Commentary for Sukkah 51:9

רבא לטעמיה דאמר רבא מצטער פטור מן הסוכה והא אנן תנן חולין ומשמשיהם פטורים מן הסוכה חולה אין מצטער לא אמרי חולה הוא ומשמשיו פטורים מצטער הוא פטור משמשיו לא:

Rava follows his own reasoning, since Rava said: One who is in discomfort is exempt from the Sukkah. But have we not learned: Those who are sick and their attendants [are exempt from the mitzvah of the sukkah] One who is sick but not one who is merely in discomfort? I will explain: A sick person and his attendants are exempt, whereas he who is in discomfort is exempt, but not his attendants.

Rashi on Sukkah