Determination of vitamin D and analysis of risk factors for osteoporosis in patients with chronic pain

Table 7 Univariate analysis of various factors in the normal and reduced bone mineral density groups of the study group

Factor	Reduced BMD (%)	Normal BMD (%)	c2	P value
Age (yr)			37.533	0.000
< 45	4	27
45-64	43	24
≥ 65	27	4
Sex			23.334	0.000
M	19	20
F	55	35
Ethnicity			8.407	0.038
Tibetan	3	10
Han	60	37
Hui	7	7
Others	4	1
BMI			2.302	0.512
< 18.5	3	4
18.5-22.9	38	33
24-27	22	11
≥ 28	11	7
Occupation			0.144	0.704
Farmer	18	15
Non-farmer	56	40
Vitamin D			1.323	0.724
< 10	21	15
10-20	38	32
20-30	13	6
≥ 30	2	2
PTH			7.503	0.023
< 15	1	0
15-65	41	43
> 65	32	12
Ca			21.396	0.000
< 2.2	39	26
2.2-2.7	17	29
> 2.7	18	0
P			1.312	0.519
< 0.85	5	3
0.85-1.51	61	49
> 1.51	8	3
Altitude			2.988	0.224
1500-2500	58	40
2500-3500	15	11
3500-5800	1	4

BMD: Bone mineral density; PTH: Parathyroid hormone; BMI: Body mass index; M: Male; F: Female.