Correlation Study On Elevated Blood Lipid Level And The Risk Of Relapse In Patients With Neuromyelitis Optica Spectrum Disorders

Objective Neuromyelitis optica spectrum disorders(NMOSD)is an idiopathic inflammatory demyelinating disease of the central nervous system,which mainly invades the optic nerve,spinal cord and brain.In this paper,we summarized the clinical data of the patients with NMOSD and carried out a cross-sectional study.The blood lipids levels of NMOSD patients were analyzed and compared between primary and relapse patients,and the correlation between blood lipids levels and disease recurrence was investigated.A multivariate analysis was used to further investigate the association between low-density lipoprotein cholesterol(LDL-C)level and the risk of disease recurrence and explore the potential inflammatory effects of cholesterol and its clinical significance.Methods The first part:Retrospectively collected clinical and biochemical data of 96NMOSD patients diagnosed in Changhai Hospital and Renji Hospital between January2010 and June 2016 were.According to disease relapses,NMOSD patients were divided into primary and relapse groups,their clinical characteristics and blood biochemical and cerebrospinal fluid test data were compared between the two groups.Patients were grouped according to CHO and LDL-C levels and the rate of recurrence of the disease was compared,the correlation between cholesterol levels and disease recurrence was analyzed by partial correlation adjusted for sex.The second part:Retrospectively collected clinical and biochemical data of 127NMOSD patients diagnosed in Changhai Hospital and Renji Hospital between June 2009and June 2016.The association between serum LDL-C level and relapse was assessed by Spearmen's correlation analysis and multiple linear logistic regression analysis.Receiver operating characteristic(ROC)curve analysis was used to identify optimal cut-off value of LDL-C to distinguish relapse from primary groups,further to determine a target value of lipid lowering in patients with NMOSD.Results The first part:Between the primary group and relapse group,there were statistically significant differences in gender(48.8%vs.80%,p<0.05),cholesterol(CHO)(4.27±0.85 vs.5.18±1.26)and LDL-C level(4.27±0.85 vs.5.18±1.26)(p<0.001),and there were no significant difference in age,upper respiratory infection,gastrointestinal infection,rate of higher cerebrospinal fluid protein,triglyceride(TG)and high density lipoprotein cholesterol(HDL-C)(p>0.05).The percentage of recurrent patients in CHO normal and higher groups were 43.55%and 82.35%respectively,and there was statistically significant difference between the two groups(x~2=13.51,p<0.01);The rate of relapse of LDL-C normal and higher groups were 47.69%and 75%respectively,and there was statistically significant difference between the two groups(x~2=7.58,p<0.01).After adjusting for sex,CHO level was positively correlated with disease relapse(r=0.346,p<0.01),and LDL-C level also was positively correlated with disease relapse(r=0.380,p<0.01).The second part:The LDL-C level was significantly higher in relapse group than that in primary group in whole patients(3.05±0.88 vs.2.34±0.79,p<0.001).According to the normal LDL-C level,the patients were divided into normal LDL-C group and high LDL-C group.The relapse rate of the high LDL-C group was significantly higher than that of the LDL-C normal group(78.00%vs.38.96%,P<0.001).The patients were further divided into T1 group,T2 group,and T3 group according to the level of LDL-C from low to high.The recurrence rates were 10.24%,18.90%,and 25.20%,respectively,the difference between the three groups was statistically significant(P<0.001).When multivariate analysis was performed after adjusting for sex,age,gastrointestinal infection,vision impaired,HDL-C,TG,ALT,BUN,SCR,AQP4-IgG,and IVIG,the odds ratio(OR)(95%CI)of LDL-C level to relapse rate was 2.33(1.35,4.04)(P=0.002);after adjusting the confounding factors,the odds ratio(OR)(95%CI)of T1 group,T2 group,T3 group to relapse rate were 1.0(reference),2.69(1,7.21)(P=0.049)and 4.03(1.36,11.93)(P=0.011),respectively.When hierarchical analysis was performed,according to sex,age,EDSS score,vision impaired,and AQP4-IgG,the statistical results show that after eliminating the interaction of the above factors,the odds ratios of LDL-C level and disease relapse rate can still be observed to be greater than 1(p<0.05),further demonstrating that high blood LDL-C is an independent risk factor of NMOSD disease relapse.Through the ROC curve analysis to determine the lipid-lowering target value,the overall patient's LDL-C should be controlled within 2.795mmol/L,the female LDL-C is controlled within 2.790mmol/L,and the male is controlled within 2.360mmol/L.The AUC values for the area under the ROC curve are all greater than 0.7,suggesting that the determined lipid-lowering target values are moderately accurate for identifying disease relapse.Conclusion This study showed that CHO and LDL-C levels were higher in relapsed NMOSD patients than in primary patients,high CHO and LDL-C level may be associated with disease relapse,and women patients are prone to relapse.After adjusting for confounding risk factors and performing hierarchical analysis,the results demonstrated that higher LDL-C level is an independent risk factor for disease relapse,which has some clinical guiding significance for controlling CHO level in NMOSD patients.