NCI Study Finds No Conclusive Evidence that Breast Implants Affect Development of Connective Tissue Disorders
Researchers at the National Cancer Institute (NCI), part of the National Institutes of Health, found no convincing evidence that breast
implants have an effect on the development of subsequent connective tissue disorders (CTDs). The results are reported in the October 1, 2004
issue of the American Journal of Epidemiology.*
The researchers used data from one of the largest studies on the long-term health effects of breast implants. A large number of patients
reported CTDs, but when their records were examined by two board-certified rheumatologists, few cases were considered likely.
In 1992, the U.S. Congress asked the National Institutes of Health to investigate the long-term safety of breast implants. Scientists at
NCI, led by Louise Brinton, Ph.D. in the Division of Cancer Epidemiology and Genetics, examined the medical records of 13,500 women who had
cosmetic breast implant surgery before 1989 and 4,000 women similar in age who had other types of plastic surgery. Although it was not the
original intent of the study, the available information provided investigators with an opportunity to study the risk of CTDs in this
population.
For some time, there has been uncertainty regarding whether breast implants might be associated with the development of certain CTDs. Most
of the previous studies on this issue had small sample sizes, limited time to follow the clinical outcomes of the women after their surgeries,
and imprecise information on either implant status or disease outcomes. This study included a large population of women with breast implants,
detailed information on their implants, patients' answers to questions about their disease experience and other health characteristics, and
long-term follow-up of up to 13 years.
Four major CTDs (rheumatoid arthritis, systemic lupus erythematosus, scleroderma, and Sjögren's syndrome) were more commonly reported by
breast implant patients, with an approximate two-fold increase in risk. Attempts were made to review the medical records for three of these
conditions where there were elevations in reported risks both before and after 1992, the time when breast implants were deemed investigational
by the U.S. Food and Drug Administration. Only 30 percent to 40 percent of the medical records could be obtained. When these records were
blindly reviewed by two expert rheumatologists, only 17 percent to 30 percent of the diagnoses were considered 'likely.' When only likely
diagnoses were considered, the excess risk of CTDs became statistically non-significant, meaning they could have happened by chance. Further,
the small number of confirmed cases of scleroderma and Sjogren's syndrome made interpretation of the risks difficult. The researchers also
were unable to assess the existence of any new CTD specific to implant patients.
To further clarify the relationship of implants to the risk of CTDs, future research should include clinical examinations of patients using
defined diagnostic criteria for these disorders. Given the rarity of conditions such as scleroderma and Sjögren's syndrome, a study would need
to be very large to fully clarify the association between breast implants and these disorders.
# # #
For more information about cancer, visit the NCI Web site at http://www.cancer.gov or call NCI's Cancer
Information Service at 1-800-4-CANCER (1-800-422-6237).
*Brinton LA, Buckley LM, Dvorkina O, et al. Risk of Connective tissue disorders among breast implant patients. Am J Epidemiology, Oct
2004; 160. (Released online September 21, 2004)
Back to Top |