Manager Notification emails - can 1 be sent listing all notifications for each employee?

Summary

Currently the notifications going to Managers are individual emails for each employee. Is there a way to set this up so it is 1 email per performance task?

Content

We are trying to reduce the number of emails going to managers and it is necessary for email notification to go to managers when a performance document due date is approaching.  However this results in many individual emails to the manager.  Is there a way to set this up so that for each performance document 1 email is sent to the manager listing all of the employees for whom a due date is approaching?