Diseases could be viewed as specific sets of phenotypes affecting one or several physiological systems. It has been shown that diseases whose components link to each other at the cellular level show higher comorbidity in the population. Systematically studying entire sets of comorbidities offer a complementary perspective of disease biology from traditional approaches. The overall aim of this project is to systematically study the associations between several diseases in the human population by building phenotypic disease networks (PDNs), with a focus on the known, strong comorbidities between 1) cardiovascular disease and psychiatric disorder, 2) cancer and psychiatric disorder, and 3) rare but complex diseases such as neurodegenerative diseases and psychiatric disorder. Importantly, we will contrast PDNs estimated in the UK Biobank with PDNs estimated using the entire Swedish population in our parallel study using the Swedish national registers.
Exploring comorbidities from a network perspective could help determine whether differences in the comorbidity patterns indicate differences in genetic background, biological processes, environmental factors, or health care quality provided for each population. This project together with our parallel study using the entire Swedish population will offer unique insights into the structure and mechanisms underlying comorbidities in different human populations and will potentially promote the prevention, diagnosis and treatment of diseases and the overall health throughout the society.