New Research Sheds Light on BMD Among US Asian Women

Filipino, Chinese, and Japanese women in the United States have a similar, albeit consistently lower, mean femoral neck‐bone mineral density (BMD) than their White counterparts, according to findings from a new study. 

“BMD reference data exist for US White, Black, and Hispanic (Mexican American) populations but not for US Asians,” the researchers wrote. “Few studies have compared BMD findings among different US Asian ethnicities.”

To evaluate the differences in femoral neck‐BMD by ethnicity and age among US women who are Asian or non‐Hispanic White, the researchers analyzed data on 37,224 Asian women (including 11,147 Filipino; 10,648 Chinese; and 2519 Japanese women) and 115,318 non‐Hispanic White women from a large northern California health care system.

These women were all aged 50 to 79 years and had had BMD testing from 1998 to 2017. Those receiving estrogen or osteoporosis treatment as well as those with recent fracture or select disorders affecting skeletal health had been excluded from the retrospective observational study.

The researchers also assessed for differences in BMD after adjusting for the participants’ height. 

The 3 subgroups of women who were Asian had a similar mean height, which was approximately 6 cm to 8 cm lower than the mean height among the women who were White.

Between the Filipino, Chinese, and Japanese subgroups, there was a less than 3% difference in mean femoral neck‐BMDs. The mean femoral neck‐BMD for each of these subgroups was lower than the mean measurement among women who were White.

The difference in mean femoral neck‐BMD between the Asian and White groups was smaller among younger women (<3%; ages 50 to 59 years) and larger among older women (6%-8%; ages 65-79 years).

According to the researchers, differences in femoral neck‐BMD between women who were White and women who were Asian decreased by approximately 30% to 40% after adjusting for height.

“Mean [femoral neck]‐BMD and height for Filipino, Chinese, and Japanese women were similar but consistently lower than White women, especially among older women. Although Asian‐White BMD differences were substantially attenuated after height adjustment; some differences persisted for older women,” the researchers concluded. “Future studies should investigate potential age‐cohort effects and the extent to which these BMD differences influence fracture risk and clinical care.”

—Colleen Murphy

Reference:

Lo JC, Chandra M, Lee C, Darbinian JA, Ramaswamy M, Ettinger B. Bone mineral density in older U.S. Filipino, Chinese, Japanese, and White women. J Am Geriatr Soc. Published online October 12, 2020. doi:10.1111/jgs.16785