Using the population-based data sources in Iceland and the well-characterized AGES-Reykjavik cohort, our overarching aims are on exploring whether pre-diagnostic serum levels of 25-hydroxyvitamin D (25(OH)D) among older individuals living in Iceland were associated with survival after cancer diagnosis. We also wanted to assess the risk of being diagnosed with cancer in association with 25(OH)D levels. In this population living just south of the arctic circle, vitamin D levels largely depend on dietary- and supplemental sources.

Inclusion Criteria:

To be part of the AGES-Reykjavik Study, initiated between 2002 and 2006.

Exclusion Criteria:

Diagnosed with cancer at study entry

In 1967, all 30,795 men and women living in the capital area of Iceland and born between 1907 and 1935 were invited by the Icelandic Heart Association to join a prospective cohort study. Approximately 19,000 attended the clinic at least once and became participants of the Reykjavik Study. Subsequently, in 2002, a random sample of the cohort comprising 5,764 men and women who were still alive in Iceland and aged 66 to 96 years entered the Ages Gene/Environment Susceptibility (AGES) - Reykjavik Study (20). Serum 25(OH)D was measured in 5,519 of all 5,764 (96%) participants at study entry in year 2002 through 2006.