The Feature Of Bone Mineral Density Difference Between Chinese High Altitude And Japanese Sea Level In Inhabitants

PURPOSE: The main purpose of this study was to investigate the effect of high altitude(HA)and sea level(SL)habitation on body composition(BC)and bone mineral density(BMD).METHODS: A total of 800 subjects aged from 20-69 years were included in this study.Three hundreds and sixty one healthy subjects(male =129;female = 232)were from Qinghai-Tibet Plateau(QHTP)2260m above sea level and 439 participants(male = 324;female =115)were from Sendai of Japan(SJ)46m above sea level.Body composition on body mass index,body fat percentage,body fat content,and skeletal muscle mass were measured using InBody S10 and BMD using AOS 100 SA.Questionnaire on age,gender,height,weight,smoking status,alcohol consumption,diet,bone fracture history,bone health,menopause,and exercise duration and load were obtained from subjects.Subjects were divided into 5 groups according to their age(20-29,30-39,40-49,50-59,and 60-69)for the statistical analysis.All data were expressed as mesan ± SD and the differences between HA and SL were analysed by independent T test and Pearson-Correlation.The statistical difference level was defined as ?= 0.05.RESULTS: BMD of the HA residents was significantly higher than that of the SL residents regardless of gender(Males: HA 103.7 ± 10.98 > SL 99.4 ± 11.14,p < 0.01)(Females: HA 108.5 ± 11.06 > SL 104.1±12.43,p < 0.01).There was no significant difference in BMD of young males aged 20-29 in different living altitude.However,in30-39 and 40-49 age groups,male HA residents showed higher BMD than SL folks(30-39: HA 102.5 ± 9.29 > SL 96.7 ± 10.68,p < 0.05)(40-49: HA 104.8 ± 10.35 > SL98.9 ± 11.06,p < 0.05).HA residents,aged from 20-29 and 60-69,had significantly greater BMD compared to SL female residents.(20-29: HA 110.9 ± 13.15 > SL 101.2± 14.12,p < 0.01)(60-69: HA 112.5 ± 12.41 > SL 101.3 ± 11.37,p < 0.01).Body fat percentage(BFP)of the HA residents was significantly higher than that of the SL residents regardless of gender(Males: HA 25.6 ± 6.65% > SL 22.2 ± 7.01%,p <0.01)(Females:HA 32.3 ± 5.86% > SL 28.7 ± 6.77%,p <0.01).There was significant difference in BFP of males aged 30-39 and 50-59 age groups,who lives in HAdemonstrated higher BFP than SL.(30-39: HA26.4 ± 6.80 % >SL 20.9 ± 7.00%,p<0.01)(50-59: HA 27.2 ± 5.81% > SL 24.2 ± 5.76%,p < 0.05).There were significant difference between high-altitude and plain living in BFP of female,age 40-49 and 60-69(40-49: HA34.1±5.34%>SL28.1±5.31%,p<0.01)(40-49: HA 33.6±3.97% >SL24.8±2.34%,p<0.01).CONCLUSIONS: Inhabitants living in high altitude demonstrated higher bone density compared to the residents on sea level in the same age.Thus,living in plateau area might reduce the risk of diseases caused by insufficient bone density.