BONE-DENSITY OF THE CALCANEUS AND FRACTURES IN 75-YEAR-OLD AND 80-YEAR-OLD MEN AND WOMEN

Bone mineral density of the calcaneus in relation to fractures was studied both retrospectively and prospectively among the 75- and 80-year-old men and women resident in the city of Jyvaskyla, Finland, in 1989 and 1990, respectively. The bone measurements were performed at the calcaneus by I-125-photon absorption. Retrospective fracture (RF) history after age 50 was collected by questionnaire and interview, and reported fractures were checked from medical records. In the retrospective study, in the 75-year-olds a fracture was found in 22% (n=22) of men and in 45% (n=84) of women. The corresponding figures for the 80-year-olds were 16% (n=9) and 35% (n=48). Over half of the fractures were of the wrist/hand or ankle/leg. Prospective fractures (PF) were recorded over periods of 29-34 months. Twenty of the 75-year-olds and 16 of the 80-year-olds sustained a fracture during the follow-up period. In the 75-year-olds, the results showed that both RF and PF women, together with the RF men, had lower bone area density (BMD(a)) and volume density (BMD(v)) than the non-fracture (NF) subjects (p=0.001.0.011). In the 80-year-olds, significantly lower BMD(a) was found in the RF women (p=0.008) and lower BMD(a) in the PF women (p=0.024) compared with the NF subjects. During the follow-up period there were no fractures in either of the sex or age groups among those with BMD(a) and BMD(v) values greater than 1 SD above the mean. When using logistic regression analysis, BMD(v) alone explained about 60% of overall fracture probability among the women studied.