Influence of age, sex and diet on bone mass and fracture rate

Morbidity figures from general practice: sex differences in traumatology

BACKGROUND

Trauma prevention starts with to find out the extent of the problem and who it affects. Insight into morbidity figures is therefore necessary.

AIM

To explore sex differences in traumatology and secondary medical care utilization in primary care related to age and socio-economic status (SES).

METHODS

Data were obtained from an academic continuous morbidity registration project in the Netherlands in the period from 1996 to 2006, in which 13,000 patients were followed in 10 successive years.

RESULTS

Sex differences showed a male excess from childhood to 45 years and women showing almost double trauma rates in the elderly. Low SES was associated with the greatest incidence of traumas. The largest sex difference in incidence above 65 years appeared in the high SES with more traumas in women compared with men. From this age on, female morbidity in traumatology outnumbered male morbidity regardless of SES. Considering use of referrals, we found that in the age group 15-45 years men made a greater use of secondary medical care. However, the vastest gender influence in medical care utilization was noticed in the age group over 65 years, outnumbered with women.

CONCLUSION

Young men and old women are the most at risk for traumatic health problems: men presenting with traumata of the skull, the tibia and ocular trauma's and women with fractures of the femur, humerus and wrist. For both men and women the greatest incidence is in the low SES. Family physicians can play a pivotal role in prevention to focus on their patients with high risks.

The impact of clothing style on bone mineral density among women in Turkey

To investigate the effect of veiled clothing style on bone mineral density (BMD). The BMD measurements were performed on the femoral neck and the lumbar spines of adult female population with two different types of clothing taking calcium daily in the normal range according to the proper technique utilizing dual energy X-ray absorptiometry (DEXA). In the lumbar spine measurements, the BMD was measured 1.0020 +/- 0.177 gr/cm2 in cases with veiled clothing style while it was measured 1.0793 +/- 0.169 gr/cm2 in cases with unveiled clothing style (P = 0.049, t = 1.98). In the femoral neck measurements, the BMD was measured 0.8428 +/- 0.146 gr/cm2 in cases with veiled clothing style while it was measured 0.8532 +/- 0.177 in cases with unveiled clothing style (P = 0.548, t = 0.457). Although a decrease in BMD values was observed in both regions with veiled clothing style, only the change in the lumbar spine BMD measurements was statistically significant. These findings suggest that the veiled clothing style may have an adverse effect on BMD by interfering with the sun exposure which is believed to have a key role in bone strength.

The effect of bilateral oophorectomy on bone mineral density

The objective of this study is to investigate the effect of bilateral oophorectomy with total abdominal hysterectomy on bone loss, comparing the cases having surgery before and after the menopause. Bone mineral density (BMD) measurements were obtained from the lumbar spine and femoral neck of totally 127 cases. Out of 127, 105 had surgery before menopause and 22 cases were operated on postmenopausally. The results were compared with the USA normal values. The average age of surgical menopause (SM) cases was 48.45 years with a mean duration of menopause of 5.77 years. The average height and weight were 157.67 cm and 68.19 kg, respectively. The average age of cases having surgery after menopause (SAM) was 62.45 years with a mean duration of 5.59 years after the surgery (duration after menopause is 13.23 years). The average height and weight were 157.45 cm and 73.55 kg, respectively. The average of BMD measurements of lumbar spines L2-L4 was 1.04 gr/cm(2) (BMD = 85.65% and T score = -0.96) in the cases with SM. On the contrary, the average of the BMD measurements of lumbar spines L2-L4 was 1.05 gr/cm(2) (BMD = 101.14% and T score = 0.24) in the cases with SAM. The average of the BMD measurements of femoral neck was 0.85 gr/cm(2) (BMD = 91.39% and T score = -0.64) in the cases with SM. On the contrary, the average of the BMD measurements of femoral neck was 0.82 gr/cm(2) (BMD = 96.69% and T score = -0.31) in the cases with SAM. The bilateral oophorectomy as a surgical procedure is not a statistically significant factor for the acceleration of the bone loss. The main points are the age and the duration of menopause of the patient affecting the bone loss if the surgery is performed before menopause.

Distal tibia areal bone mineral density: use in detecting low aBMD of the hip in young women

Dual-energy X-ray absorptiometry (DXA) is a primary clinical tool for identification of adults with low areal bone mineral density (aBMD) and who are at increased risk for future osteoporosis and fragility fractures. Procedures for several aBMD scans of clinical interest might be limited by artifact, inaccessible anatomical regions, and positioning errors. Sites for scanning that overcome these limitations need further investigation for application to large-scale screening and relevance to clinical decisions regarding diagnosis and treatment. In this study, 146 women (mean +/- SE age = 20.1 +/- 0.1 yr, height = 163.3 +/- 0.2 cm, weight = 60.0 +/- 0.2 kg) underwent DXA of the total body (TB) and right and left total proximal femurs (TPF), total forearms (TF), and distal tibiae (DT). Osteopenia was identified in 24 women. Areal BMD was positively related among all measurement sites (r = 0.55-0.81, all p < 0.001). Total body, TF, and DT aBMD each displayed low sensitivity (0.29-0.33) and high specificity (0.95-0.98) to detect osteopenia of the TPF. Addition of TB fat-free mass slightly enhanced the predictive value of DT aBMD. Overall, DT aBMD can discriminate between osteopenic and normal subjects with comparable accuracy to TB or TF aBMD.

Gender specificity in the genetic determinants of peak bone mass

Peak bone mass is a major determinant of osteoporotic fracture risk. Gender differences in peak bone mass acquisition are well recognized in humans and may account for a substantial share of the increased prevalence of fragility fractures in women compared with men. Skeletal development is regulated by both heritable and environmental factors. Experimental animal models provide a means to circumvent complicating environmental factors. In this study we examined the heritability of peak bone mineral density (BMD) in genetically distinct laboratory mouse strains raised under strict environmental control and sought to identify genetic loci that may contribute to gender differences in this skeletal phenotype. Peak whole body BMD of male and female mice from a panel of 18 recombinant inbred (RI) strains derived from a cross between C57BL/6 and DBA/2 progenitors (BXD) was measured by dual-energy X-ray absorptiometry (DXA). A highly significant relationship existed between body weight and BMD in the BXD RI mice (r2 = 0.25; p = 1 x 10(-43)). To allow for comparison between male and female RI strains, whole body BMD values were corrected for the influence of body weight. The distribution of weight-corrected BMD (WC-BMD) values among the strains indicated the presence of strong genetic influences in both genders, with an estimated narrow sense heritability of 45% and 22% in male and female mice, respectively. Comparison of RI strain results by two-way analysis of variance (ANOVA) revealed a significant strain-by-gender interaction (F1,17,479 = 6.13; p < 0.0001). Quantitative trait locus (QTL) analysis of the BXD RI strain series provisionally identified nine chromosomal sites linked to peak bone mass development in males and seven regions in females. In two cases, the provisional chromosomal loci were shared between genders, but in most cases they were distinct (five female-specific QTLs and six male-specific QTLs). QTL analysis of a genetically heterogeneous F2 population derived from the B6 and D2 progenitor strains provided additional support for the gender specificity of two loci. A significant phenotype-genotype correlation was only observed in male F2 mice at microsatellite marker D7Mit114 on chromosome 7, and a correlation at D2Mit94 on chromosome 2 was only observed in female F2 mice. The present data highlight the important role of gender in the genetic basis of peak bone mass in laboratory mice. Because the male phenotype is associated with considerable fracture risk reduction, an elucidation of the nature of that effect could provide the basis for novel diagnostic, preventative, or therapeutic approaches.

Vertebral and metacarpal morphometry as indicators of nutritional improvement

Because of the importance of nutrition in the development of bone mass, we studied the nutritional state, and bone state by means of metacarpal radiogrammetric measurements and vertebral morphometry in a group of 40 premenopausal women born between 1960 and 1970, mean age 29 +/- 5 years, and in another group of 40 postmenopausal women born between 1934 and 1944, mean age 55 +/- 4 years. Both groups were considered normal, the main characteristic distinguishing them being that the women born between 1934 and 1944 grew up in a period of widespread malnutrition in Spain and the women born between 1960 and 1970 grew up in a period of normal nutrition. Protein, carbohydrate and fat intake in these two periods differed significantly (p < 0.0001 in the three cases by Fischer's exact test). The values of the metacarpal measurements, anterior height of the dorsal vertebrae from T-4 to T-12, and posterior height from L-1 to L-4 between the premenopausal and postmenopausal groups of women were significantly different (p < 0.001) (Anova test). These findings show the importance of nutrition in the development of bone mass during childhood.

Comparison of areal and estimated volumetric bone mineral density values between older men and women

We compared areal bone mineral density (BMD) of the total body (TBMD), antero-posterior lumbar spine at L3 (APS), lateral spine at L3 (LS) and femoral neck (FN). In order to understand better the effect of gender-related size differences on BMD, we also compared the estimated volumetric BMD at L3 (VLS) and the femoral neck (VFN). Subjects were asymptomatic women (n = 22) and men (n = 44) with an age range of 58-79 years. BMD at each site was measured by dual-energy X-ray absorptiometry using a Hologic 2000 in array mode. Results of the statistical analyses (ANOVA) showed the men to have significantly greater BMD at all areal sites [APS, LS (p < 0.05); FN (p < 0.01); TBMD (p < 0.001)]. The two estimated volumetric comparisons, however, showed no gender differences. Results demonstrate how measures from areal BMD measures can be misleading when comparing groups of different size. In older men and women planar measures may overestimate gender differences in BMD.