Clinical bleeding diathesis, laboratory haemostatic aberrations and survival in dogs infected with Angiostrongylus vasorum: 180 cases (2005-2019).

OBJECTIVES: Bleeding diathesis is a complication in dogs infected with Angiostrongylus vasorum. This retrospective study investigated clinical and laboratory haemostatic differences in A. vasorum-positive dogs with and without signs of bleeding and impact of bleeding on survival. MATERIALS AND METHODS: Demographics, type of clinical bleeding, haematocrit and a range of haemostatic tests, including thromboelastography and derived velocity curves were retrospectively registered from A. vasorum-positive dogs. All parameters were compared between dogs with and without signs of bleeding using univariable analyses. Binomial and multinomial regression models were applied to examine specific indicators in the bleeding dogs. P-values were false discovery rate adjusted, and adjusted P<0.05 was considered significant. RESULTS: One hundred and eighty dogs entered the study, including 65 dogs (36.1%) presenting with bleeding diathesis. Different types of cutaneous and mucosal bleeding were the most common clinical findings. Twenty dogs presented with neurological signs associated with intracranial and intra-spinal bleeding. One hundred and thirty-seven dogs had haematological and/or haemostatic laboratory analyses performed. Haematocrit, platelet count, thromboelastographic angle, maximum amplitude, global clot strength, maximum rate of thrombin generation and total thrombin generation were decreased, while prothrombin time was prolonged in bleeding dogs. Survival rate of bleeding dogs was lower at hospital discharge (76.9%) and 1 month after diagnosis (66.0%) than in dogs without signs of bleeding (94.8% and 90.1% at discharge and at 1 month, respectively). CLINICAL SIGNIFICANCE: Several haemostatic aberrations were detected in A. vasorum-positive dogs with bleeding diathesis. Bleeding was identified as an important negative prognostic indicator in A. vasorum-positive dogs.

Danish military fatalities in international operations 2002-2018.

INTRODUCTION: This study describes deaths among Danish soldiers in international operations 2002-2018. Having been part of UN and later NATO forces in ex-Yugoslavia, in 2002 the first Danish contingent took part in the International Security Assistance Force mission in Afghanistan as well as Iraq. The changing role of the Danish military in international operations meant casualties, in numbers that had not yet been experienced, and necessitated a review of our procedures for handling fatalities in the military. METHODS: The study is a retrospective review of autopsy reports, Military Police reports and medical reports, and the purpose is to examine all Danish fatalities in international operations in 2002-2018 to identify potential areas of improving treatment and protection and to review the contribution of the autopsies. The mechanism of injury, the fatal injuries and causes of death and the time of death within the chain of evacuation were identified. Casualties dying at any time from site of injury until definitive care were included. RESULTS: A total of 53 soldiers died from injuries during international operations in the years 2002-2018. The majority of these (43) died from combat injuries and 10 from accidents. Four of the victims with combat injuries were not autopsied. The majority (36) of the combat deaths were caused by blast/explosions (improvised explosive devices, rocket propelled grenades, fragments), while 7 were caused by bullets. 39 combat victims died instantly on the site or at the arrival to the field hospital, 4 were treated in field hospital and 2 of these were transported back to Denmark. CONCLUSIONS: Most combat fatalities result from fragmentation and blast injury. Forensic autopsies provide valuable information regarding injuries, weaponry, the efficiency of protective equipment and the quality of medical intervention in military fatalities and are recommended in all military fatalities in order to prevent avoidable casualties in the future.

Biopsy-derived oral keratinocytes - A model to potentially test for oral mucosa radiation sensitivity.

Purpose: To establish stable in vitro growth of keratinocytes from very small biopsy specimens and successfully apply new test systems to determine their radiosensitivity. Materials and Methods: Oral mucosa biopsies (diameter: 1.7 mm) from 15 subjects were immobilized with custom-made cups onto culture plates. Outgrowing cells were tested for cytokeratin 5/14 and Ki67, expanded, radiated at different doses, and seeded onto circumscribed areas before being allowed to spread centrifugally. In this newly developed spreading assay, cell-covered areas were measured by image analysis. For statistical analysis, a linear mixed regression model was used; additionally, results were correlated to the radiation dose applied. Colony forming efficiency (CFE) was used to validate the results. DNA damage repair was analysed by gammaH2AX and 53BP1 foci quantification using immunofluorescence microscopy 24 h and 96 h after irradiation. Results: Stable keratinocyte growth continued for up to 7 weeks in 14 biopsies. Cells spread reliably from an initial 16.6 mm2 up to a median of 119.2 mm2 (range: 54.4-290). Radiated cells spread to only 100.7 mm2 (2 Gy; range: 55.3-266.7); 73.2 mm2 (4 Gy; 15-240.4); 47 mm2 (6 Gy; 2-111.9), and 22.7 mm2 (8 Gy; 0-80). Similarly, CFE decreased from 0.223 (0 Gy) to 0.0028 (8 Gy). Using an individual donor as a random factor, cell spread correlated with CFE, where radiation dose was the main driver (decrease by 0.50, adjusted for area). Upon irradiation with 6 Gy, radiation-induced DNA damage was increased after 24 h in all samples, and even after 96 h in 5 out of 7 samples, as detected by a higher number of gammaH2AX/53BP1 foci in irradiated cells (mean 3.7 for 24 h; mean 0.6 for 96 h). Conclusion: In vitro propagation of keratinocytes derived from a small biopsy is feasible. Radiation impairs cellular migration and proliferation, and the newly described spreading assay allows ranking for cellular radioresistance. The keratinocyte model also supports classical functional assays such as clonogenic survival and DNA double strand repair. The clinical relevance awaits upcoming investigations.

Electrical Impedance Plethysmography Versus Tonometry To Measure the Pulse Wave Velocity in Peripheral Arteries in Young Healthy Volunteers: a Pilot Study.

The leading cause of health loss and deaths worldwide are cardiovascular diseases. A predictor of cardiovascular diseases and events is the arterial stiffness. The pulse wave velocity (PWV) can be used to estimate arterial stiffness non-invasively. The tonometer is considered as the gold standard for measuring PWV. This approach requires manual probe fixation above the artery and depends on the skills of the operator. Electrical impedance plethysmography (IPG) is an interesting alternative using skin surface sensing electrodes, that is miniaturizable, cost-effective and allows measurement of deeper arteries. The aim of this pilot study was to explore if IPG can be a suitable technique to measure pulse wave velocity in legs as an alternative for the tonometer technique. The PWV was estimated by differences in the ECG-gated pulse arrival times (PAT) at the a. femoralis, a. popliteal, a. tibialis dorsalis and a. dorsalis pedis in nine healthy young adults using IPG and the SphygmoCor tonometer as a reference. The estimated PWV results from bioimpedance and the tonometer were fairly in agreement, and the beat-to-beat variability in PAT was similar. This pilot study indicates that the use of IPG may be a good alternative for estimating PWV in the legs.

Weyl Consistency Conditions and γ_{5}.

The treatment of γ_{5} in dimensional regularization leads to ambiguities in field-theoretic calculations, of which one example is the coefficient of a particular term in the four-loop gauge beta functions of the standard model. Using Weyl consistency conditions, we present a scheme-independent relation between the coefficient of this term and a corresponding term in the three-loop Yukawa beta functions, where a semi-naïve treatment of γ_{5} is sufficient, thereby fixing this ambiguity. We briefly outline an argument by which the same method fixes similar ambiguities at higher orders.

Proteome Profiling of Primary Pancreatic Ductal Adenocarcinomas Undergoing Additive Chemoradiation Link ALDH1A1 to Early Local Recurrence and Chemoradiation Resistance.

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis with frequent post-surgical local recurrence. The combination of adjuvant chemotherapy with radiotherapy is under consideration to achieve a prolonged progression-free survival (PFS). To date, few studies have determined the proteome profiles associated with response to adjuvant chemoradiation. We herein analyzed the proteomes of primary PDAC tumors subjected to additive chemoradiation after surgical resection and achieving short PFS (median 6 months) versus prolonged PFS (median 28 months). Proteomic analysis revealed the overexpression of Aldehyde Dehydrogenase 1 Family Member A1 (ALDH1A1) and Monoamine Oxidase A (MAOA) in the short PFS cohort, which were corroborated by immunohistochemistry. In vitro, specific inhibition of ALDH1A1 by A37 in combination with gemcitabine, radiation, and chemoradiation lowered cell viability and augmented cell death in MiaPaCa-2 and Panc 05.04 cells. ALDH1A1 silencing in both cell lines dampened cell proliferation, cell metabolism, and colony formation. In MiaPaCa-2 cells, ALDH1A1 silencing sensitized cells towards treatment with gemcitabine, radiation or chemoradiation. In Panc 05.04, increased cell death was observed upon gemcitabine treatment only. These findings are in line with previous studies that have suggested a role of ALDH1A1 chemoradiation resistance, e.g., in esophageal cancer. In summary, we present one of the first proteome studies to investigate the responsiveness of PDAC to chemoradiation and provide further evidence for a role of ALDH1A1 in therapy resistance.

Liraglutide and cardiovascular outcomes in adults with overweight or obesity: A post hoc analysis from SCALE randomized controlled trials.

The cardiovascular safety of liraglutide, a glucagon-like peptide-1 receptor agonist approved for weight management at a dose of 3.0 mg, was evaluated post hoc using data from 5908 participants in 5 randomized, double-blind, placebo-controlled clinical trials. Participants were randomized to liraglutide or a comparator group (placebo or orlistat). The objective was to evaluate whether cardiovascular risk was increased with liraglutide treatment. The primary composite outcome of this time-to-event analysis was the first occurrence of cardiovascular death, nonfatal myocardial infarction or nonfatal stroke. These cardiovascular events were adjudicated prospectively for three of the trials and retrospectively for two trials by an event adjudication committee. The primary outcome was analyzed using a Cox proportional hazards model, stratified by trial. With liraglutide 3.0 mg, 8 participants had positively adjudicated cardiovascular events (1.54 events/1000 person-years) compared to 10 participants in the comparators group (3.65 events/1000 person-years). The hazard ratio for liraglutide 3.0 mg compared to comparators was 0.42 (95% confidence interval, 0.17-1.08). In this analysis, liraglutide 3.0 mg treatment was not associated with excess cardiovascular risk. However, the wide confidence intervals and retrospective adjudication of events in two of the trials are limitations of the analysis.

Pancreatic stellate cells in pancreatic cancer: In focus.

Pancreatic stellate cells are stromal cells that have multiple physiological functions such as the production of extracellular matrix, stimulation of amylase secretion, phagocytosis and immunity. In pancreatic cancer, stellate cells exhibit a different myofibroblastic-like morphology with the expression of alpha-smooth muscle actin, the activated form is engaged in several mechanisms that support tumorigenesis and cancer invasion and progression. In contrast to the aforementioned observations, eliminating the stromal cells that are positive for alpha-smooth muscle actin resulted in immune-evasion of the cancer cells and resulted in worse prognosis in animal models. Understanding the cancer-stromal signaling in pancreatic adenocarcinoma will provide novel strategies for therapy. Here we provide an updated review of studies that handle the topic "pancreatic stellate cells in cancer" and recent experimental approaches that can be the base for future directions in therapy.

Implementing Pharmacogenomics in Europe: Design and Implementation Strategy of the Ubiquitous Pharmacogenomics Consortium.

Despite scientific and clinical advances in the field of pharmacogenomics (PGx), application into routine care remains limited. Opportunely, several implementation studies and programs have been initiated over recent years. This article presents an overview of these studies and identifies current research gaps. Importantly, one such gap is the undetermined collective clinical utility of implementing a panel of PGx-markers into routine care, because the evidence base is currently limited to specific, individual drug-gene pairs. The Ubiquitous Pharmacogenomics (U-PGx) Consortium, which has been funded by the European Commission's Horizon-2020 program, aims to address this unmet need. In a prospective, block-randomized, controlled clinical study (PREemptive Pharmacogenomic testing for prevention of Adverse drug REactions [PREPARE]), pre-emptive genotyping of a panel of clinically relevant PGx-markers, for which guidelines are available, will be implemented across healthcare institutions in seven European countries. The impact on patient outcomes and cost-effectiveness will be investigated. The program is unique in its multicenter, multigene, multidrug, multi-ethnic, and multihealthcare system approach.

Long-term 2007-2013 monitoring of reproductive disturbance in the dun sentinel Assiminea grayana with regard to polymeric materials pollution at the coast of Lower Saxony, North Sea, Germany.

During biological effect monitoring studies of endocrine active compounds with the snail Assiminea grayana in 2007-2013, reproductive disorders including atresia, transformation of capsule/albumen glands into prostates in females and ovotestis, transformation of prostates to capsule/albumen glands, disruption of spermatogenesis, and calcification of tubules in males, were encountered in several years. The search of sources of endocrine active substances was first directed to antifouling biocides from paint particles and extended to leaching compounds from polymeric materials. In contrast to the reference sites, most of the observed disorders occurred at a station near harbors and dockyards polluted with residues from antifouling paints and polymeric materials. Beside of investigations about the potential ingestion of polymer particles by the snails, further investigations of compounds of polymeric materials with endocrine potential should follow.

Association between RANK, RANKL and OPG polymorphisms with ACPA and erosions in rheumatoid arthritis: results from a meta-analysis involving three French cohorts.

OBJECTIVES: The RANK/RANKL/osteoprotegerin (OPG) system plays a central role in the pathogenesis of bone erosions in rheumatoid arthritis (RA). The aim of this study was to test the association between 11 single-nucleotide polymorphisms (SNPs) located on RANK, RANKL and OPG genes and anticitrullinated peptide antibody (ACPA) presence or erosions in RA. PATIENTS: This work was performed on three independent samples of French patients with RA: the Etude de Suivi des PolyArthrites Indifférenciées Récentes (ESPOIR) (n=632), Rangueil Midi-Pyrénées (RMP) (n=249) and French Rheumatoid Arthritis Genetic Consortium (FRAGC) (n=590) cohorts. Genotyping: the genotyping of 11 SNPs located on RANK, RANKL and OPG were performed by PCR. STATISTICAL ANALYSES: The association between the genotypes with ACPA or erosions was first tested in the ESPOIR cohort using a χ(2) test and, in the case of significant association, replicated in the RMP and FRACG cohorts. A meta-analysis on the three cohorts was performed using the Mantel-Haenszel method. RESULTS: One SNP on RANK (rs8086340) and three SNPs on RANKL (rs7984870, rs7325635, rs1054016) were significantly associated with ACPA presence, while one SNP on OPG (rs2073618) and one SNP on RANKL (rs7325635) were significantly associated with erosions in the ESPOIR cohort. Following meta-analysis performed on the three samples, the SNP on RANK and the GGG haplotype of the three SNPs located on RANKL were both significantly associated with ACPA presence, while only the SNP on OPG remained significantly associated with erosions. CONCLUSIONS: This study identified one SNP located on RANK, one haplotype on RANKL associated with ACPA presence, and one SNP located on OPG associated with erosions in three different samples of French patients with RA.

Efficacy and safety of switching from sitagliptin to liraglutide in subjects with type 2 diabetes (LIRA-SWITCH): a randomized, double-blind, double-dummy, active-controlled 26-week trial.

AIMS: To confirm superiority on glycaemic control by switching from sitagliptin to liraglutide 1.8 mg/d versus continued sitagliptin. MATERIALS AND METHODS: A randomized, multicentre, double-blind, double-dummy, active-controlled trial across 86 office- or hospital-based sites in North America, Europe and Asia. Subjects with type 2 diabetes who had inadequate glycaemic control (glycated haemoglobin [HbA1c] 7.5-9.5% on sitagliptin (100 mg/d) and metformin (≥1500 mg daily) for ≥90 days were randomized to either switch to liraglutide (n = 203) or continue sitagliptin (n = 204), both with metformin. The primary endpoint was change in HbA1c from baseline to week 26. Change in body weight was a confirmatory secondary endpoint. RESULTS: Greater reduction in mean HbA1c was achieved with liraglutide than with continued sitagliptin [-1.14% vs. -0.54%; estimated mean treatment difference (ETD): -0.61% (95% CI -0.82 to -0.40; p < 0.0001)], confirming superiority of switching to liraglutide. Body weight was reduced more with liraglutide [-3.31 kg vs. -1.64 kg; ETD: -1.67 kg (95% CI -2.34 to -0.99; p < 0.0001)]. Nausea was more common with liraglutide [44 subjects (21.8%)] than with continued sitagliptin [16 (7.8%)]. Three subjects (1.5%) taking sitagliptin reported a confirmed hypoglycaemic episode. CONCLUSIONS: Subjects insufficiently controlled with sitagliptin who switch to liraglutide can obtain clinically relevant reductions in glycaemia and body weight, without compromising safety. A switch from sitagliptin to liraglutide provides an option for improved management of type 2 diabetes while still allowing patients to remain on dual therapy.

Paving the way of systems biology and precision medicine in allergic diseases: the MeDALL success story: Mechanisms of the Development of ALLergy; EU FP7-CP-IP; Project No: 261357; 2010-2015.

MeDALL (Mechanisms of the Development of ALLergy; EU FP7-CP-IP; Project No: 261357; 2010-2015) has proposed an innovative approach to develop early indicators for the prediction, diagnosis, prevention and targets for therapy. MeDALL has linked epidemiological, clinical and basic research using a stepwise, large-scale and integrative approach: MeDALL data of precisely phenotyped children followed in 14 birth cohorts spread across Europe were combined with systems biology (omics, IgE measurement using microarrays) and environmental data. Multimorbidity in the same child is more common than expected by chance alone, suggesting that these diseases share causal mechanisms irrespective of IgE sensitization. IgE sensitization should be considered differently in monosensitized and polysensitized individuals. Allergic multimorbidities and IgE polysensitization are often associated with the persistence or severity of allergic diseases. Environmental exposures are relevant for the development of allergy-related diseases. To complement the population-based studies in children, MeDALL included mechanistic experimental animal studies and in vitro studies in humans. The integration of multimorbidities and polysensitization has resulted in a new classification framework of allergic diseases that could help to improve the understanding of genetic and epigenetic mechanisms of allergy as well as to better manage allergic diseases. Ethics and gender were considered. MeDALL has deployed translational activities within the EU agenda.

Are allergic multimorbidities and IgE polysensitization associated with the persistence or re-occurrence of foetal type 2 signalling? The MeDALL hypothesis.

Allergic diseases [asthma, rhinitis and atopic dermatitis (AD)] are complex. They are associated with allergen-specific IgE and nonallergic mechanisms that may coexist in the same patient. In addition, these diseases tend to cluster and patients present concomitant or consecutive diseases (multimorbidity). IgE sensitization should be considered as a quantitative trait. Important clinical and immunological differences exist between mono- and polysensitized subjects. Multimorbidities of allergic diseases share common causal mechanisms that are only partly IgE-mediated. Persistence of allergic diseases over time is associated with multimorbidity and/or IgE polysensitization. The importance of the family history of allergy may decrease with age. This review puts forward the hypothesis that allergic multimorbidities and IgE polysensitization are associated and related to the persistence or re-occurrence of foetal type 2 signalling. Asthma, rhinitis and AD are manifestations of a common systemic immune imbalance (mesodermal origin) with specific patterns of remodelling (ectodermal or endodermal origin). This study proposes a new classification of IgE-mediated allergic diseases that allows the definition of novel phenotypes to (i) better understand genetic and epigenetic mechanisms, (ii) better stratify allergic preschool children for prognosis and (iii) propose novel strategies of treatment and prevention.

IFNγ and perforin cooperate to control infection and prevent fatal pathology during persistent gammaherpesvirus infection in mice.

Infection with murine gammaherpesvirus 68 has become an accepted model for studying the virus/host interactions with regard to gammaherpesvirus infections. Previous studies using gene-deficient mice have revealed that neither IFNγ nor perforin is essential in controlling the outcome of infection or the virus load during chronic infection in C57BL/6 mice. However, pronounced multiorgan fibrosis and splenic atrophy are observed in mice lacking IFNγ or the IFNγ receptor. To study the interplay between perforin and IFNγ in controlling the virus-induced pathology and the viral load during chronic gammaherpesvirus infection, we infected IFNγ/perforin double-deficient C57BL/6 mice and followed the course of infection. While absence of perforin prevented the splenic atrophy in IFNγ-deficient mice, fibrosis did not disappear. Moreover, double-deficient mice developed extreme splenomegaly, were unable to control the viral load and displayed chronic immune activation. Thus, IFNγ and perforin act in concert to minimize pathology and control the viral load in mice chronically infected with MHV68. Furthermore, while certain aspect of the virus-induced pathology in IFNγ-deficient mice may be alleviated in double-deficient mice, other aspects are exaggerated, and the normal architecture of the spleen is completely destroyed. We believe that these findings add to the understanding of the virus/host interaction during chronic gammaherpes virus infection.

The ethical introduction of genome-based information and technologies into public health.

With the human genome project running from 1989 until its completion in 2003, and the incredible advances in sequencing technology and in bioinformatics during the last decade, there has been a shift towards an increase focus on studying common complex disorders which develop due to the interplay of many different genes as well as environmental factors. Although some susceptibility genes have been identified in some populations for disorders such as cancer, diabetes and cardiovascular diseases, the integration of this information into the health care system has proven to be much more problematic than for single gene disorders. Furthermore, with the 1000$ genome supposedly just around the corner, and whole genome sequencing gradually being integrated into research protocols as well as in the clinical context, there is a strong push for the uptake of additional genomic testing. Indeed, the advent of public health genomics, wherein genomics would be integrated in all aspects of health care and public health, should be taken seriously. Although laudable, these advances also bring with them a slew of ethical and social issues that challenge the normative frameworks used in clinical genetics until now. With this in mind, we highlight herein 5 principles that are used as a primer to discuss the ethical introduction of genome-based information and genome-based technologies into public health.

Long-term efficacy and safety comparison of liraglutide, glimepiride and placebo, all in combination with metformin in type 2 diabetes: 2-year results from the LEAD-2 study.

AIMS: To investigate efficacy and safety of dual therapy with liraglutide and metformin in comparison to glimepiride and metformin, and metformin monotherapy over 2 years in patients with type 2 diabetes. METHODS: In the 26-week the Liraglutide Effect and Action in Diabetes (LEAD)-2 core trial, patients (n = 1091) were randomized (2 : 2 : 2 : 1: 2) to liraglutide (0.6, 1.2 or 1.8 mg once-daily), placebo or glimepiride; all with metformin. Patients were enrolled if they were 18-80 years old with HbA1c 7.0-11.0% (previous monotherapy ≥3 months), or 7.0-10.0% (previous combination therapy ≥3 months), and body mass index ≤40 kg/m(2) . Patients completing the 26-week double-blinded phase could enter an 18-month open-label extension. RESULTS: HbA1c decreased significantly with liraglutide (0.4% with 0.6 mg, 0.6% with 1.2 and 1.8 mg) versus 0.3% increase with metformin monotherapy (p < 0.0001). HbA1c decrease with liraglutide was non-inferior versus 0.5% decrease with glimepiride. Liraglutide groups experienced significant weight loss (2.1, 3.0 and 2.9 kg with 0.6, 1.2 and 1.8 mg, respectively) compared to weight gain (0.7 kg) with glimepiride (p < 0.0001). Weight loss with liraglutide 1.2 and 1.8 mg was significantly greater than with metformin monotherapy (1.8 kg; p = 0.0185 and p = 0.0378 for 1.2 and 1.8 mg, respectively). The occurrence of minor hypoglycaemia was <5.0% in all liraglutide groups, significantly less than with glimepiride (24.0%; p < 0.0001). Liraglutide was well tolerated overall: gastrointestinal events were more common than with glimepiride or metformin monotherapy, but occurrence decreased with time. CONCLUSIONS: Liraglutide provided sustained glycaemic control over 2 years comparable to that provided by glimepiride. Liraglutide was well tolerated, and was associated with weight loss and a low rate of hypoglycaemia.

Cohabitation patterns among patients with severe psychiatric disorders in the entire Danish population.

BACKGROUND: Assortative mating has been demonstrated in mental disorders but the extent of cohabitation between patients with clinically diagnosed psychiatric disease has been poorly explored. Method We conducted a register-based study of all Danes between 18 and 70 years of age in a 13-year observational period, linking data on individuals' contacts with psychiatric services with data on individuals' cohabitation status. Two different Poisson regression analyses were performed: the first comparing the rates of commencing cohabitation with a psychiatric patient between individuals, depending on whether the individuals themselves had, or did not have, a psychiatric diagnosis; the second comparing the incidence rates of psychiatric diagnoses for individuals cohabitating with psychiatric patients with the similar rates for individuals living with unaffected cohabitants. RESULTS: In total, 159 929 (5.0%) out of 3 204 633 individuals were given a psychiatric diagnosis during the study period. Diagnosed individuals had an overall rate ratio (RR) of commencing cohabitation with a psychiatric patient of 1.95 [95% confidence interval (CI) 1.90-2.00] for women and 1.65 (95% CI 1.61-1.69) for men, when compared with unaffected individuals. The overall RR of receiving a psychiatric diagnosis while cohabitating with a psychiatric patient was 2.40 (95% CI 2.31-2.49) for women and 2.91 (95% CI 2.81-3.01) for men, when compared with those cohabitating with unaffected individuals. Individuals with schizophrenia and men with bipolar disorder had the highest RR of commencing cohabitation with a cohabitant with a similar diagnosis. CONCLUSIONS: Cohabitation among individuals with severe psychiatric disorders is increased. This has implications for research and for the clinical management of patients.