Assessment of the skeletal health of healthy Nigerian men and women using quantitative ultrasound

The dietary intake of calcium by African populations, particularly in sub-Saharan Africa, is relatively low compared to the recommended intake for US adults. However, the rate of osteoporotic fractures in West African women is reported to be less than that for Caucasian populations. Because there is little published data regarding the skeletal status of African men and women, we used quantitative ultrasound (QUS) to assess the bone density of 435 Nigerian women and 321 Nigerian men between 16 and 89 years of age. A progressive decline in bone quality was observed beginning at about 40 years of age for both men and women. The mean stiffness index (SI) for the women between 20 and 35 years of age (n = 186) in this study was 102 ± 17. The equation that best described the age versus SI relationship for women was SI = 79.7 + 1.887 (age) + −0.043 (age)2 + 0.00020 (age)3. For Nigerian men, the peak SI of 115 ± 17 was seen in the 20- to 29-year-old age group. For men, the SI values remained above 100 until about age 60 years when a significant decline in SI was then observed. The best-fit curve of SI versus age for men was SI = 134.9 − 1.27 (age) + 0.019 (age)2 − 0.00014 (age)3. The broadband ultrasound attenuation (BUA), speed of sound (SOS), and SI values for the Nigerian men and women were comparable to or higher than those reported for Caucasian and Asian populations. These data should serve as reference values for adult men and women in sub-Saharan Africa.