Forearm bone mineral content（BMC） in relation to age and menopause in Chinese women and Italian women

Two hundred and twenty six Chinese healthy women of han nationality living in Beijing, aged 31—78, and 1115 Italian healthy white women of italian nationality living in Rome, aged 31—85, were examined. They were divided into 11 groups with an interval of 5 years. The postmenopausal women were again segregated into 7 groups of various postmenopausal periods. Those with regularl menstruation were used as controls. A 1100—type bone density scanner by Denmark Nuclear Data Inc. was used in China, while Nordland-Cameron Bone Mineral Analyzer, in Italy. Both systems were single photon absorptiometry using ¹²⁵I as source, equipped with computer for autopsitioning, calculating, recording and storing data.
The results showed that neither Chinese nor Italia women had change in their BMC before 45 years of age. However, decrease in BMC became marked after the age of 51 in Chinese women and after age 46 in Italian women, while at the age of 61—76, the rate of decrease lessened until 81, when BMC again decreased rapidly.
The comparison between BMC decrese in relation to age and to postmenopausal period showed that the latter was more important than chronological age both in Chinese and Italian women.
Furthermore, it seems that Chinese women sufter from postmenopausal osteoprpsis in younger age than Italian women, and, therefore, have higher incidence of osteoporosis.
The different trends of forearm BMC change between Chinese Hart women and Italian women support the importance of racial effect, probably in relation to heredity, geopraphical location, physical activity and diet as well on BMC during menopausal periord.