Uric acid has dropped, but the "storm" is coming back?

Author: Li Jiecheng Peking University People's Hospital

Reviewer: Li Wenhai, Chief Physician, Peking University People's Hospital

Many people believe that once the blood uric acid level of a gout patient is lowered, gout will not attack. However, this is not the case. Although lowering blood uric acid can reduce the risk of gout attacks, it is not uncommon for gout to recur during uric acid-lowering treatment. Why is this? Many gout patients and hyperuricemia patients are puzzled by this. Let's start from the beginning and answer your questions!

1. Gout and blood uric acid

In the past 30 years, the prevalence of hyperuricemia and gout in my country has increased dramatically, and there is a clear trend of younger patients. Hyperuricemia and gout are risk factors for diseases such as chronic kidney disease, hypertension, cerebrovascular disease and diabetes, and are predictors of premature death. Frequent attacks of gout can lead to the deposition of urate crystals and form tophi. The damage of tophi to the joints, the difficult-to-heal skin sinuses formed by the rupture of tophi, and the compression of deep tophi on the nerves all seriously affect the quality of life of gout patients.

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2. Lowering uric acid is the key to treating gout

Hyperuricemia is the prerequisite and cause of gout. Therefore, controlling blood uric acid levels is the fundamental to controlling gout attacks, and uric acid-lowering treatment is the key to curing gout.

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3. Fluctuations in blood uric acid levels in patients with chronic hyperuricemia can trigger gout attacks

Uric acid is a marker for a series of metabolic and hemodynamic abnormalities, but high blood uric acid levels do not mean gout. Hyperuricemia is one of the important risk factors for gout attacks. Chronic hyperuricemia is the basis and prerequisite for gout attacks. On this basis, the fluctuation of blood uric acid levels leads to the exposure of urate crystals in the tissues around the joints, which is the cause of gout attacks.

In daily life, although the blood uric acid level of gout patients is usually higher than that of healthy people, the free blood uric acid in the patient's blood and tissue fluid and the urate crystals deposited in the joints and surrounding soft tissues are actually in a relatively stable state. When using uric acid-lowering drugs, if the uric acid level is lowered "too harshly", this dynamic balance will be broken. At this time, the blood uric acid in the synovial fluid and tissue fluid of the joints will also decrease, causing the surface of the urate crystals attached to the joints to dissolve. However, when the urate crystals dissolve, a large number of needle-shaped urate crystals are released. These crystals stimulate the body to produce an immune response, thereby triggering a secondary attack of gouty arthritis. This situation is the repeated attacks of gout caused by the rapid decrease of uric acid, which is called "crystal dissolution pain" and is a common phenomenon in gout patients during the process of lowering uric acid.

Specific measures to reduce gout attacks during uric acid-lowering treatment

1. The initial treatment of uric acid-lowering drugs should be slow rather than fast, and the drug dosage should be small rather than large. For example, starting from the minimum dose, allopurinol 50mg, febuxostat 20mg, benzbromarone 50mg, test the blood uric acid level once every 2 to 5 weeks, and slowly increase the drug dosage according to the degree of decrease in blood uric acid. The selection and dosage of uric acid-lowering drugs must also be combined with the results of liver and kidney function tests, and then decided by the doctor after evaluation. Do not stop, change or increase the dosage without authorization.

2. Use preventive drugs at the same time in the early stage of uric acid-lowering treatment to further reduce the frequency of gout attacks. Preventive medication mainly consists of 0.5-1.0 mg of colchicine per day, and small doses of non-steroidal anti-inflammatory drugs can also be used. Related anti-inflammatory and analgesic drugs for preventive use need to be used for 3-6 months. The specific time can be determined according to the dissolution of urate crystals, and the time to stop the drug can be within this period.

3. Use drugs that affect blood uric acid levels with caution, such as cyclosporine, aspirin, etc. Patients with morning urine pH <5 or combined uric acid kidney stones should take appropriate drugs to alkalinize urine while lowering uric acid, and monitor urine pH regularly to reduce the incidence of kidney stones.

4. Changing your lifestyle is a simple, easy and effective measure to reduce gout attacks. In the first 3 to 6 months of lowering uric acid, patients with hyperuricemia and gout should pay attention to keeping their joints warm, especially the feet, ankles, knees and hands, which are prone to gout. This is an effective measure to reduce and prevent gout attacks. Drinking a lot of alcohol in a short period of time, overindulging in high-purine foods, losing weight quickly, and dehydration after exercise often lead to a rapid increase in blood urate levels, triggering gout attacks. Therefore, a good lifestyle may be the best way to avoid hyperuricemia and gout.

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