Silicone breast implants: epidemiological evidence of sequelae.
Skeptics may certainly find fault with the third study (the only one to report a significant finding) or with all or any of the statistics described. But few could argue, after examining these studies, that the relative risk for a known and well-defined connective tissue disease is likely greater than 2. Another possibility has been raised, one that calls to mind other difficult-to-study syndromes linked to exposures. In a study addressing Gulf War syndrome, signs and symptoms were often mentioned that proved difficult to describe systematically and therefore difficult to study. What if a suspected silicone exposure syndrome were so mild and transient that it did not warrant a physician visit (as in the Mayo Clinic study). receive a diagnosis (as in the Nurses' Health Study), or require admission to a hospital (as in the Danish and Swedish studies)? And if such a disorder were, in fact, mild and transient, should it merit the concern that has been shown and the compensation that has been awarded in the silicone implant litigation cases to date? We suggest that neither a well-described disorder with a relative risk of less than 2 nor a transient and mild disorder seems compatible with the number of litigants over silicone implants and the apparent seriousness of their complaints. Some 400,000 women joined in one class action suit for damages, and 170,000 joined in another. Even if there had been 2 million implants undertaken in the United States over the 3 decades in which implant surgery has been practiced (and some estimates put the number closer to 1 million), there is no conceivable way in which a relative risk of 2 or 3 (or even 4) for each of the rare syndromes reported could explain so many exposed women being affected. At most, 2200 out of 2 million unexposed women would be expected to have had any one of the listed forms of connective tissue disorders, most of which are very rare. Doubling the risk among the exposed population yields 4400, and increasing the risk 20-fold produces 44,000. At this rate, there is no way in which 400,000 litigants could all be affected. Extensions of the already-completed studies are ongoing, at least 1 of which is government funded; apparently it is thought in the United States (though not in the United Kingdom or elsewhere) that there is still room for reasonable doubt as to the supposed causal relationships. But if epidemiology is invoked in the interest of public health to prevent the many uses of silicone, the weight of the evidence abstracted here supports the inference that silicone breast implants have not been proved guilty of causing connective tissue disorders. (+info)
Meta-analyses of the relation between silicone breast implants and the risk of connective-tissue diseases.
BACKGROUND: The postulated relation between silicone breast implants and the risk of connective-tissue and autoimmune diseases has generated intense medical and legal interest during the past decade. The salience of the issue persists, despite the fact that a great deal of research has been conducted on this subject. To provide a stronger quantitative basis for addressing the postulated relation, we applied several techniques of meta-analysis that combine, compare, and summarize the results of existing relevant studies. METHODS: We searched data bases and reviewed citations in relevant articles to identify studies that met prestated inclusion criteria. Nine cohort studies, nine case-control studies, and two cross-sectional studies were included in our meta-analyses. We conducted meta-analyses of the results of these studies, both with and without adjustment for confounding factors, and a separate analysis restricted to studies of silicone-gel-filled breast implants. Finally, we estimated the annual number of new cases of connective-tissue disease that could be attributed to breast implants. RESULTS: There was no evidence that breast implants were associated with a significant increase in the summary adjusted relative risk of individual connective-tissue diseases (rheumatoid arthritis, 1.04 [95 percent confidence interval, 0.72 to 1.51]; systemic lupus erythematosus, 0.65 [95 percent confidence interval, 0.35 to 1.23]; scleroderma or systemic sclerosis, 1.01 [95 percent confidence interval, 0.59 to 1.73]; and Sjogren's syndrome, 1.42 [95 percent confidence interval, 0.65 to 3.11]); all definite connective-tissue diseases combined (0.80; 95 percent confidence interval, 0.62 to 1.04); or other autoimmune or rheumatic conditions (0.96; 95 percent confidence interval, 0.74 to 1.25). Nor was there evidence of significantly increased risk in the unadjusted analyses or in the analysis restricted to silicone-gel-filled implants. CONCLUSIONS: On the basis of our meta-analyses, there was no evidence of an association between breast implants in general, or silicone-gel-filled breast implants specifically, and any of the individual connective-tissue diseases, all definite connective-tissue diseases combined, or other autoimmune or rheumatic conditions. From a public health perspective, breast implants appear to have a minimal effect on the number of women in whom connective-tissue diseases develop, and the elimination of implants would not be likely to reduce the incidence of connective-tissue diseases. (+info)
Induction of hypergammaglobulinemia and macrophage activation by silicone gels and oils in female A.SW mice.
Although most published epidemiological studies have found little evidence of systemic autoimmune disease associated with silicone breast implants, there still remains a question of whether silicones can cause local and/or systemic immune dysfunction. This study further investigates the effects of silicones on autoantibody and immunoglobulin production and macrophage activation in female A.SW mice. Sixty mice were divided among four treatment groups receiving a 0.5-ml intraperitoneal injection of either phosphate-buffered saline (PBS), pristane, silicone gel, or silicone oil. Test bleeds were taken periodically for 6 months. In contrast to pristane, neither silicone gel nor silicone oil induced lupus-associated antinuclear autoantibodies (immunoglobulin G [IgG] anti-nRNP/Sm, Su, and ribosomal P) or lupus nephritis. However, serum IgM became elevated persistently within 1 month of silicone gel or silicone oil administration. Also, the level of IgG3 was clearly elevated in silicone oil-treated mice. In contrast, IgG1, IgG2a, and IgG2b levels were not affected greatly by either silicone gel or oil. Furthermore, peritoneal macrophages from silicone- and pristane-treated mice produced higher levels of interleukin-1beta (IL-1beta) and IL-6 than those from PBS-treated mice after lipopolysaccharide stimulation. These results suggest that silicone gels and oils are capable of inducing hypergammaglobulinemia and activating macrophages in female A.SW mice. (+info)
Silicone breast implants: lessons from a saga.
In the following eleven lessons learned from the silicone breast implant saga in the United States are listed. Some Lessons From The Saga Of Silicone Breast Implants In The U.S. 1. The intrinsic differences between science and the law mean that there will continue to be tension at the interface between the two. 2. Weak scientific evidence makes for weak scientific, clinical and legal judgments. 3. Health policy can influence the weighing of evidence as did the FDA ban on gel filled silicone breast implants in 1992. 4. As the probative value of scientific evidence decreases (that is, the quality and relevance of the evidence) the courts have increasing difficulty in evaluation. 5. Weak scientific evidence along with poor legal judgments can distort clinical understanding and result in harm to patients. 6. Widely publicized speculation and litigation can obscure less dramatic but frequent and serious complications. 7. Clinicans, toxicologists, industry and regulators should maintain surveillance of medical devices, in representative groups if not in all recipients of the devices. 8. The precise identity and composition of each medical device implanted into a person should be recorded both by the manufacturer and in the health care record. 9. The factual basis for informed consent should be vetted by a disinterested party. 10. Patients, clinicians and industry all have a strong interest in assuring the safety of medical devices through regulation. 11. The criteria and process for evaluating the admissibility of scientific evidence in legal proceedings have been improved but universal adoption of the improvements has not been accomplished and further changes may be necessary. (+info)
Injectable silicone biomaterial for faecal incontinence due to internal anal sphincter dysfunction.
BACKGROUND: A weak or disrupted internal anal sphincter can cause passive faecal incontinence. Conservative measures may help some patients but there is no simple surgical solution for those who fail conservative treatment. A successful technique using trans-sphincteric injection of a bulking agent to augment the internal anal sphincter was developed in a previous pilot study. AIM: To determine the clinical results and underlying physiological effects of biomaterial injection. PATIENTS: Six patients (four males, median age 53 years (range 36-65)) with faecal incontinence to solid or liquid stool related to poor internal anal sphincter function, of varied aetiology, were recruited. METHODS: Silicone based biomaterial injections were performed, under local anaesthesia, with antibiotic cover. Three injections were placed circumferentially, trans-sphincterically, entering away from the anal margin and injecting at or just above the dentate line. Anorectal physiological studies, endoanal ultrasound, a bowel symptom diary, a validated incontinence score, and quality of life questionnaires were completed before treatment and on completion of follow up. RESULTS: At a median follow up of 18 months (range 15-19), five of six patients had marked symptom improvement. Faecal incontinence scores improved from a median of 14/24 (range 11-20) before to 8/24 (6-15) after injection. Short form-36 quality of life physical and social function scores improved from a median of 26/100 (5-33) to 79/100 (25-100) and from 10/100 (5-37) to 100/100 (50-100), respectively. There was a corresponding physiological increase in maximum anal resting and squeeze pressures. Ultrasound showed the Bioplastique to be retained in the correct position in the improved patients without migration. There were no complications. CONCLUSION: Trans-sphincteric injection of silicone biomaterial can provide a marked improvement in faecal incontinence related to a weak or disrupted internal anal sphincter. This is associated with improved sphincter function and quality of life. (+info)
Silicate antibodies in Danish women with silicone breast implants.
OBJECTIVES: To use a new immunological assay to evaluate silicate antibody levels in women with and without silicone breast implants (SBIs). METHODS: Women (n=186) were identified through Danish population-based registers and categorized into six groups defined by prior breast surgery (breast implantation/breast reduction/no breast surgery) and by the presence or absence of prior hospital diagnoses of soft-tissue rheumatism (muscular rheumatism, ICD-8 codes 717.90 and 717.99). The women underwent blood tests, a silicate antibody assay and a clinical examination. Severity of rheumatic symptoms/signs was scored from 1 (none) to 5 (severe). RESULTS: The level of silicate antibodies was not significantly different between the three groups with prior soft-tissue rheumatism (P > 0.5), with the lowest value among women with SBIs. Among women who had no prior diagnosis of soft-tissue rheumatism, silicate antibody levels were highest in women with SBIs (P < 0.01). No significant correlations were observed between silicate antibody levels and symptom severity scores. CONCLUSIONS: Silicate antibodies were not consistently associated with SBIs and were not correlated with rheumatic symptoms. The clinical relevance of these antibodies remains questionable. (+info)
Evaluation of the rupture of silicone breast implants by mammography, ultrasonography and magnetic resonance imaging in asymptomatic patients: correlation with surgical findings.
CONTEXT: Different imaging methods can identify the integrity of breast implants and also the extent of possible silicone leakage. Mammography, ultrasonography and magnetic resonance imaging are often used to evaluate the integrity of breast implants, usually in patients that are symptomatic for rupture. A group of clinically asymptomatic patients was taken as a sample. These patients wanted to remove or change their breast implants for psychological or cosmetic reasons. OBJECTIVE: The purpose of this study was to compare the efficacy of mammography, sonography and magnetic resonance imaging in the detection of breast implant rupture in an asymptomatic population. TYPE OF STUDY: Prospective study. SETTING: Department of Diagnostic Imaging, Universidade de Sao Paulo, Sao Paulo, Brazil. METHODS: The participants were 44 asymptomatic patients who subsequently had implants surgically removed. Eighty-three implants were evaluated by both film-screen mammography and high-resolution sonography and 77 implants were evaluated by magnetic resonance imaging. The sensitivity and specificity of mammography, ultrasonography and magnetic resonance imaging were assessed using predetermined diagnostic criteria for implant rupture. All radiological signs were discussed and false positives and false negatives were retrospectively evaluated to identify the pitfalls in the investigations. RESULTS: The respective sensitivity and specificity of mammography were 20% and 89%; sonography, 30% and 81%; and magnetic resonance imaging, 64% and 77%. The differences between patients with breast implants for cosmetic and oncological reasons were discussed. CONCLUSIONS: Our experience suggests that magnetic resonance imaging seems to be the best imaging method on its own for the evaluation of rupturing among asymptomatic patients. (+info)
Approaches to treatment of HIV facial lipoatrophy.
HIV-associated facial lipoatrophy has become epidemic among the greater than 1 million HIV-infected individuals living in the United States. Those affected usually have well-controlled HIV disease, and are most often healthy and living productive lives. However, their facial appearance often suggests the opposite and frequently serves as a stigma and psychological burden. Treatment approaches may be divided into three categories: 1) Surgically placed alloplastic, autologous, or synthetic implants; 2) Injection of temporary fillers; 3) Injection of permanent fillers, including liquid injectable silicone. Salient aspects of each treatment are reviewed, along with new techniques and pearls on the correct use of liquid injectable silicone. (+info)