Procedural sedation and analgesia versus general anesthesia for hysteroscopic myomectomy (PROSECCO trial): A multicenter randomized controlled trial

BACKGROUND

Hysteroscopic resection is the first-choice treatment for symptomatic type 0 and 1 fibroids. Traditionally, this was performed under general anesthesia. Over the last decade, surgical procedures are increasingly being performed in an outpatient setting under procedural sedation and analgesia. However, studies evaluating safety and effectiveness of hysteroscopic myomectomy under procedural sedation are lacking. This study aims to investigate whether hysteroscopic myomectomy under procedural sedation and analgesia with propofol is noninferior to hysteroscopic myomectomy under general anesthesia.

METHODS AND FINDINGS

This was a multicenter, randomized controlled noninferiority trial conducted in 14 university and teaching hospitals in the Netherlands between 2016 and 2021. Inclusion criteria were age ≥18 years, maximum number of 3 type 0 or 1 fibroids, maximum fibroid diameter 3.5 cm, American Society of Anesthesiologists class 1 or 2, and having sufficient knowledge of the Dutch or English language. Women with clotting disorders or with severe anemia (Hb < 5.0 mmol/L) were excluded. Women were randomized using block randomization with variable block sizes of 2, 4, and 6, between hysteroscopic myomectomy under procedural sedation and analgesia (PSA) with propofol or under general anesthesia (GA). Primary outcome was the percentage of complete resections, assessed on transvaginal ultrasonography 6 weeks postoperatively by a sonographer blinded for the treatment arm and surgical outcome. Secondary outcomes were the surgeon's judgment of completeness of procedure, menstrual blood loss, uterine fibroid related and general quality of life, pain, recovery, hospitalization, complications, and surgical reinterventions. Follow-up period was 1 year. The risk difference between both treatment arms was estimated, and a Farrington-Manning test was used to determine the p-value for noninferiority (noninferiority margin 7.5% of incomplete resections). Data were analyzed according to the intention-to-treat principle, including a per-protocol analysis for the primary outcome. A total of 209 women participated in the study and underwent hysteroscopic myomectomy with PSA (n = 106) or GA (n = 103). Mean age was 45.1 [SD 6.4] years in the PSA group versus 45.0 [7.7] years in the GA group. For 98/106 women in the PSA group and 89/103 women in the GA group, data were available for analysis of the primary outcome. Hysteroscopic resection was complete in 86/98 women (87.8%) in the PSA group and 79/89 women (88.8%) in the GA group (risk difference -1.01%; 95% confidence interval (CI) -10.36 to 8.34; noninferiority, P = 0.09). No serious anesthesiologic complications occurred, and conversion from PSA to GA was not required. During the follow-up period, 15 serious adverse events occurred (overnight admissions). All were unrelated to the intervention studied. Main limitations were the choice of primary outcome and the fact that our study proved to be underpowered.

CONCLUSIONS

Noninferiority of PSA for completeness of resection was not shown, though there were no significant differences in clinical outcomes and quality of life. In this study, hysteroscopic myomectomy for type 0 and 1 fibroids with PSA compared to GA was safe and led to shorter hospitalization. These results can be used for counseling patients by gynecologists and anesthesiologists. Based on these findings, we suggest that hysteroscopic myomectomies can be performed under PSA in an outpatient setting.

TRIAL REGISTRATION

The study was registered prospectively in the Dutch Trial Register (NTR 5357; registration date: 11 August 2015; Date of initial participant enrollment: 18 February 2016).

Effect of Pessary vs Surgery on Patient-Reported Improvement in Patients With Symptomatic Pelvic Organ Prolapse: A Randomized Clinical Trial

IMPORTANCE

Pelvic organ prolapse is a prevalent condition among women that negatively affects their quality of life. With increasing life expectancy, the global need for cost-effective care for women with pelvic organ prolapse will continue to increase.

OBJECTIVE

To investigate whether treatment with a pessary is noninferior to surgery among patients with symptomatic pelvic organ prolapse.

DESIGN, SETTING, AND PARTICIPANTS

The PEOPLE project was a noninferiority randomized clinical trial conducted in 21 participating hospitals in the Netherlands. A total of 1605 women with symptomatic stage 2 or greater pelvic organ prolapse were requested to participate between March 2015 through November 2019; 440 gave informed consent. Final 24-month follow-up ended at June 30, 2022.

INTERVENTIONS

Two hundred eighteen participants were randomized to receive pessary treatment and 222 to surgery.

MAIN OUTCOMES AND MEASURES

The primary outcome was subjective patient-reported improvement at 24 months, measured with the Patient Global Impression of Improvement scale, a 7-point Likert scale ranging from very much better to very much worse. This scale was dichotomized as successful, defined as much better or very much better, vs nonsuccessful treatment. The noninferiority margin was set at 10 percentage points risk difference. Data of crossover between therapies and adverse events were captured.

RESULTS

Among 440 patients who were randomized (mean [SD] age, 64.7 [9.29] years), 173 (79.3%) in the pessary group and 162 (73.3%) in the surgery group completed the trial at 24 months. In the population, analyzed as randomized, subjective improvement was reported by 132 of 173 (76.3%) in the pessary group vs 132 of 162 (81.5%) in the surgery group (risk difference, -6.1% [1-sided 95% CI, -12.7 to ∞]; P value for noninferiority, .16). The per-protocol analysis showed a similar result for subjective improvement with 52 of 74 (70.3%) in the pessary group vs 125 of 150 (83.3%) in the surgery group (risk difference, -13.1% [1-sided 95% CI, -23.0 to ∞]; P value for noninferiority, .69). Crossover from pessary to surgery occurred among 118 of 218 (54.1%) participants. The most common adverse event among pessary users was discomfort (42.7%) vs urinary tract infection (9%) following surgery.

CONCLUSIONS AND RELEVANCE

Among patients with symptomatic pelvic organ prolapse, an initial strategy of pessary therapy, compared with surgery, did not meet criteria for noninferiority with regard to patient-reported improvement at 24 months. Interpretation is limited by loss to follow-up and the large amount of participant crossover from pessary therapy to surgery.

TRIAL REGISTRATION

Netherlands Trial Register Identifier: NTR4883.

Elective induction of labour and expectant management in late-term pregnancy: A prospective cohort study alongside the INDEX randomised controlled trial

Objective

To assess adverse perinatal outcomes and caesarean section of low-risk women receiving elective induction of labour at 41 weeks or expectant management until 42 weeks according to their preferred and actual management strategy.

Design

Multicentre prospective cohort study alongside RCT.

Setting

90 midwifery practices and 12 hospitals in the Netherlands.

Population

3642 low-risk women with uncomplicated singleton late-term pregnancy.

Main outcome measures

Composite adverse outcome (perinatal death, Apgar score 5′ < 7, NICU admission, meconium aspiration syndrome), composite severe adverse perinatal outcome (all above with Apgar score 5′ < 4 instead of < 7) and caesarean section.

Results

From 2012–2016, 3642 women out of 6088 eligible women for the INDEX RCT, participated in the cohort study for observational data collection (induction of labour n = 372; expectant management n = 2174; unknown preference/management strategy n = 1096).

Adverse perinatal outcome occurred in 1.1 % (4/372) in the induction group versus 1.9 % (42/2174) in the expectant group (adjRR 0.56; 95 %CI: 0.17–1.79), with severe adverse perinatal outcome occurring in 0.3 % (1/372) versus 1.0 % (22/2174), respectively (adjRR 0.39; 95 % CI: 0.05–2.88). There were no stillbirths among all 3642 women; one neonatal death occurred in the unknown preference/management group. Caesarean section rates were 10.5 % (39/372) after induction and 8.9 % (193/2174) after expectant management (adjRR 1.32; 95 % CI: 0.95–1.84).

A higher incidence of adverse perinatal outcome was observed in nulliparous compared to multiparous women. Nulliparous 1.8 % (3/170) in the induction group versus 2.6 % (30/1134) in the expectant management group (adjRR 0.58; 95 % CI 0.14–2.41), multiparous 0.5 % (1/201) versus 1.1 % (11/1039) (adjRR 0.54; 95 % CI 0.07–24.19). One maternal death due to amniotic fluid embolism occurred after elective induction at 41 weeks + 6 days.

Conclusion

In this cohort study among low-risk women receiving the policy of their preference in late-term pregnancy, a non-significant difference was found between induction of labour at 41 weeks and expectant management until 42 weeks in absolute risks of composite adverse (1.1 % versus 1.9 %) and severe adverse (0.3 % versus 1.0 %) perinatal outcome. The risks in this cohort study were lower than in the trial setting. There were no stillbirths among all 3642 women. Caesarean section rates were comparable.

•

No stillbirths in late-term pregnancy (IOL or EM) of 3642 women in INDEX-cohort.

•

Less adverse perinatal outcomes in INDEX-cohort than in trial with comparable risk difference.

•

More women approaching late-term pregnancy prefer EM, not elective induction.

Study protocol for a randomized trial on timely delivery versus expectant management in late preterm small for gestational age pregnancies with an abnormal umbilicocerebral ratio (UCR): the DRIGITAT study

BACKGROUND

The clinical inability to correctly identify late fetal growth restriction (FGR) within a group of fetuses who are identified as small for gestational age (SGA) is an everyday problem for all obstetrician-gynecologists. This leads to substantial overtreatment of healthy small fetuses but also inadequate detection of the growth-restricted fetuses that may benefit from timely delivery. Redistribution of the fetal circulation, signaled by an abnormal ratio of the Doppler velocity flow profiles of the umbilical artery and the middle cerebral artery, more specifically an increased umbilicocerebral ratio (UCR) (or its inverse: a decreased cerebroplacental ratio (CPR)), is an adaptation to chronic hypoxemia and nutritional scarcity with long-term consequences in survivors. The relevance of an abnormal UCR has been signaled extensively, and there is a general consensus that it is a signal of FGR, independent of size, with a strong association with poor outcomes. Yet, in the current literature, no comparisons of a monitoring-delivery strategy based on unfavorable UCR have been published. The objective of the Doppler Ratio In fetal Growth restriction Intervention Trial At (near) Term (DRIGITAT) is to evaluate if the timing of the delivery based on an abnormal UCR in late preterm fetuses identified as SGA improves neurodevelopmental outcomes at 2 years of age.

METHODS

The DRIGITAT study is a national multicenter cohort study of women with singleton pregnancies between 32 and 37 weeks of gestation identified as SGA, with a nested randomized controlled trial (RCT) in case of an abnormal UCR (> 0.8). Recruiting centers are in The Netherlands. In the nested RCT, women are randomized to either immediate induction of labor or expectant management from 34 weeks in case of severely abnormal size (EFW or FAC < p3) and from 36 weeks in case of mildly abnormal size (EFW or FAC p3-p10). The primary outcome measure is the 7-point average difference in the composite cognitive score (CCS) and composite motor score (CMS) on the Bayley-3 at 2 years. Secondary outcome measures include a composite outcome of neonatal morbidity, perinatal mortality, mode of delivery, maternal quality of life, costs, and predictive value of serum biomarkers. Analyses will be by intention to treat. The required sample size is determined for the nested RCT as 185 patients.

DISCUSSION

This study will provide insight into the diagnostic efficacy of UCR measurement in the evaluation of SGA fetuses in order to differentiate the healthy SGA fetus from the growth-restricted fetus and to determine if a fetus with abnormal UCR benefits from early delivery.

TRIAL REGISTRATION

Healthcare Evaluation Netherlands NTR6663 . Registered on 14 August 2017.

Endometrial ablation plus levonorgestrel releasing intrauterine system versus endometrial ablation alone in women with heavy menstrual bleeding: study protocol of a multicentre randomised controlled trial; MIRA2 trial

Background

It is estimated that between 12 to 25% of women who undergo an endometrial ablation for heavy menstrual bleeding (HMB) are dissatisfied after two years because of recurrent menstrual bleeding and/or cyclical pelvic pain, with around 15% of these women ultimately having a hysterectomy. The insertion of a levonorgestrel-releasing intrauterine system (LNG-IUS) immediately after endometrial ablation may inactivate residual untreated endometrium and/or inhibit the regeneration of endometrial tissue. Furthermore, the LNG-IUS may prevent agglutination of the uterine walls preventing intrauterine adhesion formation associated with endometrial ablation. In these ways, insertion of an LNG-IUS immediately after endometrial ablation might prevent subsequent hysterectomies because of persisting uterine bleeding and cyclical pelvic pain or pain that arises de novo. Hence, we evaluate if the combination of endometrial ablation and an LNG-IUS is superior to endometrial ablation alone in terms of reducing subsequent rates of hysterectomy at two years following the initial ablative procedure.

Methods/design

We perform a multicentre randomised controlled trial in 35 hospitals in the Netherlands. Women with heavy menstrual bleeding, who opt for treatment with endometrial ablation and without contraindication for an LNG-IUS are eligible. After informed consent, participants are randomly allocated to either endometrial ablation plus LNG-IUS or endometrial ablation alone. The primary outcome is the hysterectomy rate at 24 months following endometrial ablation. Secondary outcomes include women’s satisfaction, reinterventions, complications, side effects, menstrual bleeding patterns, quality of life, societal costs.

Discussion

The results of this study will help clinicians inform women with HMB who opt for treatment with endometrial ablation about whether concomitant use of the LNG-IUS is beneficial for reducing the need for hysterectomy due to ongoing bleeding and/or pain symptoms.

Trial registration Dutch Trial registration: NL7817. Registered 20 June 2019, https://www.trialregister.nl/trial/7817.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-022-01843-6.

Working conditions in low risk nulliparous women in The Netherlands: are legislation and guidelines a guarantee for a healthy working environment? A cohort study

Objective

Hazardous working conditions increase the risk of adverse pregnancy outcomes. In this study, we examine adherence to legislation and guidelines aimed at improving working conditions in pregnancy.

Methods

Between 2014 and 2016, we recruited a prospective cohort of low-risk nulliparous pregnant women in paid employment or self-employed in 16 community midwifery practices in The Netherlands. Participants completed two questionnaires concerning demographics, education, general health and working conditions between 10–16 and 20–24 weeks of pregnancy. We calculated the proportion of participants with work-related risk factors not in accordance with legislation and/or guidelines.

Results

Of 269 participants included, 214 (80%) completed both questionnaires. At 10–16 weeks 110 (41%) participants and at 20–24 weeks 129 (63%) participants continued to work under circumstances that did not meet recommendations. Employers provided mandated information on work adjustment to 37 (15%) participants and 96 (38%) participants received no information about the potential hazards while working with biological and chemical hazards. Participants with lower educational attainment (aOR 2.2 95%CI 1.3–3.9), or employment in healthcare (aOR 4.5, 95%CI 2.2–9.0), education/childcare and social service (aOR 2.6, 95%CI 1.1–6.0 2),, catering (aOR 3.6, 95%CI 1.1–12) and industry, construction and cleaning (aOR 3.3, 95%CI 1.1–10.3) more often continued work which did not meet recommendations.

Conclusion

There is poor adherence to national legislation and guidelines for safe working in pregnancy in The Netherlands: 50% of the pregnant women worked under hazardous conditions. Given the impact on adverse pregnancy outcomes as well as on the public purse, action to improve compliance must be taken by all stakeholders.

Cost-Effectiveness of perioperative Vaginally Administered estrogen in postmenopausal women undergoing prolapse surgery (EVA trial): study protocol for a multicenter double-blind randomized placebo-controlled trial

BACKGROUND

Surgery for pelvic organ prolapse (POP) is associated with high recurrence rates. The costs associated with the treatment of recurrent POP are huge, and the burden from women who encounter recurrent POP, negatively impacts their quality of life. Estrogen therapy might improve surgical outcome for POP due to its potential beneficial effects. It is thought that vaginal estrogen therapy improves healing and long-term maintenance of connective tissue integrity. Hence, this study aims to evaluate the cost-effectiveness of perioperative vaginal estrogen therapy in postmenopausal women undergoing POP surgery.

METHODS

The EVA trial is a multi-center double-blind randomized placebo-controlled trial conducted in the Netherlands comparing the effectiveness and costs-effectiveness of vaginal estrogen therapy. This will be studied in 300 postmenopausal women undergoing primary POP surgery, with a POP-Q stage of ≥ 2. After randomization, participants administer vaginal estrogen cream or placebo cream from 4 to 6 weeks preoperative until 12 months postoperative. The primary outcome is subjective improvement of POP symptoms at 1 year follow-up, measured with the Patient Global Impression of Improvement (PGI-I) scale. Secondary outcomes are POP-Q anatomy in all compartments, re-interventions, surgery related complications, general and disease specific quality of life, sexual function, signs and complaints of vaginal atrophy, vaginal pH, adverse events, costs, and adherence to treatment. Follow up is scheduled at 6 weeks, 6 months and 12 months postoperative. Data will be collected using validated questionnaires and out-patient visits including gynecological examination performed by an independent gynecologist.

DISCUSSION

This study investigates whether perioperative vaginal estrogen will be cost-effective in the surgical treatment of POP in postmenopausal women. It is hypothesized that estrogen therapy will show a reduction in recurrent POP symptoms and a reduction in reoperations for POP, with subsequent improved quality of life among women and cost savings. Trial registrationNetherlands Trial Registry: NL6853; registered 19-02-2018, https://www.trialregister.nl/trial/6853 . EudraCT: 2017-003144-21; registered: 24-07-2017.

Marketing Authorization Applications Made to the European Medicines Agency in 2018-2019: What was the Contribution of Real-World Evidence?

Information derived from routinely collected real‐world data has for a long time been used to support regulatory decision making on the safety of drugs and has more recently been used to support marketing authorization submissions to regulators. There is a lack of detailed information on the use and types of this real‐world evidence (RWE) as submitted to regulators. We used resources held by the European Medicines Agency (EMA) to describe the characteristics of RWE included in new marketing authorization applications (MAAs) and extensions of indication (EOIs) for already authorized products submitted to the EMA in 2018 and 2019. For MAAs, 63 of 158 products (39.9%) contained RWE with a total of 117 studies. For 31.7% of these products, the RWE submitted was derived from data collected before the planned authorization. The most common data sources were registries (60.3%) followed by hospital data (31.7%). RWE was mainly included to support safety (87.3%) and efficacy (49.2%) with cohort studies being the most frequently used study design (88.9%). For EOIs, 28 of 153 products (18.3%) contained RWE with a total of 36 studies. For 57.1% of these products, studies were conducted prior to the EOIs. RWE sources were mainly registries (35.6%) and hospital data (27.0%). RWE was typically used to support safety (82.1%) and efficacy (53.6%). Cohort studies were the most commonly used study design (87.6%). We conclude that there is widespread use of RWE to support evaluation of MAAs and EOIs submitted to the EMA and identify areas where further research is required.

Pessary or surgery for a symptomatic pelvic organ prolapse: the PEOPLE study, a multicentre prospective cohort study

OBJECTIVE

To compare the 24-month efficacy of pessary or surgery as the primary treatment for symptomatic pelvic organ prolapse (POP).

DESIGN

Multicentre prospective comparative cohort study.

SETTING

Twenty-two Dutch hospitals.

POPULATION

Women referred with symptomatic POP of stage ≥2 and moderate-to-severe POP symptoms.

METHODS

The primary outcome was subjective improvement at the 24-month follow-up according to the Patient Global Impression of Improvement (PGI-I) scale. Secondary outcomes included improvement in prolapse-related symptoms measured with the Pelvic Floor Distress Inventory (PFDI-20), improvement in subjective severeness of symptoms according to the Patient Global Impression of Severity (PGI-S) scale and crossover between therapies. The primary safety outcome was the occurrence of adverse events.

MAIN OUTCOME MEASURE

PGI-I at 24 months.

RESULTS

We included 539 women, with 335 women (62.2%) in the pessary arm and 204 women (37.8%) in the surgery arm. After 24 months, subjective improvement was reported by 134 women (83.8%) in the surgery group compared with 180 women (74.4%) in the pessary group (risk difference 9.4%, 95% CI 1.4-17.3%, P < 0.01). Seventy-nine women (23.6%) switched from pessary to surgery and 22 women (10.8%) in the surgery group underwent additional treatment. Both groups showed a significant reduction in bothersome POP symptoms (P ≤ 0.01) and a reduction in the perceived severity of symptoms (P ≤ 0.001) compared with the baseline.

CONCLUSIONS

Significantly more women in the surgery group reported a subjective improvement after 24 months. Both therapies, however, showed a clinically significant improvement of prolapse symptoms.

TWEETABLE ABSTRACT

Pessary treatment and vaginal surgery are both efficacious in reducing the presence and severity of prolapse symptoms, although the chance of significant improvement is higher following surgery.

The CErebro Placental RAtio as indicator for delivery following perception of reduced fetal movements, protocol for an international cluster randomised clinical trial; the CEPRA study

Background

Routine assessment in (near) term pregnancy is often inaccurate for the identification of fetuses who are mild to moderately compromised due to placental insufficiency and are at risk of adverse outcomes, especially when fetal size is seemingly within normal range for gestational age. Although biometric measurements and cardiotocography are frequently used, it is known that these techniques have low sensitivity and specificity. In clinical practice this diagnostic uncertainty results in considerable ‘over treatment’ of women with healthy fetuses whilst truly compromised fetuses remain unidentified. The CPR is the ratio of the umbilical artery pulsatility index over the middle cerebral artery pulsatility index. A low CPR reflects fetal redistribution and is thought to be indicative of placental insufficiency independent of actual fetal size, and a marker of adverse outcomes. Its utility as an indicator for delivery in women with reduced fetal movements (RFM) is unknown. The aim of this study is to assess whether expedited delivery of women with RFM identified as high risk on the basis of a low CPR improves neonatal outcomes. Secondary aims include childhood outcomes, maternal obstetric outcomes, and the predictive value of biomarkers for adverse outcomes.

Methods

International multicentre cluster randomised trial of women with singleton pregnancies with RFM at term, randomised to either an open or concealed arm. Only women with an estimated fetal weight ≥ 10th centile, a fetus in cephalic presentation and normal cardiotocograph are eligible and after informed consent the CPR will be measured. Expedited delivery is recommended in women with a low CPR in the open arm. Women in the concealed arm will not have their CPR results revealed and will receive routine clinical care. The intended sample size based on the primary outcome is 2160 patients. The primary outcome is a composite of: stillbirth, neonatal mortality, Apgar score < 7 at 5 min, cord pH < 7.10, emergency delivery for fetal distress, and severe neonatal morbidity.

Discussion

The CEPRA trial will identify whether the CPR is a good indicator for delivery in women with perceived reduced fetal movements.

Trial registration

Dutch trial registry (NTR), trial NL7557. Registered 25 February 2019.

Predictive factors for failure of the levonorgestrel releasing intrauterine system in women with heavy menstrual bleeding

Background

This study was conducted to identify factors that are associated with failure of treatment using the levonorgestrel releasing intrauterine system (LNG-IUS) in women with heavy menstrual bleeding.

Methods

For this study, data of a cohort of women treated with an LNG-IUS was used. Women who suffered from heavy menstrual bleeding, aged 34 years and older, without intracavitary pathology and without a future child wish, were recruited in hospitals and general practices in the Netherlands. Eight potential prognostic baseline variables (age, body mass index, caesarean section, vaginal delivery, previous treatment, anticoagulant use, dysmenorrhea, and pictorial blood assessment score) were analyzed using univariable and multivariable regression models to estimate the risk of failure. The main outcome measure was discontinuation of the LNG-IUS within 24 months of follow up, defined as removal of the LNG-IUS or receiving an additional intervention.

Results

A total of 209 women received the LNG-IUS, 201 women were included in the analyses. 93 women (46%) discontinued LNG-IUS treatment within 24 months. Multivariable analysis showed younger age (age below 45) (adjusted RR 1.51, 95% CI 1.10–2.09, p = .012) and severe dysmenorrhea (adjusted RR 1.36, 95% CI 1.01–1.82, p = .041) to be associated with a higher risk of discontinuation.

Conclusions

High discontinuation rates are found in women who receive an LNG-IUS to treat heavy menstrual bleeding. A younger age and severe dysmenorrhea are found to be risk factors for discontinuation of LNG-IUS treatment. These results are relevant for counselling women with heavy menstrual bleeding.

Treatment of women with heavy menstrual bleeding: Results of a prospective cohort study alongside a randomised controlled trial

OBJECTIVE

The objective of this study was to compare the reintervention rate of women who opted for treatment with the levonorgestrel-releasing intrauterine system (LNG-IUS) to women who opted for endometrial ablation. Furthermore, the difference in reintervention rate between women in this observational cohort and women who were randomised was compared, with the hypothesis that women who actively decide on treatment have lower reintervention rates compared to women in a RCT.

STUDY DESIGN

An observational cohort study alongside a multicentre randomised controlled trial (RCT) was conducted between April 2012 and January 2016, with a follow-up time of 24 months, in 26 hospitals and nearby general practices in the Netherlands. Women suffering from heavy menstrual bleeding, aged 34 years and older, without intracavitary pathology and without a future fertility desire, were eligible for this trial. Women who declined randomisation were asked to participate in the observational cohort. The outcome measure was reintervention rate at 24 months of follow-up.

RESULTS

276 women were followed in the observational cohort of which 87 women preferred an initial treatment with LNG-IUS and 189 women preferred an initial treatment with endometrial ablation. At 24 months of follow-up women in the LNG-IUS-group were more likely to receive a reintervention compared to the women in the ablation group, 28/81 (35 %) versus 25/178 (14 %) (aRR 2.42, CI 1.47-3.98, p-value 0.001). No differences in reintervention rates were found between women in the observational cohort and women in the RCT.

CONCLUSIONS

Women who receive an LNG-IUS are more likely to undergo an additional intervention compared to women who receive endometrial ablation. Reintervention rates of women in the cohort and RCT population were comparable. The results of this study endorse the findings of the RCT and will contribute to shared decision making in women with heavy menstrual bleeding.

Induction of labour at 41 weeks or expectant management until 42 weeks: A systematic review and an individual participant data meta-analysis of randomised trials

BACKGROUND

The risk of perinatal death and severe neonatal morbidity increases gradually after 41 weeks of pregnancy. Several randomised controlled trials (RCTs) have assessed if induction of labour (IOL) in uncomplicated pregnancies at 41 weeks will improve perinatal outcomes. We performed an individual participant data meta-analysis (IPD-MA) on this subject.

METHODS AND FINDINGS

We searched PubMed, Excerpta Medica dataBASE (Embase), The Cochrane Library, Cumulative Index of Nursing and Allied Health Literature (CINAHL), and PsycINFO on February 21, 2020 for RCTs comparing IOL at 41 weeks with expectant management until 42 weeks in women with uncomplicated pregnancies. Individual participant data (IPD) were sought from eligible RCTs. Primary outcome was a composite of severe adverse perinatal outcomes: mortality and severe neonatal morbidity. Additional outcomes included neonatal admission, mode of delivery, perineal lacerations, and postpartum haemorrhage. Prespecified subgroup analyses were conducted for parity (nulliparous/multiparous), maternal age (<35/≥35 years), and body mass index (BMI) (<30/≥30). Aggregate data meta-analysis (MA) was performed to include data from RCTs for which IPD was not available. From 89 full-text articles, we identified three eligible RCTs (n = 5,161), and two contributed with IPD (n = 4,561). Baseline characteristics were similar between the groups regarding age, parity, BMI, and higher level of education. IOL resulted overall in a decrease of severe adverse perinatal outcome (0.4% [10/2,281] versus 1.0% [23/2,280]; relative risk [RR] 0.43 [95% confidence interval [CI] 0.21 to 0.91], p-value 0.027, risk difference [RD] -57/10,000 [95% CI -106/10,000 to -8/10,000], I2 0%). The number needed to treat (NNT) was 175 (95% CI 94 to 1,267). Perinatal deaths occurred in one (<0.1%) versus eight (0.4%) pregnancies (Peto odds ratio [OR] 0.21 [95% CI 0.06 to 0.78], p-value 0.019, RD -31/10,000, [95% CI -56/10,000 to -5/10,000], I2 0%, NNT 326, [95% CI 177 to 2,014]) and admission to a neonatal care unit ≥4 days occurred in 1.1% (24/2,280) versus 1.9% (46/2,273), (RR 0.52 [95% CI 0.32 to 0.85], p-value 0.009, RD -97/10,000 [95% CI -169/10,000 to -26/10,000], I2 0%, NNT 103 [95% CI 59 to 385]). There was no difference in the rate of cesarean delivery (10.5% versus 10.7%; RR 0.98, [95% CI 0.83 to 1.16], p-value 0.81) nor in other important perinatal, delivery, and maternal outcomes. MA on aggregate data showed similar results. Prespecified subgroup analyses for the primary outcome showed a significant difference in the treatment effect (p = 0.01 for interaction) for parity, but not for maternal age or BMI. The risk of severe adverse perinatal outcome was decreased for nulliparous women in the IOL group (0.3% [4/1,219] versus 1.6% [20/1,264]; RR 0.20 [95% CI 0.07 to 0.60], p-value 0.004, RD -127/10,000, [95% CI -204/10,000 to -50/10,000], I2 0%, NNT 79 [95% CI 49 to 201]) but not for multiparous women (0.6% [6/1,219] versus 0.3% [3/1,264]; RR 1.59 [95% CI 0.15 to 17.30], p-value 0.35, RD 27/10,000, [95% CI -29/10,000 to 84/10,000], I2 55%). A limitation of this IPD-MA was the risk of overestimation of the effect on perinatal mortality due to early stopping of the largest included trial for safety reasons after the advice of the Data and Safety Monitoring Board. Furthermore, only two RCTs were eligible for the IPD-MA; thus, the possibility to assess severe adverse neonatal outcomes with few events was limited.

CONCLUSIONS

In this study, we found that, overall, IOL at 41 weeks improved perinatal outcome compared with expectant management until 42 weeks without increasing the cesarean delivery rate. This benefit is shown only in nulliparous women, whereas for multiparous women, the incidence of mortality and morbidity was too low to demonstrate any effect. The magnitude of risk reduction of perinatal mortality remains uncertain. Women with pregnancies approaching 41 weeks should be informed on the risk differences according to parity so that they are able to make an informed choice for IOL at 41 weeks or expectant management until 42 weeks. Study Registration: PROSPERO CRD42020163174.

Effect of single- versus double-layer uterine closure during caesarean section on postmenstrual spotting (2Close): multicentre, double-blind, randomised controlled superiority trial

OBJECTIVE

To evaluate whether double-layer uterine closure after a first caesarean section (CS) is superior compared with single-layer uterine closure in terms of postmenstrual spotting and niche development in the uterine caesarean scar.

DESIGN

Multicentre, double-blind, randomised controlled superiority trial.

SETTING

Thirty-two hospitals in the Netherlands.

POPULATION

A total of 2292 women aged ≥18 years undergoing a first CS were randomly assigned to each procedure (1:1): 1144 women were assigned to single-layer uterine closure and 1148 women were assigned to double-layer uterine closure.

METHODS

Single-layer unlocked closure and double-layer unlocked closure, with the second layer imbricating the first.

MAIN OUTCOME MEASURES

Number of days with postmenstrual spotting during one menstrual cycle 9 months after CS.

SECONDARY OUTCOMES

perioperative and menstrual characteristics; transvaginal ultrasound measurements.

RESULTS

A total of 774 (67.7%) women from the single-layer group and 770 (67.1%) women from the double-layer group were evaluable for the primary outcome, as a result of drop-out and amenorrhoea. The mean number of postmenstrual spotting days was 1.33 (bootstrapped 95% CI 1.12-1.54) after single-layer closure and 1.26 (bootstrapped 95% CI 1.07-1.45) after double-layer closure (adjusted mean difference -0.07, 95% CI -0.37 to 0.22, P = 0.810). The operative time was 3.9 minutes longer (95% CI 3.0-4.9 minutes, P < 0.001) and niche prevalence was 4.7% higher (95% CI 0.7-8.7%, P = 0.022) after double-layer closure.

CONCLUSIONS

The superiority of double-layer closure compared with single-layer closure in terms of postmenstrual spotting after a first CS was not shown. Long-term obstetric follow-up of our trial is needed to assess whether uterine caesarean closure guidelines should be adapted.

TWEETABLE ABSTRACT

Double-layer uterine closure is not superior for postmenstrual spotting after a first caesarean; single-layer closure performs slightly better on other outcomes.

Temporizing management vs immediate delivery in early-onset severe preeclampsia between 28 and 34 weeks of gestation (TOTEM study): An open-label randomized controlled trial

Introduction

There is little evidence to guide the timing of delivery of women with early‐onset severe preeclampsia. We hypothesize that immediate delivery is not inferior for neonatal outcome but reduces maternal complications compared with temporizing management.

Material and methods

This Dutch multicenter open‐label randomized clinical trial investigated non‐inferiority for neonatal outcome of temporizing management as compared with immediate delivery (TOTEM NTR 2986) in women between 27⁺⁵ and 33⁺⁵ weeks of gestation admitted for early‐onset severe preeclampsia with or without HELLP syndrome. In participants allocated to receive immediate delivery, either induction of labor or cesarean section was initiated at least 48 hours after admission. Primary outcomes were adverse perinatal outcome, defined as a composite of severe respiratory distress syndrome, bronchopulmonary dysplasia, culture proven sepsis, intraventricular hemorrhage grade 3 or worse, periventricular leukomalacia grade 2 or worse, necrotizing enterocolitis stage 2 or worse, and perinatal death. Major maternal complications were secondary outcomes. It was estimated 1130 women needed to be enrolled. Analysis was by intention‐to‐treat.

Results

The trial was halted after 35 months because of slow recruitment. Between February 2011 and December 2013, a total of 56 women were randomized to immediate delivery (n = 26) or temporizing management (n = 30). Median gestational age at randomization was 30 weeks. Median prolongation of pregnancy was 2 days (interquartile range 1‐3 days) in the temporizing management group. Mean birthweight was 1435 g after immediate delivery vs 1294 g after temporizing management (P = .14). The adverse perinatal outcome rate was 55% in the immediate delivery group vs 52% in the temporizing management group (relative risk 1.06; 95% confidence interval 0.67‐1.70). In both groups there was one neonatal death and no maternal deaths. In the temporizing treatment group, one woman experienced pulmonary edema and one placental abruption. Analyses of only the singleton pregnancies did not result in other outcomes.

Conclusions

Early termination of the trial precluded any conclusions for the main outcomes. We observed that temporizing management resulted in a modest prolongation of pregnancy without changes in perinatal and maternal outcome. Conducting a randomized study for this important research question did not prove feasible.

Adjuvant VACcination against HPV in surgical treatment of Cervical Intra-epithelial Neoplasia (VACCIN study) a study protocol for a randomised controlled trial

BACKGROUND

Cervical cancer is caused by Human Papilloma viruses (HPV) and is preceded by precursor stages: Cervical Intraepithelial Neoplasia (CIN). CIN is mostly found in women in their reproductive age and treated with a Loop Electrosurgical Excision Procedure (LEEP). The recurrence or residual disease rate after treatment is up to 17%. These women have a lifelong increased risk of recurrent CIN, cervical cancer and other HPV related malignancies. Furthermore, LEEP treatments are associated with complications such as premature birth. Limited data show that prophylactic HPV vaccination at the time of LEEP reduces recurrence rates, therefore leading to a reduction in repeated surgical interventions and side effect like preterm birth. The primary study objective is to evaluate the efficacy of the nonavalent HPV vaccination in women with a CIN II-III (high-grade squamous intraepithelial lesion (HSIL) lesion who will undergo a LEEP in preventing recurrent CIN II-III after 24 months.

METHODS

This study is a randomised, double blinded, placebo controlled trial in 750 patients without prior HPV vaccination or prior treatment for CIN and with histologically proven CIN II-III (independent of their hrHPV status) for whom a LEEP is planned. Included patients will be randomised to receive either three injections with nonavalent (9 HPV types) HPV vaccine or placebo injections (NaCL 0.9%) as a comparator. Treatment and follow-up will be according the current Dutch guidelines. Primary outcome is recurrence of a CIN II or CIN III lesion at 24 months. A normal PAP smear with negative hrHPV test serves as surrogate for absence of CIN. At the start and throughout the study HPV typing, quality of life and cost effectiveness will be tested.

DISCUSSION

Although prophylactic HPV vaccines are highly effective, little is known about the effectivity of HPV vaccines on women with CIN. Multiple LEEP treatments are associated with complications. We would like to evaluate the efficacy of HPV vaccination in addition to LEEP treatment to prevent residual or recurrent cervical dysplasia and decrease risks of repeated surgical treatment.

TRIAL REGISTRATION

Medical Ethical Committee approval number: NL66775.078.18. Affiliation: Erasmus Medical Centre. Dutch trial register: NL 7938. Date of registration 2019-08-05.

Maternal Sildenafil vs Placebo in Pregnant Women With Severe Early-Onset Fetal Growth Restriction: A Randomized Clinical Trial

IMPORTANCE

Severe early onset fetal growth restriction caused by placental dysfunction leads to high rates of perinatal mortality and neonatal morbidity. The phosphodiesterase 5 inhibitor, sildenafil, inhibits cyclic guanosine monophosphate hydrolysis, thereby activating the effects of nitric oxide, and might improve uteroplacental function and subsequent perinatal outcomes.

OBJECTIVE

To determine whether sildenafil reduces perinatal mortality or major morbidity.

DESIGN, SETTING, AND PARTICIPANTS

This placebo-controlled randomized clinical trial was conducted at 10 tertiary referral centers and 1 general hospital in the Netherlands from January 20, 2015, to July 16, 2018. Participants included pregnant women between 20 and 30 weeks of gestation with severe fetal growth restriction, defined as fetal abdominal circumference below the third percentile or estimated fetal weight below the fifth percentile combined with Dopplers measurements outside reference ranges or a maternal hypertensive disorder. The trial was stopped early owing to safety concerns on July 19, 2018, whereas benefit on the primary outcome was unlikely. Data were analyzed from January 20, 2015, to January 18, 2019. The prespecified primary analysis was an intention-to-treat analysis including all randomized participants.

INTERVENTIONS

Participants were randomized to sildenafil, 25 mg, 3 times a day vs placebo.

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite of perinatal mortality or major neonatal morbidity until hospital discharge.

RESULTS

Out of 360 planned participants, a total of 216 pregnant women were included, with 108 women randomized to sildenafil (median gestational age at randomization, 24 weeks 5 days [interquartile range, 23 weeks 3 days to 25 weeks 5 days]; mean [SD] estimated fetal weight, 458 [160] g) and 108 women randomized to placebo (median gestational age, 25 weeks 0 days [interquartile range, 22 weeks 5 days to 26 weeks 3 days]; mean [SD] estimated fetal weight, 464 [186] g). In July 2018, the trial was halted owing to concerns that sildenafil may cause neonatal pulmonary hypertension, whereas benefit on the primary outcome was unlikely. The primary outcome, perinatal mortality or major neonatal morbidity, occurred in the offspring of 65 participants (60.2%) allocated to sildenafil vs 58 participants (54.2%) allocated to placebo (relative risk, 1.11; 95% CI, 0.88-1.40; P = .38). Pulmonary hypertension, a predefined outcome important for monitoring safety, occurred in 16 neonates (18.8%) in the sildenafil group vs 4 neonates (5.1%) in the placebo group (relative risk, 3.67; 95% CI, 1.28-10.51; P = .008).

CONCLUSIONS AND RELEVANCE

These findings suggest that antenatal maternal sildenafil administration for severe early onset fetal growth restriction did not reduce the risk of perinatal mortality or major neonatal morbidity. The results suggest that sildenafil may increase the risk of neonatal pulmonary hypertension.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02277132.

Child outcomes after amnioinfusion compared with no intervention in women with second-trimester rupture of membranes: a long-term follow-up study of the PROMEXIL-III trial

OBJECTIVE

To assess the effect of transabdominal amnioinfusion or no intervention on long-term outcomes in children born after second-trimester prelabour rupture of the membranes (PROM between 16^+0/7 -24^+0/7  weeks) and oligohydramnios.

POPULATION

Follow up of infants of women who participated in the randomised controlled trial: PPROMEXIL-III (NTR3492).

METHODS

Surviving infants were invited for neurodevelopmental assessment up to 5 years of corrected age using a Bayley Scales of Infant and Toddler Development or a Wechsler Preschool and Primary Scale of Intelligence. Parents were asked to complete several questionnaires.

MAIN OUTCOME MEASURES

Neurodevelopmental outcomes were measured. Mild delay was defined as -1 standard deviation (SD), severe delay as -2 SD. Healthy long-term survival was defined as survival without neurodevelopmental delay or respiratory problems.

RESULTS

In the amnioinfusion group, 18/28 children (64%) died versus 21/28 (75%) in the no intervention group (relative risk 0.86; 95% confidence interval [CI] 0.60-1.22). Follow-up data were obtained from 14/17 (82%) children (10 amnioinfusion, 4 no intervention). In both groups, 2/28 (7.1%) had a mild neurodevelopmental delay. No severe delay was seen. Healthy long-term survival occurred in 5/28 children (17.9%) after amnioinfusion versus 2/28 (7.1%) after no intervention (odds ratio 2.50; 95% CI 0.53-11.83). When analysing data for all assessed survivors, 10/14 (71.4%) survived without mild neurodevelopmental delay and 7/14 (50%) were classified healthy long-term survivor.

CONCLUSIONS

In this small sample of women suffering second-trimester PROM and oligohydramnios, amnioinfusion did not improve long-term outcomes. Overall, 71% of survivors had no neurodevelopmental delay.

TWEETABLE ABSTRACT

Healthy long-term survival was comparable for children born after second-trimester PROM and treatment with amnioinfusion or no intervention.

Cognitive outcome in congenital central hypothyroidism: a systematic review with meta-analysis of individual patient data

OBJECTIVE

To provide an overview of cognitive and motor outcome, and quality of life (QoL) in patients with congenital central hypothyroidism (CH-C).

DESIGN

Systematic review with individual patient data (IPD) meta-analysis.

METHODS

OVID MEDLINE, EMBASE and PsycInfo were searched from inception to June 11th, 2019. Studies in patients with CH-C, either isolated or with multiple pituitary hormone deficiency (MPHD), were included if CH-C patients could be separated from any additional patient groups. Primary outcomes were full-scale intelligence quotient (FSIQ) and motor outcome; secondary outcome was QoL. Following data-extraction, one-stage IPD meta-analysis was performed, fitting a linear mixed model with FSIQ as dependent variable. Random intercepts were fitted for each study.

RESULTS

Six studies measuring FSIQ were eligible for meta-analysis, comprising 30 CH-C patients (20 males; 27 MPHD patients). FSIQ range was wide (64-123). Mean weighted FSIQ was 97 (95% CI: 88-105). Twenty-seven percent had an FSIQ below 85 (≥1 s.d. below norm score), and 10% below 70 (≥2 s.d. below norm score). There was no significant association between FSIQ and sex or age. Age at treatment initiation was available from three studies only, thus impeding a reliable analysis of this parameter. Motor outcome and QoL were each studied in one study; no quantitative analyses could be performed for these outcomes.

CONCLUSION

A wide range in FSIQ scores was observed in CH-C patients. Results should be interpreted with caution, because included patients mainly had MPHD and age at treatment initiation was unknown for the majority of patients.

Induction of labour at 41 weeks versus expectant management until 42 weeks (INDEX): multicentre, randomised non-inferiority trial

OBJECTIVE

To compare induction of labour at 41 weeks with expectant management until 42 weeks in low risk women.

DESIGN

Open label, randomised controlled non-inferiority trial.

SETTING

123 primary care midwifery practices and 45 hospitals (secondary care) in the Netherlands, 2012-16.

PARTICIPANTS

1801 low risk women with an uncomplicated singleton pregnancy: randomised to induction (n=900) or to expectant management until 42 weeks (n=901).

INTERVENTIONS

Induction at 41 weeks or expectant management until 42 weeks with induction if necessary.

PRIMARY OUTCOME MEASURES

Primary outcome was a composite of perinatal mortality and neonatal morbidity (Apgar score <7 at five minutes, arterial pH <7.05, meconium aspiration syndrome, plexus brachialis injury, intracranial haemorrhage, and admission to a neonatal intensive care unit (NICU). Secondary outcomes included maternal outcomes and mode of delivery. The null hypothesis that expectant management is inferior to induction was tested with a non-inferiority margin of 2%.

RESULTS

Median gestational age at delivery was 41 weeks+0 days (interquartile range 41 weeks+0 days-41 weeks+1 day) for the induction group and 41 weeks+2 days (41 weeks+0 days-41 weeks+5 days) for the expectant management group. The primary outcome was analysed for both the intention-to-treat population and the per protocol population. In the induction group, 15/900 (1.7%) women had an adverse perinatal outcome versus 28/901 (3.1%) in the expectant management group (absolute risk difference -1.4%, 95% confidence interval -2.9% to 0.0%, P=0.22 for non-inferiority). 11 (1.2%) infants in the induction group and 23 (2.6%) in the expectant management group had an Apgar score <7 at five minutes (relative risk (RR) 0.48, 95% CI 0.23 to 0.98). No infants in the induction group and three (0.3%) in the expectant management group had an Apgar score <4 at five minutes. One fetal death (0.1%) occurred in the induction group and two (0.2%) in the expectant management group. No neonatal deaths occurred. 3 (0.3%) neonates in the induction group versus 8 (0.9%) in the expectant management group were admitted to an NICU (RR 0.38, 95% CI 0.10 to 1.41). No significant difference was found in composite adverse maternal outcomes (induction n=122 (13.6%) v expectant management n=102 (11.3%)) or in caesarean section rate (both groups n=97 (10.8%)).

CONCLUSIONS

This study could not show non-inferiority of expectant management compared with induction of labour in women with uncomplicated pregnancies at 41 weeks; instead a significant difference of 1.4% was found for risk of adverse perinatal outcomes in favour of induction, although the chances of a good perinatal outcome were high with both strategies and the incidence of perinatal mortality, Apgar score <4 at five minutes, and NICU admission low.

TRIAL REGISTRATION

Netherlands Trial Register NTR3431.

Long-term use of 5α-reductase inhibitors and the risk of male breast cancer

BACKGROUND

The 5α-reductase inhibitors (5-ARI) finasteride and dutasteride are indicated for the treatment of lower urinary tract symptoms caused by benign prostatic hyperplasia. Case reports have suggested that 5-ARIs increase the risk for male breast cancer, with no conclusive evidence. The objective of this study was to quantify the association between use of 5-ARIs and the risk for male breast cancer.

METHODS

A case-control study was conducted with data from the United Kingdom Clinical Practice Research Datalink database among all men aged 45 years and older in the period 1 January 1992 to 31 December 2011. Cases of men diagnosed with breast cancer were matched to up 10 controls on age and general practice. Crude and adjusted odds ratios were estimated for the risk of breast cancer associated with the use of 5-ARIs.

RESULTS

Three hundred and ninety-eight cases were identified and matched to 3,930 controls. Ever use of 5-ARIs was associated with an adjusted odds ratio for breast cancer of 1.08 (95 % CI 0.62-1.87) compared to non-users. Increasing cumulative duration of treatment showed no increasing risks: adjusted odds ratios for use for less than 280, for 280 to 1,036 and for more than 1,036 days were 1.21 (95 % CI 0.47-3.10), 0.94 (95 % CI 0.36-2.41) and 1.29 (95 % CI 0.54-3.08), respectively.

CONCLUSIONS

In this study, there was no evidence of an association between short- or long-term treatment with 5-ARIs and the risk for breast cancer in older men.

Number of patients studied prior to approval of new medicines: a database analysis

BACKGROUND

At the time of approval of a new medicine, there are few long-term data on the medicine's benefit-risk balance. Clinical trials are designed to demonstrate efficacy, but have major limitations with regard to safety in terms of patient exposure and length of follow-up. This study of the number of patients who had been administered medicines at the time of medicine approval by the European Medicines Agency aimed to determine the total number of patients studied, as well as the number of patients studied long term for chronic medication use, compared with the International Conference on Harmonisation's E1 guideline recommendations.

METHODS AND FINDINGS

All medicines containing new molecular entities approved between 2000 and 2010 were included in the study, including orphan medicines as a separate category. The total number of patients studied before approval was extracted (main outcome). In addition, the number of patients with long-term use (6 or 12 mo) was determined for chronic medication. 200 unique new medicines were identified: 161 standard and 39 orphan medicines. The median total number of patients studied before approval was 1,708 (interquartile range [IQR] 968-3,195) for standard medicines and 438 (IQR 132-915) for orphan medicines. On average, chronic medication was studied in a larger number of patients (median 2,338, IQR 1,462-4,135) than medication for intermediate (878, IQR 513-1,559) or short-term use (1,315, IQR 609-2,420). Safety and efficacy of chronic use was studied in fewer than 1,000 patients for at least 6 and 12 mo in 46.4% and 58.3% of new medicines, respectively. Among the 84 medicines intended for chronic use, 68 (82.1%) met the guideline recommendations for 6-mo use (at least 300 participants studied for 6 mo and at least 1,000 participants studied for any length of time), whereas 67 (79.8%) of the medicines met the criteria for 12-mo patient exposure (at least 100 participants studied for 12 mo).

CONCLUSIONS

For medicines intended for chronic use, the number of patients studied before marketing is insufficient to evaluate safety and long-term efficacy. Both safety and efficacy require continued study after approval. New epidemiologic tools and legislative actions necessitate a review of the requirements for the number of patients studied prior to approval, particularly for chronic use, and adequate use of post-marketing studies. Please see later in the article for the Editors' Summary.

Potential misinterpretation of treatment effects due to use of odds ratios and logistic regression in randomized controlled trials

BACKGROUND

In randomized controlled trials (RCTs), the odds ratio (OR) can substantially overestimate the risk ratio (RR) if the incidence of the outcome is over 10%. This study determined the frequency of use of ORs, the frequency of overestimation of the OR as compared with its accompanying RR in published RCTs, and we assessed how often regression models that calculate RRs were used.

METHODS

We included 288 RCTs published in 2008 in five major general medical journals (Annals of Internal Medicine, British Medical Journal, Journal of the American Medical Association, Lancet, New England Journal of Medicine). If an OR was reported, we calculated the corresponding RR, and we calculated the percentage of overestimation by using the formula .

RESULTS

Of 193 RCTs with a dichotomous primary outcome, 24 (12.4%) presented a crude and/or adjusted OR for the primary outcome. In five RCTs (2.6%), the OR differed more than 100% from its accompanying RR on the log scale. Forty-one of all included RCTs (n = 288; 14.2%) presented ORs for other outcomes, or for subgroup analyses. Nineteen of these RCTs (6.6%) had at least one OR that deviated more than 100% from its accompanying RR on the log scale. Of 53 RCTs that adjusted for baseline variables, 15 used logistic regression. Alternative methods to estimate RRs were only used in four RCTs.

CONCLUSION

ORs and logistic regression are often used in RCTs and in many articles the OR did not approximate the RR. Although the authors did not explicitly misinterpret these ORs as RRs, misinterpretation by readers can seriously affect treatment decisions and policy making.