Considerations of Kanis et al for Determining the Economic Threshold for Treating Osteoporosis in a Post-Menopausal Woman

 

Factors to consider:

(1) social and cultural factors in a country

(2) cost of osteoporotic complications in a society

(3) cost of interventions to prevent the fracture

(4) economic resources available

(5) how bone density is measured

(6) what fracture risk is being targeted

 

The decision to treat can be based on:

(1) the age of the patient and the 10 year fracture probability

(2) bone density, age and clinical history of history of fracture

 

For the United Kingdom, a variety of thresholds for treatment were identified that are cost effective. Other countries or populations may select different thresholds. These thresholds will change over time.

 

Clinical rules - one or more of the following:

(1) age >= 65 years AND history of prior osteoporotic fracture

(2) age >= 60 years AND T-score at femoral neck -2.5

(3) history of prior osteoporotic fracture AND T-score at femoral neck -2.5

(4) T score at femoral neck < -2.5

 

The authors also determined the 10 year hip fracture probability at which treatment became cost effective. The thresholds were based on the bone density at the femoral neck and included considerations of osteoporotic fracture risk at other sites .

Age	10 Year Probability of Hip Fracture
50	1.1
55	1.8
60	2.6
65	3.7
70	5.2
75	6.9
80	8.5
85	9.0

 

This data can be approximated by:

 

Age	Threshold in percent
50 to 75	(0.005314 * ((age)^2)) - (0.4346 * (age)) + 9.574
75 to 80	(0.33 * (age)) - 17.88
80 to 85	(0.094 * (age)) + 1
85 to 90	(-0.374 * (age)) + 40.78