Abstract:
Introduction Fracture risk assessment algorithm (FRAX)
is the most validated method available to predict fracture
risk. Its use is restricted due to limited availability of Dual
Energy X-ray Absorptiometry (DXA). FRAX has the option
of assessing fracture risk without bone mineral density
(BMD) data.
Objectives To assess the ability of Sri Lankan FRAX
algorithm without BMD input in evaluating fracture risk.
The possibility of replacing the BMD input with Quan titative Ultrasound (QUS) data of radius in calculating
fracture risk also assessed.
Methods Data of clinical risk factors associated with
fractures were collected from community dwelling
postmenopausal women (n=339). DXA scans were
performed in all subjects and QUS scans (in radius)
were performed in a randomly selected sample (n=207).
Ten-year risks of major osteoporotic fracture (MOFR)
and hip fracture (HFR) were calculated with BMD, without
BMD (FRAX-FN0
) and with QUS T score instead of BMD
(FRAX-UST).
Results and conclusion Nearly 35.7% had high risk of
fractures. FRAX-FN0
had 79.2% sensitivity, 80.1%
specificity, 68.8% positive predictive value (PPV) and
87.4% negative predictive value (NPV). FRAX-UST
showed 78.4% sensitivity, 70% specificity, 59.8% PPV
and 85% NPV. ROC AUCs were above 0.80 in both FRAX FN0
and FRAX-UST. The standard errors of estimate
(SEE) were less in FRAX-FN0
(3.96 and 2.76 for MOFR FN0
and HFR-FN0
respectively) compared to FRAX-UST
(6.13 and 4.83 for MOFR-UST and HFR-UST, res pectively). In conclusion, Sri Lankan FRAX without BMD
is an acceptable alternative in areas with restricted DXA
facility. Radial QUS data cannot be used as a substitute
to FN-BMD in Sri Lankan FRAX.
