Dinoff, Adam

Abstract The long-term benefits conferred by cardiac rehabilitation (CR) in those with coronary artery disease (CAD) are strongly linked with an improvement in cardiopulmonary fitness. This study aimed to determine the association between peripheral sphingolipids and cardiopulmonary fitness in CAD subjects undertaking CR. Patients with CAD (n = 100, mean age = 64 ± 6 years, 85% male, mean years of education = 17 ± 3 years) underwent 6 months of CR with blood collected at baseline, 3 and 6 months. Cardiopulmonary fitness was assessed by measuring peak oxygen uptake (VO2peak) at all time points. High performance liquid chromatography coupled electrospray ionization tandem mass spectrometry was used to quantify plasma sphingolipid concentrations. Cross-sectional and longitudinal associations between sphingolipids and VO2peak were assessed using linear regressions and mixed models, respectively. Higher concentrations of sphingomyelin C18:1 (β = −0.26, p = .01), ceramides C16:0 (β = −0.24, p = .02), C18:0 (β = −0.29, p = .002), C20:0 (β = −0.24, p = .02) and C24:1 (β = −0.24, p = .01) and monohexylceramide C18:0 (β = −0.23, p = .02) were associated with poorer VO2peak at baseline. An improvement in VO2peak was associated with a decrease in sphingomyelin C18:1 (b = −10.09, p = .006), ceramides C16:0 (b = −9.25, p = .0003), C18:0 (b = −5.44, p = .0003) and C24:1 (b = −2.46, p = .006) and monohexylceramide C18:0 (b = −5.37, p = .005). Specific long chain sphingolipids may be useful markers of fitness and response to exercise in CAD.

AbstractBackgroundDepression is highly prevalent in individuals with coronary artery disease (CAD) and increases the risk of future cardiac events and mortality. Sphingolipids have been implicated in the pathophysiology of both CAD and depression. This study assessed the association between plasma sphingolipid concentrations and depressive symptoms in CAD subjects.MethodsDepressive symptoms were measured using the depression subscale of the self‐reported Hospital Anxiety and Depression Scale (HADS). Sphingolipid concentrations were measured from fasting plasma samples using high‐performance liquid chromatography‐coupled electrospray ionization tandem mass spectrometry (LC/MS/MS). Linear regression models were used to assess associations between log‐transformed concentrations of plasma sphingolipids and depressive symptoms.ResultsA total of 111 CAD patients (mean (SD) age = 63.6 ± 6.4, 84.7% male) were included. In linear regression analyses, higher plasma concentrations of ceramides C16:0 (β = 0.204, p = .026) and C18:0 (β = 0.209, p = .023) and sphingomyelin SM18:1 (β = 0.210, p = .024) were significantly associated with higher HADS depression subscale score after adjusting for covariates.ConclusionSphingolipids, in particular the ceramide species C16:0 and C18:0 and the sphingomyelin species SM18:1, may be implicated in the pathophysiology of depression in CAD. The association between plasma sphingolipid concentrations and depression should be further examined in CAD patients and in other populations.