GDF15 and Mental deterioration: Of the 107 participants with complete serum biomarker data (Table 3), participants with MCR and slow gait compared with subjective cognitive decline and healthy groups had higher levels of GDF-15 (1132.4 ± 602.5 pg./mL and 1100.47 ± 565.0 pg./mL versus 981.8 ± 506.4 pg./mL and 715.6 ± 315.4 pg./mL, respectively).