Table 1 Demographic factors, laboratory data at admission, and treatment indicators of admissions with anorexia nervosa (N = 89)
Characteristic | Total patients (N = 89) | Patients with restrictive type (n = 53) | Patients with binge–purge type (n = 36) | p value for comparisons between types (Student’s t test, except as noted) |
|---|---|---|---|---|
Demographics | ||||
Age (years) | 34.2 ± 11.2 | 37.8 ± 11.0 | 28.9 ± 9.4 | < 0.01 |
Sex (female participants) | 95.5% | 92.5% | 100% | 0.14 (Fisher’s exact test) |
Data at admission | ||||
Weight (kg) | 33.3 ± 9.0 | 31.6 ± 6.4 | 35.7 ± 11.5 | 0.03 |
Body mass index | 13.0 ± 3.3 | 12.3 ± 2.2 | 14.1 ± 4.3 | 0.01 |
Albumin (g/dl) | 3.9 ± 0.7 | 3.8 ± 0.7 | 4.0 ± 0.6 | 0.18 |
Blood urea nitrogen/creatinine ratio | 29.8 ± 18.5 | 35.3 ± 20.7 | 21.6 ± 10.5 | < 0.01 |
Serum potassium level (mmol/l) | 3.6 ± 0.9 | 4.0 ± 0.7 | 3.2 ± 0.9 | < 0.01 |
Serum phosphorus level (mg/dl) | 3.9 ± 1.3 | 3.7 ± 1.4 | 4.1 ± 1.0 | 0.18 |
Albumin-corrected magnesium (mg/dl) (56 cases) | 2.1 ± 0.6 | 2.0 ± 0.4 (36 cases) | 2.4 ± 0.8 (20 cases) | 0.02 |
Caloric intake and weight gain | ||||
Total caloric intake during the first 7 days (kcal/day) | 1237 ± 582 | 1221 ± 646 | 1269 ± 428 | 0.75 |
Weight gain during hospitalization (kg) | 2.1 ± 2.6 | 2.4 ± 2.6 | 1.7 ± 2.6 | 0.18 |
Data during refeeding period* | ||||
Nadir serum potassium level (mmol/l) | 3.1 ± 0.7 | 3.3 ± 0.6 | 2.9 ± 0.8 | < 0.01 |
Time interval between admission and nadir hypokalemia (days) | 2.5 ± 3.4 | 3.3 ± 3.4 | 1.3 ± 3.0 | 0.01 |
Potassium administration during the first 7 days (mEq/day) | 24.1 ± 22.7 | 19.2 ± 13.3 | 33.9 ± 34.5 | 0.01 |
Weight gain during the first 7 days (kg) | 1.1 ± 2.0 | 0.8 ± 1.8 | 1.9 ± 2.0 | 0.03 |
Nadir serum phosphorus level (mg/dl) | 2.7 ± 0.8 | 2.5 ± 0.8 | 3.2 ± 0.7 | < 0.01 |