At baseline , patients with CFS had a lower number of steps per day ( P < @ ) , digit span backward score ( P = @ ) , and urinary cortisol to creatinine ratio ( P = @ ) , and a higher fatigue score ( P < @ ) , heart rate responsiveness ( P = @ ) , plasma norepinephrine level ( P < @ ) , and serum C-reactive protein concentration ( P = @ ) compared with healthy controls .