Annual rhythm in filgrastim use in southeast Florida.

e20697 Background: Circadian, seasonal and annual temporal organization characterizes earth-evolved life forms. Cellular proliferation in human bone marrow shares this temporal organization. Careful clinical trials have documented that bone marrow damage from a range of cytotoxic anti-cancer drugs is predictably greater and lesser when these drugs are given at specific times of day and seasons of the year to human beings with cancer. Filgrastim is a human growth factor, which is given to stimulate the production of neutrophils that have been depressed to low levels by cancer chemotherapy, in order to prevent infectious complications. We hypothesized that administration of filgrastim, stimulated by dangerously low neutrophil counts, would be initiated non-randomly with reproducible seasonality and annual rhythmicity. Methods: All claims from contracted healthplans submitted by oncologists in southeast Florida were tabulated by month of service date, during the calendar years of 2010, 2011, and 2012 (n=2,50...