Acetaminophen in Pregnancy:A Population-Level Drug-Utilization Study of Prescription-Based Acetaminophen Use Among Pregnant Women in Denmark From 2001 to 2023

Acetaminophen is the most used analgetic drug for pain management during pregnancy. A recent academic controversy concerns the safety of acetaminophen during pregnancy related to a potentially increased risk of adverse neurodevelopmental effects. We investigated the population-level trends in prescription-based use of acetaminophen among pregnant women in Denmark between 2001 and 2023. Prescription-based sals of acetaminophen among pregnant women and comparison groups were retrieved from ‘eSundhed’, a publicly available dataset curated by the Danish Health Authorities. The number of prescription-based drug users per 1000 pregnant women increased slightly from 2001 to 2012 (3.9 to 6.5 per 1000) and 2015 to 2023 (52 to 76 per 1000), interrupted by a drastic increase in 2013/2014. Acetaminophen use among pregnant women (2023: 76 per 1000) was lower than in women in an age-matched comparison group (137 per 1000) and in women 12–3 months prior to pregnancy (124 per 1000). Time trends did not notably differ between age groups or comparison groups. Prescription-based acetaminophen sales among pregnant women increased by 50% from 2015 to 2023. A general shift in the prescription pattern towards a substantial increase in prescription-based exposure was observed following legislation changes in 2013, restricting sales of large packages to prescription.</p

An analysis of the level of evidence behind treatments recommended by the Danish Medicines Council

Objectives: We aimed to investigate the quality of evidence and the expected added clinical value of treatments recommended by the Danish Medicines Council (DMC). Study design: This was an observational study. Methods: The DMC prepares reports on drugs considered for possible new standard treatments in Danish hospitals. These reports evaluate the available evidence on efficacy and safety. The quality of evidence is systematically rated by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) criteria, and estimates of added clinical value are presented. The recommendations take into account expected economic implications of new treatments. The publicly available reports up until December 29, 2021, were downloaded from the DMC Web page. Reports on drugs marked “recommended” were included. Data on quality of evidence, expected clinical value, and economic implications were imputed in a Microsoft Excel spreadsheet. Results: Seventy-nine reports were included in the analysis. In 79% of these, the quality of evidence was rated low (24%) or very low (55%), whereas no recommendations were based on evidence rated as high quality. Three (5%) of recommended treatments were expected to add large clinical value. Conclusions: Most recommendations by the DMC are based on evidence formally rated as low or very low quality by GRADE, and no recommendations were based on evidence rated as high quality. The added clinical value of the treatments was often not documented and rarely large. Continued attention to improve the clinical evidence behind national recommendations is necessary.</p

Improving the transparency of meta-analyses with interactive web applications

Increased transparency in study design and analysis is one proposed solution to the perceived reproducibility crisis facing science. Systematic review and meta-analysis-through which individual studies on a specific association are ascertained, assessed for quality and quantitatively combined-is a critical process for building consensus in medical research. However, the conventional publication model creates static evidence summaries that force the quality assessment criteria and analytical choices of a small number of authors onto all stakeholders, some of whom will have different views on the quality assessment and key features of the analysis. This leads to discordant inferences from meta-analysis results and delayed arrival at consensus. We propose a shift to interactive meta-analysis, through which stakeholders can take control of the evidence synthesis using their own quality criteria and preferred analytic approach-including the option to incorporate prior information on the association in question-to reveal how their summary estimate differs from that reported by the original analysts. We demonstrate this concept using a web-based meta-analysis of the association between genetic variation in a key tamoxifen-metabolising enzyme and breast cancer recurrence in tamoxifen-treated women. We argue that interactive meta-analyses would speed consensus-building to the degree that they reveal invariance of inferences to different study selection and analysis criteria. On the other hand, when inferences are found to differ substantially as a function of these choices, the disparities highlight where future research resources should be invested to resolve lingering sources of disagreement.</p

Statin use before and after the KDIGO Lipids in chronic kidney disease guideline:A population-based interrupted time series analysis

In November 2013, the Kidney Disease: Improving Global Outcomes Clinical Practice Guideline for Lipid Management in Chronic Kidney Disease was published, recommending statins for all individuals 50 years or older with an estimated glomerular filtration rate below 60 ml/min/1.73 m2 to lower the risk of major cardiovascular events. We quantified the prevalence of statin use among the target population before and after the guideline publication in a large Danish cohort of individuals with an estimated glomerular filtration rate below 60 ml/min/1.73 m2, to investigate the effect of the guideline, but found no difference in the prevalence of statin use prior to and after the guideline publication.</p

Implementation and clinical benefit of DPYD genotyping in a Danish cancer population

BACKGROUND: In 2020, the European Medicines Agency recommended testing patients for dihydropyrimidine dehydrogenase (DPD) deficiency before systemic treatment with fluoropyrimidines (FP). DPD activity testing identifies patients at elevated risk of severe FP-related toxicity (FP-TOX). The two most used methods for DPD testing are DPYD genotyping and DPD phenotyping (plasma uracil concentration). The primary objective of this study was to compare the overall frequency of overall grade ≥3 FP-TOX before and after the implementation of DPYD genotyping.PATIENTS AND METHODS: Two hundred thirty Danish, primarily gastrointestinal cancer patients, were DPYD-genotyped before their first dose of FP, and blood was sampled for post hoc assessment of P-uracil. The initial dose was reduced for variant carriers. Grade ≥3 FP-TOX was registered after the first three treatment cycles of FP. The frequency of toxicity was compared to a historical cohort of 492 patients with post hoc determined DPYD genotype from a biobank.RESULTS: The frequency of overall grade ≥3 FP-TOX was 27% in the DPYD genotype-guided group compared to 24% in the historical cohort. In DPYD variant carriers, DPYD genotyping reduced the frequency of FP-related hospitalization from 19% to 0%. In the control group, 4.8% of DPYD variant carriers died due to FP-TOX compared to 0% in the group receiving DPYD genotype-guided dosing of FP. In the intervention group, wild-type patients with uracil ≥16 ng/ml had a higher frequency of FP-TOX than wild-type patients with uracil &lt;16 ng/ml (55% versus 28%).CONCLUSIONS: We found no population-level benefit of DPYD genotyping when comparing the risk of grade ≥3 FP-TOX before and after clinical implementation. We observed no deaths or FP-related hospitalizations in patients whose FP treatment was guided by a variant DPYD genotype. The use of DPD phenotyping may add valuable information in DPYD wild-type patients.</p

Assessing techniques for quantifying the impact of bias due to an unmeasured confounder:An applied example

Purpose: To compare the magnitude of bias due to unmeasured confounding estimated from various techniques in an applied example. Patients and Methods: We examined the association between dibutyl phthalate (DBP) and incident estrogen receptor (ER)-positive breast cancer in a Danish nationwide cohort (N=1,122,042). Cox regression analyses were adjusted for age and active drug compounds contributing to DBP exposure. We estimated the hazard ratios (HRs) that would have been observed had one of the DBP sources been unmeasured and calculated the strength of confounding by comparing to the fully adjusted HR. We performed a quantitative bias analysis (QBA) of the “unmeasured” confounder, using external information to specify the bias parameters. Upper bounds on the bias were estimated and E-values were calculated. Results: The adjusted HR for incident ER-positive breast cancer among women with high-level (≥10,000 cumulative milligrams) versus no DBP exposure was 2.12 (95% confidence interval 1.12 to 4.05). Removing each DBP source in isolation resulted in negligible change in the HR. The bias estimates from the QBA ranged from 1.00 to 1.01. The estimated maximum impact of unmeasured confounding ranged from 1.01 to 1.51. E-values ranged from 3.46 to 3.68. Conclusion: The impact of bias due to simulated unmeasured confounding was negligible, in part, because the unmeasured variable was not independent of controlled variables. When a suspected confounder cannot be measured in the study data, our exercise suggests that QBA is the most informative method for assessing the impact. E-values may best be reserved for situations where uncontrolled confounding emanates from an unknown confounder.</p

Phthalate exposure and breast cancer incidence:A danish nationwide cohort study

PURPOSE Phthalate exposure is ubiquitous and especially high among users of drug products formulated with phthalates. Some phthalates mimic estradiol and may promote breast cancer. Existing epidemiologic studies on this topic are small, mostly not prospective, and have given inconsistent results. We estimated associations between longitudinal phthalate exposures and breast cancer risk in a Danish nationwide cohort, using redeemed prescriptions for phthalate-containing drug products to measure exposure. METHODS We ascertained the phthalate content of drugs marketed in Denmark using an internal Danish Medicines Agency ingredient database. We enrolled a Danish nationwide cohort of 1.12 million women at risk for a first cancer diagnosis on January 1, 2005. By combining drug ingredient data with the Danish National Prescription registry, we characterized annual, cumulative phthalate exposure through redeemed prescriptions. We then fit multivariable Cox regression models to estimate associations between phthalate exposures and incident invasive breast carcinoma according to tumor estrogen receptor status. RESULTS Over 9.99 million woman-years of follow-up, most phthalate exposures were not associated with breast cancer incidence. High-level dibutyl phthalate exposure ($ 10,000 cumulative mg) was associated with an approximately two-fold increase in the rate of estrogen receptor-positive breast cancer (hazard ratio, 1.9; 95% CI, 1.1 to 3.5), consistent with in vitro evidence for an estrogenic effect of this compound. Lower levels of dibutyl phthalate exposure were not associated with breast cancer incidence. CONCLUSION Our results suggest that women should avoid high-level exposure to dibutyl phthalate, such as through long-term treatment with pharmaceuticals formulated with dibutyl phthalate.</p

Cohort Profile:The Predictors of Breast Cancer Recurrence (ProBe CaRE) Premenopausal Breast Cancer Cohort Study in Denmark

Purpose The Predictors of Breast Cancer Recurrence (ProBe CaRe) study was established to evaluate modification of tamoxifen (TAM) effectiveness in premenopausal women through reduced activity of TAM-metabolising enzymes. It comprehensively evaluates the effects of pharmacogenetic variants, use of concomitant medications and biomarkers involved in oestrogen metabolism on breast cancer recurrence risk. Participants The ProBe CaRe study was established using resources from the Danish Breast Cancer Group (DBCG), including 5959 premenopausal women diagnosed with stage I-III primary breast cancer between 2002 and 2010 in Denmark. Eligible participants were divided into two groups based on oestrogen receptor alpha (ERα) expression and receipt of TAM therapy, 4600 are classified as ERα+/TAM+ and 1359 are classified as ERα-/TAM-. The ProBe CaRe study is a population-based cohort study nested in a nearly complete source population, clinical, tumour and demographic data were abstracted from DBCG registry data. Linkage to Danish registries allows for abstraction of information regarding comorbid conditions, comedication use and mortality. Formalin-fixed paraffin-embedded tissue samples have been prepared for DNA extraction and immunohistochemical assay. Findings to date To mitigate incorrect classification of patients into specific categories, we conducted a validation substudy. We compared data acquired from registry and from medical record review to calculate positive predictive values (PPVs) and negative predictive values. We observed PPVs near 100% for tumour size, lymph node involvement, receptor status, surgery type, receipt of radiotherapy, receipt of chemotherapy and TAM treatment. We found that the PPVs were 96% (95% CI 83% to 100%) for change in endocrine therapy and 61% (95% CI 42% to 77%) for menopausal transition. Future plans The ProBeCaRe cohort study is well positioned to comprehensively examine pharmacogenetic variants. We will use a Bayesian pathway analysis to evaluate the complete TAM metabolic path to allow for gene-gene interactions, incorporating information of other important patient characteristics.</p