We wouldnt measure blood sugars this frequently on a critially ill patient in theatre or ITU. Indeed I would consider it dangerous. Even with the most brittle diabetic, we only do readings every 4 hours or so although we vary the times.
Presumably the CAA arent so daft as to want these readings for the individual's safety so they must be collecting data for research. ie using the pilot as a guinea pig. Do they need informed consent for this? Can they refuse a medical because a pilot refuses to participate in research?
There are continuous measurement devices which would be more, um, humane
Some interesting issues here