Prevalence and Possible Risk Factors of Low Bone Mineral Density in Untreated Female Patients with Systemic Lupus Erythematosus

Table 1

Demographic, clinical data and bone metabolic variables in the SLE patients.

Variable	All SLE patients; ( = 119)
Demographic variables
Age, mean ± SD years	32.6 ± 11.9
Body mass index, mean ± SD kg/m^2	20.6 ± 3.3
Postmenopausal, %	11.9
Menopausal age, mean ± SD years	48.2 ± 1.9
Clinical variables
Disease duration, mean ± SD months	22.1 ± 34.5
Serum creatinine, mean ± SD μmol/liter	53.9 ± 23.3
Serum albumin, mean ± SD g/liter	31.7 ± 6.9
24-hour urine protein, mean ± SD g/24 hr	0.58 ± 0.84
Serum total cholesterol, mean ± SD mmol/liter	3.7 ± 1.4
Serum triglyceride, mean ± SD mmol/liter	2.0 ± 1.3
Serum low density lipoprotein cholesterol, mean ± SD mmol/liter	2.1 ± 0.9
Erythrocyte sedimentation rate, mean ± SD mm/hour	53.8 ± 34.7
C-reactive protein, mean ± SD mg/liter	11.1 ± 13.4
Complement 3, mean ± SD g/liter	0.57 ± 0.31
Complement 4, mean ± SD g/liter	0.10 ± 0.09
Anti-dsDNA antibodies, mean ± SD, IU/milliliter	43.7 ± 37.9
SLEDAI, mean ± SD	11.4 ± 5.4
Bone metabolism variables
25-Hydroxyvitamin D, mean ± SD ng/milliliter	11.9 ± 7.3
Serum calcium, mean ± SD mmol/liter	2.0 ± 0.2
Serum phosphate, mean ± SD mmol/liter	1.1 ± 0.3
Parathyroid hormone (PTH), mean ± SD pg/milliliter	36.2 ± 22.9
Osteocalcin (OC), mean ± SD ng/milliliter	10.3 ± 6.7
C-terminal cross-linking telopeptide of type I collagen (CTX),; mean ± SD pg/milliliter	557.3 ± 396.2

SLE = systemic lupus erythematosus; SLEDAI = Systemic Lupus Erythematosus Disease Activity Index (range 0–105).