CHATTANOOGA, Tenn.—Cancer was the leading cause of long-term workplace absence in the United States during 2005, according to UnumProvident Corp.

The Chattanooga, Tenn.-based disability insurer said Monday in a statement that 12% of the long-term disability claims filed with the insurer during the year stemmed from cancer. UnumProvident has reported similar findings annually since it began releasing such claims volume data five years ago, a spokeswoman added.

Pregnancy complications accounted for 10% of long-term disability claims, as do those that stemmed from joint, muscle or connective tissue disease. Back injuries and cardiovascular disease accounted for 8%.

Meanwhile, normal pregnancy accounted for 18% of short-term disability claims filed in 2005, while injuries, excluding back problems, accounted for 10%. Digestive and pregnancy complications accounted for 8% of short-term disability claims.