Leonard Nimoy, the man best known to many as Mr. Spock, was reportedly taken to the hospital late last week after complaining of chest pains. While his condition has not been confirmed, the actor took to Twitter to share some of his poetry with fans on Monday.

Nimoy announced last year that he had been diagnosed with COPD, or Chronic Obstructive Pulmonary Disease, a condition generally caused by smoking that makes breathing particularly difficult. Nimoy was reportedly put on oxygen after the diagnosis and shared advice to his fans via Twitter.

“I quit smoking 30 yrs ago. Not soon enough. I have COPD. Grandpa says, quit now!! LLAP,” Nimoy wrote.

The Star Trek actor shared some of his poetry on Monday but didn’t give fans an update on his health, and his reps had no comment.

“A life is like a garden. Perfect moments can be had, but not preserved, except in memory,” he wrote on Twitter.

I will be sharing my poetry. Today's is, "You and I have Learned," which is in my book, These Words Are for You. LLAP pic.twitter.com/CsHAtmtDnz

— Leonard Nimoy (@TheRealNimoy) February 22, 2015

Nimoy recently stepped back into the role of Spock for Star Trek Into Darkness in 2013, playing an older version of the character called Spock Prime.