Gout Disease Blog Tag

I love it when gout forum posts trigger new lines of research for me.

A recent discussion about uric acid and heart disease prompted me to take a look at current research. This also tied in with a little bit of reorganizing I am doing. An old post about lowering uric acid levels did not appear to have any relevance to heart disease, but one link led to another, and before I knew it, a whole host of other diseases seemed to connect with gout.

Interestingly, the link between many of these diseases is via new research into allopurinol. I will come back to that at a later date, but for a hint of what is involved, please see Do you have gout with another disease?

Lower Uric Acid

In an earlier post, I mentioned that Hershfield believed that lowering uric acid below 2mg/dL (0.12 mmol/L) would probably be safe ^[1]. On reviewing that report in more detail, I noticed that much of his evidence was based on other diseases. There are conditions where people have the opposite conditions to gout sufferers. I.e., they either cannot produce uric acid or they over-excrete it. The first case is because they do not produce xanthine oxidase, the second because they have genetic kidney defects that stop the kidney from reclaiming uric acid. In both these conditions, people have no known ill-effects with uric acid levels below 1mg/dL (0.6mmol/L)
See how allopurinol helps more than gout

Increased Uric Acid – Increased Death Risk

Heart Risks Associated With Increased Uric Acid

Current thinking is neatly encapsulated in last year’s review by Gagliardi and colleagues [1]. Uric acid: A marker of increased cardiovascular risk, starts by telling us that uric acid has been linked with heart disease since the 19th century. At that time, there was no easy way to lower uric acid, though we now have effective gout treatments to avoid risks of high uric acid.

Over one hundred years later, we have a wealth of uric acid research relating to heart and associated risks. So common, that the review refers to “classical association of gout, hypertension, obesity and cardiovascular disease” [my bold]. It points out that, in addition to the well-known relationship between uric acid and deficiencies in purine metabolism, “increased uric acid is generally associated with important risk factors for atherosclerosis like hypertension, abdominal obesity, insulin resistance, the metabolic syndrome and renal failure.”

All these associations between uric acid and heart disease risks are reported in detail by Feig and colleagues [2].

More specifically, Car & Trkulja [3] have investigated uric acid levels in patients admitted to hospital with heart attacks. They have shown that increased uric acid is associated with increased risk of death in hospital, and death within 30 days. It is also associated with lower survival rates over five years following the heart attack.

Increased Uric Acid Conclusions

All these studies emphasize that whilst higher uric acid is associated with higher heart disease risks, nobody knows if there is any causal link. Neither do they show if heart disease problems are decreased if uric acid levels are decreased.

Although we do not know if increased uric acid might cause heart problems, or if undiagnosed heart problems cause high uric acid, several studies have shown that the risks are linked.

Increased Uric Acid Next Steps

If you have a personal or family history of high uric acid, it is important to see your doctor about your risks of heart disease.
Similarly if you have a personal or family history of heart disease, it is important to see your doctor about checking your uric acid level.

Leave Increased Uric Acid to browse the Gout Disease pages

Increased Uric Acid References

1. Authors: Gagliardi AC, Miname MH, Santos RD. Title: Uric acid: A marker of increased cardiovascular risk. Published: Atherosclerosis. 2009 Jan;202(1):11-7.
2. Authors: Daniel I. Feig, M.D., Ph.D., Duk-Hee Kang, M.D., and Richard J. Johnson, M.D. Title: Uric Acid and Cardiovascular Risk. Published: N Engl J Med. 2008 October 23; 359(17): 1811–1821. Uric Acid And Heart Risks
3. Authors: Car S, Trkulja V. Title: Higher serum uric acid on admission is associated with higher short-term mortality and poorer long-term survival after myocardial infarction: retrospective prognostic study. Published: Croat Med J. 2009 Dec;50(6):559-66. Uric Acid And Heart Attack Deaths

Though this new report[1] adds nothing to the Austrian study[2] in terms of understanding why elevated uric acid leads to kidney impairment, it does confirm that the two are linked. It certainly adds weight to my position that asymptomatic hyperuricemia should be taken much more seriously.
Learn more about High Uric Acid And Kidney Disease

Gout related research from Y P Siu and colleagues, Use of allopurinol in slowing the progression of renal disease through its ability to lower serum uric acid level,[1] investigates the use of allopurinol in patients with high uric acid levels and impaired kidney function.

They recognized that high uric acid levels (hyperuricemia) is associated strongly with the development of high blood pressure and kidney disease. As allopurinol decreases serum uric acid levels, they hypothesized that administrating allopurinol to decrease serum uric acid levels to the normal range in hyperuricemic patients with chronic kidney disease may be of benefit in decreasing blood pressure and slowing the rate of kidney disease progression.

They conducted a randomized controlled trial with 54 patients with high uric acid levels and chronic kidney disease. Half were treated with allopurinol tablets (100mg to 300mg per day), and half continued with normal treatment.

See the results of the Allopurinol Tablets & Kidney Disease study