Correlations between blood lipid, serum cystatin C, and homocysteine levels in patients with Parkinson's disease

Abstract

Aim: The aim was too study the correlations between blood lipid, serum cystatin C (Cys C) and homocysteine (Hcy) levels in patients with Parkinson's disease (PD).

Methods: A total of 322 PD patients and 214 healthy subjects were selected as case and control groups, respectively. The risk factors were explored by logistic regression analysis. The case group was subtyped according to main motor symptoms and age of onset. The correlations of significantly different indices with age, duration of disease, and equivalent dose of levodopa were studied by Spearman's correlation analysis. Receiver operating characteristic curves were plotted to analyze diagnostic values.

Results: Compared to the control group, the PD group had lower serum total cholesterol, triglyceride, and apolipoprotein B (Apo B) levels and higher high-density lipoprotein cholesterol (HDL-C), Hcy, and Cys C levels (P < 0.05). Decreased Apo B level and increased HDL-C and Hcy levels were independent risk factors (P < 0.05). The Cys C level of early-onset patients was lower than of late-onset patients (P < 0.05). Hcy (r = 0.198, P < 0.05) and Cys C (r = 0.281, P < 0.05) levels were positively correlated with age. Triglyceride level was negatively correlated with age (r = -0.202, P < 0.05) and disease duration (r = -0.198, P < 0.05). Unified Parkinson's Disease Rating Scale III score was positively correlated with disease duration (r = 0.435, P < 0.05) and equivalent dose of levodopa (r = 0.423, P < 0.05). The areas under the curve for Apo B, HDL-C, and Hcy levels were 0.341, 0.588, and 0.643, respectively (P < 0.05). The combination of Apo B, HDL-C, and Hcy levels showed high diagnostic value, with a sensitivity of 76.4% and specificity of 69.5%.

Conclusions: Low serum levels of total cholesterol, triglyceride, and Apo B, and high levels of HDL-C, Hcy, and Cys C may be correlated with PD onset and progression. Decreased Apo B level and elevated HDL-C and Hcy levels are independent risk factors. Early-onset and late-onset PD may have different progression mechanisms.

Keywords: Parkinson's disease.; blood lipid; cystatin C; homocysteine.