assessing foetal malformation rates.
    Journal of Clinical Neuroscience.
  • Article: Australian pregnancy registry of women taking antiepileptic drugs
    45(11):1466.
  • Article: The Australian antiepileptic drug in pregnancy register: Aspects of data collection and analysis
    [show abstract] [hide abstract]
    ABSTRACT: Internal comparisons using the data of the Australian Register of Antiepileptic Drugs in Pregnancy as of November 2005, and comparisons with Australian population data, were carried out. It was found that (i) except for under-representation of mothers of Asian origin, the demography of the register population was reasonably representative of the Australian situation; (ii) except for more pregnancies terminated for foetal malformation, malformation rates were similar in retrospectively and non-retrospectively enrolled pregnancies; (iii) some 21% of foetal malformations would have been excluded by not including malformations first recognised after the neonatal period; and (iv) in practice, the comparator against which malformation rates were expressed made little difference to the rates found. It is desirable to have available such analyses of pregnancy register data before comparing the findings of different registers.
    Journal of Clinical Neuroscience.