Factors, age and sex related values of dxa assessed spine and hip bone mineral content and Bone mineral density in urban congolese population

Introduction: WHO criteria for the diagnosis of osteoporosis and the associated risks of fractures are based on bone parameters assessed by dual x absorptiometry wich will be compared with normative T-score or Z-score values of the same ethnical origine. Thus the necessity to establish normative data for each population according to habit and ethnicity. Normative Data including male and female and studies about factors of bone mass for Congolese populations were lacking. This study aims to establish these normative values and to determine factors influencing bone mass in Congilese population. Materials and Methods: 660 people: 56 men and 604 women were recruited after public media advertising and undergoes DXA of spine and hip from June 2016 to June 2017. All the subjects undergoes also clinical examination by a physician, DXA, and biological tests from blood and urines samples. To be included in the study, one must agreed and fulfill the conditions of absence of factor affecting bone metabolism. Results: Bone mass parameters shows a growth up to the peak that is reached in the fourth decade followed by a slow decay that causes a loss of nearly 14.2% to 20 % in BMC and BMD. The BMD and BMC values are higher in male and the decay were present in both sex but more pronounced in female. Age, BMI, serum calcium, OH Vitamine D, serum iron, and cholesterol are significative bone mass factors in single regression models but in multiple regression models only Age and Calcium remains significative factors on all sites while BMI and cholesterol are selectively significant for sites and parameters.