Relationship between vitamin D level and thyroid peroxidase level in Qinghai Province / 中华地方病学杂志

ABSTRACT

Objective To investigate the relationship between vitamin D level and thyroid peroxidase (TPO) level in Qinghai Province.Methods In 2015 and 2016,a stratified cluster sampling method was used to select 1 873 people in 9 regions of Qinghai Province,including 935 males and 938 females,the average age was (52.3 ± 10.9) years old,there were 1 040 Han people and 833 Tibetans.Fasting venous blood samples were collected,and vitamin D and TPO levels were detected by a fully automated chemiluminescence immunoassay system,vitamin D and TPO levels were compared in different gender,ethnic group,and altitude populations.Results The vitamin D level was (16.3 ± 7.5) μg/L,and abnormal rate of vitamin D was 89.2％ (1 670/1 873);the TPO level [median (quartile)] was 23.8 (16.0-35.0) U/ml,and the positive rate of TPO was 26.8％ (502/1 873).The vitamin D levels of males and females were (16.9 ± 7.6) and (15.6 ± 7.6) μg/L,respectively,the difference was statistically significant (t =3.684,P ＜ 0.01);the TPO levels were 23.8 (16.4-31.0) and 23.8 (15.9-37.6) U/ml,respectively,the difference was not statistically significant (Z =-1.084,P ＞ 0.05).The vitamin D levels of the Han people and the Tibetans were (16.2 ± 7.8) and (16.3 ± 7.3) μg/L,respectively,the difference was not statistically significant (t =-0.110,P ＞ 0.05);the TPO levels were 23.5 (15.7-34.8) and 24.0 (16.5-35.1) U/ml,respectively,the difference was not statistically significant (Z =-0.078,P ＞ 0.05).The vitamin D levels of middle-altitude (1 500-3 000 m) and high-altitude (＞ 3 000 m) populations were (16.6 ± 7.7) and (15.8 ± 7.5) μg/L,respectively,and the difference was not statistically significant (t =2.126,P ＞ 0.05);the TPO levels were 23.4 (16.0-33.0) and 24.0 (16.0-36.8) U/ml,respectively,the difference was not statistically significant (Z =-1.296,P ＞ 0.05).There was negative correlations between vitamin D level and TPO level,altitude (r =-0.150,-0.052,P＜ 0.05),and no correlation with ethnic group (r =0.003,P ＞ 0.05).Conclusions The vitamin D level is negatively correlated with TPO level in Qinghai population.The abnormal rate of vitamin D is high,and vitamin D level of males is higher than that of females.