Book assigned as a 1980's middle school teacher

I am a librarian and am hitting a brick wall trying to find this book. A patron came to the reference desk looking for a book fitting this description that she read back in the 80s when she was a teacher at a middle school. 

• Young adult novel

• A big theme revolving around government required/sanctioned suicide for the older population 

• The setting was futuristic

• Narrated by a young person whose parents/grandparents were almost of age for the required suicide

• Published before 1990

Thank you!