Newer lower dose formulations are associated with an improved cardiovascular disease risk marker profile, which supports their use for longer periods and among older women. Epidemiologic studies of the newer formulations are limited. Without clinical information, an evaluation of the effects of more recent formulations on metabolic risk markers for cardiovascular disease is useful. In a large cross-sectional study, a reduction in the progestin dose and use of alternative progestins substantially reduced the proportion of oral contraceptive users with values associated with an increased risk of cardiovascular disease. No progression in metabolic changes was found by analyzing the effect of the duration of oral contraceptive use. The user's age interacted positively with the oral contraceptive--induced increase in serum triglyceride levels, but there was no interaction of age with the oral contraceptive's effect on oral glucose tolerance, glucose and insulin responses, low-density lipoprotein cholesterol, or high-density lipoprotein subfraction 2 cholesterol levels.
PIP: New lower dose oral contraceptive (OC) formulations which include those with the progestins desogestrel, norgestimate, and gestodene appear to reduce the risk of cardiovascular (CV) disease. This may lead to longer OC use and OC use in 35 year old women. Yet there have not been many clinical studies of the new formulations. Further research has not yet confirmed an effect of duration of older medium and high dose OC use or the effect of their past use. Researchers at the Wynn Institute for Metabolic Research in London, England believe that, regarding issues of currently used formulations, scientists should consider the results of studies of the older medium and high dose formulations since they have the only reliable data on long term OC safety. In fact, they examine the metabolic markers for CV disease (carbohydrate and lipid metabolic effects). Wynn researchers did not observe a progression in metabolic risk markers for CV disease in women who used OCs continuously for 2 years. Further no potentially adverse interaction existed between user's age and duration of OC use. In fact, user's age caused serum triglyceride levels to rise. Moreover user's age did not adversely affect oral glucose tolerance, glucose and insulin responses, low density lipoprotein subfraction 2 cholesterol levels. In addition, previous OC use left no apparent metabolic effects in former users. Results of studies done at the Wynn Institute suggest that 35 year old women may indeed be able to take current OC formulations as long as they regularly visit a health professional and have their serum lipid levels measured routinely.