Women with silicone breast implants may be at increased risk for several rare adverse events, according to the first comprehensive study of long-term outcomes since the implants were reapproved. The findings—and an editorial from the US Food and Drug Administration expressing concerns about the controversial data—were published in Annals of Surgery.
In the early 1990s, the FDA prohibited use of silicone breast implants following public concerns about health risks. However, subsequent research found no link between implants and the cited diseases. In 2006, the FDA approved sales of silicone implant by two manufacturers—Allergan and Mentor Corp—with the stipulation that they both conduct large post-approval studies (LPAS) to monitor long-term health and safety outcomes.
The LPAS included 99,903 total patients; Allergan enrolled 41,342 patients with silicone implants and 15,646 with saline and Mentor enrolled 41,975 patients with silicone and 1030 with saline. The majority of patients received silicone implants for primary augmentation (56%). The primary outcome of the research was rare harm, including cumulative trauma disorder (CTD), neurological, autoimmune disease, cancer, self-harm/wellbeing/satisfaction, and reproduction. Secondary outcomes included imaging surveillance, local complications and reoperation.
The authors found that women who had silicone breast implants were at increased risk of several harms compared to the general public. Using standardized incidence ratios (SIR), women with silicone were found to be approximately eight times more likely to be diagnosed with Sjogren’s syndrome (SIR: 8.14, 95% CI 6.24-10.44), P < 0.001); seven times likelier to be diagnosed with scleroderma (SIR: 7.00, 95% CI 5.12-9.34, P< 0.001); and almost six times likelier to be diagnosed with rheumatoid arthritis (SIR: 5.96, 95% CI: 5.35-6.62, P<0.001).
Women with the implants were also at a higher risk for melanoma (SIR: 3.71, 95% CI 2.87-4.73, P< 0.001). In terms of reproduction, women with silicone implants did not have a significantly higher risk for miscarriage but they were at higher risk for stillbirth (SIR: 4.50, 95% CI 3.59-5.56, P < 0.001). Unlike in previous studies, the authors did not find an increased risk of suicide among women with silicone implants.
When the authors compared silicone and saline implants, they found that silicone was linked to a higher risk of surgical complications. These included an increased risk of capsular contracture for silicone compared to saline (5.0% versus 2.8%, respectively) and higher rates of short-term reoperation for silicone (6.5% versus 3.4% at 2 years, respectively).
While certain harms and adverse outcomes appear to be more frequent with silicone implants, the authors noted several limitations to the study and emphasized that the results are inconclusive as a result. In the editorial, the FDA said, the researchers “failed to account for methodologic differences between studies, inconsistencies in the data, differential loss to follow-up, confounding and other potential sources of bias.” Noting that “the report’s conclusions should be viewed with caution,” the agency said that a public meeting of its Medical Devices Advisory Committee will be held in 2019 to promote public dialogue and discussion about currently available scientific information on breast implants.