“What are the treatment approaches for treating older adults with depression?”

Several options can be discussed with your grandfather's family physician. The choice will depend on several factors, such as chronic medical conditions and current medications.

The best treatments for depression for older adults is to use natural things Isolation is one of the biggest causes. - Help him socialiaze vitamin D is very helpful - especially if he can get outside for awhile each day ( check with his doctor about his blood levels ) be careful to not over do the sugar increase B complex vitamins. These are some easy to do natural things that are very helpful for our older adults

See this link...
https://www.webmd.com/depression/guide/depressionelderly#:~:text=Psychotherapy%20in%20older%20adults%20can%20address%20a%20broad,in%20the%20treatment%20of%20depression%20in%20older%20adults.