MORES Power to You

MORES Power to You

Abstract & Commentary

By Allan J. Wilke, MD

Professor and Chair, Program Director, Department of Family Medicine, Western Michigan University School of Medicine, Kalamazoo

Dr. Wilke reports no financial relationships relevant to this field of study.

Synopsis: A simple decision support tool can help identify which men should be screened with dual-
energy x-ray absorptiometry (DEXA) for osteoporosis.

Source: Cass AR, Shepherd AJ. Validation of the Male Osteoporosis Risk Estimation Score (MORES) in a primary care setting. J Am Board Fam Med 2013;26:436-444.

This cross-sectional study’s purpose was to validate the Male Osteoporosis Risk Estimation Score (MORES) in a primary care setting; it had been previously validated in the National Health and Nutrition Examination Survey (NHANES) III.¹ The subjects were men who were attending the University of Texas Medical Branch, Galveston, family medicine, general internal medicine, and geriatric medicine outpatient clinics from 2008-2011. Inclusion criterion was age ≥ 60 years. Excluded were men with a history of osteoporosis, bone disease, or bilateral hip replacement; men who were taking bone-conserving medications (e.g., bisphosphonates); and men who weighed > 300 pounds (the DEXA scanner couldn’t handle them).

The investigators enrolled 386 men: 40, who did not report for the DEXA scan, were excluded, leaving 346. They were an average age of 70 years with a mixed ethnic population (white, black, Hispanic, and Asian). The criterion for osteoporosis was a T-score ≤ -2.5 at the femoral neck or the total hip. Using this, 15 men (4.3%) met the criterion. An additional 19 had severe osteopenia. The rates of other potential risk factors for osteoporosis (previous fragility fracture, history of rheumatoid arthritis, heavy alcohol use, chronic obstructive pulmonary disease [COPD], and glucocorticoid use) were all < 10%.

How did MORES perform? The table below gives the raw data from which the sensitivity and specificity were calculated.

The sensitivity was 0.80 (95% confidence interval [CI], 0.52-0.96), and the specificity was 0.70 (95% CI, 0.64-0.74). About one-third (32.1%) of all subjects were MORES positive. The authors calculate that the number needed-to-screen (NSS) and to be referred for DEXA to prevent one additional hip fracture (assuming treatment over 10 years) was 654 (95% CI, 485-1132). Universal DEXA screening had an NSS of 1604.

COMMENTARY

MORES has been around for 7 years now. The authors of that study, two of whom authored this one, did logistic regression modeling to choose the variables that yielded a good fit to the data, and then simplified it. MORES is ridiculously easy to score. It considers just three variables: age, weight, and history of COPD. Points are awarded as described in the table below. A positive score is ≥ 6.

As we have previously discussed in Internal Medicine Alert, a really good clinical decision tool is 95% sensitive and 95% specific.² Sensitivity (or true positive rate) measures the proportion of people identified with a condition to those who truly have it. Specificity (or true negative rate) measures the proportion of people identified as not having a condition to those who truly don’t. MORES doesn’t quite make the grade of "really good," coming up short on the specificity side. (The 95% CI for sensitivity contains 95%, so it is possible that sensitivity could be "really good.")

This is a good time to review what, according to the Frame Criteria, makes a good screening test.

1. The disease must have a significant effect on quality or quantity of life.
2. Acceptable methods of treatment must be available.
3. The disease must have an asymptomatic period during which detection and treatment significantly reduce morbidity and/or mortality.
4. Treatment in the asymptomatic phase must yield a therapeutic result superior to that obtained by delaying treatment until symptoms appear.
5. Tests must be available at reasonable cost to detect the condition in the asymptomatic period.
6. The incidence of the condition must be sufficient to justify the cost of screening.

How do osteoporosis and MORES stack up? Osteoporosis, especially if it results in a fracture, can have a significant effect on quality and quantity of life. In fact, men do worse than women after a hip fracture.⁴ Acceptable methods of treatment are available for women, but the evidence that the same methods are effective in men is not as extensive.⁵ Osteoporosis does have an asymptomatic period, and treating it during this period is better than waiting for a fracture, at least in women. Administering MORES is very inexpensive, especially if it’s self-administered or done by a medical assistant; a DEXA costs about $200 if your patient doesn’t have insurance.⁶ In this study, the incidence of osteoporosis was 4.3%. In the NHANES 2005-2006, it was 2% at the femoral neck in men and 10% in women.⁷ Whichever number you choose, the low cost of administering MORES makes screening cost-effective. Although one-third of the subjects would have been referred for DEXA, two-thirds wouldn’t have and < 1% (3/346) would have been missed.

The U.S. Preventive Services Task Force, my go-to source for screening advice, has currently concluded that there is not enough evidence to recommend for or against male osteoporosis screening.⁸ Ideally, before I would recommend adopting it, there would be a number of randomized, controlled studies of MORES to "pre-screen" for osteoporosis in men, and they would have fracture prevention as the primary outcome. That would be a long wait. In the meantime, I think we can extrapolate from the screening and treatment trials of osteoporosis in women and use MORES for men.

References

1. Shepherd AJ, et al. Ann Fam Med 2007;5:540-546.
2. Wilke AJ. Internal Medicine Alert 2006;28:97-99.
3. Frame PS, Carlson SJ. J Fam Pract 1975;2:29-36.
4. Haentjens P, et al. Ann Intern Med 2010;152:380-390.
5. Mosekilde L, et al. Drugs 2013;73:15-29.
6. http://www.medicinenet.com/bone_density_scan/page6.htm. Accessed September 3, 2013.
7. Looker AC, et al. J Bone Miner Res 2010;25:64-71.
8. http://www.uspreventiveservicestaskforce.org/uspstf/uspsoste.htm. Accessed September 3, 2013.