Correlation of SM18:1/23:0 (A, B), SM18:1/23:1 (B, C), and SM18:1/26:1 with the
residual amount of sleeping metabolic rate (SMR) after adjustment for age, sex,
fat mass (FM), fat-free mass (FFM), and weight change (%Δwt/yr).
Sex and age were used as covariates for %Δwt/yr. Even after
excluding the study volunteer who lost approximately 6% body weight per
year, SM18:1/23:0 and SM18:1/26:1 tended to correlate with the relative amount
of annual weight change (%Δwt/yr, r = 0.53,
P = 0.08; r = 0.53, P
= 0.08, respectively). SM18:1/23:1 correlated with
%Δwt/yr (r = 0.64, P = 0.02).
Of note, %Δwt/yr for correlation analyses with sphingolipids was
used under the assumption that a linear relationship of initial weight (kg) and
weight change per year (kg/yr) exists. Exploration of this did not support this
assumption in the present study cohort (r = −0.34,
P = 0.20). Thus, weight change per year (kg/yr) was
correlated with sphingolipid moieties. Except for SM18:1/23:0 (r = 0.37,
P = 0.21), all previous associations remained
significant: SM18:1/23:1, and SM18:1/26:1 correlated with kg weight change per
year (r = 0.56, P = 0.05; r = 0.66,
P = 0.01, respectively). Therefore, results for
associations with %Δwt/yr are reported. Pearson’s
correlation and P-value are reported. Abbreviation: SM,
sphingomyelin.