NY -- Standard&Poor's CreditWire 10/28/98 –- Standard&Poor's today assigned its single-'A' rating to $597.48 million in health facility revenue bonds issued for Catholic Healthcare West, Calif. (see list below). This represents a downgrade from Standard&Poor's previous single-'A'-plus rating on Catholic Healthcare West. The downgrade reflects: -- Declining financial performance, most severely affected by increased costs in Catholic Healthcare West's Shared Business Services project and negative impact from capitated contracts and physician investments; -- Instability in key markets due to capitation and competitive factors, leading to significant fluctuation in financial performance; and -- Risks associated with Catholic Healthcare West's continued aggressive expansion, including the acquisition of eight UniHealth hospitals in southern California. Catholic Healthcare West's