Este estudio tiene la fortaleza de reunir sobre 16.500 pacientes de un distrito provincial, lo que hace que tengan baja tasa de abandono en el seguimiento, pero tiene la debilidad de no detectar las fracturas leves y desconocer la verdadera prevalencia de fracturas vertebrales, que a menudo son subclínicas y/o no informadas.

Los resultados son bastante parecidos a los de Marshall y cols. en 1996, con quien los autores comparan sus resultados .

Las pacientes tienen en promedio 65 años (±14) y son observadas por un período entre 1,7 y 4,7 años.

Encuentran buen valor predictivo tanto para fracturas en el mismo sitio medido como para estimar el riesgo de sufrir fracturas en localizaciones diferentes a la medida directamente.

Pero hay diferencias: las densitometrías de cadera predicen mejor las fracturas de la propia cadera y también las de otros sitios tales como muñeca y columna, que las mediciones de columna lumbar,

Esto se explicaría porque con la edad se distorsiona la densitometría vertebral debido a espondiloartrosis y esclerosis, lo que subestima la predicción del riesgo local y sistémico.

 

En el artículo hay una tabla ROC y un gráfico muy descriptivo.

J Clin Endocrinol Metab. 2007 Jan;92(1):77-81. Epub 2006 Oct 10.        

Effectiveness of bone density measurement for predicting osteoporotic fractures in clinical practice.

Leslie WD, Tsang JF, Caetano PA, Lix LM.

Department of Medicine (C5121), 409 Tache Avenue, Winnipeg, Manitoba, Canada R2H 2A6. bleslie@sbgh.mb.ca.

Context: Bone density measurement with dual-energy x-ray absorptiometry is widely used for fracture risk assessment. It has not been established that published gradients of fracture risk from study populations can be directly applied to clinical populations. Objective: The objective of the study was to assess osteoporotic fracture prediction with dual-energy x-ray absorptiometry in a large clinical cohort. Design: This was a historical cohort study (mean observation period 3.2 +/- 1.5 yr). Patients: The study population was drawn from the population-based database of the Manitoba Bone Density Program. Analyses were limited to women aged 50 yr or older at baseline (n = 16,505). Main Outcome Measure: Each subject's longitudinal health service record was assessed for the presence of nontrauma fracture codes (hip, spine, wrist, and humerus) after bone density testing. Age-adjusted hazard ratios for fracture were derived from Cox proportional hazards models. Results: Site-specific and overall fracture rates were significantly associated with each site of bone density measurement (all P < 0.00001). The 95% confidence intervals overlapped those from a widely cited metaanalysis of fracture prediction from different sites. Although fracture prediction was not significantly different between the three hip measurement sites, each hip site was better than the lumbar spine for predicting overall fractures (nonoverlapping 95% confidence intervals). The manufacturer sd (equivalent to a unit change in T-score) resulted in a significantly smaller gradient of risk for the spine than when the population sd was used. Conclusions: Bone density measurements are effective for predicting fractures in clinical practice. However, hip measurements were superior to the spine in overall osteoporotic fracture prediction.