Osteoporosis is an important health problem affecting mature and menopausal women. There are an estimated 28 million Americans affected by this crippling disease not to mention the probably hundreds of millions in the rest of the world. 80% of the 28 million Americans are women. Approximately 1.3 to 1.5 million fractures will occur in the United States. Hip fracture, a serious manifestation of osteoporosis, accounts for about 15% of the total. Hip fractures are devastating to older women because 20% of victims will die, 25% of the survivors will be confined to nursing homes, and 50% will suffer significant alterations to their life style. The other most common fracture is a vertebral (spinal) fracture.

What is Osteoporosis?

Osteoporosis is thinning of the bones. To be diagnosed with osteoporosis, a person must have a bone mineral density of approximately 2.5 standard deviations or more below mean of a young adult. Osteopenia which means low bone mineral density is defined as 1 to 2.5 standard deviations below the mean.

How does bone renew itself and how does Osteoporosis develop?

Bone is constantly being remodeled in order to provide optimal support and to repair damage occurring from daily activities. This is done mainly by two types of bone cells. Bone density declines if there is too much bone removed or if not enough is laid down. Bone matrix is constantly being formed and removed at an equal rate in young adults who have adequate nutrition and exercise. Peak bone mass is achieved at age 30 in both men and women.

After reaching peak bone mass, about 0.4% of bone is lost per year in both sexes. Bone loss accelerates in women just after menopause to 2% of cortical bone (hard outer surface of the bone) and 5% of trabecular bone (spongy internal bone) for the first 5 to 8 years following menopause. With aging, the coordinated balance between the two types of bone cells is disrupted and results in a net bone loss.

Who is at most risk for this condition?

Women tend to be more at risk for this condition because they have less bone mass to start with.

Lack of estrogen during the menopausal years only accelerates this condition. There are variations among races. White and Asian women have the greatest risk. African American are at lowest risk. Hispanic women are somewhere in between. The racial differences are due, in part, to genetic determinates of body size, body composition, and bone metabolism. Osteoporosis runs in families. These factors are considered non-modifiable.

However, many lifestyle modifications can reduce and advert one from becoming osteoportic. Cigarette smoking (causes an early menopause), heavy alcohol consumption, and high caffeine intake can cause decreased bone mass. Dietary calcium intake has an important part in maintaining a good bone matrix. The amount of calcium the intestines can absorb is reduced in older patients. Diets adequate in vitamin D and its metabolites are essential to calcium metabolism and maintenance of mineral balance. High protein diets may cause the body to dump calcium over the short term, but over a longer period it is not responsible for osteoporosis.

Are there tests for Osteoporosis?

There are many recommendations for screening of osteoporosis; however, there is no one single standard. Bone mass measurement is recommended for people at risk for this disease. Someone who is menopausal and cannot take estrogen is someone who should undergo screening. There are a number of bone mineral density tests that can be done:

1. Dual-energy x-ray absorptiometry (DXA) - measures BMD (bone mineral density) in the spine, hip, and wrist in a few minutes, with one-tenth the radiation of a standard chest x-ray.

2. Single-energy x-ray absorptionmetry (SXA)- measures BMD in wrist and heel.

3. Ultrasound densitometry: assesses bone in the heel, lower leg, and knee.

4. Radiographic absorptionmetry: measures bones in the hand.

5. Quantitative computed tomography : measures BMD in spine

A simple measurement of height can establish a presumptive diagnosis of Osteoporosis. If a patient has lost more than 1 inch in height from her maximal adult height, this is good clinical evidence of osteoporosis. There are measurable chemicals in the blood and urine which can signify bone loss.

How is it treated and/or prevented?

Estrogens (Estrace, Estraderm, Estratab, Ogen, Menest, Premarin) - Are first line agents in the treatment and prevention of osteoporosis. Studies show up to a 60% decrease in spinal fractures and a 25% decrease in other fractures with 5 years of estrogen replacement therapy. Some studies say a 50% reduction in the incidence of hip fracture. This therapy is not be suitable for women who have had breast cancer, uterine cancer, undiagnosed bleeding, history of an active blood clot, stroke, or liver disease. Progesterone is added for women who have a uterus because of the slight increased risk of developing uterine cancer on estrogen alone.

Alendronate sodium (Fosamax). In postmenopausal women with osteoporosis, this drug slows the bone loss and increases BMD in both the spine and the hip. Approx. 48% in reduction of vertebral fractures is documented. Alendronate can be taken by women who have a either a contraindication to estrogen or do not want to take estrogen. This will not relieve hot flashes or other symptoms which are caused by a deficiency in estrogen.

Calcitonin (injectable: Calcimar, Miacalcin: intra nasal: Micacalcin Nasal Spray) A naturally occurring hormone that is secreted by the thyroid gland. Currently, the most convenient route of administration of calcitonin is by nasal spray. The nasal spray has been demonstrated in certain studies to reduce the risk of spinal fracture by 36% to 45%. This is used for the treatment of osteoporosis.

Raloxifene (Evista) This is called a synthetic estrogen. A SREM (selective receptor estrogen modulator) which will only stimulate estrogen receptor sites such as the bone. It will beneficially alter the lipid profile as well. This compound will not stimulate the breast or the lining of the uterus, and can be used on people with a contraindication to estrogen use.

Its current indication is prevention.

How can osteoporosis be managed?

After getting your test results, you may discuss with your doctor a lifestyle plan to prevent the disease or further progression. Weight-bearing exercise stimulates bone cells to lay down new bone. A diet with adequate calcium is important in the prevention of osteoporosis.

Your doctor may also test your urine to determine how quickly you are losing bone. A second urine test can be done 3 months later to see whether the medication is working. One to three years later after your diagnosis, your doctor will perform another BMD test to re-evaluate your condition.

What are some things I can do now to prevent this?

Consuming 1200 mg to 1500 mg of Calcium a day. Calcium is found in dairy products, dark-green leafy vegetables, tofu (has weak estrogen too), almonds, salmon, and sardine with bones.

Weight bearing exercise for 20 minutes, 3 times daily can help. Walking, jogging, stair climbing, and tennis can help as well. Don't forget to get a follow-up BMD test in one to three years to see if the treatment plan is working.

^* Please see the article What Is Menopause? for reference and more detailed information.

Ryan K. Lee is a physician specializing in Obstetrics and Gynecology. He is currently in private practice in Glendale and Los Angeles, California.