title: Hemoglobin levels in Qinghai-Tibet: different effects of gender for Tibetans vs. Han.
abstract: The Tibetan population, long a resident on the Qinghai-Tibetan Plateau, has lower hemoglobin concentrations than Han Chinese migrants, but it is incompletely known how gender affects the hemoglobin concentrations in the two populations at various altitudes. Measurements of hemoglobin concentration were obtained in 5,887 healthy male and female Tibetan and Han residents aged 5-60 yr, at altitudes of 2,664, 3,813, 4,525, and 5,200 m. Multiple regression equations showed the beta-coefficients for altitude and for age were higher (P < 0.05) in Han men than in Tibetan men and in Han women than in Tibetan women. Analysis indicated a significant three-way interaction between altitude, gender, and ethnicity (chi2 = 3.72, P = 0.05). With increasing altitude, men progressively had more hemoglobin than women in the Han, but not the Tibetan, population. Above 2,664 m, this gender-related difference in hemoglobin concentration increased from childhood to young adulthood more in Han than in Tibetans. We suggest that the Han-Tibetan ethnic difference in the effect of altitude on hemoglobin concentration depends to a large extent on gender.
authors.affiliation: High Altitude Medical Research Institute, Nanchua West Road #344, Xining, Qinghai, 810012, PR China. wutianyiqh@hotmail.com
authors.forename: Tianyi
authors.initials: T
authors.lastname: Wu
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Wang
authors.forename: Chunyin
authors.initials: C
authors.lastname: Wei
authors.forename: Huawei
authors.initials: H
authors.lastname: Cheng
authors.forename: Xiaozhen
authors.initials: X
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.lastname: Ge-Dong
authors.forename: Haining
authors.initials: H
authors.lastname: Zhao
authors.forename: Ping
authors.initials: P
authors.lastname: Young
authors.forename: Guilan
authors.initials: G
authors.lastname: Li
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000531:Altitude; D044466:Asian People / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005843:Geography / Q000379:methods; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017678:Sex Distribution; D013223:Statistics as Topic; D018609:Tibet / Q000453:epidemiology
chemical_list: D006454:Hemoglobins