CCN2 and type 2 diabetes mellitus: One study did measure plasma CTGF levels in 40 subjects with type 2 diabetes in whom cardiac function was also assessed [41], and reported no difference in CTGF levels between those with normal and abnormal diastolic function and no correlation with echocardiographic measures of diastolic function (E/A and E/e ́ ratio) and plasma CTGF levels [41].