Cohabitation Patterns and Incidence of Known and Suspected Sexually Transmitted Diseases

Study Overview
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Brief Summary
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The number of infectious agents associated with risks of malignant hematologic diseases is non-negligible and include both viruses and bacteria. The various organisms affect cancer risk either directly by transforming susceptible cells, through chronic antigenic stimulation or by hampering immune function in other ways conducive of cancer development. Suspicion of an infectious cancer origin may arise because of clustering with other conditions (e.g. immune deficiency), specific environments or settings (e.g. geographic locales) or with exposures (e.g. blood transfusions). In this context, relatively few studies have addressed clustering of diseases among spouses to generate hypotheses about the relative contributions of environmental and genetic factors to the risk of individual cancer types. As a prelude to such an exercise aiming specifically at malignant hematologic diseases, we will test an algorithm characterising cohabitation patterns in the Danish population to assess the risk of sexually transmitted diseases in analyses of register data. Such information will also be relevant to current guidelines for blood donor deferral policies. Specifically, because of the so-called precautionary principle all blood donations are extensively tested for infectious agents and transfusion of blood now carries an extremely low risk of transmission of HIV, hepatitis B and C. The residual risk of HIV transmission in Denmark is estimated to 1:10,000,000 transfusions. However, several deferral criteria have existed for years without studies to prove their relevance. Aim: To compare the incidence of both known and suspected sexually transmitted diseases between different cohabitation patterns in the Danish population. Perspectives: The study results can be used to leverage changes in deferral rules in the Danish blood banks to accommodate strong wishes from stakeholders to avoid the perceived discrimination of various minorities. The study can thus have important ethical and political consequences.

Official Title
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Cohabitation Patterns and Incidence of Known and Suspected Sexually Transmitted Diseases

Conditions
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Cohabitation Patterns, Sexually Transmitted Diseases

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All citizens in Denmark Exclusion Criteria: Institutionalized individuals

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sexually transmitted diseases | The diseases will be identified by using the Danish National Patient Register (NPR). Diagnostic information is based on the International Classification of Diseases, Eight and Tenth Revision (ICD-8 and ICD-10). | 1977 - 2018 | 
| HIV, syphilis, and gonorrhea | HIV, syphilis, and gonorrhea will be identified by registration in the Mandatory disease notification system administrated by Statens Serums Institut (SSI), Denmark. | 2005 - 2018 |