Absent circadian variation of blood pressure in patients with anorexia nervosa

Objective: To examine whether circadian rhythm of blood pressure (BP) is al tered in patients with anorexia nervosa (AN), and if so, to determine wheth er it is reversible after refeeding. Study design: Ambulatory BP monitoring was performed on 17 female inpatient s with AN (mean age, 13.3 +/- 1.9 years) at the time of admission and seria lly during refeeding; 17 age-matched normal weight, normotensive female inp atients served as control subjects. Results: Patients with AN had lost an average of 23.4% +/- 11.5% of body we ight before the illness. Weight after refeeding was 105.6% +/- 9.2% of that before illness. Mean 24-hour systolic BP (SBP) (96.5 +/- 8.6 mm Hg) and di astolic BP (DBP) (53.4 +/- 5.8 mm Hg) were significantly lower in patients with AN compared with those of control subjects (SBP, 106.1 +/- 6.5 mm Hg; DBP 60.2 +/- 5.8 mm Hg). Although awake SEP and DBP were also lower in pati ents with AN, asleep SEP and DBP were not statistically different from thos e of control subjects. Night/day BP ratio in the control group was 0.93 +/- 0.06 in systolic and 0.92 +/- 0.09 in diastolic. Those values were signifi cantly elevated in patients with AN (systolic 1.00 +/- 0.09 and diastolic 1 .00 +/- 0.09). After refeeding, the ratio decreased to 0.88 +/- 0.09 and 0. 90 +/- 0.08, respectively (Loth P < .05 vs baseline). Conclusions: In patients with AN, circadian variation of BP is absent. This reverts to normal after refeeding.