Comparisons of prevalence and clinical and environmental characteristics between Tibetan and Han Women with polycystic ovarian syndrome in Tibetan Plateau

Objective By the preliminary comparison study on the constituent ratio and clinical characteristics of polycystic ovary syndrome (PCOS) in Tibetan and Han women in Tibetan Plateau, we aimed to find the relevance of its pathogenic factors, and to guide the treatment of PCOS in the plateau region and improve the prognosis. Methods The general situation and clinical data of 165 patients who were diagnosed with PCOS from December 1, 2015 to November 30, 2016 in the Department of Obstetrics and Gynecology of the People′s Hospital of Tibet Autonomous Region were analyzed retrospectively. The prevalence of PCOS among Tibetan and Han women in Tibetan Plateau were compared. Results (1) A total of 1 520 patients were treated in the Tibet Autonomous Region People′s Hospital gynecological endocrinology clinics in one year (Tibetan 865 cases, Han 617 cases, other ethnic groups 38 cases), of which patients with PCOS accounted for 10.9% (165/1520). (2) The incidence of Tibetan PCOS patients with oligomenorrhea, infertility, amenorrhea, acne, hairy, LH/FSH inverted, overweight (BMI≥24), and waist circumference >80 cm were 21.2% (35/165), 20.6% (34/165), 16.4% (27/165), 28.5% (47/165), 17% (28/165), 38.2% (63/165), 23.6% (39/165), and 36.4% (60/165), respectively. The incidence of Han PCOS patients with oligomenorrhea, infertility, amenorrhea, acne, hairy, LH/FSH inverted, overweight (BMI≥24), and waist circumference >80 cm were 7.9% (13/165), 10.3% (17/165), 9.1% (15/165), 15.2% (25/165), 9.7% (16/165), 14.5% (24/165), 10.9% (18/165) and 19.4% (32/165), respectively. The proportion of high testosterone in Tibetan PCOS patients was higher than that in Han PCOS patients with statistically significant. (3) The chief complaint of Tibetan PCOS patients were oligomenorrhea and infertility, and the chief complaint of Han PCOS patients were infertility and amenorrhea. (4) The constituent ratio of outpatient clinics in Nyingchi who were with PCOS at an average elevation of about 3 000 meters in the Tibetan Plateau was 7.9% (13/165), and the average constituent ratio in Lhasa, Xigatse and Nagqu over 3 500 meters above sea level was 35.8% (59/165), 16.9% (28/165) and 15.8% (26/165), respectively. Conclusion The prevalence of PCOS in Tibetan areas is slightly higher than that in the international community. The clinical manifestations of Tibetan patients with PCOS are significantly different from those of Han patients with PCOS. The higher the altitude, the higher the incidence of PCOS. Key words: Tibet; High altitude; Polycystic ovary syndrome; Prevalence