This could be addressed with monitoring. We have more and more alternatives to choose from. Either from external sensors (movement within the house, toilet usage, phone activity, bank account activity; or, alternatively, from devices worn by the people. This would be a great use of the IoT.
There's a boiling water pot in Japan which will send an sms to you when it's used - since making tea / miso soup is so integral to the lives of especially the elderly here. The idea is if you don't get your morning SMS from gradma's pot something might be up.
Human contact is good, but you can't have person there 24x7, a monitor never tires, and you can address false positives by relying on multiple signals/sensors.
It was one of two carbon monoxide monitors, false positives are treated as failure of the second device to detect - which is, of course, the safest way.
