a. The World Health Organization has established
diagnostic criteria for osteoporosis based on bone
density measurements.
b. Osteoporosis is defined as a bone mineral density
greater than 2.5 SD below the mean BMD of a
young adult woman at her peak bone mass (T-score).
c. Osteopenia is defined as a BMD between 1 and 2.5
SD below the mean.
d. A BMD within 1 SD of the mean is considered
normal.- There is some controversy about whether these crite-
ria are appropriate to use when evaluating adolescents
and young women with low bone mass secondary as
part of the female athlete triad, as the criteria were
established to be used when evaluating post-
menopausal women. - The female athlete triad leads to decreased BMD
because bone growth and development is dependent
on mechanical, nutritional, and hormonal influences.
Women and girls with an energy deficit resulting from
decreased caloric intake are at risk of having
decreased BMD. Studies have also found a linear rela-
tionship between the degree of menstrual dysfunction
and vertebral bone density (Vuori and Heinonen,
2000). - The standard method of diagnosing osteoporosis is by
dual X-ray absorptiometry(DEXA), which is used to
measure bone density at various places, usually the
hip, spine, and distal radius. These measurements are
used to generate the above mentioned T-score, and an
age-matched Z-score. - It’s estimated that 30 million women in the United
States have osteoporosis and the estimated direct med-
ical costs for treating osteoporosis are $16 billion annu-
ally (National Osteoporosis Foundation, America’s
Bone Health, 2002). - The U.S. Preventive Services Task Force recommends
BMD screening by DEXA for women over age 65, or
over age 60 for women identified as being high risk
for developing osteoporosis (US Preventive Services
Task Force, Recommendations and Rationale, 2002). - Nonmodifiable risk factors for osteoporosis (Lane,
2002):
a. Age
b. Sex
c. Race
d. Family history of osteoporosis
e. Past history of low-trauma fracture - Modifiable risk factors for osteoporosis (Lane, 2002).
a. Low body weight
b. Low calcium intake
c. Tobacco use
d. Excessive alcohol use
e. Lack of weightbearing exercise
f.Low muscle mass
g. Estrogen deficiency (including history of oligomen-
orrhea, amenorrhea, and delayed menarche)- Nonpharmacologic measures used in the prevention
and treatment of osteoporosis include the following
(Becker et al, 1999; Lane, 2002; Cundy et al, 2002;
Meier, 1997; Bonjour et al, 1997):
a. Ensuring adequate caloric intake to meet energy
needs, and maintain regular menses if premeno-
pausal
b. Weightbearing exercise (although it has been shown
that weightbearing exercise cannot overcome the
bone loss associated with amenorrhea secondary to
inadequate caloric intake) (Klibanski et al, 1995;
Nattiv, Callahan, and Kelman-Sherstinsky, 2002)
c. Decreasing tobacco and alcohol use - Nutritional measures used in the prevention and treat-
ment of osteoporosis include the following:
a. Calcium intake of 1500 mg daily—divided into
three doses containing at least 500 mg of elemen-
tal calcium to ensure absorption.
b. Vitamin D 800 IU daily - Pharmacologic treatments for pre- and post-
menopausal osteoporosis include estrogen, bisphos-
phonates, selective estrogen receptor modulators
(SERMs), and calcitonin. These antiresorptive agents
are indicated for the prevention and treatment of post-
menopausal osteoporosis. - There are currently no pharmacologic treatments
approved by the FDA to treat premenopausal osteo-
porosis. - It is thought that the primary problem in the young
female athlete is decreased bone formation rather than
premature bone loss, so the antiresorptive treatments
may not address the problem of adolescent osteopenia/
osteoporosis. There is also the concern of possible ter-
atogenic effects if bisphosphonates are used in women
of child-bearing age. - Adequate nutrition and weightbearing exercise during
the adolescent years is important for achieving peak
bone mass. On average, 92% of the total body BMD
is attained by age 18, and 99% is attained by age 26. - Different sites appear to mature at different ages. Peak
bone mass appears to be complete by age 16 in the
femoral neck, while the bone mass in the lumbar spine
appears to increase into the third decade (Weaver et al,
2001). - While amenorrhea is associated with osteopenia,
using oral contraceptive pills to induce menses has not
been shown to increase bone mass in the absence of
improved nutrition and calcium intake. In fact, some
studies have shown that oral contraceptives may actu-
ally cause a further decrease in BMD in adolescent
athletes (Weaver et al, 2001).
578 SECTION 7 • SPECIAL POPULATIONS