A DEXA scan result boils down to one critical number: your T-score. If that number is -1.0 or above, your bone density is considered normal. A T-score between -1.0 and -2.5 means you have low bone density, a condition called osteopenia. And a T-score of -2.5 or below is the threshold for an osteoporosis diagnosis. To put that in practical terms, if you are a 68-year-old woman who just got a T-score of -1.8 at the hip, you fall into the osteopenia range — your bones are thinner than ideal but not yet at the osteoporosis stage.
That single number, however, does not tell the whole story, and misunderstanding it can lead to either unnecessary panic or dangerous complacency. Your T-score compares your bone mineral density to that of a healthy 30-year-old adult of the same sex — essentially measuring how far you have drifted from peak bone mass. But the report also includes a Z-score, the specific skeletal sites that were measured, and context that only makes sense when you understand how fracture risk actually works. For people caring for a loved one with dementia, bone density results carry extra weight: falls are more common, fracture recovery is harder, and the medications involved require careful coordination with existing treatment plans. This article walks through exactly what each number on your DEXA report means, how fracture risk is calculated beyond the T-score alone, who should be getting screened and how often, what current treatment options look like in 2026, and what these results mean specifically for older adults living with cognitive decline.
Table of Contents
- What Do the Numbers on a DEXA Scan Report Actually Mean?
- Which Skeletal Sites Matter Most and Why Results Can Vary Between Them
- How Fracture Risk Is Calculated Beyond the T-Score
- Who Should Get Screened and How Often
- Current Treatment Options and Their Real-World Limitations
- What a DEXA Scan Costs and How to Get One Covered
- The Growing Scope of Osteoporosis and What Lies Ahead
- Conclusion
- Frequently Asked Questions
What Do the Numbers on a DEXA Scan Report Actually Mean?
The DEXA scan — short for Dual-Energy X-ray Absorptiometry — is the gold-standard test for measuring bone mineral density. It uses low-dose X-rays to examine specific skeletal sites, most commonly the lumbar spine (L1 through L4), the femoral neck and total hip, and sometimes the forearm. The whole process is painless, non-invasive, and takes roughly 10 to 20 minutes. What you get back is a report with two key metrics: a T-score and a Z-score. The T-score follows World Health Organization criteria and is the primary number used for diagnosis in postmenopausal women and men over 50. It is measured in standard deviations from the bone density of a healthy young adult. Here is the critical part that many patients miss: the risk of fracture doubles with every single standard deviation decrease below normal.
That means a person with a T-score of -2 does not just have slightly weaker bones than someone at 0 — they have roughly four times the fracture risk. A T-score of -3 means eight times the risk. The scale is not linear in its consequences, even though the numbers look modest on paper. The Z-score works differently. It compares your bone density to the average for someone of your same age, sex, race, height, and weight. A Z-score of -2.0 or lower is flagged as “below the expected range for age” and often signals that something beyond normal aging is driving the bone loss — medication side effects, hormonal disorders, or nutritional deficiencies. Z-scores are the preferred metric for children, premenopausal women, and men under 50, because for these groups a low T-score might simply reflect that they have not yet reached peak bone mass rather than indicating disease.
Which Skeletal Sites Matter Most and Why Results Can Vary Between Them
Your DEXA report will typically show separate scores for different body sites, and it is not unusual for those numbers to disagree with each other. You might have a normal T-score at the spine but osteopenia at the hip, or vice versa. This is not an error — different bones lose density at different rates depending on your age, activity level, and the specific biological processes at work. The lumbar spine is the most sensitive site for detecting early bone loss and for tracking how well treatment is working over time. If your doctor wants to see whether a medication is rebuilding bone, the spine is usually where changes show up first.
The femoral neck and total hip, on the other hand, are the best predictors of hip fracture risk and are the measurements used in the FRAX fracture risk calculator. For diagnosis purposes, clinicians typically use whichever site shows the lowest T-score. The forearm, specifically the distal radius, is a backup site used when the hip or spine cannot be accurately measured — for example, in someone who has had bilateral hip replacements. However, there is an important limitation for people with spinal arthritis or degenerative changes, which are common in older adults. Bone spurs and calcified discs can artificially inflate the spine T-score, making bone density appear better than it actually is. If your loved one has significant spinal arthritis, ask the ordering physician whether the spine results are reliable or whether the hip score should carry more weight in the clinical decision.
How Fracture Risk Is Calculated Beyond the T-Score
A T-score alone does not determine whether someone needs treatment. Two people with identical T-scores can have vastly different fracture risk depending on their age, weight, medication history, and whether they have already broken a bone. This is where the FRAX tool comes in — the Fracture Risk Assessment Tool, developed by the World Health Organization, calculates the 10-year probability of a major osteoporotic fracture using bone density data plus a set of clinical risk factors including age, sex, BMI, smoking status, alcohol use, prior fractures, parental hip fracture history, and use of glucocorticoids. Treatment is generally recommended when FRAX shows a 20 percent or greater risk of a major osteoporotic fracture over the next 10 years, or a 3 percent or greater risk of hip fracture specifically. Consider a concrete example: a 72-year-old woman with a femoral neck T-score of -2.0 and no other risk factors might have a 10-year major fracture risk around 13 percent — below the treatment threshold.
But add a history of a prior wrist fracture and long-term corticosteroid use, and that number could jump above 25 percent, firmly in the range where medication is warranted. For dementia caregivers, the FRAX calculation takes on particular significance. Cognitive impairment is not one of the standard FRAX inputs, but it dramatically increases fall risk, which in turn increases actual fracture probability beyond what FRAX predicts. A person with moderate Alzheimer’s disease and a T-score in the osteopenia range may face real-world fracture risk comparable to someone with frank osteoporosis. Discuss this explicitly with the physician — the treatment threshold may need to be adjusted downward for patients with significant cognitive decline.
Who Should Get Screened and How Often
Screening guidelines changed with the updated January 2025 recommendations from the U.S. Preventive Services Task Force. The USPSTF now gives a Grade B recommendation for osteoporosis screening with DEXA in all women aged 65 and older, as well as in postmenopausal women under 65 who are at increased fracture risk. For men, however, the task force found insufficient evidence to recommend for or against routine screening — a gap that frustrates many clinicians, since about 4.2 percent of men over 50 have osteoporosis and men account for roughly one-third of all hip fractures. The tradeoff here is real. Screening too early in low-risk populations leads to overdiagnosis and unnecessary anxiety. Screening too late means catching osteoporosis only after a fracture has already occurred.
For caregivers managing a loved one with dementia, there is a practical argument for earlier and more frequent screening regardless of the formal guidelines. Dementia increases fall risk by two to three times compared to cognitively intact older adults. A baseline DEXA scan at the time of a dementia diagnosis — even if the person would not otherwise meet screening criteria — gives you a reference point that can guide fall prevention strategies and inform decisions about medications that might accelerate bone loss. How often to repeat the scan depends on the initial results. For someone with normal bone density and no significant risk factors, repeat scanning every 10 to 15 years may be sufficient. For someone with osteopenia, every two to three years is more typical. And for someone on osteoporosis treatment, follow-up scans are usually done every one to two years to assess whether the medication is working.
Current Treatment Options and Their Real-World Limitations
Treatment of osteoporosis in 2026 follows a risk-stratified approach. For most patients diagnosed with osteoporosis, first-line therapy remains bisphosphonates — medications like alendronate, risedronate, or intravenous zoledronic acid. Oral bisphosphonates are typically prescribed for five years, and IV zoledronic acid for three years, after which the physician reassesses whether to continue, switch, or take a drug holiday. For patients at very high fracture risk — meaning very low T-scores, multiple prior fractures, or fractures that occurred despite bisphosphonate therapy — current guidelines now recommend starting with an anabolic agent first. Romosozumab (brand name Evenity) or teriparatide (Forteo) is used for one to two years to actively build new bone, and then the patient transitions to a bisphosphonate to maintain those gains.
Denosumab (Prolia), given as a subcutaneous injection every six months, is an alternative when bisphosphonates are contraindicated. Here is the warning that matters most for dementia care: bisphosphonates require specific administration protocols — the patient must take them on an empty stomach with a full glass of water and remain upright for at least 30 minutes afterward. For someone with moderate to advanced dementia who has difficulty following multi-step instructions or who tends to lie down after taking pills, this can be impractical or even dangerous due to esophageal irritation risk. Injectable options like zoledronic acid (once yearly) or denosumab (twice yearly) may be far more realistic. However, denosumab carries its own risk: if it is discontinued without transitioning to another medication, rapid bone loss can occur, sometimes worse than baseline. Any treatment plan must account for the realities of the patient’s cognitive and functional status.
What a DEXA Scan Costs and How to Get One Covered
Out-of-pocket costs for a DEXA scan range from about 40 dollars to over 300 dollars, depending on where you go. Hospital-based scans tend to run 300 dollars or more, while community or fitness-oriented providers like BodySpec offer scans for as low as 40 to 45 dollars with a membership. Most private insurance plans and Medicare cover bone density scans when ordered for osteoporosis diagnosis or monitoring, and DEXA scans are HSA and FSA eligible regardless of the reason for the scan.
For caregivers weighing whether to pursue screening for a loved one who may not fully understand what is happening during the scan, the practical barriers are low. The test involves lying still on a padded table for 10 to 20 minutes with no injections or enclosed spaces. Most people with mild to moderate dementia tolerate it well, particularly if a familiar caregiver is present in the room. The information gained — a concrete, objective measure of fracture risk — is well worth the modest cost and effort.
The Growing Scope of Osteoporosis and What Lies Ahead
The numbers paint a stark picture of where things are headed. An estimated 10 million Americans aged 50 and older currently have osteoporosis, with an additional 44 million living with low bone density. Overall prevalence in adults over 50 stands at 12.6 percent — roughly 1 in 8. Among women over 50, that figure is 18.8 percent, and it climbs to 27.1 percent in women over 65.
The total number of osteoporosis cases in the United States is projected to increase by over 30 percent by 2030, driven by an aging population. For the dementia care community, this trajectory means that bone health will increasingly become a routine part of comprehensive care planning. Research into the overlap between osteoporosis and neurodegeneration continues to evolve, with emerging evidence suggesting shared mechanisms involving inflammation, hormonal changes, and reduced physical activity. As screening tools become more accessible and treatment options expand, the goal for caregivers should be straightforward: know the numbers, understand what they mean, and use them to prevent the fractures that so often mark the beginning of a steep decline in quality of life for people already navigating cognitive impairment.
Conclusion
Your DEXA scan results are not just abstract numbers — they are a concrete, actionable measure of how vulnerable your bones are to fracture. A T-score of -1.0 or above means normal density. Between -1.0 and -2.5 is osteopenia. At -2.5 or below, you are in osteoporosis territory, and fracture risk doubles with each standard deviation of decline.
But the T-score alone is not the full picture. The specific skeletal sites measured, the Z-score, clinical risk factors fed into the FRAX calculator, and the patient’s real-world fall risk all shape the treatment decision. For anyone caring for a person with dementia, bone density screening deserves a place on the care planning checklist alongside cognitive assessments and medication reviews. Falls are among the most common and most consequential complications of dementia, and knowing whether osteoporosis is compounding that risk changes the calculus on everything from home safety modifications to medication choices. Talk to the physician about getting a baseline DEXA scan, understand what the scores mean, and advocate for a treatment plan that accounts for both the bones and the brain.
Frequently Asked Questions
How often should someone with dementia get a DEXA scan?
There is no dementia-specific guideline, but for older adults with osteopenia or osteoporosis, repeat scans every one to three years are typical. Given the elevated fall risk in dementia, a baseline scan at diagnosis and follow-ups every two years is a reasonable approach to discuss with the physician.
Can osteoporosis medications interact with dementia drugs?
Bisphosphonates and cholinesterase inhibitors (like donepezil) do not have direct drug interactions. However, the practical demands of oral bisphosphonate administration — empty stomach, staying upright for 30 minutes — can be difficult for dementia patients. Injectable alternatives like zoledronic acid or denosumab avoid this problem entirely.
Is a Z-score or T-score more important for older adults?
For postmenopausal women and men over 50, the T-score is the primary diagnostic metric. The Z-score becomes important if it falls below -2.0, which may indicate that bone loss is being driven by something beyond normal aging, such as a medication side effect or hormonal disorder that warrants investigation.
Does Medicare cover DEXA scans?
Yes. Medicare covers bone density testing for beneficiaries who meet certain criteria, including postmenopausal women and individuals on long-term steroid therapy. Most diagnostic DEXA scans ordered by a physician for osteoporosis evaluation are covered. DEXA scans are also HSA and FSA eligible.
What if the DEXA scan shows different scores at different body sites?
This is common and expected. The lumbar spine may show different density than the hip due to differences in bone composition and age-related changes. Clinicians typically base the diagnosis on the lowest T-score among the measured sites, but arthritis in the spine can falsely elevate that score, so the hip measurement sometimes carries more clinical weight in older adults.
