Utilidad clínica de los marcadores bioquímicos de remodelado óseo en la mujer posmenopáusica reciente: estudio longitudinal a 2 años

Bone turnover markers and bone mineral density in healthy mother-daughter pairs from South India

Bone turnover markers (BTMs) provide important insights into the dynamics of bone remodelling and are subjected to preanalytical and ethnic variations in addition to influence of genetic and environmental factors.

AIM/OBJECTIVES

To derive ethnicity specific reference range for BTMs and to study their correlation with Bone Mineral Density (BMD) in a cohort of healthy postmenopausal women and their premenopausal daughters and to look at the impact of maternal bone mineral status on daughters bone health.

MATERIAL AND METHODS

This community based cross sectional study included 300 subjects (150 mother-daughter pairs). Demographic details were collected. Fasting blood and a second void morning urine samples were obtained for measurement of BTMs (sCTX, sPTNP1, sOC and urine DPD respectively) and bone mineral parameters. BMD was measured by DXA scan.

RESULTS

Osteoporosis was seen in 44·7% of the postmenopausal women. Ethnicity specific reference ranges of BTMs were derived for the study population. Significant inverse correlation was found between all BTMs (except urine DPD) and BMD(P < 0·05). Daughters of mothers with osteoporosis at spine and femoral neck had lower BMD, compared to daughters of mothers without osteoporosis(P = 0·03 & 0·05).

CONCLUSION

Apart from deriving the ethnicity specific reference range for BTMs and finding a significant inverse correlation between BTM and BMD, this study found significantly lower BMD in daughters of mothers with osteoporosis at spine and femoral neck implicating the probable interplay of genetic, epigenetic and similar environmental factors.

Traditional and novel bone remodeling markers in premenopausal and postmenopausal women

CONTEXT

Bone turnover markers (BTMs) may identify changes in bone remodeling within a relatively short time interval before changes in bone mineral density can be detected. New markers such as osteoprotegerin, receptor activator of nuclear factor-κB ligand, and sclerostin have emerged, but there is little information about their potential use in clinical practice.

OBJECTIVES

The aim of this study was to analyze the ability of several BTMs to predict bone loss in pre- and postmenopausal women and to monitor the efficacy of treatment in osteoporotic women.

DESIGN, PATIENTS, AND SETTING

We performed an observational prospective study in pre- and postmenopausal ambulatory women (n = 72 and n = 152, respectively).

INTERVENTION

Postmenopausal women with osteoporosis (n = 18) were treated with risedronate and calcium. Women filled out a questionnaire and underwent bone mineral density measurement using dual-energy x-ray absorptiometry at the time of enrollment and after 1 year of follow-up. BTMs were measured at baseline, at 6 months, and after 1 year.

RESULTS

Increased levels of N-terminal propeptide of type 1 procollagen (P1NP) and β-type I collagen telopeptides (CTXs) were associated with low bone mineral density in the premenopausal (P = .02 and P = .04, respectively) and postmenopausal (P = .03 and P = .02) groups. The best analytical performance to diagnose osteoporosis was for β-CTX, osteocalcin, and P1NP, with areas under the curve of 0.70 (P = .005), 0.64 (P = .048), and 0.71 (P = .003). A significant decrease was found in P1NP, osteocalcin, tartrate-resistant acid phosphatase-5b, β-CTX, and bone alkaline phosphatase after 1 year of treatment (all P < .05).

CONCLUSIONS

Our data suggest that measurement of β-CTX and P1NP shows adequate analytical performance and could potentially be included in algorithms for the screening of osteoporosis. Furthermore, these two markers, along with osteocalcin and tartrate-resistant acid phosphatase-5b, are useful to monitor the response to risedronate.

Functional autonomy, bone mineral density (BMD) and serum osteocalcin levels in older female participants of an aquatic exercise program (AAG)

The aim of the present study was to evaluate the effects of an AAG on BMD, osteocalcin and functional autonomy in older women. The sample consisted of eighty-two post-menopausal women with low BMD, randomly divided into two groups: the Aquatic Aerobics Group [AAG; n=42; age: 66.8±4.2years], submitted to two weekly sessions over eight months, and the Control Group (GC; n=42; age: 66.9±3.2years), which did not participate in regular exercise. BMD was measured by Dual Energy X-ray Absorptiometry [DXA] of the lumbar and femur, and serum osteocalcin was measured using electrochemiluminescence. A functional autonomy assessment protocol (GDLAM, 2004) was also applied. Statistical analyses used were repeated measures ANOVA and Tukey's post hoc tests. The results showed a significant improvement in tests following the GDLAM protocol: 10 meters walk (10mw) -p=0.003; rising from a ventral decubitus position (RVDP) - Δ%=0.78, p<0.001; rising from a chair and moving around the house (RCMH) -p<0.001 and autonomy index (AI) -p=0.007, with more favorable results observed in the AAG when compared to the CG. The AAG achieved the best results for BMD; however, no inter or intragroup statistical differences were recorded for total femur -p=0.975 and lumbar L(2)-L(4)p=0.597. For serum osteocalcin, intra and intergroup statistical differences of p=0.042 and p=0.027 were observed in the AAG, respectively. This demonstrates that an eight-month aquatic aerobic exercise program can improve functional autonomy and osteocalcin levels, although training did not improve lumbar and total femur BMD in the older women.

Biochemical markers in osteoporosis: usefulness in clinical practice

Currently, the measurement of bone remodeling biomarkers is an innovate proposal in clinical evaluation of patients with osteoporosis. Its use may identify patients at increased risk of fracture as well as monitoring therapeutic efficacy. Because they constitute a relatively inexpensive non-invasive measurement, its use should be widespread for serial and frequent measurements of bone turnover. However, their analytical and biological variability limits their clinical applicability.