Prenatal Paracetamol Exposure and Wheezing in Childhood: Causation or Confounding?

Drug-induced fetal and offspring disorders, beyond birth defects

Studies on drug utilization in western countries disclosed that about nine over ten women use at least one or more drugs during pregnancy. Determining whether a drug is safe or not in pregnant women is a challenge of all times. As a developing organism, the fetus is particularly vulnerable to effects of drugs used by the mother. Historically, research has predominantly focused on birth defects, which represent the most studied adverse pregnancy outcomes. However, drugs can also alter the ongoing process of pregnancy and impede the general growth of the fetus. Finally, adverse drug reactions can theoretically damage all developing systems, organs or tissues, such as the central nervous system or the immune system. This extensive review focuses on different aspects of drug-induced damages affecting the fetus or the newborn/infant, beyond birth defects, which are not addressed here.

Effects of Prenatal Paracetamol Exposure on the Development of Asthma and Wheezing in Childhood: A Systematic Review and Meta-Analysis

The aim of the report was to evaluate whether in utero exposure to paracetamol is associated with risk towards developing respiratory disorders such as asthma and wheeze after birth. MEDLINE (PubMed), EMBASE and Cochrane Library databases were searched for articles published in English to December 2021. The study involved 330,550 women. We then calculated the summary risk estimates and 95% CIs and plotted forest plots using random effect models (DerSimonian-Laird method) and fixed effect models. We also performed a systematic review of the chosen articles and a meta-analysis of studies based on the guidelines outlined in the PRISMA statement. Accordingly, maternal exposure to paracetamol during pregnancy was associated with a significant increased risk of asthma: crude OR = 1.34, 95% CI: 1.22 to 1.48, p < 0.001; and significant increased risk of wheeze: crude OR = 1.31, 95% CI: 1.12 to 1.54, p < 0.002. Results of our study confirmed that maternal paracetamol use in pregnancy is associated with an enhanced risk of asthma and wheezing in their children. We believe paracetamol should be used with caution by pregnant women, and at the lowest effective dose, and for the shortest duration. Long-term use or the use of high doses should be limited to the indications recommended by a physician and with the mother-to-be under constant supervision.

Racing against time: leveraging preclinical models to understand pulmonary susceptibility to perinatal acetaminophen exposures

Over the past decade, clinicians have increasingly prescribed acetaminophen (APAP) for patients in the neonatal intensive care unit (NICU). Acetaminophen has been shown to reduce postoperative opiate burden, and may provide similar efficacy for closure of the patent ductus arteriosus (PDA) as nonsteroidal anti-inflammatory drugs (NSAIDs). Despite these potential benefits, APAP exposures have spread to increasingly less mature infants, a highly vulnerable population for whom robust pharmacokinetic and pharmacodynamic data for APAP are lacking. Concerningly, preclinical studies suggest that perinatal APAP exposures may result in unanticipated adverse effects that are unique to the developing lung. In this review, we discuss the clinical observations linking APAP exposures to adverse respiratory outcomes and the preclinical data demonstrating a developmental susceptibility to APAP-induced lung injury. We show how clinical observations linking perinatal APAP exposures to pulmonary injury have been taken to the bench to produce important insights into the potential mechanisms underlying these findings. We argue that the available data support a more cautious approach to APAP use in the NICU until large randomized controlled trials provide appropriate safety and efficacy data.

Association between paracetamol use during pregnancy and perinatal outcomes: Prospective NISAMI cohort

BACKGROUND

Paracetamol is widely used to manage fever and pain during pregnancy worldwide. However, paracetamol may affect the pregnant woman and fetus, once this drug crosses the placental barrier after therapeutic doses and may impair fetal liver function, affecting fetus growth and development. Thus, this study aimed to investigate the association between paracetamol use during pregnancy and perinatal outcomes as preterm birth, low birth weight, and small for gestational age.

METHODS AND FINDINGS

Data from 760 pregnant women within the NISAMI Cohort between June 2012 and February 2014 were analyzed. Logistic regression was used to estimate the association among paracetamol use during pregnancy and preterm birth, low birth weight, and small for gestational age. Multivariate analyses were adjusted for socioeconomic, maternal, pregnancy, and newborn covariates. Around 14% of women were exposed to paracetamol during pregnancy. A decrease in paracetamol use throughout pregnancy was observed. Lower risk of low birth weight in infants born to women exposed to the drug (OR 0.21; IC 95% 0.01-0.99) was found. Paracetamol use during pregnancy was not statistically associated with preterm birth or small for gestational age.

CONCLUSIONS

The findings of this study do not suggest an increased risk of perinatal outcomes. However, it should not be assumed that paracetamol is a risk-free medication and its use must be rational.

Effect of acetaminophen use during pregnancy on adverse pregnancy outcomes: a systematic review and meta-analysis

INTRODUCTION

A high number of women are exposed to acetaminophen during pregnancy worldwide. This drug safety during pregnancy regarding preterm birth, birth weight, and fetal development has not been well described. This study investigated the effect of acetaminophen use during pregnancy on selected adverse pregnancy outcomes.

AREAS COVERED

Databases were searched to identify studies reporting the effects of acetaminophen use during pregnancy on preterm birth, low birth weight, and small for gestational age. The studies' quality was assessed by the Newcastle-Ottawa Scale and the Methodological Index for Non-Randomized Studies. Relative risk with 95% confidence intervals of each outcome was estimated using a fixed or random-effects model. Six studies were included for final review, four cohort and two case-control studies. We found no increased risk of preterm birth (RR 0.97; 95% CI 0.59-1.58), and decreased risks of low birth weight (RR 0.65; 95% CI 0.59-0.72) and small for gestational age (RR 0.69; 95% CI 0.50-0.97). Acetaminophen exposure during the third trimester revealed non-significantly in the outcomes.

EXPERT OPINION

Exposure to acetaminophen during pregnancy appears to not increase the risk of the outcomes analyzed. However, there is a lack of information regarding the exposure dose and frequency of acetaminophen use.

Paracetamol exposure and asthma: What does the evidence say? An overview of systematic reviews

OBJECTIVE

To conduct an umbrella review collating the existing evidence to determine whether there is an association between exposure of Paracetamol in-utero or in infancy and the development of childhood Asthma.

METHODS

In this review, systematic reviews with or without meta-analysis that reported the association between paracetamol and asthma in children were included. To identify relevant reviews, a search was performed in the electronic databases PubMed, the Cochrane Library, and Ovid MEDLINE. The protocol was registered in PROSPERO CRD42020156023. A separate search was conducted for primary studies from the last 5 years not yet included in systematic reviews reporting the association from January 2016 to March 2021.

RESULTS

The electronic searches identified 1966 review titles. After the removal of 493 duplicates, 1475 titles and abstracts were screened against the eligibility criteria. Full-text screening yielded six systematic reviews to be included in this review. The search for primary studies in the last 5 years yielded 1214 hits, out of which 5 studies were found suitable for inclusion. Three of them, that were not included in the systematic reviews, and have been summarised in this paper. The odds ratios (ORs) for the outcome of asthma in offspring of mothers with prenatal paracetamol consumption in any trimester were 1.28 (1.13-1.39) and 1.21 (1.02-1.44). For first trimester exposures, they were 1.12 (0.99-1.27), 1.39 (1.01-1.91), and 1.21 (1.14-1.28), for the second or third trimester, they were 1.49 (1.37-1.63) and 1.13 (1.04-1.23). For the third trimester only, the figure was 1.17 (1.04-1.31). Of the six reviews included, 1 had a low risk of bias, 2 had an unclear risk while 3 had a high risk of bias assessed using the ROBIS tool. There was no significant increased risk of asthma with early infancy exposure. The inter-study heterogeneity varied from I²  = 41% to I²  = 76% across reviews. In the primary studies, the OR for prenatal exposure ranged from 1.12 (0.25-4.98) to 4.66 (1.92-11.3) and for infancy exposure was 1.56 (1.06-2.30). All three included primary studies were adjudged to be of high quality using the Newcastle Ottawa scale.

CONCLUSIONS

There is a modest association between paracetamol exposure in-utero and the future development of asthma. Exposure in infancy has a less consistant association. All the studies done thus far are observational in nature, with their inherent biases. Further research, preferably randomized controlled trials are recommended to answer this pertinent question.

Recurrent wheezing during the first 3 years of life in a birth cohort of moderate-to-late preterm infants

BACKGROUND

Data addressing short- and long-term respiratory morbidity in moderate-late preterm infants are limited. We aim to determine the incidence of recurrent wheezing and associated risk and protective factors in these infants during the first 3 years of life.

METHODS

Prospective, multicenter birth cohort study of infants born at 32⁺⁰ to 35⁺⁰  weeks' gestation and followed for 3 years to assess the incidence of physician-diagnosed recurrent wheezing. Allergen sensitization and pulmonary function were also studied. We used multivariate mixed-effects models to identify risk factors associated with recurrent wheezing.

RESULTS

A total of 977 preterm infants were enrolled. Rates of recurrent wheezing during year (Y)1 and Y2 were similar (19%) but decreased to 13.3% in Y3. Related hospitalizations significantly declined from 6.3% in Y1 to 0.75% in Y3. Independent risk factors for recurrent wheezing during Y2 and Y3 included the following: day care attendance, acetaminophen use during pregnancy, and need for mechanical ventilation. Atopic dermatitis on Y2 and male sex on Y3 were also independently associated with recurrent wheezing. Palivizumab prophylaxis for RSV during the first year of life decreased the risk or recurrent wheezing on Y3. While there were no differences in rates of allergen sensitization, pulmonary function tests (FEV_0.5 ) were significantly lower in children who developed recurrent wheezing.

CONCLUSIONS

In moderate-to-late premature infants, respiratory symptoms were associated with lung morbidity persisted during the first 3 years of life and were associated with abnormal pulmonary function tests. Only anti-RSV prophylaxis exerted a protective effect in the development of recurrent wheezing.

Migraine Treatment in Pregnant Women Presenting to Acute Care: A Retrospective Observational Study

OBJECTIVE

To assess the acute treatment of pregnant women presenting to a hospital with migraine.

BACKGROUND

Migraine is a common problem in pregnancy; however, migraine treatment is challenging in pregnant women for fears of medication teratogenicity and lack of data in this population. To date, no study has directly explored physician practices for treatment of acute migraine in pregnant women.

METHODS

We conducted a retrospective chart review of medication administration for pregnant women who presented to an acute care setting with a migraine attack and received neurology consultation between 2009 and 2014.

RESULTS

We identified 72 pregnant women with migraine who were treated with pain medications. Fifty-one percent (37/72) were in the third trimester of pregnancy, 39% (28/72) in the second trimester, and 10% (7/72) in the first trimester. Thirty-two percent (23/72) had not tried any acute medications at home before coming to the hospital, and 47% (34/72) presented in status migrainosus. Patients received treatment in the hospital for a median of 23 hours (interquartile range = 5-45 hours). The most common medications prescribed were metoclopramide in 74% (53/72) of patients (95% confidence interval [CI] 62-82%) and acetaminophen in 69% (50/72) of patients (95% CI 58-79%). Metoclopramide was administered along with diphenhydramine in 81% (44/53) of patients (95% CI 71-91%). Acetaminophen was the most frequent medicine administered first (53%, 38/72). Patients were often treated with butalbital (35%, 25/72) or opioids (30%, 22/72), which were used as second- or third-line treatments in 29% of patients (20/72). Thirty-eight percent (27/72) received an intravenous (IV) fluid bolus, 24% received IV magnesium (17/72), and 6% (4/72) had peripheral nerve blocks performed.

CONCLUSIONS

While the majority of pregnant women with acute migraine received medications considered relatively safe in pregnancy, there was variation in treatment choice and sequence. Some acute medications considered potentially hazardous for fetal health and less effective for migraine (opioids and butalbital) were used frequently, whereas other treatments that may have low teratogenic risk (nerve blocks, IV fluid boluses, and triptans) were used less or not at all. These results indicate a need for developing guidelines and protocols to standardize acute treatment of migraine in pregnancy.

Long-term adverse effects of paracetamol - a review

Paracetamol (acetaminophen) is the most commonly used drug in the world, with a long record of use in acute and chronic pain. In recent years, the benefits of paracetamol use in chronic conditions has been questioned, notably in the areas of osteoarthritis and lower back pain. Over the same period, concerns over the long-term adverse effects of paracetamol use have increased, initially in the field of hypertension, but more recently in other areas as well. The evidence base for the adverse effects of chronic paracetamol use consists of many cohort and observational studies, with few randomized controlled trials, many of which contradict each other, so these studies must be interpreted with caution. Nevertheless, there are some areas where the evidence for harm is more robust, and if a clinician is starting paracetamol with the expectation of chronic use it might be advisable to discuss these side effects with patients beforehand. In particular, an increased risk of gastrointestinal bleeding and a small (~4 mmHg) increase in systolic blood pressure are adverse effects for which the evidence is particularly strong, and which show a degree of dose dependence. As our estimation of the benefits decreases, an accurate assessment of the harms is ever more important. The present review summarizes the current evidence on the harms associated with chronic paracetamol use, focusing on cardiovascular disease, asthma and renal injury, and the effects of in utero exposure.

Prenatal paracetamol use and asthma in childhood: A systematic review and meta-analysis

OBJECTIVES

Some studies have suggested that prenatal paracetamol exposure might associate with the risk of child asthma. However, other studies have not confirmed this result. Therefore, we conducted a meta-analysis to investigate their relationship.

METHODS

Two authors searched Pubmed and Embase databases up to June 2016. The strength of the association was calculated with the OR and respective 95% CIs. The random-effects model was chosen to calculate the pooled OR.

RESULTS

A total of 13 articles of more than 1,043,109 individuals were included in the meta-analysis. A statistically significant association between prenatal paracetamol exposure and child asthma risk was found. The data showed that prenatal paracetamol exposure could increase the risk of child asthma (OR=1.19; 95% CI, 1.12-1.27; P<0.00001) in a random-effect model. Six studies reported paracetamol exposure during the first trimester of pregnancy. We found that paracetamol exposure during the first trimester of pregnancy was associated with increased risk of child asthma (OR=1.21; 95% CI, 1.14-1.28; P<0.00001). Furthermore, we observed that paracetamol exposure during the 2-3 trimesters of pregnancy was also associated with child asthma risk (OR=1.13; 95% CI, 1.04-1.23; P=0.005).

CONCLUSIONS

This study suggested that prenatal paracetamol exposure was significantly associated with the increased risk of child asthma.

Perinatal and neonatal use of paracetamol for pain relief

Paracetamol (acetaminophen) is the most widely used drug to treat pain or fever in pregnant women or neonates, but its pharmacokinetics (PK) and pharmacodynamics (PD) warrant a focused analysis. During pregnancy, there is an important increase in paracetamol clearance. Consequently, it is reasonable to anticipate that the analgesic effect of paracetamol will decrease faster, whereas higher doses may result in even higher oxidative toxic metabolites. Therefore, most peripartal PD data relate to multimodal analgesia strategies. In neonates, weight/size is the most relevant covariate of paracetamol PK. This resulted in proposed dosing regimens containing higher doses than currently prescribed in the label for term neonates. Using adequate dosing, paracetamol is a poor procedural analgesic, is effective for mild-to-moderate pain, and has morphine-sparing effects. Short-term safety has been well documented, and there is active research investigating the potential association between paracetamol exposure and atopy, fertility, and neurobehavior.

Prenatal exposures and the development of childhood wheezing illnesses

PURPOSE OF REVIEW

To critically evaluate and summarize studies published between July 2015 and June 2016 linking prenatal exposures and the onset of childhood wheezing illnesses and to discuss future research directions in this field.

RECENT FINDINGS

The aggregated evidence indicates a consistent detrimental effect of prenatal exposure to parental smoking, outdoor air pollution, and maternal stress on childhood wheezing illnesses. Less consistent evidence suggests an adverse impact of maternal obesity during pregnancy and prenatal exposure to antibiotics on these outcomes. There is insufficient evidence to support an association between in-utero exposure to acetaminophen or prenatal levels of specific nutrients (such as vitamin D, folic acid, or polyunsaturated fatty acids) and childhood wheezing illnesses.

SUMMARY

Several common potentially modifiable prenatal exposures appear to be consistently associated with childhood wheezing illnesses (e.g. parental smoking, outdoor air pollution, and maternal stress). However, the effect of many other prenatal exposures on the onset of childhood wheezing illnesses remains unclear. The existing scientific evidence from the past year does not allow us to make any new recommendations on primary prevention measures. Intervention studies will best demonstrate whether changing the prenatal environment can prevent childhood wheezing illnesses and asthma.

Paracetamol and morphine for infant and neonatal pain; still a long way to go?

INTRODUCTION

Pharmacologic pain management in newborns and infants is often based on limited scientific data. To close the knowledge gap, drug-related research in this population is increasingly supported by the authorities, but remains very challenging. This review summarizes the challenges of analgesic studies in newborns and infants on morphine and paracetamol (acetaminophen). Areas covered: Aspects such as the definition and multimodal character of pain are reflected to newborn infants. Specific problems addressed include defining pharmacodynamic endpoints, performing clinical trials in this population and assessing developmental changes in both pharmacokinetics and pharmacodynamics. Expert commentary: Neonatal and infant pain management research faces two major challenges: lack of clear biomarkers and very heterogeneous pharmacokinetics and pharmacodynamics of analgesics. There is a clear call for integral research addressing the multimodality of pain in this population and further developing population pharmacokinetic models towards physiology-based models.

The association between paracetamol and asthma is still under debate

OBJECTIVE

To analyse the relationship between paracetamol and asthma.

DATA SOURCES

An English literature search using electronic search engines (PubMed and EMBASE) was conducted.

STUDY SELECTIONS

Articles published in peer-review journals, from 1990 to December 2015 were included. To perform the search for the most suitable and representative articles, keywords were selected ("asthma," "paracetamol" and "acetaminophen"). The evidence level was rated according to the criteria of the Oxford Centre For Evidence-Based Medicine.

RESULTS

The exposure to paracetamol during pregnancy was analysed in several cohort studies, showing an association between the prenatal exposure to paracetamol with suffering from asthma or presence of wheezing in childhood, especially for persistent wheezing. Nevertheless, a recent study concluded that the relationship between asthma and paracetamol is explained, at least in part, by confounding factors. Several works have also associated the exposure to paracetamol in the first years of life or in adults with the development of childhood asthma. Several pathophysiological mechanisms are known that could explain this relationship, such as the glutathione pathway, the decrease in the release of Th1 cytokines that are normally produced during febrile episodes, which would then lead to a predominance of Th2 cytokines, the cytotoxic effect of paracetamol for pneumocytes, a modulator effect on the activity of myeloperoxidase, as well as the possible antigenic effect of paracetamol, mediated by IgE.

CONCLUSIONS

There are many arguments that suggest a relationship between the use of paracetamol with the appearance of asthmatic symptoms, however the evidence is inconclusive.

Managing Migraine During Pregnancy and Lactation

While over half of women with migraine report improvement during pregnancy, having a history of migraine may increase the chance of negative health outcomes. The state of pregnancy increases the risk of several dangerous secondary headache disorders, especially those associated with hypertensive disorders of pregnancy, and providers need to know the red flags to diagnose and treat emergently. Non-pharmacological migraine treatments can be instituted in advance of pregnancy as many are considered the safest options during pregnancy, but understanding the safety of medications and dietary supplements ensures appropriate care for the refractory migraine patient. New controversy exists over the safety of several historically routine and safe migraine treatment options in pregnancy, such as magnesium, acetaminophen, ondansetron, and butalbital. While it is not clear if breastfeeding decreases the postpartum recurrence of migraine, understanding safe treatment options during lactation can allow women to continue breastfeeding while achieving migraine relief.

Key paediatric messages from Amsterdam

The Paediatric Assembly of the European Respiratory Society (ERS) maintained its high profile at the 2015 ERS International Congress in Amsterdam. There were symposia on preschool wheeze, respiratory sounds and cystic fibrosis; an educational skills workshop on paediatric respiratory resuscitation; a hot topic session on risk factors and early origins of respiratory diseases; a meet the expert session on paediatric lung function test reference values; and the annual paediatric grand round. In this report the Chairs of the Paediatric Assembly's Groups highlight the key messages from the abstracts presented at the Congress.