There are four types of
osteoporosis: primary, secondary, osteogenesis
imperfecta, and idiopathic juvenile.
Primary osteoporosis
Primary osteoporosis is the most common type of osteoporosis. It is
more common in women than men. A person reaches peak bone mass (density) at
about age 30; after that, the rate of bone loss slowly increases, while the
rate of bone building decreases. Whether a person develops osteoporosis depends
on the thickness of the bones in early life, as well as health, diet, and
physical activity at all ages.
In women, accelerated bone loss usually begins after monthly
menstrual periods stop, when a woman's production of estrogen slows down
(usually between the ages of 45 and 55). In men, gradual bone thinning
typically starts at about 45 to 50 years of age, when a man's production of
testosterone slows down. Osteoporosis usually does not have an effect on people
until they are 60 or older. Women are usually affected at an earlier age than
men, because they start out with lower bone mass.
Secondary osteoporosis
Secondary osteoporosis has the same symptoms as primary
osteoporosis. However, it occurs as a result of having certain medical
conditions, such as
hyperthyroidism or
leukemia. It may also occur as a result of taking
medications known to cause bone breakdown, such as oral or high-dose inhaled
corticosteroids (if used for more than 6 months), too high a dose of thyroid
replacement, or aromatase inhibitors (used to treat breast cancer). Secondary
osteoporosis can occur at any age.
Osteogenesis imperfecta
Osteogenesis imperfecta is a rare form of osteoporosis that is
present at birth. Osteogenesis imperfecta causes bones to break for no apparent
reason.
Idiopathic juvenile osteoporosis
Idiopathic juvenile osteoporosis is rare. It occurs in children
between the ages of 8 and 14 or during times of rapid growth. There is no known
cause for this type of osteoporosis, in which there is too little bone
formation or excessive bone loss. This condition increases the risk of
fractures.