New use of prescription drugs prior to a cancer diagnosis.

ABSTRACT:

Purpose

Cancers often have considerable induction periods. This confers a risk of reverse causation bias in studies of cancer risk associated with drug use, as early symptoms of a yet undiagnosed cancer might lead to drug treatment in the period leading up to the diagnosis. This bias can be alleviated by disregarding exposure for some time before the cancer diagnosis (lag time). We aimed at assessing the duration of lag time needed to avoid reverse causation bias.

Methods

We identified all Danish patients with incident cancer between 2000 and 2012 (n = 353 087). Incident use of prescription drugs was assessed prior to their cancer diagnosis as well as among population controls (n = 1 402 400). Analyses were conducted for all cancers and for breast, lung, colon and prostate c

SUBMITTER: Pottegard A 

PROVIDER: S-EPMC5299521 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature