Investigation Of Bone Mineral Density Of 1071 Cases In Tianjin Area

Objective To study the changes of bone mineral density (BMD ) in people of Tianjin area and provide scientific basis for prevention and management of osteoporosis (OP) , so improve the level of OP prevention. Methods BMD of lumbar vertebrae (L2.4) , Femoral neck, Ward's triangle and trochanters of 1 071 cases aged 20 - 79 was measured by NORLAND XR-36 dual energy X-ray absorptiometry made in USA. They were divided into 12 groups by every five years. All data were saved in the computer and statistical analyses were performed by SPSS 9.0 system for personal computers. Results The BMD peak values of lumbar vertebrae ( 1.2-4) , femoral neck, ward's triangle and trochanters occurred in the age group 35-39 in females. BMD decreased with increasing age over 40, and considerately decreased in age over 50. The BMD peak values that for males seen in 25-29 years old group, BMD decreased with increasing age over 30, and it slower than females. But the evidence decreased in age 60-64. In both sexes, the rate of accumulative loss of BMD at different sites accelerated with increasing age. The rate of accumulative loss of BMD of femoral neck, ward's triangle and trochanters were higher than that of lumbar vertebrae, and the highest rate in ward's triangle. The rate of accumulative loss of BMD seemed higher for females than for males. The rate of loss was increased for females after 50 years old, and that of lumbar vertebrae was 9%-38% in age over 50. Of the three sites of the hip ( femoral neck, ward's triangle and trochanters) ward's triangle had highest rate of loss (30%-50%) in age over 50. The rate of accumulative loss of BMD in males was gradual, but there was also a rapid loss in age group of 60 at femoral neck, ward's triangle and trochanters. 2s below the peak BMD are regarded as the diagnostic criterion of osteoporosis (OP). The detecting rate of osteoporosis (OP) in proximal femur was considerablely higher than that in lumbar vertebrae inmales and females. The morbidity of osteoporosis was less than 10% in both sexes before 49 years old, and after 50 that was increased with age. Statistics according to the most significant parts of the rate of accumulative loss of BMD, the detecting rate showed 30%-50% and 15%- 25% for females and males over 50years old respectively, 60%- 80% and 25%- 40% over 60, 70%- 90% and 45%-55% over 70 years old. Conclusion The investigation and prevention of osteoporosis is more important for females, especially for over 50 years old. As soon as, we should pay attention to males as well. The sensitivity of the detecting of BMD in the upper parts of proximal femur is higher than that in lumbar vertebrae. Patients with normal BMD of lumbar vertebrae, but with significant hyperosteogeny should be diagnosed as osteoporotic based on the BMD of the upper parts of femoral bone.