Serum 25(OH)D Level and Parathyroid Hormone in Chinese Adult Population: A Cross-Sectional Study in Guiyang Urban Community from Southeast of China

Table 1

Baseline characteristics (𝑛=1510).

Parameter	Total sample 𝑛 (%)/𝑥±𝑠	Men 𝑛 (%)/𝑥±𝑠	Women 𝑛 (%)/𝑥±𝑠
Age (yr)
20–	267 (17.7)	115 (18.1)	152 (17.4)
30–	351 (23.2)	148 (23.3)	203 (23.2)
40–	329 (21.8)	135 (21.3)	194 (22.1)
50–	284 (18.8)	118 (18.6)	166 (18.9)
60–	155 (10.3)	60 (9.5)	95 (10.8)
70–	124 (8.2)	58 (9.1)	66 (7.5)
20–79	1510 (100)	634 (42.0)	876 (58.0)
Alcohol (%)	444 (29.4)	376 (59.3)	68 (7.8)^a
Smoker (%)	250 (16.6)	206 (32.5)	44 (5.0)^a
Drinking milk	297 (19.7)	118 (18.6)	179 (20.4)
Calcium supplementation	179 (11.9)	51 (8.0)	128 (14.6)
Vitamin D supplementation	48 (3.2)	15 (2.4)	33 (3.8)
Outdoors activity
≤30 min/day	842 (55.8)	377 (59.5)	465 (53.1)
30–60 min/day	351 (23.2)	146 (23.0)	205 (23.4)
≥60 min/day	314 (20.8)	109 (17.2)	205 (23.4)
Education (yr)
0–6	205 (13.6)	51 (8.0)	154 (17.6)
7–9	408 (27.0)	144 (22.7)	264 (30.1)
10–12	353 (23.4)	142 (22.4)	211 (24.1)
≥13	544 (36.0)	297 (46.8)	247 (28.2)
BMI (Kg/m^2)	23.7 ± 3.6	24.1 ± 3.3	23.4 ± 3.7^a
Waist circumference (cm)	81.6 ± 9.8	85.4 ± 8.9	78.7 ± 9.4^a
Waist/hip ratio	0.86 ± 0.06	0.89 ± 0.06	0.83 ± 0.06^a
Total calcium (mmol/L)	2.4 ± 0.2	2.4 ± 0.2	2.4 ± 0.2
Phosphate (mmol/L)	1.1 ± 0.2	1.0 ± 0.2	1.1 ± 0.1^a
Creatinine (umol/L)	63.7 ± 14.7	74.6 ± 12.7	55.8 ± 10.2^a
25(OH)D (ng/mL)	20.4 ± 9.0	20.8 ± 9.7	20.1 ± 8.5
iPTH (pg/mL)	32.1 ± 13.7	33.5 ± 12.4	30.5 ± 13.6^a

Values are presented as mean ± SD. For conversion of 25(OH)D from nmol/liter to ng/mL, divide by 2.496; for conversion of PTH from pmol/liter to pg/mL, multiply by 11.1. Distribution of PTH and of a number of chronic diseases was skewed. Median (interquartile range) is presented; serum 25(OH)D was assessed in a sample (𝑛=1494) and iPTH (𝑛=1414). ^a𝑃<0.01 as compared to men.