Consumer caution produced lackluster performances by U.S. retailers in August, with many major companies reporting modest single-digit increases in same-store figures, analysts said yesterday.

"We are seeing a slowdown in consumer spending," said Janet Magnano, vice president of research for Jesup, Josephthal & Co. in New York.

"We have been seeing it for well over a year on big ticket-items such as automobiles and houses, and now it's affecting discretionary items. Consumers are exercising great caution; there are fears of a higher cost of living."

The Middle East crisis also was blamed for dampening consumer spending, but the domestic economy was the underlying reason for the retailers' performance, analysts said.

Wal-Mart Stores Inc., based in Bentonville, Ark., outperformed its major competitors Sears, Roebuck & Co. and K mart Corp., reporting revenues of $2.7 billion -- a 30 percent increase over August 1989 -- and a 13 percent increase in same-store sales, the figure that reflects the performance by stores open at the same time last year.

Chicago-based Sears, with revenue of $2.6 billion, reported a 4.7 percent increase in revenue and a 4.1 percent rise in same-store sales.

K mart, based in Troy, Mich., reported an 11.1 percent increase in revenue to $2.3 billion.

"It appears to me the numbers are not exciting," said Hugh Johnson, chief economist for First Albany Corp., in Albany, N.Y. "If you were to adjust them for inflation, some of them would be flat."

He said the figures should normally be bolstered by back-to-school sales increases.

Both Sears and K mart said apparel sales were strong, with K mart citing back-to-school sales that "more than offset some softness in electronics and other big-ticket categories."

Wal-Mart was the "standout performer," Magnano said, benefiting from a strong presence outside major metropolitan areas and good merchandising.

Other apparel retailers, such as The Limited Inc., based in Columbus, Ohio, suffered from a predominance of cold-weather merchandise in the stores at a time when much of the country was experiencing warm weather, Magnano said.

The Limited reported an increase of 14 percent in sales to $408.3 million, with a 1 percent increase in same-store sales.

San Bruno, Calif.-based retailer The Gap, however, posted a strong 14 percent increase in same-store sales and a 24 percent increase in overall revenues to $166 million for the period.

Among other major retailers, Minneapolis-based Dayton Hudson Corp. said sales were up 19.9 percent to $1.19 billion, while the same-store figure rose 8 percent.

J.C. Penney, based in Dallas, reported a 1.2 percent decline in sales, with a total figure of $1.2 billion, and a same-store drop of 2.4 percent. Board Chairman William R. Howell said the comparison was on the basis of an "exceptionally strong" performance in August 1989. He said this year's strong sales categories included women's dresses, men's suits and men's athletic apparel, while furniture sales were off substantially.