The study was ancillary to the multicenter Study of Osteoporotic Fractures (SOF), a prospective study on risk factors for hip and wrist fractures supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases. The cross-sectional study involved a sample of subjects at the Pittsburgh Center. The distribution and interrelationships of lipoproteins and apoproteins were described as were their relationships to age, years since menopause, type of menopause, and lifestyle factors such as physical activity, alcohol consumption, cigarette smoking, obesity, and use of estrogens/progestins. The frequency of phenotypes of the polymorphisms of apoprotein A-IV and E were examined to determine whether these phenotypes were associated with specific patterns of lipo- and apoproteins. The hypothesis was tested that the degree to which lifestyle characteristics explain the variability in lipoproteins and apoproteins depended on the genetic makeup of the individual.