The previous article about osteoporosis discussed the huge burden of this disease, and how important it is to treat patients with the diagnosis to prevent fractures.
Let’s look at some questions that many women ask.
What are the risk factors for osteoporosis?
When should you get your first scan and how often thereafter?
What is a dexa scan?
How do you interpret the results?
What is a FRAX score?
The typical women who has osteoporosis is Caucasian or Asian, menopausal and small-framed. Women are 4 times more likely than men to get osteoporosis, and they live longer which is another risk. Family history is extremely significant, as your bone structure is largely inherited. If your parent or grandparent broke a hip, your risk increases. Lifestyle with exercise and diet does make a difference, but probably less so than heredity. A history of fractures must be evaluated. Certain disease and medications increase the risk. Smoking and heavy use of alcohol also decrease the bone density.
Here is a list of medical conditions that increase the risk of osteoporosis:
Rheumatic and autoimmune diseases: ankylosing spondylitis, lupus, rheumatoid arthritis
Endocrine disorders: adrenal insufficiency, Cushing’s disease, diabetes, hyperparathyroidism, thyrotoxicosis
Gastrointestinal disorders: celiac disease, gastric bypass, GI surgery, inflammatory bowel disease, malabsorption, pancreatic disease, primary biliary cirrhosis
Lifestyle factors: low calcium intake, high caffeine intake, alcohol (3 or more drinks per day), active or passive smoking, high salt intake, sedentary lifestyle, falling, excess Vitamin A, aluminum from antacids, immobilization, being thin
Medications: anticoagulants (heparin), anticonvulsants, aromatase inhibitors, barbiturates,chemotherapy, glucocorticoids like prednisone, lithium, gonadotropin releasing hormone agonists, medroxyprogesterone acetate
Genetic factors: cystic fibrosis, hemochromatosis, Marfans, osteogenesis imperfecta,
parental history of hip fractures,
Hypogonadal states: anorexia, bulimia, athletic amenorrhea, hyperprolactinemia,
premature ovarian failure, menopause, Turner’s syndrome
Miscellaneous conditions: alcoholism, congestive heart failure, depression, emphysema, end stage renal disease, epilepsy, scoliosis, multiple sclerosis, muscular dystrophy, prior fracture as an adult, leukemia, lymphoma, multiple sclerosis, sickle cell anemia, and thalassemia
When should you get your first bone density scan?
All women should have a bone density scan by the age of 65, but women who have risk factors should be tested sooner. The bone density often decreases after menopause with the loss of estrogen, which is protective for the bones. If a women is at increased risk of osteoporosis, obtaining a DXA scan at menopause can serve as a baseline.
The frequency of testing depends on the results of the previous scan, and whether medication for osteoporosis is being administered, or if there are changes in medical history. Often, when a person is being monitored for low bone density, the test is repeated about every two years. If a person has a very good DXA scan, it might not be repeated for 5 years or more. If a women has a significant fracture, the bone density should be evaluated. In certain cases, the bone density may be evaluated after one year, if a certain intervention is being monitored.
What is a DXA scan?
A DXA scan, dual-energy X-ray absorptiometry of the lumbar spine and hip is the most commonly used test to evaluate bone density. Studies that evaluate the heel and wrist are predictive, but are not sufficient to monitor treatment effects.
The test is done by a trained technician. The patient lies on a table and the scanner passes over the lumber spine and hip after the patient is properly positioned. The amount of radiation of the x-ray is very low. The beams of the scanner are able to evaluate the density of the bone. The test is painless. Often, a vertebral fracture assessment is obtained. By lying on your side, the vertebrae are measured to see if there is any compression or fracture.
How do you evaluate the results?
After the test is completed, the technician will evaluate the scans that are obtained. A calculation, or T-score is obtained. The T-score compares your bone density to the bone density of a 30 year old women. The T-score is reported in standard deviations from the mean.
There are 3 possible results:
T-score: > -1.0 Normal bone density
T-score: > -1.0 to -2.5 Osteopenia ( low bone density but not osteoporosis)
T-score: <-2.5 Osteoporosis
The diagnosis of osteoporosis can be made without a bone density test. A history of a low-trauma fracture in a woman at risk would suffice for the diagnosis of osteoporosis. An example would be a vertebral fracture that resulted from a fall from the standing position vs. falling off a ladder. In most cases, women who have surgery for a broken hip should be treated for osteoporosis.
What is a FRAX Score?
A FRAX score is an assessment tool used to predict the risk of fracture in the next ten years.
The clinical risk factors that are part of the calculation include your age, sex, body mass index, previous fragility fracture, parental hip fracture, current smoking history, use of steroids (more than the equivalent of 5 mg of prednisolone per day for 3 months), alcohol use of more than 3 drinks per day, or other secondary causes of osteoporosis. Results are specific for race and gender. This tool is used to assess those with osteopenia, to determine if other factors increase the fracture risk and to determine if treatment is appropriate.
Generally, if you DXA scan falls into the osteoporosis range, medication is indicated.
If a patient has osteopenia, and her FRAX risk in greater than 20% risk of a major osteoporotic fracture in the next ten years, or a 3% risk of a hip fracture in the next 10 years, medication should be considered.
In the next edition of this series, we will look at treatments for osteoporosis: the pros and cons of medication therapy.
Marilyn Jerome, MD
Foxhall OB-Gyn Associates
The American College of Obstetricians and Gynecologists. Practice Bulletin. Number 129. September 2012. Osteoporosis
It's not too late to exercise: benefits for the heart (and a look at high-intensity interval training)
A study published in the Journal, Circulation, in January 2018, demonstrated that increasing your exercise routine in mid-life can improve your heart function and reverse some of the effects of aging. Poor fitness in middle-age is a risk factor for heart failure.
The study looked at 61 adults, aged 45 to 64, who were healthy but who lived a sedentary life style. The researchers divided up the group in two. In the control group, the participants were asked to do yoga, balance exercises, and strength training three times per week. The study group was given a moderate exercise plan, which was ramped up as the study continued. They were given high-intensity interval training as part of the routine. After six months, the exercise group was up to 5-6 hours of exercise per week. At least two days involved high-intensity interval training.
So, let’s define high-intensity interval training (HIIT) and its benefits. HIIT is defined as alternating hard-charging intervals of exercise which increases the heart rate to 80% of
its maximum capacity for usually 1-5 minutes, with periods of rest or less intense exercise.
To determine your maximum heart rate, you can use this formula: 220 minus your age.
Then, your target heart rate for exercise is 50-85% of that.
So for example, if you are 66 years old, your maximum heart rate would be 220-66=154.
50-85% of that is a heart rate of 77-131. 80% of 154 is 123. During the high intensity intervals you would want to get your heart rate up to 123. ALWAYS, BEFORE YOU START AN INTENSE EXERCISE REGIME, MAKE SURE YOUR DOCTOR ASSERTS THAT YOUR HEART IS IN GOOD SHAPE. YOU MIGHT NEED A CARDIAC EVALUATION IF YOUR ARE OLDER OR HAVE RISK FACTORS.
An example of a HIIT routine if you were a runner would be a 10 minute warm up, followed by 4 intervals of 4 minutes of fast running interspersed with 3 minutes of brisk walking, followed at the end by a 5 minute cool down.
Another example would be alternating 1 minute of high intensity exercise with one minute of less intense exercise, for a total of 20 minutes. This could be done walking, on a treadmill, bike, elliptical, or almost any other type of exercise amenable to changing intensity.
Scientists that have studied this type of training have found cardiac benefits. VO2 max is a measure of the maximum volume of oxygen that your body uses during intense activity during a specific amount of time. It is one of the best predictors of overall
health. If you are more aerobically fit, your heart pumps better and it takes longer for you to tire and become breathless. Studies have shown similar increases in VO2
max in comparing groups that exercised at 50 minutes versus those who exercised only
for 10 minutes with high-intensity intervals that added up to 1 minute total. Wow!
Same cardiac benefit for 20% of the time. Nice!
A study done by Martin Gabala at McMaster University in Canada, a leading expert in HIIT, demonstrated that obese sedentary adults that exercise three times per week for a total of only 30 minutes, about 10 minutes each time, with 3, 20 second high-intensity intervals, improved their VO2 max. It did not take much to improve cardiac function.
Studies that compared different types of interval training determined that longer high-intensity intervals had greater benefit, which would be expected. To get the maximum benefit, 4-5 intervals lasting 3-5 minutes were required.
Besides increased VO2 max, HIIT increased stroke volume in the heart, which is the amount of blood ejected with each heart beat. Calorie consumption with HIIT of 20 minutes is comparable to an endurance exercise of 50 minutes, but the effect on weight loss is less impressive. There is not enough data to suggest that HIIT is a more effective way to lose weight. In general, caloric restriction is far more effective way to lose weight than exercise. Studies have shown that the amount of weight loss is less than expected for the number of calories expended during exercise. But don’t despair, there are still many health benefits of exercise. ,
Of those who completed the study, about 86%, cardiac changes were noted that included increased fitness measured by oxygen consumption, and increased cardiac contractility or stretchiness, which increased the hearts ability to pump blood.
The authors of the study recommended starting an exercise regime sooner than later, before you develop joint problems or other health issues that can affect your ability to exercise. However, at any age, beginning an exercise routine can reduce the risk of heart disease, and help manage blood pressure and blood sugar. The benefits to your bones and preventing falls that can lead to fractures are also an important benefit.
In summary, beginning exercise at any age can have cardiac benefits, just make sure your heart can handle it. If you up the ante by doing high-intensity interval training you will get a similar cardiac benefit in less time. The longer the intervals you can sustain provide more substantial are the benefits. The bottom line, it is never too late to begin exercising!
Harvard Women’s Health Watch, Volume 26. Number 5, January 2019.
Regular exercise helps reverse age-related changes in your heart.
Circulation. Volume 137, Issue 15. April 10, 2018.
Randomized Control Trial: Implications for Heart Failure Prevention
Vox. How to get the most out of your exercise time, according to science, by Julia Belluz,
updated January 13, 2019.