A case-control study of prosthetic implants and selected chronic diseases in Medicare claims data.

PURPOSE: In an exploratory case-control study of a private insurance-claims database, Greenland and Finkle (Ann Epidemiol. 1996;6:530-540) observed associations of certain prosthetic nonbreast implants with certain connective-tissue and neurologic conditions. We wished to test these associations using the same design with new data.

METHODS

We examined these associations in a case-control analysis of Medicare claims data. To control for possible confounding effects of surgery, our analysis examined nonimplant surgeries of severity similar to implant surgeries.

RESULTS

We again found associations of silicone and metal implants with connective-tissue and neurologic conditions, but we also found similar associations of carpal-tunnel surgery with those conditions.

CONCLUSIONS

Possible explanations for these findings include confounding by presurgical conditions. Therefore, we recommend further studies be done in which such conditions can be measured and controlled.