['Several case-control studies have observed associations of implanted medical devices and certain connective-tissue and neurologic diseases. We reexamined these and other associations using cohort comparisons.', 'We compared the incidence of 52 diseases in several retrospective cohorts constructed from Medicare claims data. Six cohorts were defined by implantation of medical devices (silicone, metal bone or joint implants, breast implants, penile implants, pacemakers, artificial heart valves), and four comparison cohorts were defined by surgeries not involving implants.', 'We observed associations that were generally consistent with previous reports, including associations of bone and joint implants with connective-tissue diseases, and an association of penile implants with idiopathic progressive neuropathy. We also observed associations of breast implants and pacemakers with connective-tissue diseases.'] Does a retrospective cohort study of implanted medical devices and selected chronic diseases in Medicare claim data?