. Author manuscript; available in PMC: 2023 Oct 1.

Published in final edited form as: Ocul Surf. 2022 Aug 13;26:100–110. doi: 10.1016/j.jtos.2022.07.006

Table 1.

Comparison of changes in sphingolipid composition by patient population

Patient Population	Source	Cer (%)	SM (%)	S1P (%)
DE Symptoms¹⁰⁹ vs No DE Symptoms	Meibum	Increased	Increased	Not studied
Blepharitis + ATD vs Blepharitis¹¹⁸	Meibum	Not studied	Decreased	Not studied
Blepharitis + ATD vs Controls¹¹⁸	Meibum	Not studied	Decreased	Not studied
MGD: Individuals with poor quality meibum vs good quality meibum²⁶	Meibum	Decreased	Increased	Decreased
MGD: Individuals with poor quality meibum vs good quality meibum¹²⁹	Meibum	Decreased^*	Increased	Not studied
MGD: Individuals with poor quality meibum vs good quality meibum¹²⁹	Tears	Increased^*	Increased^*	Not studied

DE, dry eye; ATD, aqueous tear deficiency; MGD, meibomian gland dysfunction; Cer, ceramide; SM, sphingomyelin; S1P, sphingosine 1-phosphate

Difference was not statistically significant