Healthcare Burden in Greenland of Gastrointestinal Symptoms in Adults with Inherited Loss of Sucrase-Isomaltase Function

Background

Congenital sucrase isomaltase deficiency (CSID) is in general a very rare disease. However, 2-3% of the Greenlandic population are homozygous (HO) carriers of an Arctic-specific loss-of-function (LoF) variant in the sucrase-isomaltase (SI) encoding gene, causing CSID. The condition is characterized by gastrointestinal symptoms such as stomachache, diarrhea, and weight loss when consuming sucrose, the most common dietary sugar. However, the awareness of the condition in the population and the healthcare system seems to be limited, potentially leading to a higher healthcare burden. Hence, we aimed to investigate whether HO-carriers visit the healthcare system more with gastrointestinal symptoms compared to the control groups by using registry data.

Methods

We performed a case-control study identifying cases and controls using genotype information from the 1999-2001 and 2005-2010 Greenlandic health population cohorts. The cases were defined as HO LoF SI-carriers and controls were defined as non-carriers and were matched (1:1) on sex, age, place of residence, and European genetic admixture. We used electronic medical records to assess the number of electronic medical record contacts (EMRc) related to gastrointestinal symptoms and the number of gastrointestinal-related diagnostic procedures.

Results

A total of 80 HO-carriers and 80 non-carriers were included. The HO-carriers had 19% more EMRc related to gastrointestinal symptoms (IRR, 1.19, 95% CI [1.02;1.40], p=0.02) and had a 41% higher incidence of gastrointestinal related diagnostic procedures compared to controls (IRR, 1.41, 95% CI [1.05-1.92], p=0.02). Only one HO-carrier was aware of the condition according to the electronic medical records.

Conclusion

HO-carriers of the LoF SI-variant had both significantly more gastrointestinal-related EMRc and significantly more diagnostic procedures conducted due to gastrointestinal symptoms. Only one HO-carrier was aware of the condition. Given the high prevalence of HO-carriers in the Greenlandic population, we anticipate that diagnosing more patients with CSID and providing dietary advice could potentially reduce symptom burden and healthcare visits among HO-carriers.

The effect of sucrase-isomaltase deficiency on metabolism, food intake and preferences: protocol for a dietary intervention study

In Greenland, traditional marine foods are increasingly being replaced by sucrose- and starch-rich foods. A knock-out c.273_274delAG variant in the sucrase-isomaltase (SI) gene is relatively common in Greenland, with homozygous carriers being unable to digest sucrose and some starch. The variant is associated with a healthier metabolic phenotype in Greenlanders, which is confirmed by SI-knockout mice. We aim to assess if the healthy phenotype is explained by metabolic and microbial differences and if food and taste preferences differ between SI-genotypes. This paper describes the protocol for a randomised cross-over trial conducted in Greenland in 2022 with two dietary interventions of three days; a traditional meat- and fish-rich diet and a starch-rich Western diet with 11 energy% sucrose. The power calculation showed that 22 homozygous SI-carriers and 22 non-carriers were sufficient to detect a 0.5 mmol/L difference in glycaemic variability (80% power, α=0.05). We enrolled 18 carriers and 20 non-carriers. We examined food preferences at baseline and collected samples before and after each intervention for metabolic, metabolome, and microbiome profiling. Analyses of samples have not been completed yet. The Ethics Committee of Greenland approved the study. Results will be disseminated in international peer-reviewed journals and to the general Greenlandic population. NCT05375656.

Sleep is required to consolidate odor memory and remodel olfactory synapses

Animals with complex nervous systems demand sleep for memory consolidation and synaptic remodeling. Here, we show that, although the Caenorhabditis elegans nervous system has a limited number of neurons, sleep is necessary for both processes. In addition, it is unclear if, in any system, sleep collaborates with experience to alter synapses between specific neurons and whether this ultimately affects behavior. C. elegans neurons have defined connections and well-described contributions to behavior. We show that spaced odor-training and post-training sleep induce long-term memory. Memory consolidation, but not acquisition, requires a pair of interneurons, the AIYs, which play a role in odor-seeking behavior. In worms that consolidate memory, both sleep and odor conditioning are required to diminish inhibitory synaptic connections between the AWC chemosensory neurons and the AIYs. Thus, we demonstrate in a living organism that sleep is required for events immediately after training that drive memory consolidation and alter synaptic structures.

Dyslipidemia and the preventive potential in the Greenlandic population

Background

Low-density lipoprotein cholesterol (LDL-C) is a well-established risk factor for development of cardiovascular diseases. Based on available clinical data, we aimed to investigate the plasma lipid profile in the Greenlandic population, the proportion on cholesterol-lowering treatment and the adherence to local indications for cholesterol-lowering therapy.

Methods

This is an observational cross-sectional study of the adult (≥21 years) Greenlandic population with focus on clinically determined lipid levels from 2017 to early 2022. We investigated levels of dyslipidemia and assessed cholesterol-lowering medication usage in individuals with an indication according to current Greenlandic guidelines, which include a) LDL-C >5 mmol/l, b) diabetes, c) diagnosed atherosclerotic disease and 4) a SCORE2 >7.5%.

Results

In the adult Greenlandic population of 40,565 individuals a lipid profile was available in 13,895 with a mean LDL-C of 3.0 mmol/L and 976 (7%) had a LDL-C >5 mmol/l. One or more indications for cholesterol-lowering medication was present in 3988 individuals and a total of 5464 adult Greenlanders either fulfilled local criteria for statin therapy or received a statin (some without current indication) and among these, 2232 (41%) individuals received no statin.

Conclusion

These findings indicate that clinically significant dyslipidemia is common in the adult Greenlandic population and that the cardiovascular preventive potential of cholesterol-lowering therapy is currently underutilized.

Long-term incidence of pacemaker implantations and bradycardia among cross-country skiers

Background

Bradycardia is more common among well-trained athletes. The associations of training with pacemaker implantations are less known. We aim to investigate the association of endurance training with incidence of bradycardia and pacemaker implantations in a cohort of endurance athletes. Furthermore, we aim to establish potential sex differences of such associations.

Methods

Swedish skiers (209,072) that completed 1 or more races in the 30 to 90 km cross-country skiing event Vasaloppet (1989–2011) and a matched sample (n=531,949) of nonskiers were followed until first event of bradycardia or pacemaker implantation. The Swedish National Patient Register of in-patient and specialized outpatient care was used to obtain the date of diagnoses. Cox regression was used to investigate associations of number of completed races and finishing time with incidence of bradycardia and pacemaker implantations.

Results

Male skiers had higher incidence of bradycardia (hazard ratio [HR], 1.14; 95% CI, 0.99–1.30) and pacemaker implantations (HR, 1.14; 95% CI, 1.02–1.28) than male nonskiers. Male skiers completing most races or with the fastest finishing times had the highest incidence. The incidence of bradycardia (HR, 0.96; 95% CI, 0.70–1.30) and pacemaker implantations (HR, 0.97; 95% CI, 0.75–1.25) among female skiers in Vasaloppet was not different to that of female nonskiers. There was a trend that female skiers completing most races or with fastest finishing times had lower incidence.

Conclusions

Male skiers had higher incidence of bradycardia and pacemaker implantations. Female skiers in Vasaloppet had non-different incidence of bradycardia and pacemaker implantations. Men with the highest number of races and fastest finishing times had the highest incidence of pacemaker implantations. This indicates that bradycardia associated with training is not always as benign as previously suggested. The response appears to be different between sexes.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Uppsala UniversityCKF Dalarna

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Hospitalization time is associated with weight gain in forensic mental health patients

Introduction

Previous studies have found substantial weight gains in forensic mental health patients (FMHP) during hospitalisation. However, previous studies have not compared in- and outpatients, thus the weight change could be a general change over time. Research on the association between proportional hospitalization time (PHT) and weight change is lacking.

Objectives

To investigate the association between time hospitalized and weight change among FMHP.

Methods

Retrospective cohort study including FMHP with schizophrenia or bipolar disorder treated in the Region of Southern Denmark between 01jan2016 and 06apr2020. Patient characteristics and data on body weight was extracted from electronic medical records. The association between PHT and weight change per year was analyzed using linear regression. PHT was determined between each measurement as the total number of days hospitalized divided by the total number of days. Analyses were adjusted for gender, age, smoking, and antipsychotic medication.

Results

The cohort included 328 FMHP, of which 91% were diagnosed with schizophrenia. PHT had a significant positive dose-response association with weight change, with an estimated difference of +4.0 kg/year for FMHP who were hospitalized 100% of the time, compared to FMHP who were exclusively treated as outpatients. The associations were different for FMHP belonging to different categories of BMI at baseline (test for interaction; p=0.006). Underweight hospitalized FMHP had the largest difference in weight gain compared to FMHP treated outside hospitals (+18.0 kg/year, p=0.006), and the difference was smallest in obese FMHP (+2.3 kg/year, p=0.21).

Conclusions

PHT was positively associated with weight change among FMHP.

Disclosure

No significant relationships.

Gender differences in a clinical sample of 60+ year old patients receiving treatment for alcohol use disorder

Introduction

Gender differences have been found in treatment-seeking older adults with AUD, concerning areas such as quality of life, drinking patterns, and prevalence of AUD. However, little is known about how these gender differences may relate to treatment.

Objectives

To investigate gender differences in quality of life, problematic areas at treatment start, and subsequent choice of treatment, in a clinical sample of 60+ year old patients receiving treatment for AUD.

Methods

We will utilize data from the Elderly Study; a multi-national (USA, Germany, and Denmark), single-blind randomized controlled trial. Participants (n=693) were randomized to brief, outpatient treatment based on motivational enhancement therapy alone (4 sessions) or motivational enhancement therapy followed by a community reinforcement approach age-adapted to older adults (up to 8 sessions). The latter was a module-based treatment where participants chose which module(s) they deemed most relevant. Modules focused on coping with aging, building sober networks, mood management, etc. The gender differences at baseline will be described by means of descriptive statistics (e.g. one-way analysis of variance, χ2 statistics, etc.). Gender differences, including choice of modules, will be investigated by means of multivariate statistics, e.g. generalized linear models. Analyses will be controlled for relevant confounders such as age, country, education, work situation, marital status, family and friends, type of housing, etc.

Results

Will be presented at the EPA Congress.

Conclusions

Will be presented at the EPA Congress.

Disclosure

No significant relationships.

Homebased screening for cognitive impairment due to dementia

Introduction

Dementia develops slowly and insidiously and causes cognitive impairment. The diagnosis is pivotal for relevant treatment and care. However, 50,000 people are estimated to have undiagnosed dementia in Denmark, while 36,000 are diagnosed.

The municipalities offers a home visit to the population at the ages of 75 and 80 years to assess the need of care and prevent sickness. These home visits are well established and might offer an unused opportunity to detect cognitive impairment and dementia.

Objectives

To assess impaired cognition at home visits in order to initiate clinical examination for dementia.

Methods

A feasibility study with the use of Brief Assessment of Impaired Cognition Questionnaire (BASIC-Q) (sensitivity 0.92, specificity 0.97) at home visits. It is expected to include 1000 participants without a dementia diagnosis at the ages of 75 and 80 years. Participants will be included in a period of 12 moths (in the year of 2022), in a number of municipalities.

If the screening for cognitive impairment is positive, the participant is motivated for clinical examination at the general practitioner. Follow-up through registers and general practitioners.

Results

Preliminary results will be presented at the conference.

Conclusions

Assessment of cognition might give an opportunity to start medication and social support early in the elderly with impaired cognition and undiagnosed dementia.

Disclosure

No significant relationships.

OP0067 MORE THAN SIX-FOLD INCREASED MORTALITY RISK IN PATIENTS WITH INCIDENT RHEUMATOID ARTHRITIS AND DEPRESSION IN A LARGE COHORT WITH 10-YEAR FOLLOW-UP

Background

The occurrence of depression is increased in patients with rheumatoid arthritis (RA) compared with the background population. (1) Recently, we described that in RA the most frequent indication for filling antidepressant prescriptions is depression and the frequency of filling coincides with the occurrence of depression reported in the scientific literature. (2) In patients with stroke, depression defined as filling of antidepressants or a diagnosis with depression is associated with increased mortality risk and the risk is similar for both definitions of depression. (3)

Objectives

We used the first filling of antidepressants as proxy for depression with the objective to describe the mortality risk associated with depression in patients with incident RA.

Methods

We included patients diagnosed with incident RA (index date) from the nationwide DANBIO register (4) from January 1, 2008 to September 30, 2018. Participants were identified by unique personal registration numbers. Included patients were without a recorded filling of methotrexate (Anatomic Therapeutic Chemical code L01BA01) and antidepressants (N06A) in the Danish National Prescription Register or recorded hospital contacts with RA and depression (International Classification of Diseases (version 10) codes M05, M06, F32) in the Danish National Patient Register, three years prior to the index date. From the index date, we defined depression as first filling of antidepressants and collected death dates from the Danish Civil Registration System. The participants were followed until December 31, 2018 and all-cause mortality estimated in two dynamic risk periods: the period from the index date until first filling of antidepressants (if it occurred) and the period after filling of antidepressants. We calculated hazard rate ratios (HRR) by modelling filling of antidepressants as time-varying exposure for total follow-up and adjusted for potential confounders defined a priori: age, sex, comorbidity, cohabitation, employment status, highest attained education, and income. Cumulative mortality was described by Kaplan-Meier curves. Results were reported with 95% confidence intervals (CI).

Results

Among 11,071 RA patients followed for 56,993 person-years, 1,095 (10%) filled prescriptions for antidepressants. The median age at diagnosis was 61 years, 66% were female, and 64% diagnosed with seropositive RA. Adjusted HRR was highest in the age group <55 years but also increased between 55-70 years, >70 years, among females and males, and in patients diagnosed with seropositive and seronegative RA (Table 1). The cumulative mortality is seen in Figure 1.

Table 1.StrataHRR (95% CI)CrudeAdjustedAge, years<558.40 (4.20-16.80)6.66 (2.80-15.85)55-703.27 (2.35-4.54)3.30 (2.27-4.80)>702.97 (2.36-3.75)2.94 (2.26-3.83)SexFemale3.72 (2.95-4.70)2.91 (2.22-3.81)Male3.10 (2.32-4.15)3.70 (2.66-5.14)RA diagnosisSeropostive (M05)3.73 (2.99-4.65)3.45 (2.66-4.47)Seronegative (M06)2.85 (2.07-3.91)3.08 (2.17-4.37)Figure 1.

Conclusion

Depression, defined as first filling of antidepressants, was associated with more than six-fold increased mortality risk in patients with incident RA.

References

[1]Matcham F, et al. The prevalence of depression in rheumatoid arthritis: A systematic review and meta-analysis. Rheumatology 2013;52:2136-48.

[2]Pedersen JK, et al. No difference in antidepressant prescription in rheumatoid arthritis and controls. Results from a population-based, matched inception cohort. Scand J Rheumatol. 2021; Jun 29:1-7.

[3]Jørgensen TSH, et al. Incidence of depression after stroke, and associated risk factors and mortality outcomes, in a large cohort of Danish patients. JAMA Psychiatry 2016;73:1032-1040.

[4]Ibfelt EH, et al. The Danish nationwide clinical register for patients with rheumatoid arthritis: DANBIO. Clin Epidemiol 2016;8:737-42.

Acknowledgements

The study was supported by the Danish Rheumatism Association.

Disclosure of Interests

None declared.

No difference in antidepressant prescription in rheumatoid arthritis and controls. Results from a population-based, matched inception cohort

Objective: Depression occurs at least two times more often in rheumatoid arthritis (RA) patients than in controls, but little is known about the treatment of depression in RA. The primary objective of this study was to compare the 1 year period prevalence of antidepressant prescription in patients with RA versus controls.Method: We included a retrospective inception cohort of 509 patients with incident RA and 2545 frequency-matched population controls ascertained from 1995 to 2002. The cohort was followed until 31 December 2017 and linked with nationwide Danish registers. From the Danish National Prescription Register, we obtained information on redeemed prescriptions of antidepressants (Anatomical Therapeutic Chemical code N06A).Results: We did not demonstrate significant differences in the 1 year period prevalence ratios and the incidence rate ratios for either antidepressant prescription or the frequency of hospital admissions with depressive episode. The most frequent indication for antidepressant prescription in patients with RA was depression. Cox regression analyses showed no association between RA and antidepressant prescription.Conclusion: We found no significant differences in the occurrence of antidepressant prescription in patients with RA versus matched controls. The main indication for antidepressant prescription in RA was depression.

Percutaneous tibial nerve stimulation for idiopathic and neurogenic overactive bladder dysfunction: a four-year follow-up single-centre experience

OBJECTIVE

Overactive bladder (OAB) affects hundreds of millions of people worldwide and has significant detrimental effects on quality-of-life. Percutaneous tibial nerve stimulation (PTNS) is endorsed in the European guidelines of Urology as second-line therapy - on par with pharmacological treatment for women with OAB.

METHODS

This prospective cohort study describes our clinical experience with PTNS in a daily outpatient clinic, on a consecutive cohort. The cohort of 116 patients was mixed; including both men and women with idiopathic (iOAB) and neurogenic (nOAB) overactive bladder. Patients were treated with a 12-week course of PTNS followed by monthly maintenance treatment. Data were collected during 4 years.

RESULTS

The most common indication for PTNS was OAB with urge incontinence (53%) followed by OAB-dry and nocturia (both 16%). One hundred and ten (95%) patients completed follow-up and 68 patients (62%) continued to maintenance treatment. A total of 68 patients reported an effect on PROM, BD and ICIQ-OAB, which is the same 62% that continue in maintenance PTNS. A significant decline was seen in overall ICIQ-OAB score, with a median drop from 87 to 54, a significant decline in overall frequency and nocturia on bladder diary and a shift in pad test group in 19% of the incontinence patients.

CONCLUSION

PTNS shows an equally significant effect on men as well as women both in the iOAB and nOAB subgroups in a daily outpatient clinic. In our opinion, PTNS should be a standard treatment option available at urological departments, where both men and women in both sub-groups could benefit from treatment. Further randomized studies focusing on men with iOAB are needed.

Risk of aortic disease in long-distance cross-country skiers; a study of 209,226 patients

Background/Introduction

Aneurysmal dilatation and dissection of the aorta are two facets of aortic disease that can lead to major disability and death. Some risk factors for aortic disease are also risk factors for atherosclerotic disease, but the overall causes of aortic disease are diverse and largely unknown. Persons with aortic aneurysms are advised to limit their physical activity, but associations of physical activity with subsequent incidence of aortic disease are little known. Earlier studies have shown strong association of performance in Vasaloppet with incidence of hypertension, a major risk factor for aortic disease.

Aim

To investigate associations of high levels of physical activity with incidence of aortic disease.

Methods

We studied 209,226 participants in a 30–90 km cross-country skiing event (Vasaloppet) and 536,038 persons from the general population, matched to the skiers on age, sex and residence. The number of completed races during the study period and the fastest relative finishing time in a race was recorded. The main outcomes were: 1) aortic disease (defined as thoracic and abdominal aortic aneurysm and/or aortic dissection); and 2) aortic dissection.

Results

During a median time at risk of 8.8 years, 1,442 aortic disease events and 265 aortic dissections occurred. Skiers had lower incidence of aortic disease than non-skiers (Cox proportional hazards ratio [HR] 0.42; 95% confidence interval [CI] 0.36–0.50). An association of better finishing time with aortic disease was observed, with a dose-response gradient from the fastest third (HR 0.25; 95% CI 0.18–0.35), via the slowest third (HR 0.64; 95% CI 0.49–0.82) to the non-skiers (reference group). Among skiers the number of completed races was not associated with incidence of aortic disease. Skiers also had lower incidence of acute aortic dissection (HR 0.61; 95% CI 0.44–0.85) than non-skiers. Low event rate among skiers made conclusions in subgroups unreasonable. All results are adjusted for age, sex, education and income. Results were similar in models accounting for use of antihypertensive and cholesterol-lowering medicines and genetic syndromes associated with aortic disease.

Conclusion

Participation in a long-distance skiing event was associated with lower risk of aortic disease and aortic dissection. Faster completion of the race was strongly associated with lower incidence of aortic disease. If causal, this study suggests that high physical activity and exercise may be protective against aortic disease.

Kaplan-Meier Aorta disease

Funding Acknowledgement

Type of funding source: None

Postmastectomy Radiation Therapy Planning After Immediate Implant-based Reconstruction Using the European Society for Radiotherapy and Oncology-Advisory Committee in Radiation Oncology Practice Consensus Guidelines for Target Volume Delineation

AIMS

To evaluate how common radiation therapy techniques perform in the setting of the new European Society for Radiotherapy and Oncology-Advisory Committee in Radiation Oncology Practice (ESTRO-ACROP) delineation recommendations for immediate breast reconstruction (IBR).

MATERIALS AND METHODS

Seven Danish radiation therapy centres and six international European centres participated in this project. Two breast cancer cases (one left-sided and one right-sided) with a retropectoral implant were chosen for radiation therapy planning using deep-inspiration breath-hold. Target volumes were delineated according to ESTRO-ACROP delineation recommendations. The centres were asked to plan the cases using any radiation therapy technique according to the Danish Breast Cancer Group plan objectives.

RESULTS

In total, 35 treatment plans were collected. Half of the submitted plans, for both the left-sided and the right-sided case, used the field-in-field (FiF) technique (nine for each), a quarter used volumetric arc radiation therapy (VMAT; five for right-sided, four for left-sided) and the remaining quarter was a mix of inverse intensity-modulated radiation therapy (IMRT), helicoidal therapy and hybrid (combined open fields and VMAT) techniques. Mean clinical target volume doses were in the range 99-102% of the prescribed dose. The median FiF mean heart dose (MHD) for right-sided radiation therapy was 1 Gy (range 0.8-3.7) and 5.2 Gy for left-sided radiation therapy (range 2.2-6.5). For right-sided radiation therapy, the median VMAT MHD was 3.42 Gy, for IMRT was 2.3 Gy and for helicoidal therapy was 5.1 Gy. For left-sided radiation therapy, the median VMAT MHD was 6.3 Gy, for IMRT was 7.8 Gy and for helicoidal therapy was 7.3 Gy.

CONCLUSIONS

Different radiation therapy techniques could be used to plan radiation therapy in the setting of IBR. FiF provided good coverage with acceptable organ at risk doses. The best dose distribution results as a trade-off between the objectives of target volume coverage and high-dose organ at risk inclusion. The radiation therapy technique affects the interplay between these objectives.

THU0145 INDICATIONS AND INCIDENCE OF TREATMENT WITH ANTIDEPRESSANTS IN PATIENTS WITH RHEUMATOID ARTHRITIS AND MATCHED CONTROLS

Background:

The incidence of depression is about 1.5-2 times higher in patients with rheumatoid arthritis (RA) versus controls. (1, 2) Previous data on treatment with antidepressants has pointed to an almost equal distribution of indications between depression and other indications. (3)

Objectives:

To describe and compare indications and the incidence of treatment with antidepressants in patients with RA and matched controls.

Methods:

The study involved an inception cohort of patients with incident RA ascertained from 1995 to 2002 according to the American College of Rheumatology 1987 classification criteria (4) and randomly drawn, population controls with the same age, sex, and area of residence (ratio 1:5). Indications on redeemed prescriptions were included in the Danish National Prescription Register from 2004 and we collected data on all prescriptions for antidepressants (Anatomical Therapeutic Classification code N06A) and counted person-years (PY) at risk from 01.01.2004 to 31.12.2017, death, or migration. The incidence of first treatment was evaluated as defined daily dose (DDD) for two definitions of exposure (DDD>0, DDD>178) within one calendar year together with the positive indication depression after one year of run-in.

Results:

The current analyses involved 431 RA patients and 2167 controls (median age at inclusion: 59 years, 70% females; RA patients: 20% erosive, 74% rheumatoid factor positive). The most frequent indication for treatment with antidepressants was depression (Table 1).

Table 1.

Indication on prescriptions for antidepressants, % (95% confidence interval (CI))

Rheumatoid arthritis (n=6,955)Controls(n=33,740)Depressive disorders62.3 (61.2-63.5)62.7 (62.2-63.2)Anxiety disorders5.4 (4.9-6.0)3.9 (3.7-4.1)Nervous system medications6.5 (5.9-7.1)6.8 (6.6-7.1)Other indications0.2 (0.0-0.3)0.2 (0.2-0.2)No or missing indications25.6 (24.6-26.7)26.3 (25.9-26.8)

There were no significant differences in the incidence of treatment with the indication depression in patients versus controls(Table 2).

Table 2.

Incidence rate ratio for treatment with antidepressants

DDD>0DDD>178Rheumatoid arthritis (Events/PY)Controls (Events/PY)Incidence rate ratio (95% CI)Rheumatoid arthritis (Events/PY)Controls (Events/PY)Incidence rate ratio (95% CI)Overall98/3,720471/19,2291.08(0.86-1.34)73/3,893339/20,3381.13 (0.87-1.46)SexFemales79/2,616354/13,4601.15 (0.89-1.47)61/2,753264/14,2991.20 (0.89-1.59)Males19/1,104117/5,7690.85 (0.49-1.39)12/1,14175/6,0390.85 (0.42-1.57)Age15-345/17524/9621.15 (0.34-3.07)4/18821/1,0221.04 (0.26-3.07)35-443/52231/2,3490.44 (0.85-1.40)3/52420/2,5010.72 (0.14-2.42)45-5414/73164/3,8711.16 (0.60-2.09)10/77340/4,1221.33 (0.59-2.71)55-6425/1,198128/6,2001.01 (0.63-1.56)17/1,25384/6,4981.05 (0.58-1.78)65-7437/849158/4,5981.27 (0.86-1.82)28/892120/4,8741.28 (0.81-1.94)75+14/24666/1,2481.08 (0.56-1.94)11/26554/1,3211.02 (0.48-1.97)

Conclusion:

The main indication for prescribing antidepressants in patients with RA was depression. Patients with RA were not exposed to antidepressants more often than controls. This could be due to prescription bias or reflect pertinent choice of treatment in patients with RA.

References:

[1]Wang SL, et al. PLoS One 2014;9:e107791.

[2]Marrie RA, et al. Arthritis Care Res 2018;70:970-8.

[3]Wong J, et al. JAMA 2016;315:2230-2.

[4]Pedersen JK, et al. Scand J Rheumatol 2018;47:371-7.

Acknowledgments:

The study was supported by the Danish Rheumatism Association

Disclosure of Interests:

None declared

The Widowhood Effect–mortality and Adverse Health Effects When Losing a Spouse in Old Age

Introduction

Losing one's spouse is a major life event which is associated to an increased risk of mental health problems as depression and sleep-disorders. There is also an increased risk of adverse effects on physical health, and even an increased risk of mortality. A phenomena called “the widowhood effect” Though this is well-known clinically, few studies have established the extent of the problem in old age.

Objectives

This study aims to examine the risk of mortality associated to widowhood in old age, and adverse health effects both regarding physical and mental health.

Methods

A nationwide register-based case control study. All Danish people aged 65 years and above who became widowed in the period of 2000–2010 are included. A background population sample of 4:1 is matched on age and gender. By using the personal identification number a linkage between registers containing information regarding health service use, pharmacologic use and demographic information is made. Mortality is analysed using Kaplan-Meier estimate and the statistical comparison between the groups is done by Cox-regression. Adverse health effects are assessed by the health care use and pharmacological use, and are compared between the two groups by t-test, linear and logistic regression depending on the variables.

Results

The study is under conduction, results will be presented.

Conclusions

Widowhood in old age has been associated to an increased risk of mortality and adverse health effects. This study assesses the outcome of this in a nationwide register-based sample.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

P1886Validation of the MB-LATER score prediction ability for recurrent atrial fibrillation after electrical cardioversion

Introduction

The MB-LATER score (Male, Bundle brunch block, Left atrium ≥47 mm, Type of AF [paroxysmal, persistent or long-standing persistent], and ER-AF=early recurrent AF during first three months) was originally developed for prediction of late AF recurrences post AF catheter ablation (CA-AF). Subsequently, the score has been internationally validated in multiple AF cohorts, showing a good prediction ability for recurrent AF post AF-CA. We assessed prediction ability of the MB-LATER score for recurrent AF after successful electrical cardioversion (ECV) of AF.

Methods

The retrospective study included a Serbian and Icelandic centre, enrolling patients post successful ECV of AF in the period between January 2014 and February 2016. Of 580 patients, 136 (23.4%) were excluded because incomplete data needed for the MB-LATER score calculation. AF episodes lasting ≤7 days before ECV were classified as paroxysmal AF, and the ER-AF component of the MB-LATER score was excluded from the analysis because of different clinical implications in the setting of ECV. The study outcome was defined as the time to first recurrence of AF post successful ECV. Patients post successful ECV were seen at 1 and 6 months post ECV and every 12 months thereafter.

Results

Among 444 patients (median age 68 years [IQR 60.0–74.6], 289 males [65.2%], 200 [45.0%] with non-paroxysmal AF. AF re-occurred in 283 patients (63.7%) after a median of 233.5 [IQR 44–366]) days post successful ECV. Patients with recurrent AF had significantly higher median MB-LATER score than those without (1 [IQR 1–2] vs. 2 [IQR 1–2], p<0.001). On univariate analysis, the MB-LATER score was significantly associated with time to AF recurrence post ECV (Hazard Ratio 1.20; 95% CI 1.07–1.35, p=0.003), showing modest but statistically significant prediction ability for recurrent AF post successful ECV (c-statistic 0.61; 95% CI 0.56–0.66, p<0.001). The Kaplan-Meyer survival free from AF post successful ECV was significantly better for patients with a MB-LATER score of <2 than for those with a score of ≥2 (log-rank p=0.005) (Fig 1.).

Figure 1

Conclusion

In our analysis of an international cohort of AF patients post successful ECV, the MB-LATER score showed a modest but statistically significant prediction ability for recurrent AF post ECV. Reliable prediction of recurrent AF post ECV could inform patient selection and treatment decision-making. Further prospective validation of the MB-LATER score prediction ability for recurrent AF post ECV is underway.

Using a Robust and Sensitive GFP-Based cGMP Sensor for Real-Time Imaging in Intact Caenorhabditis elegans

cGMP plays a role in sensory signaling and plasticity by regulating ion channels, phosphodiesterases, and kinases. Studies that primarily used genetic and biochemical tools suggest that cGMP is spatiotemporally regulated in multiple sensory modalities. FRET- and GFP-based cGMP sensors were developed to visualize cGMP in primary cell culture and Caenorhabditis elegans to corroborate these findings. While a FRET-based sensor has been used in an intact animal to visualize cGMP, the requirement of a multiple emission system limits its ability to be used on its own as well as with other fluorophores. Here, we demonstrate that a C. elegans codon-optimized version of the cpEGFP-based cGMP sensor FlincG3 can be used to visualize rapidly changing cGMP levels in living, behaving C. elegans We coexpressed FlincG3 with the blue-light-activated guanylyl cyclases BeCyclOp and bPGC in body wall muscles, and found that the rate of change in FlincG3 fluorescence correlated with the rate of cGMP production by each cyclase. Furthermore, we show that FlincG3 responds to cultivation temperature, NaCl concentration changes, and sodium dodecyl sulfate in the sensory neurons AFD, ASEL/R, and PHB, respectively. Intriguingly, FlincG3 fluorescence in ASEL and ASER decreased in response to a NaCl concentration upstep and downstep, respectively, which is opposite in sign to the coexpressed calcium sensor jRGECO1a and previously published calcium recordings. These results illustrate that FlincG3 can be used to report rapidly changing cGMP levels in an intact animal, and that the reporter can potentially reveal unexpected spatiotemporal landscapes of cGMP in response to stimuli.

Monitoring and Modeling the Rapid Evolution of Earth's Newest Volcanic Island: Hunga Tonga Hunga Ha'apai (Tonga) Using High Spatial Resolution Satellite Observations

We have monitored a newly erupted volcanic island in the Kingdom of Tonga, unofficially known as Hunga Tonga Hunga Ha'apai, by means of relatively frequent high spatial resolution (~50 cm) satellite observations. The new ~1.8 km2 island formed as a tuff cone over the course of a month-long hydromagmatic eruption in early 2015 in the Tonga-Kermadec volcanic arc. Such ash-dominated eruptions usually produce fragile subaerial landscapes that wash away rapidly due to marine erosion, as occurred nearby in 2009. Our measured rates of erosion are ~0.00256 km3/year from derived digital topographic models. Preliminary measurements of the topographic expression of the primary tuff cone over ~30 months suggest a lifetime of ~19 years (and potentially up to 42 years). The ability to measure details of a young island's landscape evolution using satellite remote sensing has not previously been possible at these spatial and temporal resolutions.

Body size and risk of atrial fibrillation: a cohort study of 1.1 million young men

BACKGROUND

Whilst tall stature has been related to lower risk of vascular disease, it has been proposed as a risk factor for atrial fibrillation. Little is known about other anthropometric measures and their joint effects on risk of atrial fibrillation.

OBJECTIVES

We aim to investigate associations and potential joint effects of height, weight, body surface area (BSA) and body mass index (BMI) with risk of atrial fibrillation.

METHODS

In a cohort covering 1 153 151 18-year-old men participating in the Swedish military conscription (1972-1995), Cox regression was used to investigate associations of height, weight, BSA and BMI with risk of atrial fibrillation.

RESULTS

During a median of 26.3 years of follow-up, higher height was associated with higher risk of atrial fibrillation (hazard ratio [HR] 2.80; 95% CI 2.63-2.98; for 5th vs. 1st quintile) and so was larger BSA (HR 3.05; 95% CI 2.82-3.28; for 5th vs. 1st quintile). Higher weight and BMI were to a lesser extent associated with risk of atrial fibrillation (BMI: 1.42; 95% CI 1.33-1.52, for 5th vs. 1st quintile). We found a multiplicative joint effect of height and weight. Adjusting for muscle strength, exercise capacity and diseases related to atrial fibrillation attenuated these measures.

CONCLUSIONS

Higher height and weight are strongly associated with higher risk of atrial fibrillation. These associations are multiplicative and independent of each other and are summarized in a strong association of body surface area with risk of atrial fibrillation. The mechanisms remain unknown but may involve increased atrial volume load with larger body size.

Bennett’s Fracture

The relationship between the quality of redaction and the occurrence of arthritic changes, symptoms and disability was studied in 41 Bennett’s fractures. Excellent position was obtained in five of nine fractures treated by closed reduction and plaster immobilisation, in four of six fractures treated by percutaneous K wire fixation and in 18 of 26 fractures treated by open reduction. After a median interval of 7.3 years, 15 of 18 reviewed patients with fractures healed in excellent position were free of symptoms, but this was so in only six of 13 fractures with residual displacement. The remainder had intermittent slight pain. Radiographic signs of arthritis was found in ten of 24 patients: three of 14 patients with excellent reduction and seven of ten patients with residual displacement.

Biosensor cell assay for measuring real-time aldosterone-induced release of histamine from mesenteric arteries

AIMS

The aims were to develop a method for real-time detection of histamine release and to test whether incubation with aldosterone induces histamine release from isolated, perfused mice mesenteric arteries.

METHODS

Fura-2-loaded HEK-293 cells transfected with the histamine H1 receptor was used as a sensitive biosensor assay for histamine release from isolated mouse mesenteric arteries. Activation of the H1 receptor by histamine was measured as an increased number of intracellular Ca²⁺ transient peaks using fluorescence imaging.

RESULTS

The developed biosensor was sensitive to histamine in physiological relevant concentrations and responded to substances released by the artery preparation. Aldosterone treatment of mesenteric arteries from wild-type mice for 50 min resulted in an increased number of intracellular Ca²⁺ transient peaks in the biosensor cells, which was significantly inhibited by the histamine H1 blocker pyrilamine. Mesenteric arteries from mast cell-deficient SASH mice induced similar pyrilamine-sensitive Ca²⁺ transient response in the biosensor cells. Mesenteric arteries from wild-type and SASH mice expressed histamine decarboxylase mRNA, indicating that mast cells are not the only source of histamine release.

CONCLUSION

The developed biosensor assay can measure release of substances from vascular preparations. Histamine is released from the vessel preparation in response to aldosterone treatment independently of mast cells. The assay enables us to study a new signaling mechanism for vascular responses induced by aldosterone.

Diagnostic Conversion to Bipolar Disorder in Unipolar Depressed Patients Participating in Trials on Antidepressants

Objective

In unipolar depressed patients participating in trials on antidepressants, we investigated if illness characteristics at baseline could predict conversion to bipolar disorder.

Method

A long-term register-based follow-up study of 290 unipolar depressed patients with a mean age of 50.8 years (SD = 11.9) participating in three randomized trials on antidepressants conducted in the period 1985–1994. The independent effects of explanatory variables were examined by applying Cox regression analyses.

Results

The overall risk of conversion was 20.7%, with a mean follow-up time of 15.2 years per patient. The risk of conversion was associated with an increasing number of previous depressive episodes at baseline, [HR 1.18, 95% CI (1.10–1.26)]. No association with gender, age, age at first depressive episode, duration of baseline episode, subtype of depression or any of the investigated HAM-D subscales included was found.

Limitations

The patients were followed-up through the Danish Psychiatric Central Research Register, which resulted in inherent limitations such as possible misclassification of outcome.

Conclusion

In a sample of middle-aged hospitalized unipolar depressed patients participating in trials on antidepressants, the risk of conversion was associated with the number of previous depressive episodes. Therefore, this study emphasizes that unipolar depressed patients experiencing a relatively high number of recurrences should be followed more closely, or at least be informed about the possible increased risk of conversion.

Antipsychotic treatment effects on cardiovascular, cancer, infection, and intentional self-harm as cause of death in patients with Alzheimer's dementia

Background

Alzheimer's disease (AD), the most common disease causing dementia, is linked to increased mortality. However, the effect of antipsychotic use on specific causes of mortality has not yet been investigated thoroughly.

Methods

Utilizing the Danish nationwide registers, we defined a cohort of patients diagnosed with AD. Utilizing separate Cox regressions for specific causes of mortality, we investigated the effects of cumulative antipsychotic dosage after diagnosis and current antipsychotic exposure in the time period 2000–2011.

Results

In total, 45,894 patients were followed for 3,803,996 person-years. A total of 6129 cardiovascular related deaths, 2088 cancer related deaths, 1620 infection related deaths, and 28 intentional self-harm related deaths are presented. Current antipsychotic exposure increased mortality rate with HR between 1.92 and 2.31 for cardiovascular, cancer, and infection related death. Cumulative antipsychotic dosages were most commonly associated with increased rates of mortality for cardiovascular and infection as cause of death, whereas the associations were less clear with cancer and intentional self-harm as cause of death.

Conclusions

We showed that cumulative antipsychotic drug dosages increased mortality rates for cardiovascular and infection as cause of death. These findings highlight the need for further investigations of long-term effects of treatment and of possible sub-groups who could benefit from treatment.

Cancellous Bone Strength Measurements with the Osteopenetrometer

An instrument designed to measure cancellous bone strength at the tibial and femoral condyles during total knee replacement is described and evaluated with respect to the relationship of measurements to conventional compression tests on machined specimens in a material testing machine.

The instrument, referred to as an osteopenetrometer, indirectly measures the force and depth of penetration of a needle that is advanced into the cancellous bone at constant speed. A small computer controls the measuring procedure and corrects the force readings for resistance in the hydraulic system.

The relationship between osteopenetrometer measurements and compression tests is best described by a power law, with correlation coefficients of approximately 0.90 when ultimate stress data were compared. A 2.5 mm pointed needle with the shaft milled to 2.3 mm to avoid friction along the needle shaft is favoured for clinical measurements since readings from different depths beneath the resection surface may then be directly compared.

The error of measurement was assessed by comparison of observed and smoothed data from measurements across tibial and femoral condylar resection surfaces. Ninety-nine per cent tolerance limits of ± 3.0 MPa (compared to a range of 0–40 MPa in units peculiar to the osteopenetrometer) were found.

Cumulative dosages of antipsychotic drugs are associated with increased mortality rate in patients with Alzheimer's dementia

OBJECTIVE

We wished to investigate the effects of cumulative dosages of antipsychotic drug in Alzheimer's dementia, when controlling for known risk factors, including current antipsychotic exposure, on all-cause mortality.

METHOD

We utilized a nationwide, population-based, retrospective cohort study design with mortality as outcome in individual patients diagnosed with Alzheimer's dementia.

RESULTS

We included a total of 45 894 patients and followed them for 3 803 996 person-years in total, presenting 27 894 deaths in the study population. Cumulative antipsychotic exposure increased mortality: more than 0 Daily Defined Dosage (DDDs) but less than 90: HR 2.20, 95% CI (2.14-2.27), P < 0.001; more than or equal to 90 DDDs but less than 365: HR 1.81, 95% CI (1.74-1.89), P < 0.001; more than or equal to 365 DDDs but less than 730: HR 1.38, 95% CI (1.428-1.49), P < 0.001; and more than or equal to 730 DDDs: HR 1.06, 95% CI (0.95-1.18), P = 0.322, when controlling for proxy markers of severity, somatic and mental comorbid disorders.

CONCLUSION

In this nationwide cohort study of 45 894 patients diagnosed with Alzheimer's dementia, we found that cumulative dosages of antipsychotic drugs were associated with increased mortality rates.

Relative blood loss and operative time can predict length of stay following orthognathic surgery

The aim of this study was to investigate the length of stay (LOS) following orthognathic surgery and thereby to establish a benchmark. The secondary aim was to identify predictors of postoperative LOS following orthognathic surgery. Patients were treated consecutively during the period 2010 to 2012. Inclusion criteria were (1) patient age ≥18 years, and (2) surgery involving a three-piece Le Fort I osteotomy, or a bilateral sagittal split osteotomy (BSSO), or bimaxillary surgery. A total of 335 patients were included. The following data were recorded: height, weight, body mass index (BMI), age, sex, operative time, intraoperative blood loss, and type of surgery. LOS was defined as the duration of time from date of surgery to date of discharge. The average LOS was 1.3 days following Le Fort I osteotomy, 1.3 days following BSSO, and 1.8 days following bimaxillary surgery. In the multivariate regression model (R(2)=0.11), predictors of a prolonged LOS were operative time (P<0.001) and relative blood loss (P=0.002). No significant effect of age, BMI, sex, or treatment on LOS was observed. The short duration of LOS found in this study supports the possibility of increasing outpatient pathways for selected patients.

Factors influencing intraoperative blood loss in orthognathic surgery

This retrospective study aimed to identify factors of importance for intraoperative blood loss relative to total blood volume in patients undergoing orthognathic surgery. The study included 356 patients treated consecutively at a Danish university hospital between 1 January 2010 and 31 December 2012. Inclusion criteria were (1) patient age ≥18 years and (2) patient undergoing a three-piece Le Fort I osteotomy, a bilateral sagittal split osteotomy, or a combination of the two. The patient-specific relative blood loss was calculated as a percentage by dividing the intraoperative blood loss by the estimated preoperative total blood volume, and then correlated with body mass index (BMI), age, sex, operating time, and treatment modality in a multivariate stepwise regression analysis. Operating time (P<0.001), BMI (P<0.001), and treatment modality (P<0.001) had a significant impact on relative blood loss; no significant effect of age or sex was observed. The coefficient of determination of relative blood loss was R(2)=0.34. In conclusion, this study introduces relative blood loss as a patient-specific measure of intraoperative blood loss. Average relative blood loss in this patient sample was 6.5%. Extensive surgery, a prolonged operating time, and reduced BMI significantly increase the intraoperative relative blood loss in patients undergoing orthognathic surgery.

Elderly-study – treatment for alcohol problems among 60+

Introduction

The western societies have a rapidly aging population and an increasing number of elderly with alcohol use disorders.

Objective

The purpose of the elderly study is to develop and test an outpatient behavior therapy program for people with an alcohol use disorders.

Aim of this abstract

To investigate the association between ages, gender, drinking pattern and psychology distress.

Method

The study is a randomized study expected to enroll and treat 1000 participants aged 60+ years before April 2017; 200 in USA; 400 in Germany and 400 in Denmark. To be included in the study the participants have to fulfil the DSM-5 criteria for alcohol use disorder. All participants are examined at baseline, and at four follow up interviews. After the baseline interview all participants are randomized to Motivational Enhancement Therapy (MET); or MET followed by 8 weeks of counseling based on the Community Reinforcement Approach (CRA) with a module added to address problems relevants to elderly people.

Results

The presentation will include baseline characteristics of the Danish participants including demographics, expectations to treatment, history of drinking in the last 90 days before baseline and their psychological distress. We have now enrolled 259 participants in the Danish database. We expect to present results from 320 patients.

Conclusion

The data will present information about the profile of 60+ years’ individuals seeking treatment for alcohol use disorder, and thereby provide knowledge about which characteristics that may be important when planning treatment for this age group.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Exercise addicts with injuries are in risk of depression

Introduction

Exercise addiction is characterized by increasing exercise amounts, withdrawal symptoms and lack of control. Exercisers with addiction continue to exercise in spite of pain and injury because they use exercise to regulate emotions, identity and self-esteem. How do they react to injuries?

Objectives

It is hypothesized that exercise addiction is a risk factor for emotional distress when an injury occur due to withdrawal symptoms and lack of identity.

Aims

To estimate the prevalence of exercise addiction in exercisers with injuries at the musculoskeletal system and to test the relationship between addiction and emotional distress (depression and stress).

Methods

The Exercise Addiction Inventory was used to identify exercise addiction. To measure depression and stress we used the Major Depression Inventory (MDI) and the Perceived Stress Scale (PSS). Participants (n = 694) were regular exercisers with injuries at foot, knee or shoulder at an orthopedic hospital department.

Results

The prevalence of exercise addiction was 7.6%. We found that exercisers with addiction reported more emotional distress in terms of higher MDI-scores 18.0 (SD = 11.0) versus 11.7 (SD = 9.1); P = 0.00 and in total PSS-score 17.6 (SD = 7.2) versus 13.9 (SD = 6.8); P = 0.00. Chi2 analyses showed that 25% of the addicted exercisers met the criteria for clinical depression, while only 11% of the non-addicted exercisers were depressed; P = 0.00.

Conclusions

Exercisers with addiction appear at somatic departments treating musculoskeletal injuries. It is a vulnerable group characterized by elevated levels of depressive symptoms and clinical stress. We recommend to offer psychological interventions focusing on emotional distress and prevention of re-injury by reducing excessive and obsessive exercise patterns.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Effect of unilateral mandibular distraction osteogenesis on mandibular morphology in rabbits with antigen-induced temporomandibular joint arthritis

Aim was to evaluate effect of unilateral distraction osteogenesis (DO) on mandibular morphology in rabbits with antigen-induced arthritis in the temporomandibular joint (TMJ). Forty 8-week-old rabbits were divided into four groups. In groups A,C, arthritis was induced in the right TMJ. Groups A,B underwent DO. Group D served as control group. Cephalometric analysis of mandibular angle, mandibular ramus height, mandibular collum height, and total posterior mandibular height was done on CT-scans preoperatively (T0), after distraction (T1), and at euthanasia (T2). Two-factor ANOVA evaluated the effect of DO and antigen-induced arthritis. No effect of DO or arthritis was observed on mandibular angle or mandibular collum height. For T0-T1, DO increased mandibular ramus height 12.3% (95% CI 5.2-19.4%) in group B (P=0.001) and total posterior mandibular height 6.2% (95% CI 0.3-12.1%) in group A (P=0.04) and 10.0% (95% CI 4.3-15.7%) in group B (P=0.001). For T1-T2, no significant changes occurred in arthritic rabbits (group A). In conclusion, DO increased total posterior mandibular height in rabbits with arthritis. Postoperatively, no significant effect of DO was observed in rabbits with arthritis. Mandibular DO could be a viable treatment modality in patients with TMJ-arthritis.

Lessons learned from the intrinsic subtypes of breast cancer in the quest for precision therapy

BACKGROUND

Wide variability in breast cancer, between patients and within each individual neoplasm, adds confounding complexity to the treatment of the disease. In clinical practice, hormone receptor status has been used to classify breast tumours and to guide treatment. Modern classification systems should take the wide tumour heterogeneity into account to improve patient outcome.

METHODS

This article reviews the identification of the intrinsic molecular subtypes of breast cancer, their prognostic and therapeutic implications, and the impact of tumour heterogeneity on cancer progression and treatment. The possibility of functionally addressing tumour-specific characteristics in in vivo models to inform decisions for precision therapies is also discussed.

RESULTS

Despite the robust breast tumour classification system provided by gene expression profiling, heterogeneity is also evident within these molecular portraits. A complicating factor in breast cancer classification is the process of selective clonality within developing neoplasms. Phenotypically and functionally distinct clones representing the intratumour heterogeneity might confuse molecular classification. Molecular portraits of the heterogeneous primary tumour might not necessarily reflect the subclone of cancer cells that causes the disease to relapse. Studies of reciprocal relationships between cancer cell subpopulations within developing tumours are therefore needed, and are possible only in genetically engineered mouse models or patient-derived xenograft models, in which the treatment-induced selection pressure on individual cell clones can be mimicked.

CONCLUSION

In the future, more refined classifications, based on integration of information at several molecular levels, are required to improve treatment guidelines. Large-scale translational research efforts paved the way for identification of the intrinsic subtypes, and are still fundamental for ensuring future progress in cancer care.