One of the reasons West Penn Allegheny Health System fared so badly in the recently concluded fiscal year, according to a spokeswoman's remarks last week, was because of "much higher bad debt." More than $80 million of it, to be precise. At hospitals across the country, overdue patient invoices are increasingly being converted to the bad debt column. A year ago, the Cleveland Clinic reported that its spending on bad debt had increased 49 percent, to $86 million, for the fiscal year. One driver behind the increase, related partly to the economy as well as the ever-increasing cost of health care, is the growing adoption of higher deductible, higher co-pay health plans.