Decrease in toe pinch force in male type 2 diabetic patients with diabetic nephropathy

Background The purpose of this cross-sectional study was to investigate the toe pinch force (TPF) of type 2 diabetic patients with diabetic nephropathy by disease stage, and to clarify the factors affecting the TPF. Methods Seventy-four men with diabetic nephropathy (age: 62.7 ± 8.9 years, duration of diabetes: 14.2 ± 8.6 years) were enrolled. According to the staging of diabetic nephropathy, TPF and knee extension force (KEF) were compared among three groups: normoalbuminuria, microalbuminuria, and overt nephropathy. In addition, we investigated factors influencing TPF and KEF by performing multiple regression analysis. Results Normoalbuminuria group, microalbuminuria group, and overt nephropathy group included 26, 25, and 23 patients, respectively. The TPF of the overt nephropathy group (3.15 ± 0.75 kg) was significantly lower than that of the normoalbuminuria (4.2 ± 0.7 kg, p < 0.001) and microalbuminuria groups (3.65 ± 0.81 kg, p = 0.022). The KEF of the overt nephropathy group (37.1 ± 8.3 kgf) was significantly lower than that of the normoalbuminuria group (44.8 ± 8.3 kgf, p = 0.010). Multiple regression analysis revealed that diabetic polyneuropathy (DPN) and diabetic nephropathy were determinant factors of the TPF; and age, body mass index, and diabetic nephropathy were determinant factors of the KEF. Conclusion We found in male patients with diabetic nephropathy, the TPF and KEF decreased with progression of diabetic nephropathy. Furthermore, our findings suggest diabetic nephropathy and DPN are critically involved in the reduction of TPF and KEF.