merous case reports of connective tissue disease in women with gel-, and a few with saline-filled, breast implants, a listing of such anecdotal evidence was not considered profitable. These case reports can be found in the references of this report. Many of them have been reviewed by Sánchez-Guerrero et al. (1994), and some deficiencies of these reports have been listed by Kurland and Homburger (1996), including: poor or absent case definition; failure to apply conventional diagnostic criteria; lack of identification of type of implant; silicone injections of questionable composition; unknown disease status prior to implant; lack of a consistent latent period; and inconsistent effects on symptoms after explantation (Kurland and Homburger, 1996).
The committee found 11 published cohort studies (Edworthy et al., 1998; Friis et al., 1997a; Gabriel et al., 1994; Giltay et al., 1994; Hennekens et al., 1996; Nyrén et al., 1998a; Park et al., 1998; Sánchez-Guerrero et al., 1995a,b; Schusterman et al., 1993; Weisman et al., 1988; and K.E. Wells et al., 1994), five case control studies (Bums et al., 1996; Englert et al., 1996; Hochberg et al., 1996; Strom et al., 1994; and Williams et al., 1997), and one cross-sectional study (Goldman et al., 1995), a total of 17 epidemiological studies of rheumatic diseases. The cohort studies were carried out in different locations in the United States and abroad: Alberta, Canada (Edworthy et al., 1998), Denmark (Friis et al., 1997a), Olmsted County, Minnesota (Gabriel et al., 1994), Amsterdam, Holland (Giltay et al., 1994), national samples in the United States (Hennekens et al., 1996 and Sánchez-Guerrero et al., 1995a,b), Sweden (Nyrén et al., 1998a), southeast Scotland (Park et al., 1998), Texas (Schusterman et al., 1993), San Diego (Weisman et al., 1988), and Florida (Wells et al., 1994). The five case-control studies were performed in Michigan (Burns et al., 1996), Sidney, Australia (Englert et al., 1996), San Diego, Baltimore-Washington, D.C., Pittsburgh (Hochberg et al., 1996), Philadelphia (Strom et al., 1994), and across the United States (Williams et al., 1997). The cross-sectional study was done in Atlanta, Georgia (Goldman et al., 1995). The principal results of these studies, that is, the risk of CTD associated with silicone breast implants, are summarized in Table 8-1.
Goldman et al. (1995) conducted a cross-sectional study using the computerized clinic records of 4,229 women, primarily with RA, seen in a rheumatology practice between 1982 and 1992. He found 721 women with connective tissue disease (12 with implants) and 3,508 control women (138 with implants) (85% of the implants were gel filled, 4% saline filled and 12% unknown). The adjusted odds ratio for all RA and connective tissue disease was 0.52 (95% confidence interval [CI], 0.29-0.92), even