- Kenny Lin, MD, MPH
Hip fractures are a significant preventable cause of morbidity and mortality in older adults. Strategies to reduce hip fracture rates include preventing falls, screening for osteoporosis and prescribing bisphosphonate drugs to increase low bone density, and vitamin D supplementation. Recent studies and guidelines have clarified some of the evidence surrounding hip fracture prevention.
In a Putting Prevention Into Practice case study in the August 15 issue of American Family Physician, Drs. Tina Fan and Elizabeth Erickson discussed two updated U.S. Preventive Services Task Force (USPSTF) recommendations on interventions to prevent falls and supplements for primary prevention of fractures. Although the USPSTF continues to recommend exercise interventions to prevent falls in community-dwelling adults 65 years or older at increased risk of falls, it no longer recommends vitamin D supplements to prevent falls, due to evidence of no benefit and potential harms (increased falls and kidney stones). The Task Force found insufficient evidence to assess the balance of benefits and harms of vitamin D and calcium supplements at daily doses greater than 400 IU of vitamin D and 1,000 mg of calcium (lower doses are not effective) in postmenopausal women without a history of osteoporosis, which may come as a surprise, given how many are taking such supplements.
The USPSTF also recently reaffirmed its previous recommendation to screen for osteoporosis with bone measurement testing in women 65 years and older. Earlier this year, The Lancet published the first randomized controlled trial of osteoporosis screening with fracture outcomes. Although screening did not affect the primary outcome of all osteoporosis-related fractures over 5 years (HR 0.94, 95% CI 0.85-1.03), it reduced the incidence of hip fractures (HR 0.72, 95% CI 0.59-0.89). More controversial was the Task Force's recommendation to screen postmenopausal women younger than 65 years at increased risk for osteoporosis. In a JAMA editorial, Dr. Margaret Gourlay (a family physician and former AFP editor), argued that the 2-step screening strategy advised by the USPSTF - clinical risk assessment tool followed by bone density testing if indicated - may not produce a net benefit to patients. Although screening women younger than age 65 has potential benefits, it is unclear if these benefits outweigh the opportunity costs:
If complicated risk tools perform no better than age alone to identify screening candidates, women younger than 65 years may be subjected to inefficient screening procedures. … The clinician could spend half of a 15-minute clinical visit accessing a risk tool and asking the patient about unfamiliar risk factors (eg, secondary causes of osteoporosis) to make 1 decision out of the dozen or more compressed into an annual physical examination. … Given the myriad responsibilities of primary care practices caring for patients with high-acuity conditions, implementation of screening programs that are needlessly complex is burdensome and distracts from high-value medical care.
Finally, for patients with osteoporosis who are eligible for treatment, given concerns about long-term adverse effects of bisphosphonates, including rare osteonecrosis of the jaw, for how long should these drugs be prescribed? A FPIN Help Desk Answer found low-quality evidence that for most women, bisphosphonate therapy beyond 5 years does not further reduce clinical vertebral fractures, nonvertebral fractures, or mortality. However, women with persistent femoral neck T-scores lower than -2.5 may benefit from longer treatment durations.