Preeclampsia in pregnancy and later use of antihypertensive drugs

We explored the association between preeclampsia and later use of antihypertensive drugs in a population-based study with data from the Medical Birth Registry of Norway and the Norwegian Prescription Database. The study cohort consisted of 980,000 women having 2.1 million pregnancies during 1967–2012. Hazard ratios (HRs) with 95 % confidence intervals (95 % CI) were estimated in multivariate time-dependent Cox proportional hazards regression models. Overall, the HR of later use of antihypertensive drugs was 2.0 (95 % CI 2.0–2.0) in women with one preeclamptic pregnancy compared to women without preeclamptic pregnancies. The HR increased by increasing number of preeclamptic pregnancies, both term and preterm pregnancies. In women with two or more preeclamptic pregnancies, the HR was 2.8 (2.7–3.0). The overall HR after 40 years of follow-up for women with one preeclamptic pregnancy was 1.3 (1.2–1.4) and for two or more preeclamptic pregnancies the HR was 1.6 (1.1–2.1). The first 5 years after the first birth, the HR of being dispensed antihypertensive drugs was higher in preterm [8.4 (7.7–9.1)] than term preeclamptic pregnancies [4.3(4.0–4.6)]. However, after 10 years, this difference was no longer present. The HR of later use of antihypertensive drugs increased with the number of preeclamptic pregnancies, and in the first 10 years the HR was higher after a preterm than a term preeclamptic pregnancy. Although the HR decreased with time since first birth, the risk was still elevated after 40 years.

Tapering from Methadone or Buprenorphine during Pregnancy: Maternal and Neonatal Outcomes in Norway 1996-2009

BACKGROUND

The tapering of methadone or buprenorphine during pregnancy is an understudied and controversial issue. The aim of this study was to determine to what extent women tapered their opioid medication dose during pregnancy and what the neonatal outcomes were for those who tapered compared to the women who did not.

METHODS

The study was a mixed prospective/retrospective national cohort study of 123 Norwegian women in opioid maintenance treatment (OMT) during pregnancy and their neonates. A standardized questionnaire was administered to the women and medical information that could be used for verification was collected from hospitals and municipalities.

RESULTS

Two of the women came off the OMT-medication during pregnancy and another 15% tapered their OMT-medication dose more than 50%. The birth weights of methadone-exposed neonates of the women who tapered more than 50% were significantly higher than for the methadone-exposed neonates of the women tapering between 11 and 50%. No other significant differences were found.

CONCLUSION

Pregnant women in OMT who taper their OMT-medication dose should be monitored closely. We need studies that document the maternal well-being and fetal safety of maternal tapering of the OMT-medication during pregnancy.

Self-reported data on medicine use in the Norwegian Mother and Child cohort study compared to data from the Norwegian Prescription Database

<p><em>Aims:</em> To study information on prescribed drug use (opioids, antidepressants and benzodiazepines (BZD)) recorded in the Norwegian Prescription Database (NorPD) and to compare this information with selfreported drug use among pregnant women in the Norwegian Mother and Child Cohort Study (MoBa).</p><p><em>Materials and methods:</em> The study population consisted of 28 479 women who participated in MoBa and who answered all questionnaires in pregnancy and whose pregnancy started after 1 March 2004. Data on dispensed drugs in NorPD were extracted for three different time windows: a) the pregnancy period, b) 30 days prior to pregnancy in addition to pregnancy, c) 60 days prior to pregnancy in addition to pregnancy. Data on self- reported drug use in MoBa were used as the reference standard in the validity analysis. Sensitivity and specificity were calculated.</p><p><em>Results:</em> Sensitivity of drug use as recorded in NorPD for the pregnancy period was highest for antidepressants (66.9%) and BZD-antiepileptics (100%) and lowest for BZD-anxiolytics (44.8%) and BZDhypnotics (27.8%). Expansion of the time windows for dispensed drugs in the NorPD to include intervals 30 and 60 days before pregnancy led to higher sensitivity, but lower specificity of all classes of drugs. For opioids, sensitivity increased from 48.8% to 53.6%, while specificity decreased from 98.7 to 97.6%. For antidepressants and BZD-anxiolytics, specificity decreased for both from 99.7 to 99.4%.</p><p><em>Conclusion:</em> Using self-reported data as reference standard, the prescription data provides valid information on current exposures to BZD-antiepileptics and antidepressants in pregnant women if time windows are selected with adequate consideration depending on the investigated problem. However, validity is lower for other benzodiazepines and opioids.</p>

Factors associated with dropout among patients in opioid maintenance treatment (OMT) and predictors of re-entry. A national registry-based study

BACKGROUND

Retention in treatment is often highlighted as one of the key indicators of success in opioid maintenance treatment (OMT).

AIMS

To identify factors associated with long-term retention in opioid maintenance treatment and to analyse predictors of subsequent treatment episodes.

METHODS

Treatment retention and re-entry were examined for a national cohort of patients admitted to OMT in Norway in the period 1997-2003. Multivariate Cox regression models were used to investigate factors associated with treatment dropout 18months after treatment entry.

RESULTS

The 18month retention rate among patients admitted to OMT in Norway (n=2431) was 65.8% (n=1599). Dropout from OMT within 18months was associated with younger age (HR 0.97 [0.96-0.98]), high levels of general pre-treatment criminal offences (HR 1.66 [1.32-2.09]) and having drug-related offences during the 30days prior to dropout (HR 1.80 [1.36-2.38]). Of the patients who dropped out (n=832), 42.7% (n=355) were re-engaged in subsequent treatment episodes. Pre-treatment criminal offences were associated with increased odds for treatment re-entry, whereas being younger and having drug-related offences during the first OMT episode were associated with lower odds for re-engagement in OMT. Gender was not associated with treatment dropout and re-entry.

CONCLUSION

High levels of pre-treatment criminal offences and drug offences during the 30days prior to dropout were associated with treatment dropout. Efforts to increase support services to these patients may contribute to higher rates of retention in OMT.

Prenatal exposure to antidepressants and language competence at age three: results from a large population-based pregnancy cohort in Norway

OBJECTIVE

To examine the association between maternal use of selective serotonin reuptake inhibitors (SSRI) in pregnancy and language competence in their children at age three taking into account maternal symptoms of anxiety and depression.

DESIGN

Population-based prospective pregnancy cohort study.

SETTING

The Norwegian Mother and Child Cohort Study; recruited pregnant women from 1999 through 2008.

POPULATION

45,266 women with 51,748 singleton pregnancies.

METHODS

The association between short- or long-term use of SSRI during pregnancy and language competence in the child was investigated using multinomial logistic regression with three outcome categories: long, complicated sentences, fairly complete sentences and language delay.

MAIN OUTCOME MEASURES

Children's language competence at age three measured by maternal report on a validated language grammar scale.

RESULTS

Women reported use of SSRI in 386 (0.7%) pregnancies. Of these, 161 (42%) reported long-term use. Compared with children whose mothers took no SSRI, using the best language category as the reference, adjusted relative risk ratios (RRR) of having fairly complete sentences were 1.21 (95% CI 0.85-1.72) and 2.28 (1.54-3.38) for short- and long-term SSRI use, respectively. The adjusted RRRs of language delay were 0.86 (0.42-1.76) and 2.30 (1.21-4.37). Symptoms of anxiety and depression in pregnancy were independently related to language delay, adjusted RRR 1.25 (1.03-1.50) and 1.83 (1.40-2.40) for short- and long-term symptoms, respectively.

CONCLUSIONS

Prolonged use of SSRI during pregnancy was associated with lower language competence in children by age three independently of depression. Having symptoms of depression throughout pregnancy had an independent effect.

Chronic pain and use of opioids: a population-based pharmacoepidemiological study from the Norwegian prescription database and the Nord-Trøndelag health study

In previous studies on prescription patterns of opioids, accurate data on pain are missing, and previous epidemiological studies of pain lack accurate data on opioid use. The present linkage study, which investigates the relationship between pain and opioid use, is based on accurate individual data from the complete national Norwegian prescription database and the Nord-Trøndelag health study 3, which includes about 46,000 people. Baseline data were collected in 2006 to 2008, and the cohort was followed up for 3 years. Of 14,477 people who reported chronic nonmalignant pain, 85% did not use opioids at all, 3% used opioids persistently, and 12% used opioids occasionally. Even in the group reporting severe or very severe chronic pain, the number not using opioids (2680) was far higher than the number who used opioids persistently (304). However, three quarters of people using opioids persistently reported strong or very strong pain in spite of the medication. Risk factors for the people with chronic pain who were not persistent opioid users at baseline to use opioids persistently 3 years later were occasional use of opioids, prescription of >100 defined daily doses per year of benzodiazepines, physical inactivity, reports of strong pain intensity, and prescription of drugs from 8 or more Anatomical Therapeutic Chemical groups. The study showed that most people having chronic nonmalignant pain are not using opioids, even if the pain is strong or very strong. However, the vast majority of patients with persistent opioid use report strong or very strong pain in spite of opioid treatment.

Prescribing of drugs for attention-deficit hyperactivity disorder in opioid maintenance treatment patients in Norway

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is a risk factor for the development of substance use disorders. Treatment of ADHD with psychostimulants in patients on opioid maintenance treatment (OMT) has been restricted in Norway. We examined the use of prescribed drugs for ADHD in OMT patients and assessed co-medication with other psychotropics.

METHODS

Data were drawn from the nationwide Norwegian Prescription Database (NorPD), which includes all prescriptions filled at pharmacies. The study population included subjects ≥18 years on OMT during 2008-2010.

RESULTS

In 2010, 6,116 patients received OMT and 2.8% of these also received ADHD drugs. This percentage is seven times greater than that in the gender- and age-specific general population of Norway. The prevalence was higher in the youngest patients, while there was no gender difference. Methylphenidate was the most commonly used drug for ADHD in OMT patients, followed by atomoxetine. 60% of OMT patients filled at least one prescription for antidepressants, anxiolytics or hypnotics, and percentages were similar for users and non-users of ADHD drugs.

CONCLUSION

Treatment with ADHD drugs was higher in OMT patients than expected from the general population, but was relatively low compared to the prevalence of ADHD in patients with substance use disorders reported in the literature.

Multiple prescribers in older frequent opioid users--does it mean abuse?

BACKGROUND

Obtaining analgesic narcotics from multiple prescribers is sometimes called 'doctor-shopping,' implying abuse. If the use of multiple prescribers can be used as an indicator for abuse, it would be a convenient way to study abuse in large populations.

OBJECTIVE

To assess multiple prescribers as an indicator of abuse by relating quantity of opioids obtained by older Norwegians to number of prescribers.

METHODS

Data were obtained from the Norwegian Prescription database which includes all prescriptions filled in Norwegian pharmacies. The study population consisted of people aged 70-89 who filled five or more prescriptions for weak or for strong opioids in 2008.

RESULTS

In 2008, 4,268 persons filled five or more prescriptions for strong opioids and 19,675 for weak opioids. More than 30% had three or more prescribers. Over half of strong opioids users and 72% of weak opioid users had medication-use-periods of over 40 weeks. For strong opioids, increasing DDDs/week was found with increasing number of prescribers. When cancer/palliative care patients were excluded, the mean DDDs/week level for strong opioids was much lower, and little association with number of prescribers remained. For weak opioids, little association between mean DDDs/week and number of prescribers was found.

CONCLUSIONS

This study demonstrated that the increasing quantities of strong opioids with increasing number of prescribers are largely due to treatment of cancer/palliative care patients. While the use of multiple prescribers can be a red flag for problematic medication use, it cannot be considered synonymous with 'doctor-shopping' or abuse.

Driving under the influence (DUI) among patients in opioid maintenance treatment (OMT): a registry-based national cohort study

AIMS

To investigate convictions for driving under the influence (DUI) before, during and after opioid maintenance treatment (OMT) and to examine factors associated with convictions for DUI during treatment.

DESIGN, SETTING AND PARTICIPANTS

Treatment data on all patients who started OMT in Norway between 1997 and 2003 (n = 3221) were cross-linked with national criminal records using unique person identifiers. Patients were followed over a 9-year period, before, during and in periods out of opioid maintenance treatment.

MEASUREMENTS

Data were formal charges leading to convictions recorded during four different time-periods: 3 years prior to application, waiting-list, in-treatment and in periods out of treatment.

FINDINGS

During OMT, convictions for DUI were reduced by almost 40% compared with pre-application levels. The conviction rate for DUI for males in the pre-application period was 9.59 per 100 person-years (PY) and for females, 3.44 per 100 PY. During OMT, rates of DUI convictions were reduced to 5.97 per 100 PY among men and to 1.09 per 100 PY among women. However, when estimating the effect of OMT on convictions for DUI, the interaction between gender and exposure to OMT was not statistically significant. Patients who remained in continuous treatment had fewer convictions for DUI during treatment compared with patients in discontinuous treatment. Compared with patients having no road traffic convictions during the pre-application period, patients with two or more pre-application convictions for DUI had higher odds [odds ratio (OR) = 3.69 (2.30-5.93)] for further convictions for DUI during OMT.

CONCLUSION

In Norway, patients receiving opioid maintenance treatment (OMT) have reduced convictions for driving under the influence (DUI) compared with their pre-treatment levels. Being male and having a previous history of several convictions for DUI were found to be important risk factors for convictions for DUI during OMT.

Breastfeeding reduces the need for withdrawal treatment in opioid-exposed infants

AIM

To examine the rate and duration of breastfeeding in a cohort of women in opioid maintenance treatment (OMT) in Norway, as well as the effect of breastfeeding on the incidence and duration of neonatal abstinence syndrome (NAS).

METHODS

A national cohort of 124 women treated with either methadone or buprenorphine during pregnancy, and their neonates born between 1999 and 2009, was evaluated in three study parts. A standardized questionnaire was administered, and medical information from the hospitals and municipalities were collected to confirm self-reported data.

RESULTS

There were high initiation rates of breastfeeding (77%) for women in OMT, but also high rates of early cessation of breastfeeding. Breastfed neonates exposed to methadone prenatally had significantly lower incidence of NAS requiring pharmacotherapy (53% vs. 80%), and both the whole group of infants and the methadone-exposed neonates needed shorter pharmacological treatment of NAS (p < 0.05) than neonates who were not breastfed.

CONCLUSION

Breastfed neonates exposed to OMT medication prenatally, and methadone-exposed newborns in particular, have lower incidence of NAS and require shorter pharmacotherapy for NAS than infants who are not breastfed. The results add to the evidence regarding the benefits of breastfeeding for neonates prenatally exposed to OMT medications.

A day-by-day investigation of changes in criminal convictions before and after entering and leaving opioid maintenance treatment: a national cohort study

BACKGROUND

Opioid maintenance treatment (OMT) is associated with reduced crime among heroin users, but little is known about how crime changes during different phases of treatment. The aim of this study was to investigate changes in criminal convictions on a day-to-day basis before and after entry or discharge from OMT.

METHODS

National cohort study of all patients (n = 3221) in OMT in Norway 1997-2003. Patients were followed over a 9-year period, before, during, and after treatment. Criminal convictions were studied on a day-to-day basis in relation to treatment status. A time-continuous estimate of the probability of convictions within the population for all days during observation was calculated.

RESULTS

Changes in convictions were evident before changes of treatment status. During the 3 years prior to OMT, the convictions rate was approximately 0.4% per day. Prior to OMT, convictions decreased to about 0.2% per day on the day of treatment initiation. During the weeks before dropping out of treatment, convictions increased. The patterns during periods of transition were the same across gender, age and pre-treatment conviction-levels.

CONCLUSIONS

Changes in convictions often occurred prior to changes in treatment status. Reductions in criminal convictions were found in the period before entry (or re-entry) to OMT, and increases in criminal activity were found in the months prior to treatment interruption.

A pharmacoepidemiological cohort study of subjects starting strong opioids for nonmalignant pain: a study from the Norwegian Prescription Database

Clinical studies of short duration have demonstrated that strong opioids improve pain control in selected patients with chronic nonmalignant pain. However, high discontinuation rates and dose escalation during long-term treatment have been indicated. The aim of the present study was to determine discontinuation rates, dose escalation, and patterns of co-medication with benzodiazepines. The Norwegian Prescription Database provides complete national data at an individual level on dispensed drugs. A complete national cohort of new users of strong opioids was followed up for 5 years after initiation of therapy with strong opioids. Of the 17,248 persons who were new users of strong opioids in 2005, 7229 were dispensed a second prescription within 70 days and were assumed to be intended long-term users. A total of 1233 persons in the study cohort were still on opioid therapy 5 years later. This equals 24% of the study cohort who were still alive. Of the participants, 21% decreased their annual opioid dose by 25% or more, whereas 21% kept a stable dose (± 24%) and 34% more than doubled their opioid dose from the first to the fifth year. High annual doses of opioids were associated with high annual doses of benzodiazepines at the end of follow-up. It is an issue of major concern that large dose escalation is common during long-term treatment, and that that high doses of opioids are associated with high doses of benzodiazepines. These findings make it necessary to question whether the appropriate patient population receives long-term opioid treatment.

Effects of preconceptional paternal drug exposure on birth outcomes: cohort study of 340 000 pregnancies using Norwegian population-based databases

AIMS

We aimed to explore associations between drugs dispensed to the father prior to conception and pregnancy outcomes, such as pre-term birth, perinatal mortality, foetal growth retardation and birth defects.

METHODS

In this cohort study, two population-based registries, the Medical Birth Registry of Norway and the Norwegian Prescription Database, were linked. The study cohort consisted of 340 000 pregnancies in 2004-10. The association between specific drugs dispensed to the fathers during the last 3 months prior to conception and pregnancy outcomes was explored by estimating odds ratios (ORs) using multivariate logistic regression.

RESULTS

About one quarter (26%) of the fathers were dispensed at least one drug during the last 3 months prior to conception and 1.3% were dispensed at least one drug requiring special attention. Overall, the odds of different adverse pregnancy outcomes were not increased when the father had been dispensed drugs, i.e. the OR and 95% confidence intervals (CIs) for any birth defect when the fathers had been dispensed any drug were 0.99 (0.94, 1.0). When the fathers had been dispensed diazepam we found increased risk of perinatal mortality and growth retardation, with OR and 95% CIs of 2.2 (1.2, 3.9) and 1.4 (1.2, 1.6), respectively.

CONCLUSIONS

Large studies are necessary to reveal increased risk of rare outcomes as specific birth defects. Our study did not indicate that paternal drug exposure is an important risk factor for adverse pregnancy outcomes.

Association between prescribing hypnotics for parents and children in Norway

OBJECTIVE

To describe the dispensing of the hypnotic alimemazine to children aged 0-3 years and investigate the association between dispensing of alimemazine to children and dispensed hypnotics to their parents.

DESIGN

An observational cohort study linking information from the Medical Birth Registry of Norway and the Norwegian Prescription Database. Hypnotics dispensed to parents in a 1-year period before pregnancy was associated with dispensed alimemazine for children aged 0-3 years.

PATIENTS AND SETTING

All children born in Norway in 2008 (N=59 325) and their mothers and fathers were included.

MAIN OUTCOME MEASURES

Dispensed alimemazine to children during the first 3 years of life.

RESULTS

Three percent of children received alimemazine. Dispensed hypnotics to mothers increased the risk of the child receiving a prescription for alimemazine, OR of 2.3 (1.7-3.0) for boys and 1.7 (1.2-2.4) for girls. When both parents had been dispensed prescriptions for hypnotics, the risk increased nearly threefold. A dispensed alimemazine prescription was also associated with dispensed prescriptions for antidepressants to both mother and father, mother's smoking, the child's gender and child's prescriptions for antibiotics, respiratory drugs and dermatological steroids.

CONCLUSIONS

Dispensed alimemazine to children under 3 was associated with parents' previous use of hypnotics, indicating that factors other than the child's health influence the use of hypnotic drugs in infancy and toddler years. The frequent usage of alimemazine in children below 3 years and the association with parents' use of hypnotics should concern prescribing doctors.

Adherence, persistence and switch rates for anticholinergic drugs used for overactive bladder in women: data from the Norwegian Prescription Database

OBJECTIVE

To investigate the pattern of use of anticholinergic drugs for overactive bladder among women in Norway with regard to persistence, adherence and switch rates.

DESIGN

Observational study.

SETTING AND SAMPLE

Data from the Norwegian Prescription Database on prescriptions for tolterodine, solifenacin, darifenacin and fesoterodine filled in Norwegian pharmacies from 1 January 2004 to 31 December 2010.

METHODS AND MAIN OUTCOME MEASURES

Data from the database were analysed at an individual level, and drug persistence, discontinuation rates and switch rates during a follow-up period of 365 days after the first prescription were calculated.

RESULTS

Overall 1-year persistence for new users was 38.0%. Within the same period, a total of 10.3% switched from the index drug to another drug in the same group, whereas 51.7% discontinued without switching. Users of solifenacin and tolterodine were somewhat more persistent than users of darifenacin and fesoterodine. Persistence was lowest (20.9%) in the age group 18-39 years, increased with age and was highest in the age groups 70-79 years and 80 years and above (43.5 and 43.3%, respectively). In total, 31.9% filled only one prescription of the drug and, of these, only one of four women switched to another drug. The proportion who were adherent during treatment was 60.4%.

CONCLUSIONS

The discontinuation rate for anticholinergic drugs for overactive bladder in women is high. The reasons why patients stop using them remain obscure but could be related both to a limited clinical effect and an unacceptable adverse effect burden.

Drug exposure: inclusion of dispensed drugs before pregnancy may lead to underestimation of risk associations

OBJECTIVES

To assess the impact of exposure misclassification on risk associations when using prescription databases as the source for drug exposure in pregnancy by applying results from a validation analysis of exposure classification.

STUDY DESIGN AND SETTING

Linkage of data on 27,656 participants in the Norwegian Mother and Child Cohort Study (MoBa) with the Norwegian Prescription Database (NorPD). Exposure to selective serotonin reuptake inhibitors (SSRIs) was defined by dispensed drugs during pregnancy including different time windows before pregnancy. The validity of NorPD data was estimated using self-reported use in MoBa as the reference standard. We applied the results from the validation analysis on data from a Nordic study on SSRI use in pregnancy and risk of persistent pulmonary hypertension in the newborn.

RESULTS

Sensitivity increased and specificity decreased when the time window in NorPD was expanded before pregnancy. Using the same time window as in the Nordic study (+90 days before pregnancy), for use in early pregnancy, the odds ratio (OR) corrected for misclassification was 2.6 compared with the OR of 1.6 in the Nordic study.

CONCLUSION

Expansion of the time window to include intervals before pregnancy can lead to lower specificity and underestimation of risk associations.

Reimbursement of analgesics for chronic pain

BACKGROUND

The prevalence of chronic non-malignant pain in Norway is between 24% and 30%. The proportion of the population using opioids for non-malignant pain on a long-term basis is around 1%. The purpose of our study was to investigate how many were prescribed analgesics on reimbursable prescription under reimbursement code -71 (chronic non-malignant pain) in 2009 and 2010, which analgesics were prescribed and whether prescribing practices were in accordance with national guidelines.

MATERIAL AND METHOD

We retrieved pseudonymised data from the National Prescription Database on all those who received drugs with reimbursement code -71 in 2009 and 2010. The data contain information on drug, dosage, formulation, reimbursement code and date of issue.

RESULTS

90,731 patients received reimbursement for drugs indicated for chronic non-malignant pain in 2010. Of these, 6,875 were given opioids, 33,242 received paracetamol, 25,865 non-steroid inflammatory drugs (NSAIDs), 20,654 amitryptiline and 16,507 gabapentin. Oxycodone was the most frequently prescribed opioid, followed by buprenorphine, tramadol and codeine/paracetamol. Of those who were prescribed opioids, 4,047 (59%) received mainly slow-release opioids, 2,631 (38%) also received benzodiazepines and 2,418 (35%) received benzodiazepine-like sleep medications.

CONCLUSION

The number of patients who received analgesics and opioids on reimbursable prescriptions was low compared to the proportion of the population with chronic pain and the proportion using opioids long-term. 38% of those reimbursed for opioids also used benzodiazepines, which is contrary to official Norwegian guidelines.

Prescription drug use among pregnant women in opioid Maintenance Treatment

AIMS

This study describes the use of prescribed drugs among women in opioid maintenance treatment (OMT) prior to, and during, pregnancy.

DESIGN

This cohort study was based on data from two nationwide databases: the Medical Birth Registry of Norway and the Norwegian Prescription Database.

SETTING

Norway, 2004-2010.

PARTICIPANTS

OMT drugs were dispensed to 138 women with 159 pregnancies.

MEASUREMENTS

All prescription drugs dispensed to women in OMT three months prior to, and during, pregnancy were studied. Amounts of benzodiazepines, z-hypnotics and opioid analgesics dispensed during pregnancy were studied and bivariate analysis was used to study neonatal outcomes of OMT pregnancies with and without such co-medication.

FINDINGS

The prevalence of prescription drug use by pregnant OMT women was high both during the three-month period prior to (69%), and during (81%), pregnancy. The proportion of pregnant women that was dispensed anti-infectives (48%) and/or drugs acting on the nervous system (45%) during any time in pregnancy was especially high. In 21%, 15% and 13% of the pregnancies the women were dispensed benzodiazepine anxiolytics, opioid analgesics or benzodiazepine hypnotics respectively. Only 5% of the OMT women were dispensed antidepressants. Malformations were significantly more common among children born to mothers in OMT that received co-medication with opioids, benzodiazepines or z-hypnotics.

CONCLUSIONS

A higher proportion of women in opioid maintenance treatment in Norway use prescription drugs prior to, and during, pregnancy than pregnant women in the general population. Co-medication with drugs with abuse potential may increase the risk of adverse pregnancy outcomes and this need to be further addressed.

Neonatal outcomes following in utero exposure to methadone or buprenorphine: a National Cohort Study of opioid-agonist treatment of Pregnant Women in Norway from 1996 to 2009

BACKGROUND

In Norway, most opioid-dependent women are in opioid maintenance treatment (OMT) with either methadone or buprenorphine throughout pregnancy. The inclusion criteria for both medications are the same and both medications are provided by the same health professionals in any part of the country. International studies comparing methadone and buprenorphine in pregnancy have shown differing neonatal outcomes for the two medications.

METHOD

This study compared the neonatal outcomes following prenatal exposure to either methadone or buprenorphine in a national clinical cohort of 139 women/neonates from 1996 to 2009.

RESULTS

After adjusting for relevant covariates, buprenorphine-exposed newborns had larger head circumferences and tended to be heavier and longer than methadone-exposed newborns. The incidence of neonatal abstinence syndrome (NAS) and length of treatment of NAS did not differ between methadone- and buprenorphine-exposed newborns. There was little use of illegal drugs and benzodiazepines during the pregnancies. However, the use of any drugs or benzodiazepines during pregnancy was associated with longer lasting NAS-treatment of the neonates.

CONCLUSIONS

The clinical relevance of these findings is that both methadone and buprenorphine are acceptable medications for the use in pregnancy, in line with previous studies. If starting OMT in pregnancy, buprenorphine should be considered as the drug of choice, due to more favorable neonatal growth parameters. Early confirmation of the pregnancy and systematic follow-up throughout the pregnancy are of importance to encourage the women in OMT to abstain from the use of tobacco, alcohol, illegal drugs or misuse of prescribed drugs.

Benzodiazepine and z-hypnotic use in Norwegian elderly, aged 65-79

Purpose: Benzodiazepines/z-hypnotics (BZD-Z) guidelines suggest that elderly people ought to use anxiolytic benzodiazepines (BZD) and z-hypnotics only at low dose and only for a short time, and that hypnotic BZD not should be used at all. Since the elderly aged 65-79 tend to be recently retired but still in relatively good health, they may have different needs for BZD-Z than those older or younger. Our objective is to examine BZD-Z use in this age group.Methods: The study population consisted of Norwegians, aged 65-79, who filled prescriptions for anxiolytic BZD, hypnotic BZD and/or z-hypnotics in 2004-2009. The quantities prescribed were in daily defined doses (DDD), and 100 DDD/year was deemed excessive.Results: More than a quarter of the population received at least one BZD-Z prescription each year. Half of those received more than 100 DDD/year and a quarter received over 250 DDD/year, with these proportions increasing year by year. All three subgroups of BZD-Z showed increasing use with age and all except anxiolytic BZD showed increasing proportions of users using more than 100 DDD/year with age.Conclusions: Substantial numbers of elderly aged 65-79 receive prescriptions for BZD-Z, more with increasing age, and greater amounts per user. Guidelines are clearly ignored. While a rigid enforcement of guidelines/rules is not the answer, allowing the status quo to continue shows lack of respect for guidelines.

Concomitant medication among persistent opioid users with chronic non-malignant pain

BACKGROUND

Recent guidelines for opioid treatment of chronic non-malignant pain discourage co-medication with benzodiazepines and benzodiazepine-related hypnotics, whereas co-medication with non-opioid analgesics and co-analgesics may offer a beneficial opioid sparing effect, and is recommended. The aim of this study was to describe 1-year periodic prevalence of co-medication with benzodiazepines, benzodiazepine-related hypnotics, non-opioid analgesics, co-analgesics and antidepressants in persistent opioid users with chronic non-malignant pain.

METHODS

The study is based on data from the Norwegian Prescription Database, covering all drugs dispensed to outpatients in 2008. Concomitant medication levels were compared between users in two definitions of persistent opioid use, all Norwegian adults dispensed opioids in 2008 and the Norwegian background population.

RESULTS

Of the Norwegian adult population studied, 1.2% met the criteria of persistent opioid use based on prescription pattern and prescription level. Sixty percent of persistent opioid users were dispensed a benzodiazepine or benzodiazepine-related hypnotic in amounts indicating regular use, with 15% dispensed a high amount of both classes. Sixty-two percent of persistent opioid users were dispensed one or more non-opioid analgesics, 47% an antidepressant and 33% were dispensed an antiepileptic drug.

CONCLUSION

Approximately 60% of persistent opioid users also receive benzodiazepines or benzodiazepine-related hypnotics in amounts indicating regular use. This is in conflict with recent guidelines for the treatment of chronic non-malignant pain and may indicate that these users are at an increased risk of developing problematic opioid use.