HIPAA-Compliant Patient Data Encryption Middleware

Design a SQLAlchemy-based encryption middleware for patient records that automatically encrypts sensitive fields using AES-256 encryption. Implement transparent encryption/decryption for fields like SSN, medical history, and contact information. Create a robust key management system that supports automatic key rotation every 90 days and provides detailed audit logging of all data access attempts. Ensure the solution is fully compatible with HIPAA compliance requirements and can integrate with existing PostgreSQL healthcare databases.