National Retrospective Cohort Study Research Articles

Out-of-hospital cardiac arrest in Bahrain: National retrospective cohort study

AimThere is limited research on Out-of-hospital cardiac arrest (OHCA) in the Gulf Cooperation Council (GCC) and especially in Bahrain. This is the first study to describe the incidence, characteristics, and outcomes of OHCA in Bahrain. MethodsThis was a retrospective national observational study on OHCA patients in Bahrain using the Utstein framework for resuscitation. Data was collected between 1st July 2022 to 30th June 2023 from the electronic medical records of the only three governmental hospitals emergency departments (EDs) and National Ambulance (NA). ResultsThe annual incidence of OHCA attended by (Emergency Medical Services) EMS was nearly 21 per 100,000 population. The majority were males (n = 228, 68.8 %) with median age of 65 years (IQR=49–78). Most OHCA cases were witnessed (n = 265, 81 %), with (n = 247, 76 %) happened at home/residence. Rates for bystander CPR was low (n = 122, 36.8 %) and bystander automated external defibrillator (AED) was not performed in any of the cases. The OHCA cases transported by the NA was (n = 314, 94.8 %), with median response time of 9 min (IQR=7–12). However, only (n = 20, 6.0 %) were witnessed by EMS, and (n = 7, 2.1 %) received EMS defibrillation for shockable rhythms. First monitored rhythms included shockable rhythm in (n = 28, 8.5 %) versus non-shockable rhythm in (n = 303, 91.5 %). In the EDs, return of spontaneous circulation was achieved in (n = 60, 18.1 %) cases. But survival rate to hospital discharge at 30-day was (n = 4, 1.2 %) and survival rate to hospital discharge with good neurological outcomes was (n = 0, 0 %). Conclusion: In Bahrain the estimated annual incidence of OHCA is 21 individuals per 100,000 population, with a very low survival rate. Solutions should focus on community-level CPR and AED training, evaluating OHCA care provided by EMS, and establishing OHCA registry.

Heightened migraine risk in patients with rheumatoid arthritis: A national retrospective cohort study.

This study aimed to evaluate the association between rheumatoid arthritis (RA) and subsequent migraine risk using the Korean National Health Insurance Service database. Migraine may be related to immune dysfunction and previous studies have suggested an association with chronic inflammatory rheumatic diseases; however, the relationship between RA and migraine remains unclear. This was a population-based, nationwide, retrospective, longitudinal cohort study. Participants were enrolled from 2010 to 2017 and followed up until 2019. A total of 42,674 patients who had undergone a health checkup within 2 years prior to the initial diagnosis of RA were included in the study, after applying the exclusion criteria (previous migraine, other rheumatic disease, missing variables of interest). A non-RA control was obtained by age and sex-matching (1:5). Finally, 42,644 patients with RA were enrolled, with 213,370 individuals without RA included as controls. Among the patients with RA, 29,744 had seropositive RA (SPRA), and 12,900 had seronegative RA (SNRA). SPRA was defined by the International Classification of Diseases 10th revision (ICD-10) code M05, prescription of disease-modifying anti-rheumatic drugs (DMARDs), and enrollment in a special copayment reduction program. SNRA was defined by the ICD-10 code M06 and prescription of any DMARD. The primary endpoint was the occurrence of migraine incidents, defined using the ICD-10 code of migraine (G43). A total of 22,294 migraine cases (17,912/213,370 [8.3%] in controls and 4382/42,674 [10.2%] in RA) were reported during a mean follow-up of 4.4 years after a 1-year lag period. Patients with RA had a 1.2-fold higher risk of migraine compared with controls (adjusted hazard ratio [aHR] 1.21, 95% confidence interval [CI] 1.17-1.26). Increased risk of migraine was found in both patients with SNRA and SPRA compared with controls (aHR 1.20, CI 1.15-1.24 in SPRA; aHR 1.26, CI 1.19-1.34 in SNRA). Compared to patients with SNRA, those with SPRA did not demonstrate a heightened risk (aHR 0.94, CI 0.88-1.01). A significant interaction was confirmed between covariates (male, current smoker, those with diabetes mellitus, and dyslipidemia) and the risk of migraine (p for interaction of <0.05). RA was linked to a higher migraine risk, regardless of seropositivity.

Psychiatric disorders and comorbidity in women with Turner Syndrome: a retrospective national cohort study

Turner syndrome (TS) is a genetic condition characterized by partial or complete monosomy X. A reduced life expectancy has been shown in TS, depending on an increased risk of aortic dissection, and ischemic heart disease. Studies covering the occurrence of psychiatric conditions are sparse within TS. Several case reports describe concomitant TS and neuropsychiatric abnormalities that may represent a pathogenetic link to genetics, as well as feature correlates of TS. The aim of this study was to determine the presence, and the frequency of psychiatric diagnosis in women with TS in a Swedish cohort followed during 25 years’ time. Statistics from the entire female population in Sweden of corresponding age was used as reference. Data were retrieved from clinical examinations and validated from the National Board of Health and Welfare registries for women with TS (n = 487), aged 16 to 84 years, with respect to mental health disorders. The most common diagnoses in TS were mood and anxiety disorders. There was no increase in psychiatric diagnosis within the group with time, nor correlation to specific karyotype or somatic comorbidity as congenital heart disease and hypothyroidism, hormonal treatment, or childbirth. In addition, the frequency of psychiatric diagnosis in TS was lower than in the population-based data. Further investigations are needed in the view of the fact that women with Turner syndrome should not be burdened with more severe diagnoses.

Glucose-lowering medicines use before and after entry into long-term care facilities.

To examine changes in the use of glucose-lowering medicine (GLM) 12 months before and 12 months after long-term care facility (LTCF) entry among people with diabetes. A national retrospective cohort study was conducted using linked health and aged care data from the Registry of Senior Australians National Historical Cohort. Residents of LTCFs with diabetes aged 65 years or older from 2015 to 2019 were included. Prevalence of GLM use and the number of defined daily doses (DDDs) dispensed per 1000 resident-days were estimated quarterly (91-day) using Poisson regression models, or negative binomial regression when overdispersion was present. Among the 50 993 residents studied (median age 84 years), the prevalence of GLM use was 58.4% (95% confidence interval [CI] 58.0%-58.8%) in the 9-12 months pre-LTCF entry and 56.3% (95% CI 55.9%-56.8%) in the 9-12 months post-entry. The number of DDDs/1000 resident-days increased from 1015.2 (95% CI 1002.3-1028.1) to 1253.8 (95% CI 1168.4-1339.3) during the same period. GLM use in the 3 months pre-entry was 56.8% (95% CI 56.4%-57.2%) compared with 61.7% (95% CI 61.3%-62.1%) in the 3 months post-entry, with the increased use driven mainly by insulin. No marked changes in the number of GLMs dispensed or GLM type were observed at 9-12 months post-entry compared with 3 months pre-entry. Among 22 792 individuals dispensed a GLM in the 3 months prior to LTCF entry, 50.2% continued the same GLM at 9-12 months post-entry. GLM use peaked in the first 3 months following LTCF entry, driven mainly by insulin, hence, residents may benefit from close monitoring of diabetes treatment during this period.

501. CLINICAL APPLICATION OF OESOPHAGEAL CELL COLLECTION DEVICE AND BIOMARKER TESTING IN SYMPTOMATIC REFLUX DISEASE: A NATIONAL RETROSPECTIVE COHORT STUDY

Abstract Background Oesophageal cell collection device (OCCD) and biomarker testing was implemented nationally across Scotland in 2020 following the COVID-19 pandemic for symptomatic reflux patients referred to secondary care. Collected cells undergo biomarker testing for the presence of trefoil factor 3 (TFF3), an indicator of intestinal metaplasia (IM), in addition to atypia and p53. This national retrospective cohort study is the first to evaluate the clinical application of OCCD testing in symptomatic reflux patients and aims to assess whether OCCD and biomarker testing can safely be used as a triage tool for upper gastrointestinal (UGI) endoscopy in this cohort within secondary care. Methods Over a 32-month period, all patients undergoing OCCD testing with Cytosponge™ for investigation of reflux symptoms across 11 Scottish health boards were identified from prospectively maintained databases. In addition to OCCD testing, all patients also underwent clinical assessment either by UGI specialist nurses or consultants in secondary care. Individual patient records were interrogated to collect baseline demographics, OCCD test result and ongoing clinical management. Further analysis was performed on patients who subsequently underwent UGI endoscopy. All OCCD tests for Barrett’s surveillance were excluded from analysis. Results 1385 OCCD tests were performed for reflux symptoms in 1305 patients. 1103/1385 tests (79.6%) were TFF3 negative: 912/1305 (69.9%) patients discharged with no additional investigations. 355/1305 patients (27.2%) subsequently underwent UGI endoscopy. When insufficient tests with missing biomarker data were excluded, 50/314 patients (15.9%) had biopsies demonstrating IM: biomarkers were significantly more likely to be positive in this group (35.5% vs. 3.2%, p&amp;lt;0.001) (Table 1). 10/1103 patients with a TFF3 negative result (0.9%) had biopsies showing IM, dysplasia or malignancy. 1 patient had a TFF3 negative result but was diagnosed with oesophageal adenocarcinoma 27 months later. Conclusion OCCD and biomarker testing is effectively identifying those symptomatic reflux patients requiring further investigation with UGI endoscopy within the real-world setting. Biomarker testing is clearly aiding the diagnosis of Barrett’s oesophagus within this patient cohort. However, clinical assessment remains crucial to identify those with red flag symptoms and judicious follow-up of the discharged group will be critical to validate the ongoing use of OCCD testing in the long-term.

The Incidence of Cancers in Patients With Nonfunctional Adrenal Tumors: A Swedish Population-Based National Cohort Study.

It is unclear if nonfunctional adrenal tumors (NFAT) are associated with higher cancer incidence. To analyze the cancer incidence in patients with NFAT. In this national register-based retrospective cohort study, consecutive patients with NFAT identified in Sweden 2005-2019 and matched control individuals without adrenal tumors were followed up to 15 years. Outcome data were collected from national registers and adjusted for confounders. Both cases and controls were followed until newly diagnosed malignancy, death, or until 2019. Individuals with adrenal hormonal excess or prior malignancy were excluded. Among 17 726 cases, 10 777 (60.8%) were women, and the median age was 65 (IQR, 57-73) years. Among 124 366 controls, 69 514 (55.9%) were women, and the median age was 66 (IQR, 58-73) years. The incidence of any cancer was higher in patients with NFAT compared to controls (hazard ratio [HR] 1.35 95% CI 1.29-1.40; adjusted HR 1.31, 95% CI 1.26-1.37). NFAT was associated with a higher incidence of adrenal, thyroid, lung, stomach and small intestine, kidney, pancreatic, breast, and colorectal cancer. Sensitivity analyses did not change the overall results, but associations were not significantly increased after adjustment in patients with NFAT and appendicitis or gallbladder/biliary tract/pancreas disorders. Cancer incidence may have been underestimated by adjusting for unclear and benign tumors. The incidence of cancer was increased in patients with NFAT. Long-term follow-up may be indicated.

Recurrent Laryngeal Papillomatosis in Denmark from 1994 to 2021: A Nationwide Register Study.

The aim of this study is to describe the incidence and demographics of laryngeal papillomatosis (LP) in Denmark, including sex and age distribution, recurrence rates, and HPV subtypes, using a new method of register identification. The data were extracted from the Danish Pathology Data Bank using SNOMED codes instead of the usual method using ICD codes from the Danish National Health Register. The derived pathology records were manually verified by three medical doctors. The study period was 1994-2021. Patients were categorized according to age as either juvenile-onset RRP (JoRRP) if <18 years or adult-onset RRP (AoRRP) if 18 years or older. We identified 1819 RRP patients (JoRRP: 56; AoRRP:1763). The overall incidence per 100,000 inhabitants were 0.17 for JoRRP and 1.45 for AoRRP. The vast majority (72%) of the patients were male, but there was no significant difference in age at onset of RRP or recurrence rates between the sexes. Children below 3 years of age had the highest recurrence probability. Extracting data using SNOMED codes resulted in a positive predictive value of 99% regarding total number of biopsies and 98% regarding individuals. The incidence decreased throughout the study period. Comparable incidence and recurrence rates of RRP were found between Denmark and Norway. In this study, the Danish Pathology Register was found to be a highly valuable method for identifying LP patients. The effect of the nationwide HPV vaccination program can be evaluated using this method as the vaccinated cohort is starting to grow older and reproduce. Retrospective registry-based national cohort study, level of evidence 3 Laryngoscope, 2024.

Maternal ozone exposure lowers infant’s birthweight: A nationwide cohort of over 4 million livebirths in Iran

BackgroundNationwide evidence linking maternal ozone exposure with fetal growth restriction (FGR) was extensively scarce, especially in the Middle East with dry climate and distinct religious culture. MethodsWe carried out a national retrospective birth cohort study using registry-based records from 749 hospitals across 31 provinces in Iran from 2013 to 2018. Monthly concentrations of maximum daily average 8-hour (MDA8) ozone at 0.125° × 0.125° resolution were extracted from well-validated spatiotemporal grid dataset. Linear and logistic regression models were employed to evaluate associations of maternal MDA8 ozone exposure with birthweight outcomes. Assuming causality, the comparative risk assessment framework was utilized to estimate the burden of low birthweight (LBW), small for gestational age (SGA), and birthweight loss per livebirth (BLL) attributable to ambient ozone pollution. ResultsOf 4030383 livebirths included in the study, 264304 (6.6%) were LBW and 484405 (12.0%) were SGA. Each 10-ppb increase in MDA8 ozone exposure was associated with an odds ratio of 1.123 (95% confidence interval [CI]: 1.104 to 1.142) for LBW and 1.210 (95% CI: 1.197 to 1.223) for SGA, and a 30.5-g (95% CI: 29.0 to 32.0) reduction in birthweight. We observed approximately linear exposure-response relationships of maternal MDA8 ozone exposure with LBW (Pnonlinear= 0.786), SGA (Pnonlinear= 0.156), and birthweight reduction (Pnonlinear= 0.104). Under the premise of causal association, we estimated 6.6% (95% CI: 5.7 to 7.5) of LBW, 10.1% (95% CI: 9.6 to 10.6) of SGA, and 18.8 g (95% CI: 17.9 to 19.7) of BLL could be attributable to maternal ozone exposure in Iran. Considerably greater risk and burden of ozone-related FGR were observed among younger, less-educated, and rural-dwelling mothers. ConclusionsOur study provided compelling evidence that maternal ozone exposure was associated with heightened FGR risk and burden, particularly among socioeconomically disadvantaged mothers. These findings underscored the urgent need for government to incorporate socioeconomic factors into future ozone-related health policies, not only to mitigate pollution, but also minimize inequality.

Suicide in individuals with eating disorders who had sought mental health treatment in England: a national retrospective cohort study

Although studies have suggested a high risk of suicide in people with eating disorders, most studies have focused on suicidal ideation and attempts. There is little research on the characteristics of people with eating disorders who died by suicide, nor investigation of trends over time. We aimed to compare the characteristics of patients with eating disorders who died by suicide versus patients with other mental health diagnoses who died by suicide in England and to examine the trends in rates. In this national retrospective cohort study, data on all people (aged ≥10 years) who died by suicide in England, UK, between Jan 1, 1997, and Dec 31, 2021, while under the care (within the previous 12 months) of mental health services were obtained from the National Confidential Inquiry into Suicide and Safety in Mental Health (NCISH), in which clinical information is collected via a questionnaire completed by the mental health professional responsible for the patient's care. Incidence of suicide in, and demographic, clinical, and treatment characteristics of, patients with a diagnosis of eating disorder (as recorded by the treating clinician) who died by suicide were compared with patients with other mental health diagnoses who died by suicide within the same timeframe using univariable logistic regression analysis. People with related lived experience were involved in the study design, implementation, interpretation, and writing of the manuscript. Of 119 446 people for whom NCISH were notified of dying by suicide in England, 30 795 were under the recent care of mental health services, of whom 30 246 had known diagnoses and were included in analyses. Of these individuals, 10 373 (34%) were female and 19 873 (66%) were male; 2236 (8%) were of minority ethnicity; 382 (1%) had a diagnosis of eating disorder and 29 864 (99%) had another mental health diagnosis. Compared with patients with other mental health diagnoses who died by suicide, patients with eating disorders were younger (median age 33 years [range 15-90] vs 45 years [10-100]), more often female (343 [90%] female and 39 [10%] male in the eating disorders group; 10 030 [34%] female and 19 834 [66%] male in the other diagnoses group), and less likely to have evidence of conventional risk factors for suicide such as living alone (odds ratio [OR] 0·68, 95% CI 0·55-0·84). 22 (6%) of 382 were from a minority ethnic group. Patients with an eating disorder were characterised by a greater clinical complexity (eg, self-harm [OR 2·31, 95% CI 1·78-3·00], comorbidity [9·79, 6·81-14·1], and longer duration of illness [1·95, 1·56-2·43]), and were more likely to have died following overdoses (2·00, 1·62-2·45) than patients with other diagnoses. Childhood abuse (52 [37%] of 140) and domestic violence (18 [20%] of 91) were common in patients with eating disorders. Similar to patients with other diagnoses, most (244 [75%] of 326) of those with eating disorders who died by suicide were rated as low risk by clinicians at last contact. The number of suicide deaths in patients with eating disorders rose between 1997 and 2021 (incidence rate ratio [IRR] 1·03, 95% CI 1·02-1·05; p<0·0001), but rates fell when accounting for the greater number of patients entering mental health services (IRR 0·97, 0·95-1·00; p=0·033). This study was focused on people who sought help from mental health services. It did not consider subtypes of eating disorders or include a control group, but it does highlight possible areas for intervention. The comprehensive provision of evidence-based treatment for eating disorders and underlying conditions to address the clinical complexity in these patients might help to reduce suicide. Recognising limitations in clinical risk assessment, addressing early life experiences and current adversities, and appropriate prescribing might also be of benefit. Suicide prevention must remain a priority for eating disorder services and mental health care more widely. The Healthcare Quality Improvement Partnership.

The impact of COVID-19 on acute surgeries in England among the under-25s: a retrospective study of 61,360 appendicitis and 15,850 testicular torsion admissions

BackgroundLittle is known about how COVID-19 impacted acute surgical activity for children and young people (CYP) across England. Appendicitis and testicular torsion are common surgical conditions where treatment delays can lead to avoidable complications. We undertook a retrospective national cohort study. Primary aimTo describe monthly acute surgical activity in CYP during the pandemic. Secondary aimTo investigate evidence of delayed diagnosis and adverse outcomes, describing variations by age and deprivation. MethodsAcute admissions with appendicitis or testicular pain for under-18s were extracted using Hospital Episode Statistics. Interrupted time series modelling, Mann-Whitney and Pearson’s Chi-Squared tests compared the first 14 pandemic months with the previous five years. Results were stratified by age (0-4s, 5-9s and 10-17s) and appendicitis type (all, simple and complex). ResultsAdmissions for appendicitis and testicular torsion fell significantly early in the pandemic. The proportion of children with complex appendicitis also increased during this time. Orchidectomy rates rose in April 2020 for the 0-4s (+15.6% (7.9 to 23.3)) and 10-17s (+11.5% (4.9 to 18.2)), but when the pre-pandemic period was compared with the pandemic period as a whole, there were no overall statistically significant differences in orchidectomy rates between the study periods. Overall, there was a statistically significant rise in the orchidopexy rate during the pandemic period for the 10-17s when compared with the pre-pandemic period (Pre-pandemic: 17.0% vs Pandemic: 20.9%, p<0.0001). ConclusionA consistent reduction in activity, with short-lived periods of delayed presentations during pandemic peaks, occurred without persisting overall increased complication rates. These results provide useful national context for smaller sized studies that reported complications due to delays in surgery. Future research could examine how reduced activity impacted other healthcare settings and treatment pathways. Level of evidenceII

Surgical Management of Complex Ankle Fractures in Patients with Diabetes: A National Retrospective Multicentre Study.

Objectives: Patients with ankle fractures associated with diabetes experience more complications following standard open reduction-internal fixation (ORIF) than those without diabetes. Augmented fixation strategies, namely extended ORIF and hindfoot nails (HFNs), may offer better results and early weightbearing in this group. The aim of this study was to define the population of patients with diabetes undergoing primary fixation for ankle fractures. Secondarily, we aimed to assess the utilisation of standard and augmented strategies and the effect of these choices on surgical outcomes, including early post-operative weightbearing and surgical complications. Methods: A national multicentre retrospective cohort study was conducted between January and June 2019 in 56 centres (10 major trauma centres and 46 trauma units) in the United Kingdom; 1360 patients with specifically defined complex ankle fractures were enrolled. The patients' demographics, fixation choices and surgical and functional outcomes were recorded. Statistical analysis was performed to compare high-risk patients with and without diabetes. Results: There were 316 patients in the diabetes cohort with a mean age of 63.9 yrs (vs. 49.3 yrs. in the non-diabetes cohort), and a greater frailty score > 4 (24% vs. 14% (non-diabetes cohort) (p < 0.03)); 7.5% had documented neuropathy. In the diabetes cohort, 79.7% underwent standard ORIF, 7.1% extended ORIF and 10.2% an HFN, compared to 87.7%, 3.0% and 10.3% in the non-diabetes cohort. Surgical wound complications after standard-ORIF were higher in the diabetes cohort (15.1% vs. 8.7%) (p < 0.02), but patients with diabetes who underwent augmented techniques showed little difference in surgical outcomes/complications compared to non-diabetes patients, even though early-weightbearing rates were greater than for standard-ORIF. Conclusions: Ankle fractures in diabetes occur in older, frailer patients, whilst lower-than-expected neuropathy rates suggest a need for improved assessment. Augmented surgical techniques may allow earlier weightbearing without increasing complications, in keeping with modern guidelines in ankle fracture management.

P-745 effectiveness and safety of consecutive single embryo transfer compared to double embryo transfer: results from UK HFEA registry

Abstract Study question How does two-consecutive single embryo transfer (2xSET) affect reproductive outcomes of in-vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) compared to double embryo transfer (DET)? Summary answer 2xSET may provide greater or comparable live birth rates with lower multiple birth, preterm birth, and pregnancy loss or neonatal death rates compared to DET. What is known already Elective single embryo transfer (SET) in IVF/ICSI is widely encouraged over DET to minimise the risk of multiple birth and associated morbidities. Despite this, UK multiple birth rates following IVF remain higher than spontaneous conception, with 5% of IVF pregnancies resulting in multiple birth compared to 0.4%-1.2% multiple gestation rates following spontaneous conception. Owing to advancements in cryopreservation techniques, live birth and ongoing pregnancy rates are now comparable between fresh and frozen embryo transfer. Consequently, 2xSET has been suggested as an alternate technique to achieve comparable live birth rates with fewer multiple gestation pregnancies compared to DET. Study design, size, duration This retrospective cohort study was conducted using Human Fertilisation and Embryology Authority (HFEA) register data, which encompasses national data from all IVF clinics in the UK. Within this analysis, all women who underwent their first oocyte collection and IVF or ICSI treatment cycle with subsequent SET, DET or 2xSET between 2010 and 2019 using either blastocyst or cleavage stage embryos were included (N = 125,149). Participants/materials, setting, methods This national retrospective cohort study utilised UK HFEA register data from 2010-2019, including all women who underwent their first oocyte collection and subsequent embryo transfer (N = 125,149). The rate of live birth, multiple birth, preterm birth, and pregnancy loss or neonatal death was compared between SET, DET, and 2xSET IVF/ICSI pregnancies using either blastocyst or cleavage stage embryos, and was stratified by maternal age. Data analysis was conducted in RStudio v4.2, alpha equals 0.05. Main results and the role of chance 2xSET pregnancies following blastocyst-stage transfer achieved a greater live birth occurrence rate of 0.47 (0.13) (median (interquartile range)) than SET, 0.41 (0.13), and DET, 0.38 (0.13) (P &amp;lt; 0.05). When using SET as a reference standard, 2xSET achieved a lower multiple birth rate, odds ratio (OR) of 6.87 (95%CI 6.14-7.68), than DET, OR 28.20 (95%CI 25.20-31.57), and lower preterm birth rate; OR 1.11 (95%CI 1.06-1.15) in 2xSET, and OR 2.80 (95%CI 2.67-2.94) in DET. Pregnancy loss or neonatal death rate was also lower in 2xSET, OR 1.14 (95%CI 1.08-1.21), compared to DET, OR 2.11 (95%CI 1.98-2.24). Conversely, in cleavage-stage embryo transfer pregnancies, no significant difference in live birth occurrence rate was observed, achieving rates of 0.27 (0.21) for SET, 0.26 (0.13) for DET, and 0.29 (0.18) for 2xSET. 2xSET was less likely to result in multiple birth than DET, OR 0.14 (95%CI 0.11-0.19). Moreover, when using SET as a reference standard, 2xSET was less likely to result in preterm birth than DET, OR 1.02 (95%CI 0.87-1.23) and 2.48 (95%CI 2.17-2.82) respectively, as well as pregnancy loss or neonatal death, OR 1.07 (95%CI 0.85-1.35) and 2.03 (95%CI 1.70-2.42) respectively. Limitations, reasons for caution Certain confounders are not recorded within HFEA registry data, including patient body mass index (BMI), evaluation of embryo quality, and endometrial thickness at embryo transfer. Consequently, while our analysis identifies broad trends in embryo transfer success and morbidity, results may differ within certain patient populations. Wider implications of the findings 2xSET may provide greater or comparable live birth rates with lower multiple birth and morbidity than DET. Promotion of 2xSET where appropriate for maternal age and embryo quality should be implemented to enhance reproductive outcomes and reduce the risk of morbidity in IVF/ICSI pregnancies. Trial registration number Not Applicable

O-159 Domestic and cross-border reproductive care among same-sex male intended parents: comparing live birth rates (LBRs) in a national retrospective cohort in the United States (U.S.)

Abstract Study question How common is cross-border reproductive care (CBRC) in the U.S. among international same-sex male intended parents? Do CBRC LBRs differ compared to domestic counterparts? Summary answer A substantial number of international same-sex male intended parents seek CBRC in the U.S. LBRs per transfer are reassuring and comparable to domestic counterparts. What is known already Same-sex male intended parents often work with a gestational carrier to have a genetically related child(ren); however, restrictive and/or discriminatory policies in their home countries may prevent access. Intended parents may seek CBRC in countries like the U.S. due to favorable regulations. However, the volume of CBRC activity among same-sex male intended parents has been difficult to estimate accurately due to poor sexual orientation data collection. Capitalizing on national databases that identify same-sex male intended parents is the first step to describing CBRC trends and their associated outcomes in a marginalized population that is often excluded in the literature. Study design, size, duration This national retrospective cohort study included U.S. based gestational carrier embryo transfer cycles from the Society for Assisted Reproductive Technology (SART) database in the years 2017–2020. Among participating clinics (n = 488), 6,168 cycles among same-sex male intended parents were identified. Relative risks (RRs) for LBRs per transfer were compared for cycles including domestic (i.e., U.S. based, n = 3,052) and internationally based (n = 3,080) patients. LBR and country data were missing for 546 and 36 cycles, respectively. Participants/materials, setting, methods The inclusion criteria were transfer cycles among male patients with male partners. Unadjusted and adjusted RRs for LBRs per transfer were calculated to compare domestic (reference) and internationally based groups using multivariable Poisson and logistic regression models with generalized estimating equations (GEEs). Models were adjusted for donor age, transfer type (i.e., fresh, frozen), day of transfer, number of embryos transferred, male infertility, and the use of intracytoplasmic sperm injection, assisted hatching, and preimplantation genetic testing. Main results and the role of chance Between 2017 and 2020, 6,168 cycles with an embryo transfer to a gestational carrier occurred among same-sex male intended parents in the U.S. In half of the cycles, the U.S. was a destination for CBRC (50%, n = 3,080) among which (48%, n = 1,540) were from one of 23 European countries. Regarding countries of residence for CBRC cycles (n = 3,080), those most reported were China (23%), France (19%), Israel (13%), Spain (11%), the United Kingdom (6.1%), Australia (4.1%), Germany (3.7%), Italy (2.6%), Switzerland (1.5%), Canada (1.5%), Belgium (1.4%), Singapore (1.0%), Taiwan (1.2%), Norway (1.2%) and The Netherlands (0.92%). Additionally, there were 76 cycles from 8 countries in South America (2.3%), 9 cycles from 6 countries in Africa (0.27%), and 3 cycles from 2 countries in Central America (0.089%). Most cycles were in the U.S. West (72%, n = 4,441; e.g., California [47%]). Median oocyte age was 26 years (interquartile range 24,28) with a majority of cycles involving single embryo transfer (78%, n = 4,802). LBR per transfer was 69% (n = 3,867). There was no statistical difference between live births for domestic versus CBRC cycles in the unadjusted (RR 1.14, 95% confidence interval [CI] 0.96, 1.37; p: 0.141) or adjusted regression models (aRR 1.06, 95% CI 0.86, 1.32; p: 0.572). Limitations, reasons for caution The SART surveillance system captures most (∼90%) but not all embryo transfer cycles in the US. Current gender identity data were not available. Only the individual identified as the patient (and not the partner) indicated country of residence. The rationale for pursuing CBRC in the U.S could not be explored. Wider implications of the findings This study highlights a substantial amount of CBRC among same-sex male intended parents choosing the US for reproductive care. Implementing improved sexual orientation and gender identity data collection strategies are critical to filling CBRC data deserts not only among same-sex male intended parents but all sexual and gender minority populations. Trial registration number Not applicable

O09 Cutaneous squamous cell carcinoma survival in England 2004–2020: a national retrospective observational cohort study

O09 Cutaneous squamous cell carcinoma survival in England 2004–2020: a national retrospective observational cohort study

The survival benefit of deceased donor kidney transplantation for Aboriginal and Torres Strait Islander people, 2006-20: a retrospective national cohort study.

To quantify the survival benefit of kidney transplantation for Aboriginal and Torres Strait Islander people waitlisted for deceased donor kidney transplantation in Australia. Retrospective cohort study; analysis of linked data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry, the Australia and New Zealand Organ Donation (ANZOD) registry, and OrganMatch (Australian RedCross). All adult Aboriginal and Torres Strait Islander people (18 years or older) who commenced dialysis in Australia during 1 July 2006 - 31 December 2020 and were included in the kidney-only deceased donor transplant waiting list. Survival benefit of deceased donor kidney transplantation relative to remaining on dialysis. Of the 4082 Aboriginal and Torres Strait Islander people who commenced dialysis, 450 were waitlisted for kidney transplants (11%), of whom 323 received deceased donor transplants. Transplantation was associated with a significant survival benefit compared with remaining on dialysis after the first 12 months (adjusted hazard ratio [HR], 0.38; 95% confidence interval [CI], 0.20-0.73). This benefit was similar to that for waitlisted non-Indigenous people who received deceased donor kidney transplants (adjusted HR, 0.47; 95% CI, 0.40-0.57; Indigenous status interaction: P=0.22). From twelve months post-transplantation, deceased donor transplantation provides a survival benefit for Aboriginal and Torres Strait Islander people. Our findings provide evidence that supports efforts to promote the waitlisting of Aboriginal and Torres Strait Islander people who are otherwise eligible for transplantation.

Regional disparities in primary cesarean delivery rates in Japan: the role of obstetrician availability

BackgroundThe prevalence of cesarean section procedures is on the rise worldwide, necessitating a deeper understanding of the factors driving this trend to mitigate potential adverse consequences associated with unnecessary cesarean section deliveries. ObjectivesThis study aims to investigate the rate of primary cesarean deliveries (PCD), a potential key indicator of obstetric care quality. Study DesignA national retrospective cohort study was conducted utilizing extensive data from the National Database of Health Insurance Claims and Specific Health Checkups of Japan spanning the years 2012 to 2018. The study examined the temporal trends in PCD rates and the indications for these procedures across different prefectures. Additionally, the study employed the obstetrician disproportionality index, as published by the Ministry of Health, Labour, and Welfare, to assess the influence of obstetrician availability on PCD rates. ResultsThroughout the study period from 2012 to 2018, the rate of PCD in Japan remained relatively stable at approximately 14%. The primary indications for PCD in 2018 included labor arrest (18.3%), malpresentation (16.5%), nonreassuring fetal status (6.5%), and macrosomia (6.0%). Substantial regional disparities in PCD rates were observed, ranging from 8.9% to 20.4% among prefectures in 2018. Notably, prefectures categorized in the bottom 10 of the obstetrician disproportionality index exhibited significantly higher PCD rates compared to the top 10 prefectures (P=.0232), with a similar trend noted for PCD due to labor arrest (P=.0288). Furthermore, a negative correlation was identified between the obstetrician disproportionality index and PCD rates at the prefectural level (r=–0.3119, P=.0328). ConclusionsOur study presents a comprehensive analysis of PCD rates in Japan, shedding light on regional disparities and highlighting the notable influence of obstetrician availability on clinical decision-making. This study contributes to the ongoing discourse on the escalating global trend in cesarean sections and the importance of healthcare resource allocation in maternal care.

Stenosis of the colorectal anastomosis after surgery for diverticulitis: A national retrospective cohort study.

The aim of this work was to investigate the association between early postoperative anastomotic leakage or pelvic abscess (AL/PA) and symptomatic anastomotic stenosis (SAS) in patients after surgery for left colonic diverticulitis. This is a retrospective study based on a national cohort of diverticulitis surgery patients carried out by the Association Française de Chirurgie. The assessment was performed using path analyses. The database included 7053 patients operated on for colonic diverticulitis, with surgery performed electively or in an emergency, by open access or laparoscopically. Patients were excluded from the study analysis where there was (i) right-sided diverticulitis (the initial database included all consecutive patients operated on for colonic diverticulitis), (ii) no anastomosis was performed during the first procedure or (iii) missing information about stenosis, postoperative abscess or anastomotic leakage. Of the 4441 patients who were included in the final analysis, AL/PA occurred in 327 (4.6%) and SAS occurred in 82 (1.8%). AL/PA was a significant independent factor associated with a risk for occurrence of SAS (OR = 3.41, 95% CI = 1.75-6.66), as was the case for diverting stoma for ≥100 days (OR = 2.77, 95% CI = 1.32-5.82), while central vessel ligation proximal to the inferior mesenteric artery was associated with a reduced risk (OR = 0.41; 95% CI = 0.19-0.88). Diverting stoma created for <100 days or ≥100 days was also a factor associated with a risk for AL/PA (OR = 3.08, 95% CI = 2-4.75 and OR = 12.95, 95% CI = 9.11-18.50). Interestingly, no significant association between radiological drainage or surgical management of AL/PA and SAS could be highlighted. AL/PA was an independent factor associated with the risk for SAS. The treatment of AL/PA was not associated with the occurrence of anastomotic stenosis. Diverting stoma was associated with an increased risk of both AL/PA and SAS, especially if it was left for ≥100 days. Physicians must be aware of this information in order to decide on the best course of action when creating a stoma during elective or emergency surgery.

Risk of drug-related death associated with co-prescribing of gabapentinoids and Z-drugs among people receiving opioid-agonist treatment: A national retrospective cohort study

BackgroundPrescribing of gabapentinoids and Z-drug-hypnotics has increased in the population and among people receiving opioid-agonist treatment (OAT) for opioid dependence. Evidence is mixed on whether co-prescribing of sedatives such as gabapentinoids and Z-drugs during OAT increases risk of drug-related death (DRD). MethodsWe conducted a retrospective cohort study of individuals prescribed OAT between 2011 and 2020 in Scotland. Prescribing records were linked to mortality data and other healthcare datasets (sociodemographic, comorbidity). We identified episodes of treatment with gabapentinoids/Z-drugs and used multivariable quasi-Poisson regression to model associations between co-prescription and DRD risk. ResultsAmong 46,602 individuals with 304,783 person-years of follow-up, we found that co-prescription was common, with 25 % and 34 % ever being co-prescribed gabapentinoids and Z-drugs, respectively. Gabapentinoid exposure was strongly associated (adjusted hazard ratio (aHR)=2·18, 95 % CI=1·92, 2·46) and Z-drug exposure moderately associated (aHR=1·39, 95 % CI=1·15, 1·66) with elevated risk of DRD. Gabapentinoid exposure was associated with DRD risk on and off OAT; Z-drug exposure was less strongly associated with DRD risk when on OAT. ConclusionsCo-prescription of gabapentinoids and Z-drugs is common among OAT patients. However, co-prescription is associated with increased risk of DRD. Alternatives to prescribing sedative medications to OAT patients and/or greater monitoring – if prescribed – are needed.

Associations between metabolic dysfunction-associated fatty liver disease, chronic kidney disease, and abdominal obesity: a national retrospective cohort study

Metabolic dysfunction-associated fatty liver disease (MAFLD) and chronic kidney disease (CKD) present notable health challenges, however, abdominal obesity has received scant attention despite its potential role in exacerbating these conditions. Thus, we conducted a retrospective cohort study using the National Health and Nutrition Examination Surveys III (NHANES III) of the United States from 1988 to 1994 including 9161 participants, and mortality follow-up survey in 2019. Statistical analyze including univariable and multivariable Logistic and Cox regression models, and Mediation effect analyze were applied in study after adjustment for covariates. Our findings revealed that individuals with both abdominal obesity and MAFLD were more likely to be female, older and exhibit higher prevalence of advanced liver fibrosis (7.421% vs. 2.363%, p < 0.001), type 2 diabetes mellitus (T2DM) (21.484% vs. 8.318%, p < 0.001) and CKD(30.306% vs. 16.068%, p < 0.001) compared to those with MAFLD alone. MAFLD (adjusted OR: 1.392, 95% CI 1.013–1.913, p = 0.041), abdominal obesity (adjusted OR 1.456, 95% CI 1.127–1.880, p = 0.004), abdominal obesity with MAFLD (adjusted OR 1.839, 95% CI 1.377–2.456, p < 0.001), advanced fibrosis(adjusted OR 1.756, 95% CI 1.178–2.619, p = 0.006) and T2DM (adjusted OR 2.365, 95% CI 1.758–3.183, p < 0.001) were independent risk factors of CKD. The abdominal obese MAFLD group had the highest all-cause mortality as well as mortality categorized by disease during the 30-year follow-up period. Indices for measuring abdominal obesity, such as waist circumference (WC), waist-hip ratio (WHR), and lipid accumulation product (LAP), elucidated a greater mediation effect of MAFLD on CKD compared to BMI on CKD (proportion mediation 65.23%,70.68%, 71.98%, respectively vs. 32.63%). In conclusion, the coexistence of abdominal obesity and MAFLD increases the prevalence and mortality of CKD, and abdominal obesity serves as a mediator in the association between MAFLD and CKD.

Impact of COVID-19 pandemic on neurodevelopmental outcomes of premature infants: a retrospective national cohort study

ObjectiveTo compare the neurodevelopmental outcomes of preterm infants before and during the COVID-19 pandemic.DesignPremature infants born in 2018 were assigned to the pre-pandemic group, while those born in 2019 were...