Multimorbidity Patterns in Elderly Primary Health Care Patients in a South Mediterranean European Region: A Cluster Analysis

Objective

The purpose of this study was to identify clusters of diagnoses in elderly patients with multimorbidity, attended in primary care.

Design

Cross-sectional study.

Setting

251 primary care centres in Catalonia, Spain.

Participants

Individuals older than 64 years registered with participating practices.

Main outcome measures

Multimorbidity, defined as the coexistence of 2 or more ICD-10 disease categories in the electronic health record. Using hierarchical cluster analysis, multimorbidity clusters were identified by sex and age group (65–79 and ≥80 years).

Results

322,328 patients with multimorbidity were included in the analysis (mean age, 75.4 years [Standard deviation, SD: 7.4], 57.4% women; mean of 7.9 diagnoses [SD: 3.9]). For both men and women, the first cluster in both age groups included the same two diagnoses: Hypertensive diseases and Metabolic disorders. The second cluster contained three diagnoses of the musculoskeletal system in the 65- to 79-year-old group, and five diseases coincided in the ≥80 age group: varicose veins of the lower limbs, senile cataract, dorsalgia, functional intestinal disorders and shoulder lesions. The greatest overlap (54.5%) between the three most common diagnoses was observed in women aged 65–79 years.

Conclusion

This cluster analysis of elderly primary care patients with multimorbidity, revealed a single cluster of circulatory-metabolic diseases that were the most prevalent in both age groups and sex, and a cluster of second-most prevalent diagnoses that included musculoskeletal diseases. Clusters unknown to date have been identified. The clusters identified should be considered when developing clinical guidance for this population.     

Three‐dimensional reconstruction of corticospinal tract using one‐photon confocal microscopy acquisition allows detection of axonal disruption in spinal cord injury

The principal motor tract involved in mammalian locomotor activities is known as the corticospinal tract (CST), which starts in the brain motor cortex (upper motor neuron), extends its axons across the brain to brainstem and finally reaches different regions of spinal cord, contacting the lower motor neurons. Visualization of the CST is essential to carry out studies in different kinds of pathologies such as spinal cord injury or multiple sclerosis. At present, most studies of axon structure and/or integrity that involve histological tissue sectioning present the problem of finding the region where the CST is predominant. To solve this problem, one could use a novel technique to make the tissues transparent and observe them directly without histological sectioning. However, the disadvantage of this procedure is the need of costly and non‐conventional equipment, such as two‐photon fluorescence microscopy or ultramicroscopy to perform the image acquisition. Here, we show that labeling the CST with FluoroRuby in the motor cortex and then performing the clearing technique, the z‐acquisition of the entire CST in unsectioned tissue followed by three‐dimensional reconstruction can be carried out by standard one‐photon confocal microscopy, with yields similar to those obtained by two‐photon microscopy. In addition, we present an example of the application of this method in a spinal cord injury model, where the disruption of CST is shown at the lesion site.

     

Mitochondrial inner membrane permeabilisation enables mtDNA release during apoptosis

During apoptosis, pro‐apoptotic BAX and BAK are activated, causing mitochondrial outer membrane permeabilisation (MOMP), caspase activation and cell death. However, even in the absence of caspase activity, cells usually die following MOMP. Such caspase‐independent cell death is accompanied by inflammation that requires mitochondrial DNA (mtDNA) activation of cGAS‐STING signalling. Because the mitochondrial inner membrane is thought to remain intact during apoptosis, we sought to address how matrix mtDNA could activate the cytosolic cGAS‐STING signalling pathway. Using super‐resolution imaging, we show that mtDNA is efficiently released from mitochondria following MOMP. In a temporal manner, we find that following MOMP, BAX/BAK‐mediated mitochondrial outer membrane pores gradually widen. This allows extrusion of the mitochondrial inner membrane into the cytosol whereupon it permeablises allowing mtDNA release. Our data demonstrate that mitochondrial inner membrane permeabilisation (MIMP) can occur during cell death following BAX/BAK‐dependent MOMP. Importantly, by enabling the cytosolic release of mtDNA, inner membrane permeabilisation underpins the immunogenic effects of caspase‐independent cell death.     

Characterisation of a K390R ITK Kinase Dead Transgenic Mouse – Implications for ITK as a Therapeutic Target

Interleukin-2 inducible tyrosine kinase (ITK) is expressed in T cells and plays a critical role in signalling through the T cell receptor. Evidence, mainly from knockout mice, has suggested that ITK plays a particularly important function in Th2 cells and this has prompted significant efforts to discover ITK inhibitors for the treatment of allergic disease. However, ITK is known to have functions outside of its kinase domain and in general kinase knockouts are often not good models for the behaviour of small molecule inhibitors. Consequently we have developed a transgenic mouse where the wild type Itk allele has been replaced by a kinase dead Itk allele containing an inactivating K390R point mutation (Itk-KD mice). We have characterised the immune phenotype of these naive mice and their responses to airway inflammation. Unlike Itk knockout (Itk^−/−) mice, T-cells from Itk-KD mice can polymerise actin in response to CD3 activation. The lymph nodes from Itk-KD mice showed more prominent germinal centres than wild type mice and serum antibody levels were significantly abnormal. Unlike the Itk^−/−, γδ T cells in the spleens of the Itk-KD mice had an impaired ability to secrete Th2 cytokines in response to anti-CD3 stimulation whilst the expression of ICOS was not significantly different to wild type. However ICOS expression is markedly increased on αβCD3⁺ cells from the spleens of naïve Itk-KD compared to WT mice. The Itk-KD mice were largely protected from inflammatory symptoms in an Ovalbumin model of airway inflammation. Consequently, our studies have revealed many similarities but some differences between Itk^−/−and Itk-KD transgenic mice. The abnormal antibody response and enhanced ICOS expression on CD3+ cells has implications for the consideration of ITK as a therapeutic target.     

The map position of Sym-plasmid regions expressed in the bacterial and endosymbiotic form of Rhizobium leguminosarum

The Sym plasmid of Rhizobium leguminosarum, which is called pRle1001a, was found to be transcribed in both cultured bacteria and in bacteroids isolated from mature pea root nodules. The transcribed regions were localized on a restriction endonuclease map of this plasmid. None of the areas expressed in the endosymbiotic form overlapped with the one that is expressed in stationary phase cultures of the bacteria. One relatively large region that is actively transcribed in nitrogen-fixing bacteroids included the DNA homologous to the structural nif genes D and H of Klebsiella pneumoniae. This transcribed segment is also highly conserved in the Sym plasmid of R. trifolii 5 and a plasmid of R. phaseoli 3622, which carries nif genes. It is assumed that this region carries the nif operon.     

Immunoregulation by T cells. I. Characterization of the IEk-specific Lbd self-reactive T cell clone that helps, suppresses and contrasupresses B cell responses

This paper describes an L3T4+, Lyt-2- cloned T cell line of CBA/N origin that is specific for IEk-encoded products. Splenic dendritic cells are the predominant stimulatory populations for Lbd cells, being approximately 100 times more effective than large activated B cells. Small B cells and T cells are nonstimulatory. Lbd cells help large B cells to make polyclonal antibody responses, but are unable to activate small B cells and to replace antigen-specific helper T cells in T cell-dependent responses to phosphorylcholine or sheep red blood cells. In the presence of antigen-specific helper T cells, Lbd can amplify, suppress, or contrasuppress T cell function, depending on the type and relative ratios of antigen-reactive cells. We explain our findings as a consequence of the self reactivity among helper T cells.     

Expression level polymorphisms: heritable traits shaping natural variation

Natural accessions of many species harbor a wealth of genetic variation visible in a large array of phenotypes. Although expression level polymorphisms (ELPs) in several genes have been shown to contribute to variation in diverse traits, their general impact on adaptive variation has likely been underestimated. At present, ELPs have predominantly been correlated to quantitative trait loci (eQTLs) that occupy central hubs in signaling networks, which pleiotropically affect numerous traits. To increase the sensitivity of detecting minor effect eQTLs or those that act in a trait-specific manner, we emphasize the need for more systematic approaches. This requires, but is not limited to, refining experimental designs such as reduction of tissue complexity and combinatorial methods including a priori defined networks.     

HPV16 Seropositivity and Subsequent HPV16 Infection Risk in a Naturally Infected Population: Comparison of Serological Assays

Background

Several serological assays have been developed to detect antibodies elicited against infections with oncogenic human papillomavirus (HPV) type 16. The association between antibody levels measured by various assays and subsequent HPV infection risk may differ. We compared HPV16-specific antibody levels previously measured by a virus-like particle (VLP)-based direct enzyme-linked immunoassay (ELISA) with levels measured by additional assays and evaluated the protection against HPV16 infection conferred at different levels of the assays.

Methodology/Principal Findings

Replicate enrollment serum aliquots from 388 unvaccinated women in the control arm of the Costa Rica HPV vaccine trial were measured for HPV16 seropositivity using three serological assays: a VLP-based direct ELISA; a VLP-based competitive Luminex immunoassay (cLIA); and a secreted alkaline phosphatase protein neutralization assay (SEAP-NA). We assessed the association of assay seropositivity and risk of subsequent HPV16 infection over four years of follow-up by calculating sampling-adjusted odds ratios (OR) and HPV16 seropositivity based on standard cutoff from the cLIA was significantly associated with protection from subsequent HPV16 infection (OR = 0.48, CI = 0.27–0.86, compared with seronegatives). Compared with seronegatives, the highest seropositive tertile antibody levels from the direct ELISA (OR = 0.53, CI = 0.28–0.90) as well as the SEAP-NA (OR = 0.20, CI = 0.06, 0.64) were also significantly associated with protection from HPV16 infection.

Conclusions/Significance

Enrollment HPV16 seropositivity by any of the three serological assays evaluated was associated with protection from subsequent infection, although cutoffs for immune protection were different. We defined the assays and seropositivity levels after natural infection that better measure and translate to protective immunity.     

Antidepressant Utilization and Suicide in Europe: An Ecological Multi-National Study

Background

Research concerning the association between use of antidepressants and incidence of suicide has yielded inconsistent results and is the subject of considerable controversy. The first aim is to describe trends in the use of antidepressants and rates of suicide in Europe, adjusted for gross domestic product, alcohol consumption, unemployment, and divorce. The second aim is to explore if any observed reduction in the rate of suicide in different European countries preceded the trend for increased use of antidepressants.

Methods

Data were obtained for 29 European countries between 1980 and 2009. Pearson correlations were used to explore the direction and magnitude of associations. Generalized linear mixed models and Poisson regression distribution were used to clarify the effects of antidepressants on suicide rates, while an autoregressive adjusted model was used to test the interaction between antidepressant utilization and suicide over two time periods: 1980–1994 and 1995–2009.

Findings

An inverse correlation was observed in all countries between recorded Standardised Death Rate (SDR) for suicide and antidepressant Defined Daily Dosage (DDD), with the exception of Portugal. Variability was marked in the association between suicide and alcohol, unemployment and divorce, with countries depicting either a positive or a negative correlation with the SDR for suicide. Every unit increase in DDD of an antidepressant per 1000 people per day, adjusted for these confounding factors, reduces the SDR by 0.088. The correlation between DDD and suicide related SDR was negative in both time periods considered, albeit more pronounced between 1980 and 1994.

Conclusions

Suicide rates have tended to decrease more in European countries where there has been a greater increase in the use of antidepressants. These findings underline the importance of the appropriate use of antidepressants as part of routine care for people diagnosed with depression, therefore reducing the risk of suicide.