Introduction This study aimed to investigate factors which influences to the serum adiponectin level among Japanese workers with declining renal function.

Methods This study involved all participants who had undergone measurement of the serum adiponectin level at least one time at annual health examination during the period from 2008 to 2016 among Japanese workers in a railway company. We conducted analyses of participants with declining renal function. For those with serum adiponectin levels measured multiple times during this period, health examination data obtained during the year when the most recent level was measured were used for analysis.

The participants were classified into 4 categories according to eGFR. Categories G3a, G3b, G4, and G5 were 45–59, 30–44, 15–29 and <15 mL/min/1.73 m²; and the serum adiponectin level was obtained for each group.

Next, factors’ affecting the serum adiponectin level was investigated among indices of lifestyle-related diseases and different lifestyles measured at health examination. The serum adiponectin level was used as a dependent variable, while eGFR, indices of lifestyle-related diseases, and different lifestyles were used as independent variables. Multiple regression analysis was performed to identify items significantly influences to the serum adiponectin level.

Results This study included 646 participants, and was 98.3% male. The mean serum adiponectin level was 8.6 μg/mL (1.8–32.5). The levels of the categories divided by eGFRs were 8.1 (G3a), 10.3 (G3b), 13.5 (G4), and 15.6 (G5). Multiple regression analysis identified four items as being significantly associated with the serum adiponectin level (standardised regression coefficient): eGFR (0.334), body mass index (0.241), the presence/absence of regular sleeping habits (0.114), and low-density lipoprotein (0.077).

Conclusions In the participants with declining renal function, the serum adiponectin level was significantly associated with some items. Estimated GFR showed the greatest standardised regression coefficient, indicating that eGFR strongly affects the serum adiponectin level.