It has become more common the past year. Know of at least 6 different times a pilot has either died or become incapacitated while flying. Try to find a news article about WS-661 (WestJet 661), Just do a normal search for the incident, I doubt you will find much.
Also, no airline wants to release the data, but the number of pilots out on medical leave are estimated to have increased 300-400% in the past 18 months. You WON'T find that info anywhere online.