Bone Mineral Density What is a bone mineral density test? Who gets this test done? Why is it needed? How many different types? What do the results mean? Bone Mineral Density HHHOLDORF

What is a bone mineral density test? A bone mineral density test or BMD measures how much calcium and other types of minerals are in an area of your bone. It is usually done to help your health care provider detect osteoporosis and to predict the risk of bone fractures. Osteoporosis is characterized by progressive loss of bone density, thinning of bone tissue and increased vulnerability to fractures. May result from disease, dietary or hormonal deficiency or advanced age

Who gets this test done? You should have a BMD test or screening done if you are at increased risk for osteoporosis You are more likely to get osteoporosis if you are A man over 70 A woman over 65 Women under 65 and men the ages between 50-70 are at increased risk of osteoporosis if: A broken bone, caused by normal activities, such as a fall from standing height or lower Chronic rheumatoid arthritis, chronic kidney disease, eating disorders Early menopause Smoking Loss of height due to compression fractures in the back Strong family history of osteoporosis 3 or more alcoholic beverages per day on most days Taking corticosteroid medications everyday for more than 3 months

Why is it needed? Bone mineral density tests are used to: Diagnose bone loss and osteoporosis See how well you are responding to osteoporosis medication Predict the risk of future bone fractures

How many different types? Bone density testing can be done several different ways. Most common and accurate way uses a dual-energy x-ray absorptiometry (DEXA) scan. It uses lose-dose x-rays You receive more radiation with a chest x-ray 2 different types of DEXA scans: Central DEXA. You lay on a soft table while the scanner passes over your lower spine and hip. Best to predict bone fractures. Peripheral DEXA. These are smaller machines which measure the bone density in your wrist, fingers legs or heel.

What do the results mean? Normal results: Results are reported as a T-score and Z-score T-score compares your bone density results to a healthy, generally 30 year old of the same gender Z-score compares your bone density results to other people your age, race and gender With either score, a negative number means your bones are thinner. The more negative a number, the more apt the bones are to fracture. A normal T-score range is between -1.0 and above.

What do the results mean? Cont’d Bone density tests DO NOT diagnose bone fractures. It helps predict, along with other factors, the risk of a bone fracture in the future. -1 to -2.5 signifies the beginning of bone loss (osteopenia) -2.5 or greater indicates osteoporosis Hoffman, Matthew MD. “Living with Osteoporosis” WebMD. 3 June, 2013. http://www.webmd.com/osteoporosis/living-with-osteoporosis-7/tests Strock, Susan MD. “Bone Mineral Density Test” Medline Plus. 3 June, 2013. http://www.nlm.nih.gov/medlineplus/ency/article/007197.htm

History of Bone Mineral Density Measurement

BMD measurement dates back as far as the 1940s’ It was measured using a plain radiograph (x-ray) It was noted that bone lost was not apparent on an x-ray film until the patient lost approximately 40% bone mass, making it too late to treat

In 1960, a young medical physics professor from the University of Wisconsin invented bone densitometry. Bone densitometry is the measurement of bone mineral content utilizing a precise amount of radiation. Since the radiation doses were in small amount, often his graduate students would volunteer to be research subjects. He discovered that lactating mothers had a small change in their bone mineral, thus making it impetrative for young mothers to supplement during lactating years.

One of Johns’ early bone densitometry publications (Invest. Radio One of Johns’ early bone densitometry publications (Invest. Radio. 3:141; 1968) was listed as its single most cited article on the 25th anniversary of Investigative Radiology.

why the scan was invented As we get older we all loss some bone mass Therefore making them (bones) less dense and porous This can happen to men, but is more prevalent in women who are65 or older . Our bones become thinner, and this is called osteopenia It makes the bones lighter and weaker, and a chance of breaking The bone density scan was invented to help measure When this occurs, our bones lose calcium and other important minerals (due to hormonal decline) Osteopenia leads to osteoporosis The amount of matter in bone, sucked out as calcium. This kind of info.dr can determine the strength in someone's bone mass, and if they are at risk for a fracture

John was deeply concerned with excess radiation exposures in diagnostic radiology. He developed simple test tools and techniques to measure radiation and to evaluate the quality of x-ray images. These efforts led to the creation of Radiation Measurements, Inc. (RMI), a pioneering manufacturer in quality-assurance measurements, materials, and devices. This also led to product developments by several companies and to several standard techniques for radiation measurement and image quality assurance. The Lunar Radiation was developed by GE in the late 90s’ and was an extension of what John Cameron developed some 30 years prior http://hps.org/aboutthesociety/people/inmemoriam/JohnCameron.html John died on 16 March 2005 at age 82 in Gainesville, Florida, where he lived during the winter months and served as a Visiting Professor in the Department of Radiation Oncology at the University of Florida.

Case Study Patient History A 60-year-old Caucasian female is in for an annual checkup. The patient experienced menopause in her early 50’s and has been in good health. Other than hormone therapy (HT) the patient is on no other medications. The patient has no history of fractures, stands at 5’7”. 112 lbs. and rarely exercises. Smokes cigarettes and is a regular coffee drinker. Although no personal injuries, her sister has past experience of a hip fracture.

Risk Factors Although the patient has no history of fractures, she does have characteristics that put her at higher risk of fractures significantly seen in Caucasian women. Risk factors which may increase fractures: Increased fractures as an adult Family history of fractures Low body weight (Less that 130 lbs.) Smoking

Patient Evaluation After annual checkup, no abnormalities were found. No signs of loss of height were noted Patient’s vitamin D and calcium levels remained consistent with past examinations Although there were no abnormalities during checkup, BMD testing was recommended due to normal risk factors with age.

BMD Test Results BMD tests reveled a left hip T-score of -1.5, which is considered a fairly low score and prompted consideration of what could be causing a low score and bone-loss. All other test results were said to be normal, including normal serum thyrotropin, serum 35-hydroxyviatmin D, and cortisol levels. With a low T-score for the hip, the patient is considered to have low BMD, also known as osteopenia, which increases the patient’s risk for future fractures.

Recommended Preventative Strategies and Treatment for Osteopenia Patient is highly encouraged to quit smoking – women smokers are typically thinner and undergo menopause at an early age, there is a higher risk facture for fractures Calcium supplements are recommended to ensure intake of daily calcium requirements – about 500 mg at a time Weight-bearing exercise is highly recommended to build muscle mass and tone for protection. Although swimming is not weight-bearing, many patients chose swimming to improve strength without high impact risk. Fall prevention- Studies have proved that over 90% of hip and wrist fractures are results of a fall, so taking measures to reduce the risk of falls in your home and work are recommended – especially for elderly

Hormone Therapy Controlled studies have demonstrated that hormone therapy has decreased vertebral fractures by at least one/third Hormone therapy has decreased overall fractures by 24-30% Although hormone therapy is effective, it is not recommended as the sole treatment or used for disease prevention – there can be risk factors such as stroke, cognitive impairment, and deep vein thrombosis Increased risk of breast cancer can also be seen in HT

Patient Summary With risk factors included in HT, the patient discontinued use. Discontinue raises the patient’s risk up to 4% in the first year for increased BMD Patient is recommended calcium and vitamin D supplements, and adequate daily exercise to increase body mass.