The use of multiple sites for the diagnosis of osteoporosis
- 345 Downloads
It has been suggested that bone mineral density (BMD) measurements should be made at multiple sites, and that the lowest T–score should be taken for the purpose of diagnosing osteoporosis.
The aim of this study was to examine the use of BMD measurements at the femoral neck and lumbar spine alone and in combination for fracture prediction.
We studied 19,071 individuals (68% women) from six prospective population-based cohorts in whom BMD was measured at both sites and fracture outcomes documented over 73,499 patient years. BMD values were converted to Z-scores, and the gradient of risk for any osteoporotic fracture and for hip fracture was examined by using a Poisson model in each cohort and each gender separately. Results of the different studies were merged using weighted β-coefficients.
The gradients of risk for osteoporotic fracture and for hip fracture were similar in men and women. In men and women combined, the risk of any osteoporotic fracture increased by 1.51 [95% confidence interval (CI)=1.42–1.61] per standard deviation (SD) decrease in femoral-neck BMD. For measurements made at the lumbar spine, the gradient of risk was 1.47 (95% CI=1.38–1.56). Where the minimum of the two values was used, the gradient of risk was similar (1.55; 95% CI=1.45–1.64). Higher gradients of risk were observed for hip fracture outcomes: with BMD at the femoral neck, the gradient of risk was 2.45 (95% CI=2.10–2.87), with lumbar BMD was 1.57 (95% CI=1.36–1.82), and with the minimum value of either femoral neck and lumbar spine was 2.11 (95% CI=1.81–2.45). Thus, selecting the lowest value for BMD at either the femoral neck or lumbar spine did not increase the predictive ability of BMD tests. By contrast, the sensitivity increased so that more individuals were identified but at the expense of specificity. Thus, the same effect could be achieved by using a less stringent T–score for the diagnosis of osteoporosis.
Since taking the minimum value of the two measurements does not improve predictive ability, its clinical utility for the diagnosis of osteoporosis is low.
KeywordsBMD Bone strength Collagen Fracture prediction
We are grateful to the Alliance for Better Bone Health, Hologic, IGEA, Lilly, Lunar, Novartis, Pfizer, Roche, Servier, Wyeth, the EU (FP3/5; QLK6–CT–2002–00491) for supporting this study and the International Osteoporosis Foundation, the International Society for Clinical Densitometry and the National Osteoporosis Foundation for their unrestricted support of this work.
- 2.World Health Organisation (1994) Assessment of fracture risk and its application to screening for postmenopausal osteoporosis. Technical Report Series, vol 843. WHO, GeneveGoogle Scholar
- 6.Marshall D, Johnell O, Wedel H (1996) Meta-analysis of how well measures of bone mineral density predict occurrence of osteoporotic fractures. Br Med J 312:1254–1259Google Scholar
- 10.Kreiger N, Tenenhouse A, Joseph L et al (1999) The Canadian Multicenter Osteoporosis Study (CaMos): background. Rationale. Methods. Canadian J Aging 18:376–387Google Scholar
- 14.Felsenberg D, Silman AJ, Lunt M, Ambrecht G, Ismail AA, Finn JD, Cockerill WC, Banzer D, Benevolenskaya LI, Bhalla A, Bruges Armas J, Cannata JB, Cooper C, Dequeker J, Eastell R, Ershova O, Felsch B, Gowin W, Havelka S, Hoszowski K, Jajic I, Janot J, Johnell O, Kanis JA, Kragl G, Lopez Vaz A, Lorenc R, Lyritis G, Masaryk P, Matthis C, Miazgowski T, Parisi G, Pols HAP, Poor G, Raspe HH, Reid DM, Reisinger W, Scheidt–Nave C, Stepan J, Todd C, Weber K, Woolf AD, Reeve J, O’Neill TW (2002) Incidence of vertebral fracture in Europe: results from the European Prospective Osteoporosis Study (EPOS). J Bone Miner Res 17:716–724PubMedCrossRefGoogle Scholar
- 15.Ismail AA, Pye SR, Cockerill WC, Lunt M, Silman AJ, Reeve J, Banzer D, Benevolenskaya LI, Bhalla A, Bruges Armas J, Cannata JB, Cooper C, Delmas PD, Dequeker J, Dilsen G, Falch JA, Felsch B, Felsenberg D, Finn JD, Gennari C, Hoszowski K, Jajic I, Janott J, Johnell O, Kanis JA, Kragl G, Lopez Vaz A, Lorenc R, Lyritis G, Marchand F, Masaryk P, Matthis C, Miazgowski T, Naves–Diaz M, Pols HAP, Poor G, Rapado A, Raspe HH, Reid DM, Reisinger W, Scheidt–Nave C, Stepan J, Todd C, Weber K, Woolf AD, O’Neill TW (2002) Incidence of limb fracture across Europe: results from the European prospective osteoporosis study (EPOS). Osteoporos Int 13:565–571CrossRefPubMedGoogle Scholar
- 24.O´Neill TW, Lunt M, Felsenberg D, Benevolenskaya LI, Bhalla AK, Cannata JB, Cooper C, Crabtree N, Dequeker J, Hoszowski K, Jajic I, Kanis JA, Kragl G, Lopes Vaz A, Lorenc R, Lyritis G, Masaryk P, Miazgowski T, Parisi G, Pols HAP, Poor G, Reid DM, Scheidt–Nave C, Stepan J, Todd C, Weber K, Woolf AD, Reeve J (2002) The relationship between bone density and incident vertebral fracture in men and women. J Bone Miner Res 17:2214–2221PubMedCrossRefGoogle Scholar