According to an Associated Press investigation, the number of the world’s debt-laden 'zombie' companies has risen, and they will have to pay off $1.1 trillion in loans by year-end.

The number of publicly traded "zombie" companies—those with debt so high they can't even afford the interest on their loans—has increased to about 7,000 worldwide, with 2,000 of them in the US, according to an Associated Press investigation.

And many of them may soon have to face their reckoning, as hundred...