Dn. Patel et al., THE EFFECT OF ETHNICITY ON APPENDICULAR BONE MASS IN WHITE, COLORED AND INDIAN SCHOOLCHILDREN, South African medical journal, 83(11), 1993, pp. 847-853
Ethnic differences in the incidence and prevalence of osteoporosis hav
e been shown throughout the world. In South Africa the prevalence of o
steoporosis is much higher in whites than in blacks. This is surprisin
g, since factors that might predispose to reduce bone mass are more pr
eponderant in black communities. The present research was undertaken t
o determine whether differences in bone mass during the period of bone
accretion could explain the difference in the incidence of osteoporos
is. In this paper we report on differences in appendicular bone mass b
etween white, coloured and Indian children and teenagers (6 - 18 years
) from Johannesburg. The effects of weight, height, puberty and skinfo
ld thickness on bone mass were also assessed. The bone width (BW) of w
hite boys was greater than that of Indian boys, while the bone mineral
content (BMC) and BMC/BW were greater in white boys than in both Indi
an and coloured boys. After adjustment for differences in weight and h
eight, the BW of coloured boys was significantly greater than that of
white boys, while all differences in BMC and BMC/BW became non-signifi
cant. For girls there were no significant differences in bone mass mea
surements, but after adjustment for height and weight coloured girls h
ad significantly greater BMC and BMC/BW than either white or Indian gi
rls. This greater weight- and height-adjusted bone mass in coloured gi
rls is consistent with the impression of a lower incidence of osteopor
osis in coloured women than in white women.