Higher levels of cholesterol have been seen to increase risk of DCS in SCUBA diving in several studies.
A 1988 study found that higher levels of cholesterol resulted in increased bubbling when decompressing to altitude. A 1986 study found a higher incidence of venous gas embolism in subjects with greater levels of total cholesterol and HDL cholesterol (ironically, the "good cholesterol"). In 2004, researchers found a correlation between brain lesions and cholesterol in asymptomatic professional divers.
Freediving does not have the same risk of DCS as SCUBA, unless exersions to depth are repeated enough to accumulate a certain amount of "bottom time." That said, there are other stresses on the heart and circulation that come from holding your breath that might be exacerbated by a high level of cholesterol. I could find no studies specifically looking at this, but if your cholesterol level is high enough at your age that your physician places you in a higher risk category for CAD, then you might consider avoiding freediving.
Cameron