[Changes in bone mass with age. Transversal study on a female population using photon densitometry].
In order to evaluate the age-related changes of the bone mineral content (BMC), 281 clinically healthy women (20-80 year old) underwent single photon abosorptiometry (SPA) on the distal third of the radius (where there is a prevalence of cortical bone); 161 subjects of this group were examined also by dual photon absorptiometry (DPA) of the lumbar tract of the spine (L2-L4) (trabecular bone). The relationship of trabecular BMC with age is described by a cubic polynomial regression (r = 0.46; p less than 0.0001) that shows an increase in BMC until 31 years of age followed by a decrease with a minimum at the age of 78; afterwards trabecular BMC adds an apparent increase. No increase in the rate of trabecular BMC loss was seen after the menopause. A positive correlation was found between body weight and vertebral BMC. The behaviour of cortical BMC with age is described by a quadratic regression (r = 0.42; p less than 0.0001) that shows an increase until 32 years of age followed by a decrease. Cortical BMC shows a significant decrease after menopause. No correlation was found between body weight and cortical BMC. These findings underline the different behaviour of trabecular and cortical bone tissue with age; in addition, the relation between trabecular (but not cortical) BMC and body weight argues for an important role of biomechanical factors in the local modulation of bone mass.
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001842:Bone and Bones / Q000032:analysis; D005260:Female; D006801:Humans; D008593:Menopause; D008875:Middle Aged; D008903:Minerals / Q000032:analysis; D010024:Osteoporosis / Q000175:diagnosis*; D013053:Spectrophotometry
D008903:Minerals
Variazioni della massa ossea con l'età. Studio trasversale su una popolazione femminile mediante densitometria fotonica.