Serum cholesterol trajectories in the years prior to lymphoma diagnosis

Date of ISAC Approval: 
20/07/2018
Lay Summary: 
Lymphomas are a common group of cancers with poorly understood causes. There are several studies suggesting that lymphomas may be related to low cholesterol blood levels. However, this information often relies on relatively weak methodologies, such as basing results on a very small number of cholesterol measurements. On the other hand, the results of a recently published US study were the first to provide solid information on the relationship of blood cholesterol levels with the risk of suffering a lymphoma since it assessed a long period of time (10 years) before the diagnosis of lymphoma. Our proposed study intends to be the first to replicate these important findings while studying a different population (UK vs. US) and incorporating in the analyses important information about the patients that was missing in the original study (e.g., obesity, smoking, and alcohol use). The confirmation of lower blood cholesterol levels in the years before being diagnosed with a lymphoma could have potentially large public health implications given the severity and deaths related to lymphomas and the widespread availability and safety of blood cholesterol testing.
Technical Summary: 
Lymphomas are a heterogeneous group of malignancies that originate from lymphoid organs. There are several studies suggesting an association of hypocholesterolemia and lymphoma diagnosis. However, most studies have been based on only one baseline measurement of serum cholesterol. Recent research has suggested that cholesterol metabolism may be related to lymphomagenesis. One recently published paper with participation of an investigator of the proposed study was the first to provide information on the continuous relationship of cholesterol levels with lymphoma over the 10-year period leading to a diagnosis of lymphoma. This study used a large group of lymphoma patients identified from HMO claims data in the US. To replicate these important findings, we intend to conduct a matched case control study of a different population (UK vs. US) from a different type of secondary data (EMR vs. claims) while addressing confounders that were not available in the original study (e.g., BMI, alcohol use, smoking). There are potentially large public health implications in the confirmation of differential serum cholesterol levels between patients ultimately developing a lymphoma and healthy controls in the years before diagnosis.
Health Outcomes to be Measured: 
- first ever diagnosis of Lymphoma (with subtypes) - HDL cholesterol levels - total cholesterol levels - LDL cholesterol levels
Collaborators: 

Dr Joan Fortuny - Chief Investigator - RTI Health Solutions
Estel Plana Hortoneda - Collaborator - RTI Health Solutions
James Kaye - Collaborator - RTI Health Solutions
Dr Joan Fortuny - Corresponding Applicant - RTI Health Solutions
Rachel Weinrib - Collaborator - RTI Health Solutions

Linkages: 
HES Admitted;HES Admitted;HES Outpatient;PAT IDs;Patient IMD;Practice IMD (Standard)