Kate Smolina

Trends and Determinants of Prescription Drug Use during Pregnancy and Postpartum in British Columbia, 2002–2011: A Population-Based Cohort Study

Purpose To describe trends, patterns, and determinants of prescription drug use during pregnancy and postpartum. Methods This is a retrospective, population-based study of all women who gave birth between January 2002 and 31 December 2011 in British Columbia, Canada. Study population consisted of 225,973 women who had 322,219 pregnancies. We examined administrative datasets containing person-specific information on filled prescriptions, hospitalizations, and medical services. Main outcome measures were filled prescriptions during pregnancy and postpartum. We used logistic regressions to examine associations between prescription drug use and maternal characteristics. Results Approximately two thirds of women filled a prescription during pregnancy, increasing from 60% in 2002 to 66% in 2011. The proportion of pregnant women using medicines in all three trimesters of pregnancy increased from 20% in 2002 to 27% in 2011. Use of four or more different types of prescription drug during at least one trimester increased from 8.4% in 2002 to 11.7% in 2011. Higher BMI, smoking during pregnancy, age under 25, carrying multiples, and being diagnosed with a chronic condition all significantly increased the odds of prescription drug use during pregnancy. Conclusions The observed increase in the number of prescriptions and number of different drugs being dispensed suggests a trend in prescribing practices with potentially important implications for mothers, their neonates, and caregivers. Monitoring of prescribing practices and further research into the safety of most commonly prescribed medications is crucial in better understanding risks and benefits to the fetus and the mother.

Sex Disparities in Post-Acute Myocardial Infarction Pharmacologic Treatment Initiation and Adherence Problem for Young Women

Background—The prevalence of the use of secondary prevention cardiovascular medications is lower among women than men, but it is unclear if this is a result of lower treatment initiation among women or lower treatment adherence. We aimed to map the treatment pathway for survivors of acute myocardial infarction (AMI) by sex and age. Methods and Results—This retrospective population-based cohort study used linked administrative data sets in British Columbia (2004–2011), which include health care, prescription drugs, sociodemographic, and mortality information. The study cohort included all individuals admitted to hospital for AMI in 2007–2009 and survived for 1 year after hospital discharge. Patients were evaluated for whether they initiated and then subsequently filled prescriptions angiotensin-converting enzyme inhibitors, &bgr;-blockers, and statins. More than two thirds of AMI survivors initiated treatment on all appropriate medications, given their contraindications, within 2 months of discharge. Younger men were significantly more likely than younger women to initiate appropriate treatment (adjusted odds ratio, 1.38; 95% confidence interval, 1.10–1.75). By the end of 1 year after discharge, only one third of all AMI survivors filled all appropriate prescriptions for at least 80% of the year. There was no significant difference in adherence to medication therapy between women and men. Conclusions—The majority of AMI survivors either discontinue treatment or do not refill their prescriptions consistently. Women <55 years are significantly less likely to be on optimal therapy by the end of 1 year after discharge, which is driven by a sex disparity in treatment initiation and not treatment adherence.

Postpartum domperidone use in British Columbia: a retrospective cohort study

BACKGROUND Domperidone is commonly used off-label to stimulate milk production in mothers who have low milk supply. The aim of this study was to describe trends, patterns and determinants of postpartum domperidone use. METHODS This is a retrospective, population-based study involving all women with a live birth between Jan. 1, 2002, and Dec. 31, 2011, in the province of British Columbia. We examined administrative data sets containing person-specific information on filled prescriptions and use of medical services, and we used logistic regression to examine associations between domperidone use and maternal characteristics. RESULTS The study population consisted of 225 532 women with 320 351 live births. The prevalence of postpartum domperidone use more than doubled between 2002 and 2011. In 2011, 1 in 3 women with a preterm birth and 1 in 5 women with a full-term birth were prescribed domperidone in the first 6 months postpartum. Women who were older, had a higher body mass index, had a chronic disease, were first-time mothers, delivered more than 1 baby (multiple pregnancy), had a preterm birth or had a cesarian delivery were more likely to fill a postpartum domperidone prescription. INTERPRETATION We found an increase in postpartum domperidone use over a 10-year period. More research is needed on maternal and infant health outcomes.

The association between domperidone and ventricular arrhythmia in the postpartum period.

The aim of this study is to examine the relationship between domperidone (commonly used off‐label for lactation stimulation), ventricular arrhythmia and all‐cause mortality during the postpartum period.

Postpartum Hemorrhage and Use of Serotonin Reuptake Inhibitor Antidepressants in Pregnancy.

OBJECTIVE: To examine whether using selective serotonin reuptake inhibitors and selective serotonin–norepinephrine reuptake inhibitors in pregnancy is associated with an increased risk of postpartum hemorrhage. METHODS: We conducted a population-based cohort study including 225,973 women with 322,224 pregnancies in British Columbia, Canada, between 2002 and 2011. Women were categorized according to whether they had late-pregnancy exposure (at least 15 of the last 30 days of pregnancy), midpregnancy exposure (in the last 5 months of pregnancy but not the final 30 days), or no exposure. Postpartum hemorrhage was identified using International Classification of Diseases (9th and 10th Revisions) codes in data on all hospitalizations. RESULTS: We found an increased risk of postpartum hemorrhage associated with exposure to an serotonin–norepinephrine reuptake inhibitor in the final month of pregnancy after adjustment for potential confounders (n=1,390; adjusted odds ratio [OR] 1.76, 95% confidence interval [CI] 1.47–2.11, respectively) corresponding to 4.1 (95% CI 2.4–5.7) additional cases of postpartum hemorrhage per 100 people treated. There was no significant relationship between selective serotonin reuptake inhibitor use in the final month of pregnancy and postpartum hemorrhage (n=6,637; adjusted OR 1.09, 95% CI 0.98–1.21), except when confining the cohort to women with complete body mass index (BMI) information (n=235,031 [73%]) and controlling for BMI (adjusted OR 1.14, 95% CI 1.01–1.28) or when controlling for variables that are possibly on the causal pathway (adjusted OR 1.13, 95% CI 1.02–1.26). Midpregnancy exposure to a serotonin–norepinephrine reuptake inhibitor (n=242) or a selective serotonin reuptake inhibitor (n=1,507) was not associated with an increased postpartum hemorrhage risk. CONCLUSION: Serotonin–norepinephrine reuptake inhibitor exposure in late pregnancy was associated with a 1.6- to 1.9-fold increased risk of postpartum hemorrhage.

Geographic Variations in Prescription Opioid Dispensations and Deaths Among Women and Men in British Columbia, Canada.

Objectives:We quantify patterns in prescription opioid dispensations to individuals who suffered a prescription opioid-related death. In addition, we examine the relationship between opioid dispensations and prescription opioid-related deaths in geographic regions of British Columbia (BC). Methods:We used population-based administrative data on prescription drug dispensations to identify patterns in prescription opioid dispensations to individuals who suffered a prescription opioid-related death. We also computed the quantity of prescription opioids dispensed (morphine equivalents) in small geographic regions in BC from 2004 to 2013. We identified prescription opioid-related deaths in these small geographic areas using mortality data from BC Vital Statistics and investigated the relationship between rates of prescription opioid dispensing and rates of prescription opioid death in small geographic areas in BC by sex. We examined differences in our results when limiting opioid dispensations to strong opioids and weak opioids. Results:Many individuals who suffered a prescription opioid-related death did not have an active opioid prescription in the 60 days before death (46% of women and 71% of men). Rates of prescription opioid dispensing and opioid-related deaths vary substantially across geographic regions in BC. The area-level relationship between rate of prescription opioid dispensing and rate of unintentional prescription opioid-related death is positive and statistically significant for both men and women (P<0.001). This relationship holds when opioid prescribing is limited to strong opioids. Conclusion:Targeted efforts to reduce high levels of opioid prescribing in BC, particularly dispensations of strong opioids and codeine, may substantially reduce opioid-related harms.

Sensitivity and specificity of administrative mortality data for identifying prescription opioid–related deaths

Background: Comprehensive systems for surveilling prescription opioid–related harms provide clear evidence that deaths from prescription opioids have increased dramatically in the United States. However, these harms are not systematically monitored in Canada. In light of a growing public health crisis, accessible, nationwide data sources to examine prescription opioid–related harms in Canada are needed. We sought to examine the performance of 5 algorithms to identify prescription opioid–related deaths from vital statistics data against data abstracted from the Office of the Chief Coroner of Ontario as a gold standard. Methods: We identified all prescription opioid–related deaths from Ontario coroners’ data that occurred between Jan. 31, 2003, and Dec. 31, 2010. We then used 5 different algorithms to identify prescription opioid–related deaths from vital statistics death data in 2010. We selected the algorithm with the highest sensitivity and a positive predictive value of more than 80% as the optimal algorithm for identifying prescription opioid–related deaths. Results: Four of the 5 algorithms had positive predictive values of more than 80%. The algorithm with the highest sensitivity (75%) in 2010 improved slightly in its predictive performance from 2003 to 2010. Interpretation: In the absence of specific systems for monitoring prescription opioid–related deaths in Canada, readily available national vital statistics data can be used to study prescription opioid–related mortality with considerable accuracy. Despite some limitations, these data may facilitate the implementation of national surveillance and monitoring strategies.

Long-term sedative use among community-dwelling adults: a population-based analysis

BACKGROUND Chronic use of benzodiazepines and benzodiazepine-like sedatives (z-drugs) presents substantial risks to people of all ages. We sought to assess trends in long-term sedative use among community-dwelling adults in British Columbia. METHODS Using population-based linked administrative databases, we examined longitudinal trends in age-standardized rates of sedative use among different age groups of community-dwelling adults (age ≥ 18 yr), from 2004 to 2013. For each calendar year, we classified adults as nonusers, short-term users, or long-term users of sedatives based on their patterns of sedative dispensation. For calendar year 2013, we applied cross-sectional analysis and estimated logistic regression models to identify health and socioeconomic risk factors associated with long-term sedative use. RESULTS More than half (53.4%) of long-term users of sedatives in British Columbia are between ages 18 and 64 years (young and middle-aged adults). From 2004 to 2013, long-term sedative use remained stable among adults more than 65 years of age (older adults) and increased slightly among young and middle-aged adults. Although the use of benzodiazepines decreased during the study period, the trend was offset by equal or greater increases in long-term use of z-drugs. Being an older adult, sick, poor and single were associated with increased odds of long-term sedative use. INTERPRETATION Despite efforts to stem such patterns of medication use, long-term use of sedatives increased in British Columbia between 2004 and 2013. This increase was driven largely by increased use among middle-aged adults. Future deprescribing efforts that target adults of all ages may help curb this trend.

Determinants of trends in prescription opioid use in British Columbia, Canada, 2005-2013.

To explore the determinants of total opioid consumption in a Canadian province, and to examine patterns of opioid dispensations by sex, age, and income quintile.

Trends and sex differences in prescription opioid deaths in British Columbia, Canada

Increasing rates of prescription opioid-related death are well documented in Ontario (ON) but little is known about prescription opioid-related harms in other Canadian provinces. Using administrative mortality data from 2004 to 2013, we found that rates of prescription opioid-related death in British Columbia (BC) were higher but more stable than published rates for ON over the same period. Methadone was involved in approximately 25% of the prescription opioid-related deaths in BC. The majority of prescription opioid-related deaths among men and women were unintentional. Men had higher overall rates of prescription opioid-related deaths in BC; women had lower rates of prescription opioid-related deaths but a larger proportion of them were suicides. Efforts to reduce prescription opioid-related deaths must consider sex differences in patterns of prescription opioid use and associated harms.