Looking on the internet deeply has found these results:

(MetS) is the most popular phrase on the web.

(MS) 11,900,000,000 results on the web	(MetS) 12,090,000,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Avonex is used to treat Multiple Sclerosis (MS). Patients diagnosed with relapsing multiple sclerosis (MS). Member States (MS) can choose the measures which respond in the most optimal way to their needs and problems. LR(MS) low resolution (mass spectrometry) Tysabri is used to treat adults with multiple sclerosis (MS). TYSABRI is used to treat multiple sclerosis (MS). The message content shall be uniquely identified by means of the message reference (in BGM 1004) and the message sender identification (in NAD(MS) 3039). Rebif is used to treat patients with relapsing multiple sclerosis (MS).	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

(MS)

11,900,000,000 results on the web

(MetS)

12,090,000,000 results on the web

More popular!

Avonex is used to treat Multiple Sclerosis (MS).
Patients diagnosed with relapsing multiple sclerosis (MS).
Member States (MS) can choose the measures which respond in the most optimal way to their needs and problems.
LR(MS) low resolution (mass spectrometry)
Tysabri is used to treat adults with multiple sclerosis (MS).
TYSABRI is used to treat multiple sclerosis (MS).
The message content shall be uniquely identified by means of the message reference (in BGM 1004) and the message sender identification (in NAD(MS) 3039).
Rebif is used to treat patients with relapsing multiple sclerosis (MS).

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.