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Etiology

Silicone breast implants did not increase risk for connective tissue diseases or related symptoms

ACP J Club. 1995 Nov-Dec;123:76. doi:10.7326/ACPJC-1995-123-3-076


Source Citation

Sánchez-Guerrero J, Colditz GA, Karlson EW, et al. Silicone breast implants and the risk of connective-tissue diseases and symptoms. N Engl J Med. 1995 Jun 22;332:1666-70.


Abstract

Objective

To determine whether an association exists between silicone breast implants and connective tissue diseases (CTD) or signs or symptoms of CTD.

Design

14-year cohort analytic study of women in the Nurses' Health Study.

Setting

U.S. community-based study.

Participants

Women aged 30 to 55 years responded to biennial questionnaires between 1976 and 1992, and 109 750 were still participating in 1992. Questions about CTD were included after 1981. The 1992 questionnaire contained questions about breast implant surgery and about silicone, paraffin, and collagen injections. A supplementary questionnaire was sent to women who reported having received implants, and a screening questionnaire was sent to women who reported having any rheumatic or musculoskeletal disorders or CTD. Women who reported having breast implants after May 1990 or having CTD before 1976 or after May 1990 were excluded from the analysis. 87 501 women were eligible for follow-up.

Assessment of risk factors

Type of implant (silicone-gel-filled, saline-filled, double-lumen, or polyurethane-coated) was noted. Researchers entering data on implant history were blinded to medical history, and rheumatologists who reviewed medical records for CTD information were blinded to exposure.

Main outcome measure

Age-adjusted relative risk (RR) for CTD.

Main results

1183 women reported having a breast implant, with a mean follow-up after surgery of 10 years. CTDs were confirmed in 516 women. 3 women with CTD (all had rheumatoid arthritis) had breast implants (1 silicone-gel-filled, 1 double-lumen, and 1 saline-filled). The RR for any CTD among women with any type of breast implant was 0.6 (95% CI 0.2 to 2.0). For women with silicone-gel-filled implants, the RR was 0.3 (CI 0.0 to 2.0). Among 5087 women with self-reported CTD or rheumatic disorders, the RR for any CTD in women with any breast implant was 0.7 (CI 0.5 to 1.0), and in women with silicone-gel-filled implants it was 0.6 (CI 0.4 to 0.9). The age-adjusted RR for self-reported signs or symptoms of CTD in women with any breast implant was 1.5 (CI 0.7 to 2.2).

Conclusion

No association was found between silicone breast implants and diagnosed CTD or signs or symptoms of CTD.

Source of funding: National Institutes of Health.

For article reprint: Dr. M. Liang, Brigham and Women's Hospital, Department of Rheumatology and Immunology, 75 Francis Street, Boston, MA 02115, USA.


Commentary

Although numerous anecdotal case reports suggest an association between silicone breast implants and CTD, controlled epidemiologic studies do not confirm that this association exists. While interpreting these discrepant findings, one should keep in mind the strengths and limitations of the controlled studies and the fact that anecdotal case reports contribute virtually no information that bears on the question of causation (1).

Using a cohort study design, Sánchez-Guerrero and colleagues did not find an association between silicone breast implants and either CTD or related symptoms among registered nurses in the United States who were followed since 1976. The strengths of this work include the controlled study design, the large national sampling frame, the validation of breast implant information, and the careful case-identification techniques. Despite these meticulous research methods, this study could not rule out a small increase in risk for CTD or CTD symptoms. Nonetheless, the findings of this study are consistent with those of another large cohort study (2) and those of at least 5 other controlled studies that examined this question (3-7).

These data suggest that all women who develop CTD or CTD symptoms should be evaluated and managed in the same manner, whether or not they have breast implants.

Sherine Gabriel, MD
Mayo ClinicRochester, Minnesota, USA


References

1. Collins N, Eckhart C, Chalew GN.Cause. In: Fletcher RH, Fletcher SW, Wagner EH, eds. Clinical Epidemiology. The Essentials. 2d ed. Baltimore: Williams & Wilkins;1988:208-25.

2. Gabriel SE, O'Fallon WM, Kurland LT, et al. Risk of connective-tissue diseases and other disorders after breast implantation. N Engl J Med. 1994;330:1697-702.

3. Dugowson CE, Daling J, Koepsell TD, Voight L, Nelson JL. Silicone breast implants and risk for rheumatoid arthritis [Abstract]. Arthritis Rheum. 1992;35:S66.

4. Hochberg MC, Perlmutter DL, White B, et al. The association of augmentation mammoplasty with systemic sclerosis: Results from a multicenter case-control study [Abstract]. Arthritis Rheum. 1994;37:S369.

5. Strom BL, Reidenberg MM, Freundlich B, Schinnar R. Breast silicone implants and risk of systemic lupus erythematosus. J Clin Epidemiol. 1994;47:1211-4.

6. Englert HJ, Brooks P. Scleroderma and augmentation mammoplasty—a causal relationship? Aust N Z J Med. 1994;24:74-80.

7. Burns CG. The epidemiology of systemic sclerosis. A population-based case-control study. Ann Arbor, MI: University of Michigan, 1994. PhD dissertation.