体重指数与IIS系统在脊髓小脑共济失调3型研究中的作用

The body mass index change and abnormal of IIS system in spinocerebellar ataxia type 3

目的研究脊髓小脑共济失调3型(spinocerebellar ataxia type 3,SCA3)患者体重指数(body mass index,BMI)与胰岛素/胰岛素样生长因子1(IIS)系统、临床和生化指标的相关性。方法比较21例SCA3型患者和性别年龄与之相匹配的22例健康对照者的BMI、血清胰岛素(Ins)、胰岛素样生长因子1(IGF-1)及其结合蛋白3(IGFBP-3)的差异,并分析BMI和Ins、IGF-1、IGFBP-3、CAG重复序列、年龄、发病年龄、病程及国际协作共济失调评估量表(ICARS)总评分及各分项评分间的相关性。结果(1)与健康对照组相比,SCA3型患者BMI以及Ins、IGF-1、IGFBP-3水平降低(均P<0.05),血清IGF-1/IGFBP-3比值在两组间比较差异无统计学意义(P>0.05)。(2)Spearman相关分析显示,BMI与血清Ins水平呈正相关(r=0.504,P=0.020),与CAG重复序列、ICARS总评分及眼球运动评分呈负相关(r=-0.566,P=0.018;r=-0.503,P=0.047;r=-0.617,P=0.011),与其他临床及生化指标无明显相关性(P>0.05);姿势和步态障碍评分与中、重度SCA3患者组BMI值呈负相关(r=-0.824,P=0.006),与轻度SCA3患者组BMI值无明显相关性(r=-0.404,P=0.171)。结论体质量减轻可能是SCA3型患者的早期症状,可协助临床诊断及疾病分期。

Objective To evaluate the body mass index（BMI）of patients with spinocerebellar ataxia type 3（SCA3）and to assess its correlations with insulin/insulin like growth factor 1（IIS）system,clinical and biochemical findings.Methods A case-control study of the differences of serum insulin,insulin like growth factor 1（IGF-1）,and insulin-like growth factor binding protein 3（IGFBP-3）between 21SCA3 patients and 22 healthy subjects matched by sex and age was performed.The correlations between BMI and insulin,IGF-1and IGFBP-3,age,age of onset,disease duration,CAG repeat size,total and clausal scores of the international cooperative ataxia rating scale（ICARS）were analyzed.Results（1）Comparing with the control subjects,BMI,serum levels of insulin,IGF-1,and IGFBP-3 were lower in SCA3 patients（P〈0.05）,whereas IGF-1/IGFBP-3were not statistically different between control and SCA3 subjects（P〉0.05）.（2）By Spearman analysis,BMI presented a negative correlation with CAG repeat size,total scores of ICARS,and scores of eyeball movement（r=-0.566,P=0.018;r=-0.503,P=0.047;r=-0.617,P=0.011）,whereas it has a positive correlation with serum insulin levels（r=0.504,P=0.020）;It has no correlation with other clinical or biochemical index（P〉0.05）.ICARS posture gait score was negatively related with BMI in moderate and severe SCA3patients（r=-0.824,P=0.006）,but not correlated with mild SCA3 patients.Conclusions Weight loss might be a primary disturbance of SCA3,which can help to make diagnosis and assess the severity of the disease.