The key to coverage is whether the individual requires a skilled provider to ensure the services are safe and effective, not whether improvement is expected. (And the individual meets other Medicare home health qualifying criteria: is homebound and has proper provider certifications.)
“Speech-language pathology would be covered where a skilled service can only be provided by a skilled speech-language pathologist and where it is reasonable expected that the skilled service will improve, maintain, or prevent or slow deterioration in the patient’s ability to carry out communication or feeding activities.” [Emphasis added.]
– Medicare Benefit Policy Manual, Chapter 7, Home Health Services, Section 40.2.3
For more information see CMA’s Home Health Quick Guide and Infographic