With the prolonging of duration of DM, the TCD-RAA of MCA and OA in youth-middle aged diabetics, TCD-RAA of ICA and VA in old aged diabetics signifivantly increased.

• 随着病程的延长，中青年糖尿病患者MCA、OA，老年糖尿病患者ICA，VA异常率显著增加。