The association between time-series milk β-hydroxybutyrate dynamics and early reproductive performance of dairy cows

The DeLaval Herd Navigator is an on-farm sensor system that measures on a frequent basis milk progesterone (P4) and β-hydroxybutyrate (BHB) in individual cows to closely monitor reproductive performance and energy balance. This information provides the opportunity to investigate the dynamics of BHB measured in milk (mBHB) and study the association between mBHB and early reproductive performance. The objectives of the study were (1) to describe mBHB dynamics within the first 20 d in milk (DIM), and (2) to evaluate the association between mBHB dynamics and early reproductive performance at cow-level. Two-year time-series data from 4,133 dairy cows in 38 Dutch dairy farms were available for analysis. Data included information on mBHB, daily milk yield and the indicators of early reproductive performance, days from calving to resumption of cyclicity, days from calving to first estrus, and days from calving to first insemination. The following mBHB dynamic parameters were defined based on the first 20 DIM for each individual cow: average mBHB (AvgBHB), DIM when mBHB was for the first time ≥80 μmol/L (OnsetKeto), the total number of consecutive days a cow had mBHB concentration ≥80 μmol/L, and the number of measurements mBHB concentration was ≥80 μmol/L. Three Cox proportional hazard regression models with random herd effect were developed to evaluate the association between cow level mBHB dynamics and days from calving to resumption of cyclicity, first estrus, and first insemination. Results showed that the mean AvgBHB within 20 DIM among all cows was 73 μmol/L. The mean OnsetKeto within 20 DIM, was 8 DIM. Among all cows having hyperketolactia, 55.8% (1,350/2,419) had OnsetKeto in the first week of lactation. In total, 41.5% (1,714/4,133) of the cows did not have OnsetKeto in the first 20 DIM. An early onset of hyperketolactia was associated with delayed fertility events. Cows with higher AvgBHB have a prolonged time interval from calving to resumption of cyclicity and first estrus. Information on mBHB dynamics and the association with early reproductive performance provides insights that might be helpful to improve reproductive performance of individual dairy cows.

Using a digital platform to establish odontometric variation based on race, gender and Angle classification

Orthodontists often encounter significant clinical challenges in the finishing stages of treatment due to a disproportion in interarch tooth size relationships. Despite the increasing presence of digital technology and concomitant focus on customized treatment approaches, there is a gap in the knowledge of how generating tooth size data using digital versus traditional methods may impact our treatment regime.

OBJECTIVE

This study aimed to compare the prevalence of tooth size discrepancies using digital models and a digitally based cast analysis in our cohort based on (i) Angle's Classification; (ii) gender and (iii) race.

MATERIALS AND METHODS

The mesiodistal widths of teeth in 101 digital models were assessed using computerized odontometric software. A Chi-square test was used to determine the prevalence of tooth size disproportions among the study groups. The differences between all three groups of the cohort were analysed using a three-way analysis of variance (ANOVA).

RESULTS

An overall Bolton tooth size discrepancy (TSD) prevalence of 36.6% was observed in our study cohort; 26.7% had an anterior Bolton TSD. No differences existed in the prevalence of tooth size discrepancies between male and female subjects as well as between the different malocclusion groups (P > .05). Caucasian subjects had a statistically significant smaller prevalence of TSD compared to Black and Hispanic patients (P < .05).

CONCLUSION

The prevalence results in this study illuminate how relatively common TSD is and underscores the importance of proper diagnosis. Our findings also suggest that racial background may be an influential factor in the presence of TSD.

Lifestyle and Clinical Factors in a Nationwide Stage III and IV Renal Cell Carcinoma Study

BACKGROUND

The aim was to investigate whether patient-related or clinical risk factors present at the diagnosis of advanced stage renal cell carcinoma (RCC) had an impact on the overall mortality, cancer-specific mortality, and recurrence risk in a national cohort.

METHODS

Patients registered with stage III and IV RCC in the Danish Renal Cancer Database (DaRenCa) in 2014-2016 were included in the study and followed up until recurrence or death. We conducted a Cox Proportional Hazard Model to examine the association between several variables and the development of RCC. These variables included BMI, hypertension, smoking status, symptoms at diagnosis, performance status, multidisciplinary team (MDT) discussion, surgical margin, and primary metastasis. Separate analyses were performed for cc-RCC and non-ccRCC patients.

RESULTS

In our cohort of 929 patients, 424 individuals died from RCC during the follow-up period, with a median follow-up time of 4.1 (95% CI: 0.8-5.0) years for ccRCC and 2.0 (95% CI: 0.1-5.0) years for non-ccRCC. A multivariate analysis demonstrated that a positive surgical margin (HR 1.53 and 1.43), synchronous metastasis (HR 2.06 and 3.23), and poor performance status (HR 4.73 and 5.27) were significantly associated with a decreased 5-year overall and cancer-specific survival, respectively. Furthermore, a positive surgical margin was associated with a higher risk of recurrence in ccRCC. MDT discussion was found to reduce mortality risk in non-ccRCC.

CONCLUSION

Clinical- and disease-related variables have a greater impact on RCC mortality and recurrence than the selected lifestyle-related factors. The inclusion of MDT discussion in the diagnosis and management of advanced RCC should be further evaluated for its potential to improve patient outcomes.

Psychotropic medication among children who experience parental death to cancer

The psychological consequences of losing a parent to cancer are unclear. We investigated whether experiencing parental death to cancer before 18 years of age increases the risk of psychotropic medication. We used register data of all children born in Denmark between 1 January 1987 and 31 December 2016 (N = 1,488,846). We assessed rate ratios (RRs) with 95% confidence intervals (CIs) for first redeemed prescription of antidepressants, anxiolytics and hypnotics according to parental death status using Poisson multi-state models. We further examined whether the associations differed according to the gender of the deceased parent, child's age at the time of death or the parental length of illness. Cancer-bereaved children had a significantly increased risk of first prescription of psychotropic medication (rate ratio, RR 1.22, 95% confidence interval, CI 1.10-1.34 for males; RR 1.18, 95% CI 1.09-1.28 for females). Associations were strongest if the parent had the same sex as the child and if the parent died within one year of diagnosis. The risk was highest during the first six months after the loss (RR 2.35, 95% confidence interval, CI 1.48-3.73 for males; RR 1.81, 95% CI 1.17-2.80 for females). Children who lose a parent to cancer, particularly in cases when the disease progressed quickly, may need extra psychological support, especially during the first six months after the death.

Nanoscopy and an extended lateral approach can improve the management of latero-central segments in tibial plateau fractures: a cadaveric study

Introduction

The objective of this investigation was to compare different techniques to improve visualization and reduction in tibial plateau fractures involving the central lateral segments.

Methods

Matched pairs of pre-fractured cadaveric tibial plateau fractures that include the central lateral segments were treated by either an anterolateral approach (supine) or PL approach (prone). Reduction was stepwise extended by additional fracturoscopy (FS), nanoscopy (NS) and lastly by epicondyle osteotomy (ECO). Reduction was analyzed by 3D scan and visualization of the lateral plateau was quantified.

Results

Ten specimens (3 pairs 41B3.1, 2 pairs 41C3.3) were analyzed. Fracture steps involving the antero-latero-central (ALC) segment were insufficiently reduced after fluoroscopy using both approaches (AL 2.2 ± 1.2 mm vs PL 2.2 ± 1.0 mm, p 0.95). Additional NS and ECO achieved optimized fracture reduction in the ALC segment (NS AL 1.6 ± 1.3 mm vs PL 0.8 ± 0.9 mm, p 0.32). NS provided visualization of the entire lateral plateau (PL 102.9% ± 7.4, AL 108.8 ± 19.2%), while fracturoscopy only allowed visualization of the ALL segment and partially of PLL and ALC segments (PL 22.0 ± 23.4%, AL 29.7 ± 18.3%).

Conclusion

Optimized reduction of tibial head fractures with involvement of latero-central segments requires additional video-assisted reduction or extended approaches. Nanoscopy helps visualizing of the entire lateral plateau, when compared to fracturoscopy and may become a valuable reduction aid.

Understanding quality data correctly: a randomized comparison of presentation formats among cancer patients and relatives

Background: Patient representatives are increasingly engaged in quality in health care, and even though quality data are publicly available, correct interpretation may be challenging. We designed a randomized study with the primary aim to examine the association between preferred data presentation format and the interpretation of quality data among cancer patients and relatives.Material and methods: Surveys were distributed to the Danish Cancer Society Citizens' Panel between 31 March and 14 April 2019 and 55% completed the survey (N = 464) including six storyboards that presented authentic quality data in table format, league table and point estimates. The storyboards were randomized to expose participants to the data in the three different formats and in varying presentation order. Logistic regression models were used to calculate Odds Ratios (ORs) and 95% confidence intervals (CIs) for the association between preferred presentation format, health literacy, education and cohabitation status as exposures and interpretation of quality data as outcome.Results: The majority of participants (97%) had high literacy and 57% had a medium or long higher education. A total of 60% found the questions difficult or very difficult and 33% were not able to correctly interpret at least one format. Correct interpretation was associated with preferred league table (OR = 1.62; 95% CI = 1.04-5.52) and if the data was presented in the preferred format. Medium and long education were associated with correct interpretation of at least one format (OR = 1.93; 95% CI = 1.16-3.21 and OR = 3.89; 95% CI = 1.90-7.95, respectively) while health literacy and cohabitation status were not.Conclusions: More than one third of the participants were not able to correctly interpret the data and the understanding of quality data improved with longer education and if the data was presented in the preferred format. Decision-makers should carefully consider displaying quality data according to preferred presentation format and to guide interpretation for individuals with short education.

Are loneliness interventions effective in reducing loneliness? A meta-analytic review of 128 studies

 

Loneliness is widely acknowledged as a growing public health concern, accelerated by the onset of the COVID-19 pandemic. However, our knowledge about the effectiveness of interventions to reduce loneliness across the lifespan, including knowledge of different intervention strategies, is limited. This preregistered systematic review and meta-analysis aimed to evaluate the effect of interventions to reduce loneliness. The systematic review identified 136 studies. The meta-analysis included 128 studies comprising 54 randomised controlled trials (RCTs) (n = 6,379), 23 multi-cohort studies (n = 2,882) and 48 single-cohort studies (n = 3,009). A small to moderate statistically significant effect was detected (RCTs; SMD = -0.47, multi-cohort studies; SMD = -0.24, single cohort-studies; SMD = -0.42). Using the GRADE system, confidence in the estimates was assessed as low or very low, implying that the estimates may potentially be higher or lower. No statistically significant differences were found between age groups. Psychological treatment, social support interventions, and social and emotional skills training appeared to be the most effective intervention strategies in reducing loneliness but there is currently no strong reason to prefer one intervention strategy over another. Further analyses demonstrated that the long-term effects (i.e., one to six months after the intervention) were comparable to the short-term effects (i.e., up to four weeks after the intervention). Findings from the current meta-analyses provide overall evidence of the effectiveness of loneliness interventions. Given methodological limitations, including the heterogeneity of the reviewed studies, it remains unclear who the interventions would help the most. Overall, there is a need for rigorous and high-quality development and evaluations of interventions for loneliness.

Key messages

• The findings of this meta-analytic review suggest that interventions designed to reduce loneliness are effective.

• Psychological treatment, social support interventions, and social and emotional skills training are the most promising interventions, albeit the magnitude of the effects is moderate.

The association of loneliness and social isolation with healthcare utilization in Denmark

Objectives

The present prospective cohort study investigated the association of loneliness and social isolation (SI) with healthcare utilization (HCU) in the general population over time.

Methods

Data from the 2013 Danish “How are you?’ survey (n = 29,472) were combined with individual-level register data from the National Danish Patient Registry and the Danish National Health Service Registry over a 6-year follow-up period (2013-2018). Negative binomial regression analyses were performed while adjusting for baseline demographics and chronic disease.

Results

Loneliness measured at baseline was significantly associated with more GP contacts (incident-rate ratio (IRR) = 1.03, 95% confidence interval (CI) [1.02, 1.04]), more emergency treatments (IRR = 1.06, 95% CI [1.03, 1.10]), more emergency admissions (IRR = 1.06, 95% CI [1.03, 1.06]), and hospital admission days (IRR=1.05, 95% CI [1.00, 1.11]) across the 6-year follow-up period. No significant associations were found between social isolation and HCU with one minor exception, in which SI was associated with fewer planned outpatient treatments (IRR = .97, 95% CI [.94, .99]).

Conclusions

Our findings suggest that loneliness is a risk factor for certain types of HCU, independent of social isolation, baseline demographics, and chronic disease.

Key messages

Overall and stage-specific survival of patients with screen-detected colorectal cancer in European countries: A population-based study in 9 countries

Background

An increasing proportion of colorectal cancers (CRCs) are detected through screening due to the availability of organised population-based programmes. We aimed to analyse survival probabilities of patients with screen-detected CRC in European countries.

Methods

Data from CRC patients were obtained from 16 population-based cancer registries in nine European countries. We included patients with cancer diagnosed from the year organised CRC screening programmes were introduced until the most recent year with available data at the time of analysis, whose ages at diagnosis fell into the age groups targeted by screening. Patients were followed up with regards to vital status until 2016-2020 across the various countries. Overall and CRC-specific survival were analysed by mode of detection and stage at diagnosis for all countries combined and for each country separately using the Kaplan-Meier method.

Findings

We included data from 228 134 patients, of whom 134 597 (aged 60-69 years at diagnosis targeted by screening in all countries) were considered in analyses for all countries combined. 22·3% (38 080/134 597) of patients had cancer detected through screening. Most screen-detected cancers were found at stages I-II (65·6% [12 772/19 469 included in stage-specific analyses]), while the majority of non-screen-detected cancers were found at stages III-IV (56·4% [31 882/56 543 included in stage-specific analyses]). Five-year overall and CRC-specific survival rates for patients with screen-detected cancer were 83·4% (95% CI 82·9-83·9) and 89·2% (88·8-89·7), respectively; for patients with non-screen-detected cancer, they were much lower (57·5% [57·2-57·8] and 65·7% [65·4-66·1], respectively). The favourable survival of patients with screen-detected cancer was also seen within each stage – five-year overall survival rates for patients with screen-detected stage I, II, III, and IV cancers were 92.4% (95% CI 91·6-93·1), 87·9% (86·6-89·1), 80·7% (79·3-82·0), and 32·3 (29·4-35·2), respectively. These patterns were also consistently seen for each individual country.

Interpretation

Patients with cancer diagnosed at screening have a very favourable prognosis. In the rare case of detection of advanced stage cancer, survival probabilities are still much higher than those commonly reported for all patients regardless of mode of detection. Although these results cannot be taken to quantify screening effects, they provide useful and encouraging information for patients with screen-detected CRC and their physicians.

Funding

This study was supported in part by grants from the German Federal Ministry of Education and Research and the German Cancer Aid.

POS0298 OCCURRENCE AND PREDICTION OF FLARE AFTER TAPERING OF TNF INHIBITORS IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS

Background

Patients with axial spondyloarthritis (axSpA) in clinical remission tapered Tumor Necrosis Factor inhibitor (TNFi) therapy according to a clinical guideline and had 2 years´ follow-up [1].

Objectives

We aimed to investigate flare frequency, dose at which flare occurred, type of flare (clinical/ Bath ankylosing spondylitis disease activity index (BASDAI)/magnetic resonance imaging (MRI)) and predictors of flare.

Methods

Patients in clinical remission (BASDAI<40, physician global score<40 and without disease activity the previous year) tapered TNFi to 2/3 standard dose at baseline, 1/2 at week (w)16, 1/3 at w32 and 0 (discontinuation) at w48. Patients who flared were increased to previous dose. Predictors of flare at each dose step were investigated by regression analyses.

Results

Of 108 patients, 106 (99%) flared before year 2 (flare occurring mean (SD) 99(44.3) days after last tapering). Twenty-nine patients (27%) flared at 2/3 standard dose, 21 (20%) at 1/2 dose, 29 (27%) at 1/3 dose and 27 (25%) after discontinuation. One-hundred-and-five (99%) had clinical flare, 25 (24%) BASDAI flare and 23 (29% of patients with MRI at flare) MRI flare; and forty-one patients (41%) fulfilled the ASAS-definition of clinically important worsening (≥0.9 increase since baseline) (Figure 1). Most common flare symptoms were back/buttock pain (n=93 (89%)) and pain in peripheral joints/entheseal regions (n=48 (46%)). Higher baseline physician global score was an independent predictor of flare after tapering to 2/3 (Odds ratio=1.19 (95% Confidence Interval=1.05-1.41); p=0.011) (Table 1). Changes in clinical and/or imaging variables in the 16 weeks prior to tapering did not predict flare (data not shown).

Table 1.

Prediction of flare within 16 weeks after tapering to 2/3 dose (n=74)

Values are from timepoint of tapering from full dose to 2/3 doseUnivariate analysesFinal multivariable analyses*OR(95% CI)p-valueOR(95% CI)p-valueMale gender0.96(0.25 - 4.14)0.955Age1.00(0.96 - 1.04)0.880Time since diagnosis1.00(0.95 - 1.06)0.863Current smoker0.70(0.20 - 2.20)0.543HLA-B27 positive0.66(0.18 - 2.41)0.515Previous bDMARDs1.28(0.66 - 2.49)0.458Patient pain VAS1.02(0.98 - 1.06)0.310Physician global VAS1.19(1.04 - 1.41)0.0121.19(1.04 - 1.41)0.011ASDAS1.66(0.70 - 4.10)0.251mNYc positive0.78(0.29 - 2.09)0.615SPARCC SIJ Inflammation Index1.01(0.90 - 1.12)0.861CANDEN Total inflammation0.95(0.65 - 1.25)0.702SPARCC SSS Erosion1.11(0.91 - 1.37)0.293CANDEN Fat0.99(0.96 - 1.02)0.705AUC (95% CI)0.66 (0.54 - 0.78)

Predictors were selected by applying backward selection in stacked data. p-values by likelihood ratio tests. Bold indicates p-values<0.1 in univariate analyses. Predictors were selected by backward selection in stacked imputed datasets after applying a fixed weight to all observations, accounting for the average fraction of missing data across all variables under consideration. *Results were derived in non-imputed data (no missing values in selected predictors). CIs given as profile likelihood CIs. AUC estimated based on internal validation by bootstrapping with 1000 samples.

ASDAS, Ankylosing Spondylitis Disease Activity Score; bDMARDs, biological disease modifying anti-rheumatic drugs; AUC, Area Under the receiver operating characteristic Curve; CANDEN, Canada-Denmark MRI scoring system of the spine in patients with axial spondyloarthritis; CI, confidence interval; mNYc, modified New York criteria; SIJ, sacroiliac joint; SPARCC SIJ inflammation, Spondyloarthritis Research Consortium of Canada Sacroiliac joint inflammation; SPARCC SSS, Spondyloarthritis Research Consortium of Canada Sacroiliac joint Structural Score; VAS, visual analogue scale.

Conclusion

Almost all (99%) axSpA patients in clinical remission flared during tapering to discontinuation, but above half not before receiving 1/3 dose or less. Higher physician global score was the only independent predictor of flare.

References

[1]Wetterslev M, et al. Rheumatology (Oxford) 2021;10.1093/rheumatology/keab755.

Disclosure of Interests

Marie Wetterslev: None declared, Stylianos Georgiadis: None declared, Sara Nysom Christiansen Speakers bureau: BMS and GE, Grant/research support from: Novartis, Susanne Juhl Pedersen Speakers bureau: MSD, Pfizer, AbbVie, Novartis and UCB, Consultant of: AbbVie and Novartis, Grant/research support from: AbbVie, MSD, and Novartis, Inge Juul Sørensen: None declared, Merete Lund Hetland Consultant of: MSD, Biogen, Pfizer, Eli Lilly, Orion Pharma, CellTrion, Samsung Bioepis, and Janssen Biologics BV, Grant/research support from: MSD, Biogen, Pfizer, Bristol-Myers Squibb, AbbVie, Roche and Novartis, Anne Duer: None declared, Mikael Boesen Speakers bureau: Image Analysis Group, Esaote, AbbVie, Celgene, Eli-Lilly, Janssen, Novartis, Pfizer, UCB, Novo, GSK, Takeda, Geurbet, Biogen, Radiobotics and Chondrometrics, Consultant of: Image Analysis Group, Esaote, AbbVie, Celgene, Eli-Lilly, Janssen, Novartis, Pfizer, UCB, Novo, GSK, Takeda, Geurbet, Biogen, Radiobotics and Chondrometrics, Grant/research support from: Image Analysis Group, Esaote, AbbVie, Celgene, Eli-Lilly, Janssen, Novartis, Pfizer, UCB, Novo, GSK, Takeda, Geurbet, Biogen, Radiobotics and Chondrometrics, Kasper K Gosvig: None declared, Jakob Møllenbach Møller: None declared, Mads Bakkegaard: None declared, Cecilie Heegaard Brahe: None declared, Niels Steen Krogh: None declared, Bente Jensen: None declared, Ole Madsen: None declared, Jan Christensen: None declared, Annette Hansen Speakers bureau: speaker fees from Elly Lilly, Jesper Noerregaard: None declared, Henrik Røgind: None declared, Mikkel Østergaard Speakers bureau: Abbvie, BMS, Boehringer-Ingelheim, Celgene, Eli-Lilly, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sandoz, Sanofi and UCB, Consultant of: Abbvie, BMS, Boehringer-Ingelheim, Celgene, Eli-Lilly, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sandoz, Sanofi and UCB, Grant/research support from: Abbvie, BMS, Boehringer-Ingelheim, Celgene, Eli-Lilly, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron, Roche, Sandoz, Sanofi and UCB

Oophorectomy and rate of dementia: a prospective cohort study

OBJECTIVE

Globally, dementia disproportionally affects women, which is not fully explained by higher female longevity. Oophorectomy at any age leads to the permanent loss of ovarian sex steroids, potentially increasing the risk of dementia. We aimed to investigate the association between oophorectomy and dementia and whether this was conditional on age at oophorectomy, hysterectomy or use of hormone therapy (HT).

METHODS

A prospective study of 24,851 female nurses from the Danish Nurse Cohort. Nurses were followed from age 60 years or entry into the cohort, whichever came last, until date of dementia, death, emigration or end of follow-up (December 31, 2018), whichever came first. Poisson regression models with log-transformed person-years as offset were used to estimate the associations.

RESULTS

During 334,420 person-years of follow-up, 1,238 (5.0%) nurses developed dementia and 1,969 (7.9%)/ 1,016 (4.1%) contributed person-time after bilateral-/unilateral oophorectomy. In adjusted analyses, an 18% higher rate of dementia was observed following bilateral oophorectomy (aRR 1.18: 95% CI, 0.89-1.56) and 13% lower rate (aRR 0.87: 95% CI, 0.59-1.23) following unilateral oophorectomy compared to nurses who retained their ovaries. Similar effects were detected after stratification according to age at oophorectomy. No statistically significant modifying effects of hysterectomy or HT were detected (Pinteraction≥0.60).

CONCLUSIONS

Bilateral, but not unilateral, oophorectomy was associated with an increased rate of incident dementia. We were unable to establish whether this association was conditional on hysterectomy or HT use. Although an increase in dementia after bilateral oophorectomy is biologically plausible, limited statistical power hampers the precision of the estimates.

Effects of early maternal cancer and fertility treatment on the risk of adverse birth outcomes

BACKGROUND

Early maternal cancer and fertility treatment each increase the risk for adverse birth outcomes, but the joint effect of these outcomes has not yet been reported. Thus, the aim was to assess the individual and joint effect of maternal cancer and fertility treatment on the risk for adverse birth outcomes.

METHODS

This population-based cohort study included 5487 live-born singletons identified in the Danish Medical Birth Register (1994-2016) of mothers with previous cancer (<40 years) recorded in the Danish Cancer Registry (1955-2014). We randomly selected 80,262 live-born singletons of mothers with no cancer <40 years matched to mothers with cancer by birth year and month. We calculated odds ratios (ORs) for preterm birth, low birth weight (LBW) (<2500 g) and small for gestational age (SGA), mean differences in birth weight in grams, and additional cases of preterm birth (gestational age<259 days) per 100,000 person-years. Multiplicative and additive interaction of maternal cancer and fertility treatment was compared with outcomes of children conceived naturally to mothers with no maternal cancer (reference group).

FINDINGS

Among 84,332 live-born singletons, increased ORs for preterm birth were observed among children born to mothers with previous cancer (1·48, 95% confidence interval [CI] 1·33-1.65) or after fertility treatment (1·43, 95% 1·28-1-61), with 22 additional cases of preterm birth among both group of children (95% CI 15-29; 95% CI 14-30). In the joint analyses, the OR for SGA for children born after fertility treatment to mothers with previous cancer was similar to that of the reference group (OR 1·02, 95% CI 0·72-1·44, P for interaction=0·52). Children with both exposures had increased ORs for LBW (1·86, 95% CI 1·17-2·96, P for interaction=0·06) and preterm birth (2·31, 955 CI 1·66-3·20, P for interaction = 0·56), with 61 additional cases of preterm birth (95% CI 27-95, P for interaction=0.26) over that of children in the reference group. The mean birth weight was also lower in children born to mothers with both exposures (-140 g, 95% CI -215; -65) (P for interaction=0.06) but decreased to -22 g (95% CI -76; 31) after adjustment for GA.

INTERPRETATION

Although we did not find any statistically significant additive interaction between maternal cancer and fertility treatment, children born after fertility treatment of mothers with previous cancer were at increased risk for adverse birth outcomes. Thus, pregnant women with both exposures need close follow-up during pregnancy.

FUNDING

The Danish Cancer Society and the Danish Childhood Cancer Foundation.

Molecular diagnostics of Salmonella and Campylobacter in human/animal fecal samples remain feasible after long-term sample storage without specific requirements

Rapid advances in the development of sequencing technologies, numbers of commercial providers and diminishing costs have made DNA-based identification and diagnostics increasingly accessible to doctors and laboratories, eliminating the need for local investments in expensive technology and training or hiring of skilled technicians. However, reliable and comparable molecular analyses of bacteria in stool samples are dependent on storage and workflow conditions that do not introduce post-sampling bias, the most important factor being the need to keep the DNA at a stable detectable level. For that reason, there may remain other prohibitively costly requirements for cooling or freezing equipment or special chemical additives.

This study investigates the diagnostic detectability of Salmonella and Campylobacter DNA in human, pig and chicken stool samples, stored at different temperatures and with different preservation methods. Stool samples were spiked with 10⁶ CFU/mL of both Salmonella and Campylobacter strains stored at −20 °C, 5 °C and 20 °C (Room temperature, RT) and treated with either RNAlater, EDTA or Silica/ethanol. DNA was extracted at 9 different time points within 30 days and quantified by Qubit (total DNA) and qPCR (Salmonella and Campylobacter DNA). We found no statistically significant differences among the different preservation methods, and DNA from both species was easily detected at all time points and at all temperatures, both with and without preservation. This suggests that infections by these bacteria can be diagnosed and possibly also analysed in further detail simply by taking a stool sample in any suitable sealed container that can be transported to laboratory analysis without special storage or preservation requirements. We briefly discuss how this finding can benefit infection control in both developed and developing countries.

The long-term association between bilateral oophorectomy and depression: a prospective cohort study

OBJECTIVE

Depression is a leading cause of disability globally and affects more women than men. Ovarian sex steroids are thought to modify depression risk in women and interventions such as bilateral oophorectomy that permanently change the sex steroid milieu may increase the risk of depression. This study aimed to investigate the associations between unilateral and bilateral oophorectomy and depression over a 25-year period (1993-2018) and whether this varied by age at oophorectomy or use of menopausal hormone therapy.

METHODS

Twenty-five thousand one hundred eighty-eight nurses aged ≥45 years from the Danish Nurse Cohort were included. Nurses with depression prior to baseline were excluded. Poisson regression models, with log-transformed person-years as offset, were used to assess the associations between oophorectomy and incident depression. Nurses who retained their ovaries were the reference group.

RESULTS

Compared with nurses with retained ovaries, bilateral oophorectomy was associated with a slightly higher rate of depression (rate ratio [RR], 1.08; 95% confidence interval [CI], 0.95-1.23), but without statistical significance. However, when stratified by age at oophorectomy, compared with nurses with retained ovaries, bilateral oophorectomy at age ≥51 years was associated with higher rates of depression (RR 1.16; 95% CI, 1.00-1.34), but not bilateral oophorectomy at age <51 years (RR 0.86; 95% CI, 0.69-1.07); P value for difference in estimates = 0.02. No association between unilateral oophorectomy and depression was observed.

CONCLUSIONS

In this cohort of Danish female nurses, bilateral oophorectomy at age ≥51 years, but not at younger ages, was associated with a slightly higher rate of depression compared with those who retained their ovaries.

Bilateral oophorectomy and rate of colorectal cancer: A prospective cohort study

Worldwide, colorectal cancer is the second most common cancer and third cause of cancer death in women. Estrogen exposure has been inversely associated with colorectal cancer. Oophorectomy reduces circulating estrogen, but the effect on colorectal cancer remains uncertain. The aim of this study was to examine the association between unilateral and bilateral oophorectomy and subsequent risk of colorectal cancer, and whether this association varied by menopausal status at time of oophorectomy, use of hormone replacement therapy (HRT) at baseline, hysterectomy and baseline body mass index (BMI). The study included 25 698 female nurses (aged ≥45 years) participating in the Danish Nurse Cohort. Nurses were followed from baseline until date of colorectal cancer, death, emigration or end of follow-up at December 31, 2018, whichever came first. We examined the association between oophorectomy and colorectal cancer (all ages and stratified by menopausal status). The potential modifying effects of hysterectomy, HRT use at baseline and BMI were investigated. During 542 140 person-years of follow-up, 863 (3.4%) nurses were diagnosed with colorectal cancer. Bilateral oophorectomy was associated with a 79% increased colorectal cancer rate, adjusted rate ratio (aRR) (95% confidence interval [CI]): 1.79 (1.33-2.42). Effect estimates following unilateral oophorectomy also showed higher rate of colorectal cancer, although less pronounced and nonstatistically significant (aRR) (95% CI): 1.25 (0.86-1.82). Similar results were seen when stratifying by menopausal status. The association was not modified by baseline HRT use, hysterectomy or BMI. Oophorectomy was associated with increased rate of colorectal cancer, with highest rates among women with bilateral oophorectomy.

Impact of comorbidity on renal cell carcinoma prognosis: a nationwide cohort study

BACKGROUND

Presence of comorbid diseases at time of cancer diagnosis may affect prognosis. We evaluated the impact of comorbidity on survival of patients diagnosed with renal cell carcinoma (RCC), overall and among younger (<70 years) and older (≥70 years) patients.

METHODS

We established a nationwide register-based cohort of 7894 patients aged ≥18 years diagnosed with RCC in Denmark between 2006 and 2017. We computed 1- and 5-year overall survival and hazard ratios (HRs) for death according to the Charlson Comorbidity Index (CCI) score.

RESULTS

Survival decreased with increasing CCI score despite an overall increase in survival over time. The 5-year survival rate of patients with no comorbidity increased from 57% among those diagnosed in 2006-2008 to 69% among those diagnosed in 2012-2014. During the same periods, the survival rate increased from 46% to 62% among patients with a CCI score of 1-2 and from 39% to 44% for those with a CCI score of ≥3. Patients with CCI scores of 1-2 and ≥3 had higher mortality rates than patients with no registered comorbidity (HR 1.15, 95% CI 1.06-1.24 and HR 1.56, 95% CI 1.40-1.73). Patterns were similar for older and younger patients. Particularly, diagnoses of liver disease (HR 2.09, 95% CI 1.53-2.84 and HR 4.01, 95% CI 2.44-6.56) and dementia (HR 2.16, 95% CI 1.34-3.48) increased mortality.

CONCLUSION

Comorbidity decreased the survival of patients with RCC, irrespective of age, despite an overall increasing survival over time. These results highlight the importance of focusing on comorbidity in this group of patients.

Cardiovascular mortality after bilateral oophorectomy: a prospective cohort study

OBJECTIVES

Bilateral oophorectomy permanently reduces endogenous estrogen exposure and may increase cardiovascular mortality in women. This study aimed to investigate the association between bilateral oophorectomy and cardiovascular mortality and whether this association was conditional on hysterectomy or on the use of hormone therapy at the time of study entry.

METHODS

A prospective cohort study of 25,338 female nurses aged ≥ 45 years within the Danish Nurse Cohort. Nurses were enrolled in 1993 or 1999 and followed until death, emigration, or end of follow-up on December 31, 2018, whichever came first. Exposure was bilateral oophorectomy. Outcome was cardiovascular mortality. Associations were estimated using Poisson regression models with log person-years as the offset.

RESULTS

A total of 2,040 (8.1%) participants underwent bilateral oophorectomy. During a mean follow-up of 21.2 (SD: 5.6) years, 772 (3.0%) nurses died from cardiovascular disease. In adjusted analyses, a 31% higher rate of cardiovascular mortality was observed after bilateral oophorectomy (aMRR 1.31; 95% CI, 0.88-1.96) compared with women who retained their ovaries. No evidence of effect modification by use of hormone therapy at baseline or by hysterectomy on the association between bilateral oophorectomy and cardiovascular mortality was observed.

CONCLUSION

Bilateral oophorectomy may be associated with cardiovascular mortality in women, but the estimate was not statistically significant. Additionally, we were unable to make firm conclusions regarding the possible modifying role of hormone therapy and hysterectomy on this potential association. Additional studies are needed to replicate this work.

Prediction of the postoperative 90-day mortality after acute colorectal cancer surgery: development and temporal validation of the ACORCA model

PURPOSE

The aim of this study was to develop and validate a model to predict 90-day mortality after acute colorectal cancer surgery.

METHODS

The model was developed in all patients undergoing acute colorectal cancer surgery in 2014-2016 and validated in a patient group operated in 2017 in Denmark. The outcome was 90-day mortality. Tested predictor variables were age, sex, performance status, BMI, smoking, alcohol, education level, cohabitation status, tumour localization and primary surgical procedure. Variables were selected according to the smallest Akaike information criterion. The model was shrunken by bootstrapping. Discrimination was evaluated with a receiver operated characteristic curve, calibration with a calibration slope and the accuracy with a Brier score.

RESULTS

A total of 1450 patients were included for development of the model and 451 patients for validation. The 90-day mortality rate was 19% and 20%, respectively. Age, performance status, alcohol, smoking and primary surgical procedure were the final variables included in the model. Discrimination (AUC = 0.79), calibration (slope = 1.04, intercept = 0.04) and accuracy (brier score = 0.13) were good in the developed model. In the temporal validation, discrimination (AUC = 0.80) and accuracy (brier score = 0.13) were good, and calibration was acceptable (slope = 1.19, intercept = 0.52).

CONCLUSION

We developed prediction model for 90-day mortality after acute colorectal cancer surgery that may be a promising tool for surgeons to identify patients at risk of postoperative mortality.

POS0025 INCIDENCE RATES AND POINT PREVALENCE OF SEROPOSITIVE AND SERONEGATIVE RHEUMATOID ARTHRITIS IN DENMARK: A NATIONWIDE REGISTER-BASED STUDY FROM 1998 TO 2018 USING FOUR DIFFERENT CASE CRITERIA

Background:

Few previous studies have investigated the incidence rate (IR) and point prevalence (PP) of seropositive and seronegative rheumatoid arthritis (RA), and further, the estimates remain unknown in the Danish population.

Objectives:

To investigate the IR and PP of seropositive and seronegative RA in the adult Danish population from 1998 to 2018 using four register-based case definitions of RA.

Methods:

Nationwide register-based cohort study. Using the Danish administrative registers, patients with RA between 1998 and end of 2018 were identified. ICD-10 codes for RA were identified in the Danish National Patient Registry and information on DMARD prescriptions were obtained through the Danish National Prescription Registry using ATC codes. The used case definitions were1: Criteria A, first time M05/M06 RA diagnosis and redemption of a DMARD in the following year; Criteria B, two RA diagnoses within 90 days of each other, originating from department of rheumatology or general internal medicine, where the latest registered M05/M06 diagnosis defined the serologic status; Criteria C, a M05/M06 diagnosis recorded at any time preceded or followed by redemption of a DMARD prescription within one year, where the M05/M06 diagnosis recorded determined the serologic status; Criteria D, as Criteria A, but with the additional requirements that cases had no registration for other selected inflammatory diseases.

In calculation of IRs the total Danish population from 1998 to 2018 was used as reference population for standardisation. The PP was calculated for years 2000, 2009, 2011 and 2018.

Results:

From 1998 to 2018 the overall IR was 18.0 (95%CI 17.7 to 18.3) per 100,000 person years (PY) for seropositive RA and 16.7 (95%CI 16.4 to 16.9) per 100,000 PY for seronegative RA using Criteria A. A higher IR for seropositive RA than for seronegative RA was found regardless of the case criteria used. Figure 1 shows the temporal IRs of seropositive and seronegative RA.

Regardless of case criteria used, the PP increased from 2000 to 2018 for both seropositive and seronegative RA, and the estimates were higher for seropositive RA than for seronegative RA (Table 1).

Table 1.

Point prevalence of rheumatoid arthritis in Denmark in year 2000, 2009, 2011 and 2018 using four different case definitions

2000200920112018SeropositiveSeronegativeSeropositiveSeronegativeSeropositiveSeronegativeSeropositiveSeronegativeCriteria AN3029274174747127871281211243711662Population3964040416629842028914269677PP, % (95%CI)0.08 (0.08 to 0.08)0.07 (0.07 to 0.07)0.18 (0.18 to 0.19)0.17 (0.17 to 0.18)0.21 (0.20 to 0.21)0.19 (0.19 to 0.20)0.27 (0.27 to 0.28)0.26 (0.25 to 0.26)Criteria BN7507489311565903312710100111633413340PP, % (95%CI)0.20 (0.19 to 0.20)0.13 (0.12 to 0.13)0.28 (0.28 to 0.29)0.22 (0.21 to 0.22)0.30 (0.30 to 0.31)0.24 (0.23 to 0.24)0.36 (0.35 to 0.36)0.29 (0.29 to 0.30)Criteria CN6701457011174912512417101491588113712PP, % (95%CI)0.18 (0.17 to 0.18)0.12 (0.12 to 0.12)0.27 (0.27 to 0.28)0.22 (0.22 to 0.23)0.29 (0.29 to 0.30)0.24 (0.24 to 0.25)0.35 (0.34 to 0.35)0.30 (0.30 to 0.31)Criteria DN272423906612598476956759108309452PP, % (95%CI)0.07 (0.07 to 0.07)0.06 (0.06 to 0.07)0.16 (0.16 to 0.16)0.15 (0.14 to 0.15)0.18 (0.18 to 0.19)0.16 (0.16 to 0.17)0.24 (0.23 to 0.24)0.21 (0.20 to 0.21)

PP = Point prevalence

Conclusion:

In Denmark, the IR and PP estimates were higher for seropositive compared to seronegative RA during the study period. However, when applying stricter case criteria for RA (Criteria A and D) the differences in IR and PP estimates were smaller, than when using less strict criteria (Criteria B and C). The findings of such small differences between seropositive and seronegative IRs warrant further investigation.

References:

[1]Soussi BG et al. Incidence and prevalence of rheumatoid arthritis in Denmark: a nationwide population based study investigating the effect of four different case definitions [abstract]. Ann Rheum Dis. 2020;79(supplement 1):46

Acknowledgements:

The authors will like to thank The Danish Rheumatism Association for supporting this work.

Disclosure of Interests:

Bolette Gylden Soussi: None declared, René Lindholm Cordtz: None declared, Salome Kristensen: None declared, Christian Sørensen Bork: None declared, Jeppe Christensen: None declared, Erik Berg Schmidt: None declared, Daniel Prieto-Alhambra Grant/research support from: Grants from AMGEN, UCB Biopharma and Les Laboratoires Servier; and Janssen, on behalf of IMI-funded EHDEN and EMIF consortiums, and Synapse Management Partners have supported training programmes organised by DPA’s department and open for external participants, Lene Dreyer Grant/research support from: Grants from BMS, Galderma and Eli Lilly.

Maternal use of hormonal contraception and epilepsy in offspring

STUDY QUESTION

Is maternal use of hormonal contraception associated with the development of epilepsy in the offspring?

SUMMARY ANSWER

We found that maternal use of hormonal contraception was associated with a slightly increased risk of epilepsy in the offspring.

WHAT IS KNOWN ALREADY

Foetal exposure to exogenous hormones has been associated with changes in brain development. However, little is known about maternal hormonal contraception use and development of epilepsy in the offspring.

STUDY DESIGN, SIZE, DURATION

A nationwide cohort of all live born children born in Denmark between 1 January 1998 and 31 December 2014, was followed from day 29 after birth for epilepsy (first diagnosis of epilepsy or first redeemed prescription for anti-epileptic medication) to censoring (emigration, death) or 31 December 2015, whichever occurred first.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Diagnoses of epilepsy were obtained from the National Patient Registry. The Danish National Prescription Registry supplied information on redeemed prescriptions for hormonal contraception and anti-epileptic medication. Maternal hormonal contraception use was categorized as never use (reference group), previous use (prescriptions redeemed >3 months before pregnancy start) and recent use (prescriptions redeemed ≤3 months before or during pregnancy).

MAIN RESULTS AND THE ROLE OF CHANCE

The data show that 17 585 children developed epilepsy during a median follow-up of 9.2 years (9 732 635 person-years). The hazard ratio (HR) for epilepsy was 1.07 (95% CI 1.02-1.13) in children of mothers who had used any type of hormonal contraception recently, compared with children of mothers who had not used hormonal contraception. The HR was similar for recent use of oral combined products, while the HRs for recent or previous use of non-oral combined products were 1.32 (95% CI 0.98-1.77) and 1.16 (95% CI 1.02-1.32), respectively. For non-oral progestin-only products, the HRs were 1.19 (95% CI 1.04-1.38) and 1.53 (95% CI 1.31-1.80), respectively, for recent and previous use.

LIMITATIONS, REASONS FOR CAUTION

There may be some misclassification of maternal hormonal contraception use, as some women may not have used the redeemed prescriptions or used them at a different point in time; potentially leading to an attenuation of the estimates. In addition, although we were able to account for known risk factors for epilepsy, unknown or residual confounding cannot be ruled out.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings are based on nationwide population-based data and can therefore be applied to other similar populations. However, as this is the first study in this field, further studies are needed to confirm our findings.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was obtained for this study, which was supported by internal funding at the Unit of Virus, Lifestyle and Genes. All authors report no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Breast cancer rate after oophorectomy: A Prospective Danish Cohort Study

The association between oophorectomy and risk of breast cancer in the general population is uncertain. The aim of our study was to determine the breast cancer rate in women from the general population after oophorectomy (performed before/after menopause), and whether this varies by use of hormone replacement therapy (HRT), hysterectomy, body mass index (BMI) and shift work. The study included 24 409 female nurses (aged ≥45 years) participating in the Danish Nurse Cohort. Nurses were followed from cohort entry until date of breast cancer, death, emigration or end of follow-up at 31 December 2018, whichever came first. Poisson regression with log-transformed person-years as the offset examined the association between oophorectomy and breast cancer (all ages and stratified by menopausal status at time of oophorectomy). The potential modifying effect of HRT use, hysterectomy, BMI and shift work on the associations was estimated. During 502 463 person-years of follow-up, 1975 (8.1%) nurses were diagnosed with breast cancer. Bilateral oophorectomy was associated with a reduced breast cancer rate compared to nurses with preserved ovaries, adjusted rate ratio (95% confidence interval): 0.79 (0.64; 0.99). Similar associations (magnitude and direction) were detected for unilateral oophorectomy and when stratifying according to menopausal status at time of oophorectomy, but without statistical significance. Unilateral and bilateral oophorectomy is associated with a reduced breast cancer rate in women from the general population. This association is not modified by use of HRT, hysterectomy, BMI or shift work.

Impact of comorbidity burden on renal cell carcinoma prognosis: A Danish nationwide cohort study

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Background: The incidence of renal cell carcinoma is increasing worldwide and have a 5-year relative survival rates of around 75%. Comorbidity has been found to be associated with complications and mortality after renal cancer surgery. No studies have focused on comorbidity as a prognostic factor in a nationwide cohort of patients with renal cell carcinoma with long-term follow-up. Purpose: The primary aim was to evaluate the prognostic impact of comorbidity on survival in older (≥70 years) and younger (<70 years) patients diagnosed with renal cell carcinoma. Methods: We established a nationwide register-based cohort of 7,894 patients aged 18 or more diagnosed with renal cell carcinoma in Denmark between 2006 and 2017, and followed their vital status for up to 13 years. We computed 1- and 5-year overall survival and hazard ratios (HRs) of death according to comorbidity status using Charlson Comorbidity Index (CCI) among patients aged < 70 years and ≥ 70 years. Results: In all, 36% of the patients had registered comorbidity at the time of diagnosis. Survival decreased with increasing CCI score. It did though increase for all groups of CCI scores (0, 1-2 and 3+) over time. For patients without comorbidity diagnosed in 2006-2008 and 2015-2017, 5-year survival rate increased from 57% to 69%. For patients with a CCI score of 1-2 vs 3, the 5-year survival rate increased from 46% to 62% vs 39% to 44%. In age- and gender-stratified analyses, patients with a CCI score of 1-2 and 3+ had increased mortality compared to patients without registered comorbidity (HR 1.15, 95 % CI 1.06-1.24) and (HR 1.56, 95 % CI 1.40-1.73). Patterns were similar for older (≥70 years) and younger (<70 years) patients. Particularly, diagnoses of congestive heart failure, peripheral vascular and cerebrovascular disease, dementia, chronic pulmonary disease, preexisting renal and liver disease, diabetes and lymphoma led to increased mortality. Conclusions: Comorbidity leads to inferior survival outcomes in patients with renal cell carcinoma, irrespective of age, despite an overall increasing survival. These data may guide patient counseling and prompt initiatives for controlling comorbidity.

Comorbidity and early death in Danish stage I lung cancer patients - an individualised approach

Background: Comorbidity is an important prognostic marker and a treatment indicator for lung cancer patients. Register-based studies often describe the burden of comorbidity by the Charlson comorbidity index (CCI) based on hospital discharge data. We assessed the association between somatic and psychiatric comorbidity and death within one year in early lung cancer and, furthermore, the burden of comorbidity according to treatment type.Material and methods: We conducted a population-based matched case-control study of stage I lung cancer identifying all treated patients who died (all-cause) within one year after diagnosis (early death group, cases). On the basis of data from the Danish Lung Cancer Registry these patients were then matched with two controls who survived more than one year (survivors). Through a review of the medical records, we validated inclusion criteria and collected data on somatic and psychiatric comorbidity. We assessed the association between comorbidity and early death with multivariate conditional logistic regression.Results: We included 221 cases and 410 controls. The mean CCI score in the early death group was 2.3 vs. 1.3 in the survivor group (p < .001). Still, 22% vs. 30% had a CCI score of zero (p = .04) with an average number of comorbidities among these patients of 1.63 vs. 1.06 respectively (p = .006). Among women, 23% in the early death group had depression vs. 13% in the survivor group, corresponding to an unadjusted odds ratio (OR) of 2.0 (CI 95% 1.0-3.7). However, in an adjusted analysis (incl. somatic comorbidities) the OR was 1.7 (CI 95% 0.8-3.5). Patients undergoing oncological therapy were older and tended to have more somatic comorbidities than the surgically treated patients.Conclusion: Comorbidity remains a significant prognostic marker even for stage I lung cancer patients with a CCI score of zero. The suggested association between early death and depression among women needs to be studied further.

Agreement between the Danish Cancer Registry and the Danish Lung Cancer Registry

INTRODUCTION

The Danish Cancer Registry (DCR) and the Danish Lung Cancer Registry (DLCR) are nation-wide registries recording Danish patients with lung cancer (LC). The aim of this study was to assess data agreement and possible consequences hereof on estimation of survival between patients in the two registries.

METHODS

Descriptive statistics were used for comparison of registered patients in 2013-2014 in the DCR and the DLCR. Furthermore, the one-year relative survival (1y-RS) and Cox proportional mortality hazard rates (MRR) were calculated.

RESULTS

In 2013-2014, a total of 9,111 Danish residents were identified with LC in the DCR and 9,316 were found in the DLCR. Merging the two registries showed an agreement of 87%, whereas 6% were included only in the DCR and 8% only in the DLCR. Including patients only registered in one registry, but who seemed to meet the inclusion criteria of both registries, would increase the agreement to 95%. No differences were seen for 1y-RS. However, MRR for patients in the DLCR was significantly lower than for patients in the DCR: 0.94 (95% confidence interval: 0.91-0.98).

CONCLUSIONS

Surprisingly, the DCR registered fewer patients in 2013-2014 than the DLCR, even though they employ the same primary data source. The agreement between the DCR and the DLCR was 87%; this may be increased to 95% if patients who seemed to meet the inclusion criteria of the other register were also included. The discrepancies found were mainly due to different definitions of dates of diagnosis, registrations probably missed by the algorithms and possible registration errors. Discrepancies resulted in a significant difference in MRR, but not in 1y-RS.

FUNDING

none.

TRIAL REGISTRATION

not relevant.

Registrations of Patients with Renal Cell Carcinoma in the Nationwide Danish Renal Cancer Database versus the Danish Cancer Registry: Data Quality, Completeness and Survival (DaRenCa Study-3)

Background

The Danish multidisciplinary renal cancer group (DaRenCa) established the nationwide database DaRenCaData in 2010. The Danish Cancer Registry (DCR) has been considered the golden standard. In contrast to DCR, DaRenCaData required the diagnosis to be histologically or cytologically verified. DaRenCaData and DCR have not previously been compared.

Patients and Methods

We included patients with renal cell carcinoma registered in DaRenCaData and/or DCR from August 1st 2010 to December 31st 2015. We computed completeness and positive predictive value (PPV) of a diagnosis in DaRenCaData compared with DCR, 1-year, 3-year and 5-year mortality rate ratios, and relative survival.

Results

We identified 4890 patients in the two registries. Of these, 4326 were registered in DaRenCaData and 4714 in DCR. Completeness of DaRenCaData was 88% [95% CI, 87–89%] and increased during the period from 82% to 94%. The PPV was 96% [95% CI, 95–97%]. A total of 4150 patients (85%) were found in both registries, 4% (176 patients) in DaRenCaData only, and 12% (564 patients) in DCR only. The relative survival was higher for patients in DaRenCaData vs DCR; the 1-year and 5-year relative survival was 85% vs 81% and 65% vs 59%, respectively. Compared with patients registered in both registries, the mortality rates were higher in patients registered in DaRenCaData only (1-year hazard ratio (HR)=2.84 [95% CI, 2.20–3.68]) or DCR only (1-year HR=4.29 [95% CI, 3.72–4.93]). Observed in both registries, survival improved over time with a 7% yearly reduction in death based on estimations of 1-year mortality rate ratios.

Conclusion

DaRenCaData had high and increasing completeness and high PPV, establishing it as a high-quality research database. Observed in both registries, renal cell carcinoma mortality declined over time; patients only registered in DCR or DaRenCaData had poorer outcomes. This study points to the importance of assessing the inclusion criteria when interpreting registry-based studies.

Does losing a parent early influence the education you obtain? A nationwide cohort study in Denmark

BACKGROUND

Health inequalities are rooted in education and we investigate the association between early parental death and attainment across the educational spectrum.

METHODS

Using total population data on Danes born between 1982 and 2000 (n = 1 043 813), we assess incidence rate ratios (RRs) by gender for attainment of each educational level (basic school, high school or vocational training, bachelor degree or professional programme, and university graduate degree) according to loss of a parent before the age of 18 years. We adjust for family income, education and psychiatric illness and examine parent's gender, cause of death and child's age at time of death as potential moderators.

RESULTS

Bereaved people had significantly lower attainment rates than non-bereaved people: basic school (RR = 0.95; 95% CI: 0.93-0.97 for men and 0.96; 0.94-0.98 for women), high school or vocational training (0.78; 0.76-0.80 for men and 0.82; 0.80-0.84 for women), bachelor degree or professional programme (0.74; 0.70-0.79 for men and 0.83; 0.79-0.86 for women) and university graduate degree (0.77; 0.68-0.86 for men and 0.77; 0.69-0.86 for women). Parent's gender, cause of death and child's age at the death did not modify the associations.

CONCLUSIONS

As education impacts population health, support for bereaved school children may be more important than realized.

OP0068 INCIDENCE AND PREVALENCE OF RHEUMATOID ARTHRITIS IN DENMARK: A NATIONWIDE POPULATION-BASED STUDY INVESTIGATING THE EFFECT OF FOUR DIFFERENT CASE DEFINITIONS

Background:

The incidence rate (IR) and point prevalence (PP) of rheumatoid arthritis (RA) in Denmark is largely unknown. Two challenges in estimating the “true” IR and PP using nationwide registry data are the choice of the RA case definition, and the denominator used, i.e. the exact amount of person years (PY) or census count data.

Objectives:

To investigate the incidence and prevalence of RA in the adult Danish population using four different case definitions and two different denominator strategies.

Methods:

Nationwide register-based cohort study. Patients with RA between 1996 and the end of 2016 were identified using the Danish National Patient Registry (DNPR) and information on DMARD prescriptions were obtained through linkage with the Danish National Prescription Registry. Age and sex standardised incidence and prevalence of RA were calculated in different ways: we estimated the IR (denominator = actual recorded number of PY in each year using migration and vital data) and the incidence proportion (IP) (denominator = census count data); and the PP (%) of RA was calculated for years 2000, 2009, 2011 and 2016. The four case definitions were: Model A, a first time RA diagnosis (ICD-10: M05-06) in DNPR and a redeemed prescription of a conventional DMARD in the following year1; Model B, an RA diagnosis recorded twice in DNPR within 90 days with both records originating from a department of rheumatology or general internal medicine2; Model C, any RA diagnosis recorded in DNPR with a DMARD prescription redeemed in the year before or after the diagnosis; Model D, similar to Model A but with the additional requirement that cases had no registered ICD code for inflammatory diseases prior to the RA diagnosis1.

Results:

The overall IR of RA from 1996 to 2016 based on model A was 35.2 (95%CI 34.8 to 35.6) per 100,000 PY while the IP was 34.7 (95%CI 34.3 to 35.1) per 100,000 individuals. The age standardised IR was higher for women than for men (Figure 1), and this was observed across all age groups. The IR peaked at age 70 to 74 in both men and women. Regardless of which case definition was used, the temporal trend showed a peak in IR in 2010 followed by a plateau (Figure 2). The overall PP estimate for all four models increased from 2000 to 2016, data shown for Model A in Table 1.

Table 1.

Point prevalence (PP) of rheumatoid arthritis in years 2000, 2009, 2011 and 2016 based on Model A

2000N = 590670.3 % women2009N = 1503770.9 % women2011N = 1736371.0 % women2016N = 2299170.3 % womenPP (%) (95% CI)PP (%) (95% CI)PP (%) (95% CI)PP (%) (95% CI)All0.16 (0.15 to 0.16)0.37 (0.36 to 0.37)0.41 (0.41 to 0.42)0.52 (0.51 to 0.52)Women0.21 (0.20 to 0.22)0.50 (0.49 to 0.51)0.57 (0.56 to 0.58)0.71 (0.70 to 0.72)Men0.10 (0.10 to 0.11)0.23 (0.22 to 0.23)0.25 (0.25 to 0.26)0.32 (0.31 to 0.33)

Conclusion:

A peak in the IR of RA was observed in 2010, regardless of which case definition was used. We believe this was due to introduction of the new EULAR/ACR diagnostic criteria at that time. IP estimates were systematically lower than IRs calculated using exact migration and vital data as denominator. The PP increased over time regardless of which case definition we used. We conclude that the choice of RA case definition had a larger influence than the choice of denominator.

References:

[1]inauskas A et al. Positive predictive value of first-time rheumatoid arthritis diagnoses and their serological subtypes in the Danish National Patient Registry. Clin Epidemiol. 2018;10:1709-1720.

[2]Ibfelt E et al. Validity and completeness of rheumatoid arthritis diagnoses in the nationwide DANBIO clinical register and the Danish National Patient Registry. Clin Epidemiol. 2017:627-632.

Acknowledgments:

The study is funded by the Danish Rheumatism Association.

Disclosure of Interests:

Bolette Gylden Soussi: None declared, René Lindholm Cordtz: None declared, Salome Kristensen: None declared, Christian Sørensen Bork: None declared, Jeppe Christensen: None declared, Erik Berg Schmidt: None declared, Daniel Prieto-Alhambra Grant/research support from: Professor Prieto-Alhambra has received research Grants from AMGEN, UCB Biopharma and Les Laboratoires Servier, Consultant of: DPA’s department has received fees for consultancy services from UCB Biopharma, Speakers bureau: DPA’s department has received fees for speaker and advisory board membership services from Amgen, Lene Dreyer: None declared

Agreement between the Danish Cancer Registry and the Danish Colorectal Cancer Group Database

Background: The Danish Cancer Registry (DCR) and the Danish Colorectal Cancer Group (DCCG) database are population-based registries collecting information on Danish patients with colorectal cancer (CRC). DCR registers all patients with incident CRC whereas DCCG records patients with first time CRC. The registries use different inclusion criteria. The consequencenses of this are unknown and not previously evaluated. The aim of this study was to examine the agreement between patients registered in DCR and DCCG and to evaluate its influence on estimated survival and mortality.Material and methods: Patients registered in DCR and DCCG with CRC in 2014-2015 were included. Because of different inclusion criteria, DCCG's inclusion criteria were applied to DCR. Descriptive statistics were used for comparisons. One-year relative survival (1-year RS) was calculated, and the Cox proportional hazard model used for calculating 1-year mortality rate ratios (1-year MRR).Results: In 2014-2015, DCR registered 9678 Danish residents with CRC that fulfilled DCCG's inclusion criteria, while DCCG registered 10,312 Danish residents with CRC. Allowing ±180 days between dates of diagnosis, 10,688 patients were registered with CRC in the merger of the two registries. Of these, 86% were included in both registers, 4% only in DCR, and 10% only in DCCG. No difference was found in 1-year RS between patients in DCR 86% (95% CI: 85-87) and DCCG 85% (95% CI: 84-86). However, patients registered in DCCG had a 1-year MRR of 1.09 (95% CI: 1.01-1.17) compared to DCR.Conclusion: An agreement of 86% of patients was found between the two registries. The discrepancy did not influence 1-year RS. DCCG registered more patients than DCR, and 1-year MRR of patients in DCCG was increased compared to patients in DCR. Regular linkage of the registries is recommended to improve data quality of both registries.

Nationwide cohort study of the impact of education, income and social isolation on survival after acute colorectal cancer surgery

Background

Acute colorectal cancer surgery has been associated with a high postoperative mortality. The primary aim of this study was to examine the association between socioeconomic position and the likelihood of undergoing acute versus elective colorectal cancer surgery. A secondary aim was to determine 1‐year survival among patients treated with acute surgery.

Methods

All patients who had undergone a surgical procedure according to the Danish Colorectal Cancer Group (DCCG.dk) database, or who were registered with stent or diverting stoma in the National Patient Register from 2007 to 2015, were reviewed. Socioeconomic position was determined by highest attained educational level, income, urbanicity and cohabitation status, obtained from administrative registries. Co‐variables included age, sex, year of surgery, Charlson Co‐morbidity Index score, smoking status, alcohol consumption, BMI, stage and tumour localization. Logistic regression analysis was performed to determine the likelihood of acute colorectal cancer surgery, and Kaplan–Meier and Cox proportional hazards regression methods were used for analysis of 1‐year overall survival.

Results

In total, 35 661 patients were included; 5310 (14·9 per cent) had acute surgery. Short and medium education in patients younger than 65 years (odds ratio (OR) 1·58, 95 per cent c.i. 1·32 to 1·91, and OR 1·34, 1·15 to 1·55 respectively), low income (OR 1·12, 1·01 to 1·24) and living alone (OR 1·35, 1·26 to 1·46) were associated with acute surgery. Overall, 40·7 per cent of patients died within 1 year of surgery. Short education (hazard ratio (HR) 1·18, 95 per cent c.i. 1·03 to 1·36), low income (HR 1·16, 1·01 to 1·34) and living alone (HR 1·25, 1·13 to 1·38) were associated with reduced 1‐year survival after acute surgery.

Conclusion

Low socioeconomic position was associated with an increased likelihood of undergoing acute colorectal cancer surgery, and with reduced 1‐year overall survival after acute surgery.

Tau positron emission tomography imaging in C9orf72 repeat expansion carriers

BACKGROUND AND PURPOSE

AV-1451 (18 F-AV-1451, flortaucipir) positron emission tomography was performed in C9orf72 expansion carriers to assess tau accumulation and disease manifestation.

METHODS

Nine clinically characterized C9orf72 expansion carriers and 18 age- and gender- matched cognitively normal individuals were psychometrically evaluated and underwent tau positron emission tomography imaging. The regional AV-1451 standard uptake value ratios from multiple brain regions were analyzed. Spearman correlation was performed to relate the AV-1451 standard uptake value ratio to clinical, psychometric and cerebrospinal fluid measures.

RESULTS

C9orf72 expansion carriers had increased AV-1451 binding in the entorhinal cortex compared to controls. Primary age-related tauopathy was observed postmortem in one patient. AV-1451 uptake did not correlate with clinical severity, disease duration, psychometric performance or cerebrospinal fluid markers.

CONCLUSION

C9orf72 expansion carriers exhibited increased AV-1451 uptake in entorhinal cortex compared to cognitively normal controls, suggesting a propensity for primary age-related tauopathy. However, AV-1451 accumulation was not associated with psychometric performance in our cohort.

Do people improve health behavior after their partner is diagnosed with cancer? A prospective study in the Danish diet, Cancer and Health Cohort

Background: The cancer diagnosis is regarded as a stressful life event that is thought to trigger a teachable moment to induce health behavior changes among cancer patients. However, this may also hold true for their partners. We assessed if partners of cancer patients make more health behavior changes compared to persons whose partner remained cancer-free. Methods: Lifestyles was assessed in the prospective Danish Diet, Cancer and Health study. Logistic regression analyses were used to assess health behavior change among partners of cancer patients (n = 672) compared to partners of persons who remained cancer-free (n = 5534). Additionally, associations in two subgroups were assessed: bereaved partners and partners of patients who remained alive after cancer. Results: Partners of cancer patients were more likely to decrease their alcohol intake compared to partners of persons who remained cancer free. This finding could mainly be attributed to bereaved partners. Moreover, bereaved partners were also more likely to decrease their BMI. In contrast to our hypothesis, bereaved partners were more likely to decrease fruit intake and increase sugared beverages compared to partners of persons who remained cancer free. In general, men tended to improve their physical activity, while women tended to worsen their physical activity following the cancer diagnosis of their partner. Conclusions: A cancer diagnosis in the partner does seem to improve health behavior change only for alcohol intake. Bereaved partners tend to worsen dietary behaviors after the patient's death.

Mortality after emergency treatment of colorectal cancer and associated risk factors-a nationwide cohort study

PURPOSE

The aim of this study was to investigate if postoperative mortality after acute surgical treatment of colorectal cancer has decreased in Denmark during this period and to investigate risk factors associated with early death.

METHODS

This is a nationwide and population-based cohort study. From the Danish Colorectal Cancer Group database and National Patient Registry, we collected data on all patients operated with bowel resection, diverting stoma only, or placement of an endoscopic stent from 2005 to 2015. Year of surgery was the main exposure variable and 90-day postoperative mortality the primary outcome.

RESULTS

We included 6147 patients. The incidence of patients per year was stable during 2005-2015. The 90-day mortality decreased from 31% in 2005 to 24% in 2015 with a significant time trend (p < 0.0001). Other factors associated with postoperative mortality were increasing age, presence of comorbidity (measured as Charlson comorbidity index score ≥ 1), and stage IV disease. Insertion of self-expanding metallic stent was protective for 90-day postoperative mortality compared with other surgical procedures.

CONCLUSION

Ninety-day postoperative mortality from acute colorectal surgery has improved in Denmark from 2005 to 2015. Nevertheless, almost one out of four patients undergoing acute surgery for colorectal cancer dies within 90 days.

Surgical treatment and survival from colorectal cancer in Denmark, England, Norway, and Sweden: a population-based study

BACKGROUND

Survival from colorectal cancer has been shown to be lower in Denmark and England than in comparable high-income countries. We used data from national colorectal cancer registries to assess whether differences in the proportion of patients receiving resectional surgery could contribute to international differences in colorectal cancer survival.

METHODS

In this population-based study, we collected data from all patients aged 18-99 years diagnosed with primary, invasive, colorectal adenocarcinoma from Jan 1, 2010, to Dec 31, 2012, in Denmark, England, Norway, and Sweden, from national colorectal cancer registries. We estimated age-standardised net survival using multivariable modelling, and we compared the proportion of patients receiving resectional surgery by stage and age. We used logistic regression to predict the resectional surgery status patients would have had if they had been treated as in the best performing country, given their individual characteristics.

FINDINGS

We extracted registry data for 139 457 adult patients with invasive colorectal adenocarcinoma: 12 958 patients in Denmark, 97 466 in England, 11 450 in Norway, and 17 583 in Sweden. 3-year colon cancer survival was lower in England (63·9%, 95% CI 63·5-64·3) and Denmark (65·7%, 64·7-66·8) than in Norway (69·5%, 68·4-70·5) and Sweden (72·1%, 71·2-73·0). Rectal cancer survival was lower in England (69·7%, 69·1-70·3) than in the other three countries (Denmark 72·5%, 71·1-74·0; Sweden 74·1%, 72·7-75·4; and Norway 75·0%, 73·1-76·8). We found no significant differences in survival for patients with stage I disease in any of the four countries. 3-year survival after stage II or III rectal cancer and stage IV colon cancer was consistently lower in England (stage II rectal cancer 86·4%, 95% CI 85·0-87·6; stage III rectal cancer 75·5%, 74·2-76·7; and stage IV colon cancer 20·5%, 19·9-21·1) than in Norway (94·1%, 91·5-96·0; 83·4%, 80·1-86·1; and 33·0%, 31·0-35·1) and Sweden (92·9%, 90·8-94·6; 80·6%, 78·2-82·7; and 23·7%, 22·0-25·3). 3-year survival after stage II rectal cancer and stage IV colon cancer was also lower in England than in Denmark (stage II rectal cancer 91·2%, 88·8-93·1; and stage IV colon cancer 23·5%, 21·9-25·1). The total proportion of patients treated with resectional surgery ranged from 47 803 (68·4%) of 69 867 patients in England to 9582 (81·3%) of 11 786 in Sweden for colon cancer, and from 16 544 (59·9%) of 27 599 in England to 4106 (70·8%) of 5797 in Sweden for rectal cancer. This range was widest for patients older than 75 years (colon cancer 19 078 [59·7%] of 31 946 patients in England to 4429 [80·9%] of 5474 in Sweden; rectal cancer 4663 [45·7%] of 10 195 in England to 1342 [61·9%] of 2169 in Sweden), and the proportion of patients treated with resectional surgery was consistently lowest in England. The age gradient of the decline in the proportion of patients treated with resectional surgery was steeper in England than in the other three countries in all stage categories. In the hypothetical scenario where all patients were treated as in Sweden, given their age, sex, and disease stage, the largest increase in resectional surgery would be for patients with stage III rectal cancer in England (increasing from 70·3% to 88·2%).

INTERPRETATION

Survival from colon cancer and rectal cancer in England and colon cancer in Denmark was lower than in Norway and Sweden. Survival paralleled the relative provision of resectional surgery in these countries. Differences in patient selection for surgery, especially in patients older than 75 years or individuals with advanced disease, might partly explain these differences in international colorectal cancer survival.

FUNDING

Early Diagnosis Policy Research Grant from Cancer Research UK (C7923/A18348).

Assessing the pattern of recurrence in Danish stage I lung cancer patients in relation to the follow-up program: are we failing to identify patients with cerebral recurrence?

BACKGROUND

There is paucity of evidence regarding the optimal follow-up (FU) regimen for lung cancer. Consequently, FU is organized differently across countries. The Danish FU regimen has short FU intervals with a computed tomography (CT) scan of the chest and upper abdomen every three months in the early phase (first 2 years), then every six months in the late phase of FU (3rd, 5th year). Characterizing recurrences missed by the FU program in terms of site, tumor histology, department, and phase of FU, could improve the FU program.

MATERIAL AND METHOD

A case-control study of curatively treated stage I lung cancer patients who attended the Danish FU-program and had recurrence identified through the follow-up program (controls, FU group) or outside FU program (cases, symptomatic group).

RESULTS

Of 233 included patients with recurrence, the FU group constituted 85% (n = 197). Among the 15% (n = 36) in the symptomatic group, 53% had involvement of the central nervous system compared with 3% in the FU group. The unadjusted odds ratio (OR) for having an isolated brain recurrence (IBR) in the symptomatic group was 52.3 (95%CI: 15.1-181.4) as compared with the FU group. The OR for having a symptomatic recurrence in the early phase of FU was 2.5 (95%CI: 0.7-8.7) compared with the late phase.

CONCLUSIONS

The FU program did not identify the majority of patients with IBR. Including cerebral imaging in the FU program may result in an earlier detection of brain metastases. These matters should be studied in a prospective setting.

Treatment and Survival From Colorectal Cancer in Denmark, England, Norway, and Sweden: A Population-Based Study

Background: Colorectal cancer (CRC) patients in Denmark and England have historically had worse outcomes than patients diagnosed in other high-income countries with similar healthcare coverage. This survival deficit may be partly explained by differences in stage distribution due to delays in cancer diagnosis, however, differences in stage-specific survival suggest that differences in treatment also explain the survival gap. Aim: We aim to provide a comparison of stage-specific survival of CRC patients diagnosed in Denmark, England, Norway and Sweden, and compare the probability of receiving potentially curative surgery (PCS) by patient and tumor characteristics to understand whether differences in stage and treatment help explain the international differences in survival. Methods: Population-based information on patients aged 18-99 years diagnosed with primary malignant colon or rectal cancer in Denmark, England, Norway, and Sweden during 2010-2012 was extracted from national CRC registries. We compared the prevalence of PCS by stage and age category, and estimated the probability of receiving it using multivariate logistic regression. Age-standardized net survival was estimated using a multivariable modeling approach. Results: There were 13,230 patients diagnosed with CRC in Denmark, 99,869 in England, 11,754 in Norway, and 17,584 in Sweden between 2010 and 2012. The proportion of patients with missing stage information was higher in England than in the other countries. Stage distribution was otherwise similar. Survival of patients with stage I-II tumors was generally comparable between the countries, but lower in England and - to a lesser degree - in Denmark for stage III-IV disease. Patients with unknown stage had lower survival than staged patients in all countries. We found marked disadvantages in the probability of receiving PCS in older patients with stage II-IV disease in England, and stage IV colon cancer patients in Denmark. The proportion of surgically-treated rectal cancer patients (and their survival) was comparable between Denmark, Norway and Sweden for each combination of age group and stage, except for patients diagnosed with stage I disease. The proportion of patients receiving surgery and survival from rectal cancer was generally lower in England. Conclusion: Denmark seems to be catching up with Norway and Sweden, especially in rectal cancer survival. Despite recent improvements, CRC survival in England remains lower than in Sweden and Norway. Survival generally paralleled countries' relative performance in the provision of potentially curative surgery. Differences in patient selection for surgery, especially in older patients and/or with advanced disease, may partly explain the survival deficit. Increases in the proportion treated, in combination with efforts in postoperative care and with other treatment modalities, may translate into better longer-term outcomes, especially for frail patients.

Valley Physics in Non-Hermitian Artificial Acoustic Boron Nitride

The valley can serve as a new degree of freedom in the manipulation of particles or waves in condensed matter physics, whereas systems containing combinations of gain and loss elements constitute rich building units that can mimic non-Hermitian properties. By introducing gain and loss in artificial acoustic boron nitride, we show that the acoustic valley states and the valley-projected edge states display exotic behaviors in that they sustain either attenuated or amplified wave propagation. Our findings show how non-Hermiticity introduces a mechanism in tuning topological protected valley transports, which may have significance in advanced wave control for sensing and communication applications.

Impact of egg disinfection of hatching eggs on the eggshell microbiome and bacterial load

Disinfection of hatching eggs is essential to ensure high quality production of broilers. Different protocols are followed in different hatcheries; however, only limited scientific evidence on how the disinfection procedures impact the microbiome is available. The aim of the present study was to characterize the microbiome and aerobic bacterial load of hatching eggs before disinfection and during the subsequent disinfection steps. The study included a group of visibly clean and a group of visibly dirty eggs. For dirty eggs, an initial wash in chlorine was performed, hereafter all eggs were submitted to two times fumigation and finally spray disinfection. The eggshell microbiome was characterized by sequencing of the total amount of 16S rRNA extracted from each sample, consisting of shell surface swabs of five eggs from the same group. In addition, the number of colony forming units (cfu) under aerobic conditions was established for each disinfection step. The disinfection procedure reduced the bacterial load from more than 104 cfu (initially visibly clean eggs) and 105 cfu (initially visibly dirty eggs) to less than 10 cfu per sample after disinfection for both groups of eggs. The microbiome of both initially visibly clean and initially visibly dirty eggs had the highest abundances of the phyla Firmicutes, Proteobacteria and Bacteroidetes. Within the phyla Firmicutes the relative abundances of Clostridiales decreased while Lactobacillus increased from before to after final disinfection. In conclusion, the investigated disinfection procedure is effective in reducing the bacterial load, and by adding a chlorine wash for initially visibly dirty eggs, the microbiome of initially visibly clean and initially visibly dirty eggs had a highly similar microflora after the final disinfection step.

Early parental loss and intimate relationships in adulthood: A nationwide study

Being able to form and maintain intimate relationships is an essential part of development and the early loss of a parent may negatively affect this ability. This study investigates the association between parental loss before the age of 18 years and the formation and dissolution of marriage and cohabitation relationships in adulthood, in relation to factors that may help identify potentially vulnerable subgroups of bereaved children, that is, sex of the deceased parent, cause of death and child's age at the time of death. Using data from national registries, we followed all children born in Denmark between 1970 and 1995 (n = 1,525,173) and used Poisson regression models to assess rate ratios by gender for relationship formation and separation according to early parental loss. We stratified the analyses by sex of the deceased parent, cause of death and child's age at the time of death, and adjusted for the confounding effects of parental income, education level, and psychiatric illness. We found that parental loss was associated with a higher rate of relationship formation for young women, but not young men, and higher rates of separation for both men and women. The associations with separation were stronger for persons who lost a parent to suicide than to other causes. The effects were relatively small, a possible testimony to the resilience of developmental processes in most children. However, as long-term relationships are associated with physical and psychological health, interventions for bereaved children and families are important, especially in the subgroup bereaved by suicide. (PsycINFO Database Record