Gout is caused by the precipitation of urate crystals in body tissues. It usually occurs in or around joints and results in a painful type of arthritis.
The urate crystals deposit in tissues when there is too much uric acid in the blood (hyperuricemia). Uric acid is a chemical that is created when the body breaks down purines in food. This condition can be caused by decreased excretion of uric acid, increased production of uric acid, or a high dietary intake of purine.
Decreased excretion of uric acid is the most common cause of gout. Uric acid is normally removed from your body by your kidneys. When this doesn’t happen efficiently, your uric acid level increases.
The cause may be hereditary, or you may have kidney problems that make you less able to remove uric acid. Lead poisoning and certain drugs, such as water pills (diuretics) and immunosuppressant drugs (e.g., cyclosporine), can cause kidney damage that may lead to uric acid retention. Uncontrolled diabetes and high blood pressure can also reduce kidney function.
Increased uric acid production can also cause gout. In most cases, the cause of increased uric acid production is not known. It can be caused by enzyme abnormalities and can happen in conditions including:
- hemolytic anemia
It may also occur as a side effect of chemotherapy or radiation therapy, because of a hereditary abnormality, or due to obesity.
A diet high in purines can lead to gout. Purines are natural chemical components of DNA and RNA. When your body breaks them down, they turn into uric acid. Some purines are found naturally in the body.
Some foods are especially high in purine and can raise uric acid levels in the blood. These high-purine foods include:
- organ meats, such as kidneys, liver, and sweetbreads
- red meat
- oily fish, such as sardines, anchovies, and herring
- certain vegetables, including asparagus and cauliflower
In many cases, the exact cause of gout or hyperuricemia is unknown. Doctors believe it may be due to a combination of hereditary, hormonal, or dietary factors. In some cases, drug therapy or certain medical conditions may also cause gout symptoms.
Age and gender
According to the Mayo Clinic, men are more likely than women to have symptoms of gout. Most men are diagnosed between 40 and 50 years of age. In women, the disease is most prevalent after menopause. Gout is rare in children and young adults.
People with blood relatives who have gout are more likely to be diagnosed with this condition themselves.
There are several medications that can increase your risk of gout. These include:
- daily low-dose aspirin, commonly used to prevent heart attack and stroke
- thiazide diuretics, used to treat high blood pressure, congestive heart failure, and other conditions
- immune suppression drugs, such as cyclosporine, taken after organ transplants and for some rheumatologic conditions
- levodopa, used to treat Parkinson’s disease
- niacin, used to increase high-density lipoproteins (HDL) in the blood
Moderate to heavy drinking increases the risk of gout. This usually means more than two drinks per day for men or one per day for women. Beer especially has been linked to gout attacks since it’s high in purines.
Exposure to high levels of lead is also associated with gout.
Other health conditions
People who suffer from the following diseases and conditions are more likely to have gout:
- high blood pressure
- high cholesterol
- hemolytic anemia
- kidney disease
Other things that may trigger a gout attack include:
- joint injury
- crash diets
- rapid lowering of uric acid levels through medication