Retrospective cross-sectional analysis of concurrent VTE diagnosis in hospitalised socially excluded individuals in Ireland

OBJECTIVE

Social exclusion (such as that experienced by people who are homeless, incarcerated or use drugs) increases morbidity across a range of diseases but is poorly captured in routine data sets. The aim of this study was to use a novel composite variable in a national-level hospital usage dataset to identify social exclusion and to determine whether social exclusion is associated with concurrent venous thromboembolism (VTE) in hospitalised patients in Ireland. Identifying and characterising this association in people who are socially excluded will inform VTE prevention and treatment strategies.

DESIGN

Retrospective cross-sectional study.

SETTING

Irish Hospital Inpatient Enquiry (HIPE) system, which collects diagnostic information by International Classification of Diseases Tenth Revision code on all hospital admission episodes in the Ireland.

PARTICIPANTS

All hospital admission episodes involving a VTE diagnosis (in a primary 'Dx 1' or secondary 'Dx 2-30' coding position) during a 12-month period in the Ireland were identified from consolidated, national-level datasets derived from the Irish HIPE system. Social exclusion was defined as the presence of one or more indicators of homelessness, drug use, incarceration, health hazards due to socioeconomic status or episodes of healthcare terminated prematurely.

RESULTS

Of 5701 admission episodes involving a VTE diagnosis (in a primary or secondary position) during the study period, 271 (4.8%) related to an individual affected by social exclusion. Among hospitalised individuals identified as being socially excluded based on the novel composite variable, the likelihood of having a concurrent VTE diagnosis was over twofold greater than that observed in the general population (OR 2.14, 95% CI 1.79 to 2.26; p<0.001).

CONCLUSION

These data suggest that VTE (primary and secondary) is over-represented in hospitalised socially excluded persons in Ireland and that the development of strategies to address this potentially life-threatening accompanying condition in this vulnerable patient group must be prioritised.

Overexpression of connexin 43 in skeletal myoblasts: Relevance to cell transplantation to the heart

OBJECTIVE

Skeletal myoblast transplantation is a promising strategy for treating end-stage heart failure. One potential problem in the development of functional, synchronously contracting grafts is the degree of intercellular communication between grafted myoblasts and host cardiomyocytes. Thus it is expected that enhancement of intercellular gap junction formation would result in improved efficiency of skeletal myoblast transplantation. In this study we investigated whether myoblasts overexpressing connexin 43, a major cardiac gap junction protein, would enhance this intercellular communication.

METHODS AND RESULTS

L6 rat skeletal myoblast cell lines overexpressing connexin 43 were generated by means of gene transfection and clonal selection. Connexin 43 overexpression of these myoblasts, which continued both in undifferentiated and differentiated states (up to 17-fold greater protein level in comparison with control-transfected myoblasts, as measured with Western blotting), was observed on cell surfaces where gap junctions should exist. Both dye microinjection and scrape loading with fluorescent dyes showed enhancement in intercellular dye transfer between connexin 43-transfected myoblasts compared with that found in control-transfected cells. Morphologically, these myoblasts fused and differentiated into multinucleated myotubes more rapidly, demonstrating a higher level of cellular creatine kinase activity as a marker of myogenic differentiation throughout the culture period compared with that of control-transfected myoblasts.

CONCLUSIONS

We have generated connexin 43-overexpressing skeletal myoblast cell lines that resulted in improved formation of functional intercellular gap junctions, which could be relevant to synchronous contraction of grafted myoblasts in the heart. In addition, these cells demonstrated more rapid differentiation, which would also be advantageous in a graft for transplantation to the heart.