Breach of Confidentiality At Work UK?

At the end of the month, my line manager sends a spreadsheet to each departmental employee which details everybody's worked hours, prior to sending the information to payroll . This month I had a couple of days off as a result of an upset stomach and not only was the fact that I was off sick detailed on the spreadsheet but also the reason why. Reasons for other members of staffs absence were also been detailed on the spreadsheet. Whilst I'm not really THAT worried that my colleagues know that I had a dickie stomach, I'm still pretty appalled that this information was freely provided to other members of staff. I do not work for a small company, in fact I work for probably the largest employer in the UK and therefore this spreadsheet gets sent to fair number of people in the department and I'm pretty incredulous that something like this could happen. I am very concerned that this spreadsheet breaches both my employee and my colleagues rights to confidentiality. I would like your thoughts.