Background
Gout is a very common cause of inflammatory arthritis (pain, redness, warmth and swelling of affected joints) and is caused by urate crystals forming either within or around joints. Uric acid is a normal waste product that is usually excreted with urine. However, in the case of gout, there is either excessive production of uric acid, or the body is not able to excrete it quickly enough, or a combination of both. An attack of gout usually occurs rapidly and usually resolves within 7 to 10 days.
Colchicine is a drug that is used mainly in gout to treat an acute attack or to prevent an attack while starting uric acid-lowering therapy.
Study characteristics
This Cochrane Review is current to August 2020. We included four trials (803 randomised participants) in this updated review, including two new trials. One three-arm trial compared high-dose colchicine (52 participants), low-dose colchicine (74 participants) and placebo (fake medicine) (59 participants); one trial compared high-dose colchicine with placebo (43 participants); one trial compared low-dose colchicine with non-steroidal anti-inflammatory drugs (NSAIDs) (399 participants); and one trial compared low-dose colchicine with Chuanhu anti-gout mixture (traditional Chinese Medicine compound) (176 participants). We selected low-dose colchicine compared with placebo as the primary comparison; the low dose is consistent with doses used in practice. Trials were performed in hospital and multicentre settings in four countries, the majority of participants were male, and mean age ranged between 51.2 and 70 years. One trial received funding from a pharmaceutical company that was involved in the study design, data collection, data analysis, and manuscript writing.
Key results
Compared with placebo medication, low-dose colchicine for people with acute gout may slightly improve treatment outcomes with little or no increased risk of adverse events at 32 to 36 hours.
Proportion of participants reporting treatment success (defined as 50% or more reduction in pain)
25% more people (7% more to 42% more) reported success, or 25 more out of 100
- 42 people out of 100 reported treatment success with colchicine
- 17 people out of 100 reported treatment success with placebo
Total adverse events (diarrhoea, vomiting or nausea)
6% more people reported adverse events (13% more to 23% more), or 6 more out of 100
- 26 people out of 100 reported side effects with colchicine
- 20 people out of 100 reported side effects with placebo
Pain, reduction of inflammation, function of target joint, serious adverse events or withdrawals due to adverse events were not reported for this comparison.
Other comparisons are briefly summarised here:
High-dose colchicine may improve symptoms compared with placebo, but with more adverse events. High-dose may have little or no benefit over low-dose colchicine but more adverse events. There may also be little or no benefit of low-dose colchicine over NSAIDs in terms of treatment success and pain reduction, with a similar number of adverse events.
There were no trials that compared colchicine to glucocorticoids.
Quality of the evidence
We found low-quality evidence that low-dose colchicine may be an effective treatment for acute gout when compared to placebo and low-quality evidence that its benefits may be similar to NSAIDs. We downgraded the evidence for bias and imprecision. While both high- and low-dose colchicine improve treatment success when compared to placebo, high-dose (but not low-dose) colchicine may increase the number of adverse events compared to placebo while the number of adverse events may be similar with low-dose colchicine compared with NSAIDs.
Further research is very likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
We found low-quality evidence that low-dose colchicine may be an effective treatment for acute gout when compared to placebo and low-quality evidence that its benefits may be similar to NSAIDs. We downgraded the evidence for bias and imprecision. While both high- and low-dose colchicine improve pain when compared to placebo, low-quality evidence suggests that high-dose (but not low-dose) colchicine may increase the number of adverse events compared to placebo, while low-quality evidence indicates that the number of adverse events may be similar with low-dose colchicine and NSAIDs.
Further trials comparing colchicine to placebo or other treatment will likely have an important impact on our confidence in the effect estimates and may change the conclusions of this review. There are no trials reporting the effect of colchicine in populations with comorbidities or in comparison with other commonly used treatments, such as glucocorticoids.
This is an updated Cochrane Review, first published in 2006 and updated in 2014. Gout is one of the most common rheumatic diseases worldwide. Despite the use of colchicine as one of the first-line therapies for the treatment of acute gout, evidence for its benefits and harms is relatively limited.
To update the available evidence of the benefits and harms of colchicine for the treatment of acute gout.
We updated the search of CENTRAL, MEDLINE, Embase, Clinicaltrials.gov and WHO ICTRP registries to 28 August 2020. We did not impose any date or language restrictions in the search.
We considered published randomised controlled trials (RCTs) and quasi-randomised controlled trials (quasi-RCTs) evaluating colchicine therapy compared with another therapy (placebo or active) in acute gout; low-dose colchicine at clinically relevant doses compared with placebo was the primary comparison. The major outcomes were pain, participant global assessment of treatment success (proportion with 50% or greater decrease in pain from baseline up to 32 to 36 hours), reduction of inflammation, function of target joint, serious adverse events, total adverse events and withdrawals due to adverse events.
We used standard methodological procedures as expected by Cochrane in this review update.
We included four trials (803 randomised participants), including two new trials, in this updated review. One three-arm trial compared high-dose colchicine (52 participants), low-dose colchicine (74 participants) and placebo (59 participants); one trial compared high-dose colchicine with placebo (43 participants); one trial compared low-dose colchicine with non-steroidal anti-inflammatory drugs (NSAIDs) (399 participants); and one trial compared low-dose colchicine with Chuanhu anti-gout mixture (traditional Chinese Medicine compound) (176 participants). We did not identify any trials comparing colchicine to glucocorticoids (by any route).
The mean age of participants ranged from 51.2 to 70 years, and trial duration from 48 hours to 12 weeks. Two trials were at low risk of bias, one was possibly susceptible to selection bias (random sequence generation), reporting bias and other bias, and one open-label trial was at high risk of performance and detection bias.
For the primary comparison, low-quality evidence from one trial (103 participants, downgraded for imprecision and bias) suggests low-dose colchicine may improve treatment outcome compared to placebo with little or no increased risk of adverse events. The number of people who reported treatment success (50% or greater pain reduction) at 32 to 36 hours was slightly larger with low-dose colchicine (418 per 1000) compared with placebo (172 per 1000; risk ratio (RR) 2.43, 95% confidence interval (CI) 1.05 to 5.64; absolute improvement 25% more reported success (7% more to 42% more, the 95% CIs include both a clinically important and unimportant benefit); relative change of 143% more people reported treatment success (5% more to 464% more). The incidence of total adverse events was 364 per 1000 with low-dose colchicine compared with 276 per 1000 with placebo: RR 1.32, 95% CI 0.68 to 2.56; absolute difference 9% more events with low-dose colchicine (9% fewer to 43% more, the 95% CIs include both a clinically important effect and no effect); relative change of 32% more events (32% fewer to 156% more). No participants withdrew due to adverse events or reported any serious adverse events. Pain, inflammation and function were not reported.
Low-quality evidence (downgraded for imprecision and bias) from two trials (124 participants) suggests that high-dose colchicine compared to placebo may improve symptoms, but with increased risk of harms. More participants reported treatment success at 32 to 36 hours with high-dose colchicine (518 per 1000) compared with placebo (240 per 1000): RR 2.16, 95% CI 1.28 to 3.65, absolute improvement 28% (8% more to 46% more); more also had reduced inflammation at this time point with high-dose colchicine (504 per 1000) compared with placebo (48 per 1000): RR 10.50, 95% CI 1.48 to 74.38; absolute improvement 45% greater (22% greater to 68% greater); but more adverse events were reported with high-dose colchicine (829 per 1000 compared with 260 per 1000): RR 3.21, 95% CI 2.01 to 5.11, absolute difference 57% (26% more to 74% more). Pain and function were not reported.
Low-quality evidence from a single trial comparing high-dose to low-dose colchicine indicates there may be little or no difference in benefit in terms of treatment success at 32 to 36 hours but more adverse events associated with the higher dose. Similarly, low-quality evidence from a single trial indicates there may also be little or no benefit of low-dose colchicine over NSAIDs in terms of treatment success and pain reduction at seven days, with a similar number of adverse events reported at four weeks follow-up. Reduction of inflammation, function of target joint and withdrawals due to adverse events were not reported in either of these trials, and pain was not reported in the high-dose versus low-dose colchicine trial.
We were unable to estimate the risk of serious adverse events for most comparisons as there were few events reported in the trials. One trial (399 participants) reported three serious adverse (one in a participant receiving low-dose colchicine and two in participants receiving NSAIDs), due to reasons unrelated to the trial (low-quality evidence downgraded for bias and imprecision).