No refresh_token in response when use Client Credentials

ref from: https://msdn.microsoft.com/en-us/library/azure/dn645543.aspx
when get token by grant_type=client_credentials, there is no refresh_token in response,
I also test grant_type=authorization_code, found refresh_token in response.

Is that means refresh_token mechanism is no supported when use Client Credentials?
If not, then how can I do refresn_token ?