Selective Determinants of Low Bone Mineral Mass in Adult Women with Anorexia Nervosa

Table 1

Patients’ characteristics: demographic, anthropometric, dietary, and bone data^#.

Demographic and dietary data	Patients	Controls	𝑃-value
Number	66	66
Age (yrs)	20.0 (16–33)	21 (16–22)	ns
Restricting type (%)	68%
Age at menarche (yrs)	13.0 (11–16)	13 (11–15)	ns
Age of onset of anorexia (yrs)	16.0 (13–27)
Duration of illness (yrs)	3.0 (0.7–12)
History of low traumatic fractures, % (𝑛)	12% (8)
Time since last menstrual period (mo)°	9.0 (3–33)
Total duration of amenorrhea (mo)	12.0 (2–84)
Estrogen use, % (𝑛)*	39% (26)
Estrogen use (mo)	38.8±40.3
Current estrogen use	30% (20)
Weight (kg)	42.1±6.9	58.9±8.1	<0.007
Weight (kg) before the onset of illness**	54.7±7.5
Height (cm)	165.0±7.1	164.3±6.0	ns
Body Mass Index (kg/m^2)	15.4±2.1	21.8±3.0	<0.007
% of ideal body weight	71.1±10.0
Calcium intake (mg/d)	835 (281–2000)	835 (510–1074)	ns
Protein intake (g/d)	45 (12–132)	42 (25–57)	ns
Protein intake (g/kg of body weight)	1.11 (0.29–2.92)	0.7 (0.4–1.1)	ns
Physical activity (h/week)	5.6±4.0
Anteroposterior spine BMD (g/cm^2)	0.887±0.12	1.030±0.12	<0.0001
Femoral neck BMD (g/cm^2)	0.753±0.11	0.862±0.11	<0.0001
Total hip BMD (g/cm^2)	0.788±0.11	0.873±0.15	<0.0009

#For skew data, median and interquartile (IQR) range are reported. Otherwise, mean ± SD.
°For amenorrheic women at time of examination.
*At any time since the onset of anorexia.
**Applicable if the onset of the disease occurred after the time of menarche.