What causes gout?
Poor dietary habits, lack of exercise, obesity or overweight and metabolic syndromes (high blood pressure, diabetes, high cholesterol) and genetics can all cause gout. High body mass index (weight in kilograms divided by the square of height in metres), waist-to-hip ratio and weight gain have all been associated with the risk of gout in men. Obesity and insulin resistance syndrome (which increases the risk of diabetes) are both associated with hyperuricaemia. The role of genetics is also becoming more evident.
Gout can develop over many years and in different stages:
- Acute gout;
- Chronic gout.
How does gout develop?
Gout develops as a consequence of increased uric acid levels (hyperuricaemia) in the blood and progresses over many years.
The disease is currently described in four different stages:
Stage I: asymptomatic hyperuricaemia
Gout usually begins as asymptomatic hyperuricaemia – this is when uric acid levels are slightly elevated but do not usually cause any symptoms until several years later. Patients are seldom diagnosed at this stage. Although hyperuricaemia does not usually cause symptoms, the raised uric acid levels can have a negative impact on the kidneys and the heart and vessels. Gout is generally diagnosed when a patient has a gout attack or develops kidney disease.
Stage II: acute gout attack
The first acute gout attack often occurs without warning. These attacks of severe pain usually happen at night or early in the morning. The affected joint is typically extremely sensitive to touch or move, swollen, hot and red or blue in colour. The attack is also commonly accompanied by fever. Without treatment, these symptoms may last for several hours or even days. If the disease remains untreated, these attacks may take place at increasingly shorter intervals, lasting longer and spreading to other joints.
Stage III: periods without symptoms between two recurrent attacks of gout
Without treatment, gout attacks re-occur at irregular intervals. Although there are no signs of the disease between attacks, uric acid levels remain elevated.
Stage IV: chronic gout
Chronic gout is a multisystemic disease, which means it affects many parts of the body and should therefore be taken seriously. When gout becomes chronic, it damages the joints and soft tissues as well as the kidneys and other organs like the heart or intestines. ’Men with gout have an increased risk (1.21 times) of erectile dysfunction. Gout is a chronic progressive disease – this means that it usually gets worse over time and therefore requires long-term treatment and regular monitoring of uric acid levels. After an acute gout attack, patients enter into what is called a "remission phase"; there are no symptoms in this period. It may be suddenly interrupted by new attacks if proper treatment for hyperuricaemia has not been introduced. The remission phase can be long after the first attack. Without proper treatment, however, attacks become more frequent and more severe.
Uric acid crystals are commonly deposited in the kidneys, further obstructing the outflow of uric acid and leading to the formation of kidney stones. This makes the urine even more acidic, which in turn can lead to the increased formation of kidney stones. Every deposit of uric acid crystals presents a risk to the joints due to the inflammation it can cause.
If gout is not treated properly,
the formation of tophi can cause changes in the joint and ultimately lead to its destruction.
Feet and hands are the most affected regions, followed by the elbows and knees; this results in significant reductions to the patient's mobility. The affected bones and joints are also more likely to break .
Many studies have shown that an elevated uric acid level may have long-term effects on the blood vessels and subsequently increase the risk of cardiovascular disease. Cardiovascular damage also appears to be responsible for elevated uric acid levels associated with high blood pressure. Patients with gout frequently also have high blood pressure, partially because both diseases can be a result of chronic kidney failure.