More than 25
million Americans have gallstones, and a million are diagnosed each
year. However, only 1 - 3% of the population complains of symptoms
during the course of a year, and fewer than half of these people
have symptoms that return.
Risk Factors in
Women
Women are much
more likely than men to develop gallstones. Gallstones occur in
nearly 25% of women in the U.S. by age 60, and as many as 50% by age
75. In most cases, they have no symptoms. In general, women are
probably at increased risk because estrogen stimulates the liver to
remove more cholesterol from blood and divert it into the bile.
Pregnancy.
Pregnancy increases the risk for gallstones, and pregnant women with
stones are more likely to have symptoms than nonpregnant women.
Surgery should be delayed until after delivery if possible. In fact,
gallstones may disappear after delivery. If surgery is necessary,
laparoscopy is the safest approach.
Hormone
Replacement Therapy. Several large studies have shown that the use
of hormone replacement therapy (HRT) doubles or triples the risk for
gallstones, hospitalization for gallbladder disease, or gallbladder
surgery. Estrogen raises triglycerides, a fatty acid that increases
the risk for cholesterol stones. How the hormones are delivered may
make a difference, however. Women who use a patch or gel form of HRT
face less risk than those who take a pill. HRT may also be a
less-than-attractive option for women because studies have shown it
has negative effects on the heart and increases the risk for breast
cancer.
Risk Factors in
Men
About 20% of men
have gallstones by the time they reach age 75. Because most cases do
not have symptoms, however, the rates may be underestimated in
elderly men. One study of nursing home residents reported that 66%
of the women and 51% of the men had gallstones. Men who have their
gallbladder removed are more likely to have severe disease and
surgical complications than women.
Risks in
Children
Gallstone
disease is relatively rare in children. When gallstones do occur in
this age group, they are more likely to be pigment stones. Girls do
not seem to be more at risk than boys.
The following
conditions may put children at higher risk:
• Spinal injury
• History of abdominal surgery
• Sickle-cell anemia
• Impaired immune system
• Receiving nutrition through a vein (intravenous)
Ethnicity
Because
gallstones are related to diet, particularly fat intake, the
incidence of gallstones varies widely among nations and regions. For
example, Hispanics and Northern Europeans have a higher risk for
gallstones than do people of Asian and African descent. People of
Asian descent who develop gallstones are most likely to have the
brown pigment type.
Native North and
South Americans, such as Pima Indians in the U.S. and native
populations in Chile and Peru, are especially prone to developing
gallstones. Pima women have an 80% chance of developing gallstones
during their lives, and virtually all native Indian females in Chile
and Peru develop gallstones. Such cases are most likely due to a
combination of genetic and dietary factors.
UK, London,
Sydney, Australia
Mount Isa, Queensland,
Bahamas, Nassau
Benalla, Victoria,
Chile, Santiago
Armenia, Yerevan
Ukraine, Kiev
Fort Wayne, Indiana, USA
Port Augusta, South Australia