Gout single map PHO analysis Consumer summary (133KB, pdf)

This Atlas domain presents information on gout by district health board (DHB) including prevalence, prevalence by ethnicity and treatment. It identifies areas of wide variation between DHBs and opportunities for quality improvement.

Updated 2020

This domain has been updated with data from 2012–18.

Key messages

  • Gout is estimated to affect around 5 percent of the total population aged 20 and over. People aged 65 and over, men, Māori and Pacific peoples are most affected. For those aged 20–44, the prevalence of identified gout for Māori and Pacific peoples is four and eight times that of non-Māori, non-Pacific populations. 
  • A new indicator reports any dispensing of urate-lowering therapy, in addition to the current indicator reporting regular dispensing of urate-lowering therapy. It shows that, while Māori and Pacific peoples were more likely to receive some urate-lowering therapy in a year, they were less likely to receive it regularly. The urate-lowering therapy benefits people when used continuously long-term. 
  • Māori and Pacific peoples with gout were dispensed more non-steroidal anti-inflammatory drugs (NSAIDs) than other ethnic groups. There is concern about the relationship of NSAID use and kidney damage. Kidney disease is more common in Māori and Pacific peoples, so more research and debate into the use of these drugs is needed. 
  • Māori and Pacific peoples of all ages were more likely to receive colchicine, prednisone or NSAIDs than other ethnic groups.
  • Māori and Pacific peoples had 5–10 times as many admissions due to gout than non-Māori, non-Pacific populations.

Key findings

The number and prevalence of people identified as having gout is increasing.[1] Men, Māori, Pacific peoples and people aged 65 and over are most affected.
  • In 2018 on average, 5.5 percent of the population aged 20 years and over were identified as having gout (199,000 people). This increased from 4.5 percent in 2012 (146,000 people).
  • Gout prevalence varied 2.4-fold between DHBs, ranging from 3.7 percent in Canterbury DHB to 9 percent in Hauora Tairāwhiti, likely reflecting different ethnicity and age structures between DHBs.
  • Gout prevalence increased significantly with age.
  • Men had over three times the gout prevalence of women.
  • Māori and Pacific peoples had 2-3 times the gout prevalence of non-Māori, non-Pacific populations. For those aged 20–44 years, the prevalence of identified gout for Māori and Pacific peoples is four and eight times that of non-Māori, non-Pacific populations. In men aged 65 and over, gout is estimated to affect 17 percent of those identifying as non-Māori, non-Pacific, 37 percent of Māori and 49 percent of Pacific peoples.

Table 1: Population identified as having gout, by age, ethnicity and gender, 2018

Ethnicity Age and gender
20–44 years 45–64 years 65+ years All age groups
Female Male Female Male Female Male Female Male
Māori 0.9 5.8 5.3 20.1 18.9 37.3 4.4 13.8
Pacific peoples 1.8 12.3 9.2 34.0 25.9 48.6 6.7 22.5
Non-Māori, non-Pacific 0.3 1.6 1.4 7.4 6.0 17.2 2.0 6.9
All ethnic groups 0.5 2.9 2.2 10.2 7.4 19.3 2.6 8.6
The gap for regular dispensing of urate-lowering therapy is greater for Māori and Pacific peoples than for non-Māori, non-Pacific populations with gout.
  • People experience urate-lowering benefits when therapy is used continuously long-term. Any dispensing was defined as people dispensed medicine in one quarter in a year. Regular dispensing was defined as people dispensed medicine in three or four quarters in a year. Regular dispensing indicates medicine persistence, that is, the availability to medicine a person has over the year.
  • While Māori and Pacific peoples were more likely to receive urate-lowering therapy in 2018 (59 percent) than non-Māori, non-Pacific populations (56 percent), they were less likely to receive it regularly. Māori (40 percent) and Pacific peoples (35 percent) regularly received urate-lowering therapy compared with non-Māori, non-Pacific populations (44 percent).
  • Rate of regular use increased significantly with age.

Table 2: Percent of people identified as having gout, who were dispensed a urate-lowering therapy in a year, and regularly in a year, by age and ethnicity, 2018

Dipensing type Age and ethnicity
20–44 years 45–64 years 65+ years All age groups
Māori Pacific Non-Māori, non-Pacific Māori  Pacific   Non-Māori, non-Pacific Māori  Pacific  Non-Māori, non-Pacific  Māori  Pacific  Non-Māori, non-Pacific 
Any dispensing 47 51 44 59 60 53 67 64 59 59 59 56 
Regular dispensing  15 17 20 38 37 38 56 53 51 40 35 44
  • The difference between ethnic groups was especially visible for those aged 20–44 years, where there is a much higher burden of identified gout in Māori and Pacific peoples, particularly for men.
  • There is inequity in the occurrence of gout across all age groups. The inequity in persistence of use of urate-lowering therapy when considering all age groups raises questions as to what is needed to address it.
NSAIDs were dispensed to 38 percent of those identified as having gout. Māori and Pacific peoples were dispensed more NSAIDs.
  • In 2018, 38 percent of people identified as having gout were dispensed an NSAID compared with 23 percent for the resident population aged 20 years and over.
  • There was limited regional variation.
  • People identifying as non-Māori, non-Pacific used statistically fewer NSAIDs – 35 percent of those with gout, compared with 46 percent of Pacific peoples and 41 percent of Māori.
  • Younger people, particularly Māori and Pacific peoples, were dispensed significantly more NSAIDs. These findings should be taken in the context of the inequity in persistence of urate-lowering therapy in younger Māori and Pacific peoples.
An NSAID without any urate-lowering therapy was dispensed in 15 percent of people identified as having gout.
  • On average, 15 percent of people with gout received an NSAID in a year without any urate-lowering therapy being dispensed.
  • Rates did not vary widely by ethnicity but did decrease with age.
Māori and Pacific peoples with gout were more likely to receive colchicine, prednisone or NSAIDs but less likely to receive them without any urate-lowering therapy.
  • In 2018, on average 55 percent of those with gout received either colchicine, prednisone or an NSAID. Only 22 percent received one of these but not urate-lowering therapy.
  • For all age groups, Pacific peoples with gout were more likely to receive colchicine, prednisone or an NSAID (62 percent), followed by Māori (59 percent). This dropped to 52 percent for those identifying as non-Māori, non-Pacific.
Serum urate was tested in the six months following urate-lowering therapy dispensing in 57 percent of people identified as having gout.
  • On average, three in five people identified as having gout received a serum urate test within six months of being dispensed urate-lowering therapy.
  • For gout to be treated effectively long term, there is a serum urate target of < 0.36 mmol/L.
  • There was 2.2-fold variation between DHBs.
  • Rates of testing did not vary widely by ethnicity but increased with age.

Note: The Equity Explorer (www.hqsc.govt.nz/atlas/equity-explorer) reports on people with gout whose serum urate was tested in the six months following allopurinol dispensing. The indicator in the report is not the same. It does not include point-of-care testing because only laboratory data on testing is available.

Māori and Pacific peoples had at least five times as many hospital admissions for gout.
  • Pacific peoples had over 10 times as many hospital admissions as non-Māori, non-Pacific populations, while Māori had more than five times as many.
  • Admissions increased with age. The variation was widest by DHB and by ethnicity in the 65 and over age group.

Background

Gout is the most common form of inflammatory arthritis. It is caused by an inflammatory response to monosodium urate (MSU) crystals, which form in the presence of high urate concentrations. Patients typically present initially with recurrent flares of severe joint inflammation. Over time, in the presence of elevated serum urate concentrations (hyperuricaemia), tophi, chronic arthritis and joint damage can occur.

Gout is estimated to affect approximately 5 percent of adult New Zealanders. Rates of gout are particularly high in Māori and Pacific men, affecting more than one-third of those aged 65 years and over.[2] Gout flares are extremely painful and disrupt work and home life. Tophaceous gout causes bone and joint damage and musculoskeletal disability.[2–4]

Long-term urate-lowering therapy is recommended for patients with recurrent gout flares (> 1/year), chronic gouty arthritis and joint damage. Allopurinol is the first-line urate-lowering therapy drug in New Zealand, but probenecid, benzbromarone and febuxostat are also effective. You need a target serum urate of < 0.36mmol/L to dissolve MSU crystals, suppress gout flares and for tophi to regress. Gout flares can be treated with NSAIDs, colchicine or corticosteroids.

Other indicators of the quality of gout management include the frequency of serum urate monitoring,[5] the use of NSAIDs and the rate of hospital admissions with gout as the primary diagnosis.

For each of the indicators, it was not possible to assess whether medicine was clinically indicated, whether the dose was optimal or whether the dose was taken. The methodology used can be downloaded here (325KB, pdf).

The rates for Asian populations were similar to the European/Other group, and in some DHBs Asian populations were small, so we have combined these into a non-Māori, non-Pacific group.

Recent research has found that genetics were significantly more likely than unhealthy foods to lead to higher urate levels.[6]

Links

Health Navigator regional pathways
BPAC: Managing gout in primary care, part 1
BPAC: Managing gout in primary care, part 2
BPAC guidance: An update on the management of gout

Recommended reading

Dalbeth N, Gerard C, Gow P et al. 2016. Gout in Aotearoa New Zealand: are we going to ignore this for another 3 years? NZMJ 129(1429): 10–13.
Dalbeth N, Dowell A, Gerard C, et al. 2018. Gout in Aotearoa New Zealand: the equity crisis continues in plain sight. NZMJ 131(1485): 8–12.
Jackson G, Dalbeth N, Te Karu L, et al. 2014. Variation in gout care in Aotearoa New Zealand: a national analysis of quality markers. NZMJ 127(1404): 37-47.
Lawrence A, Scott S, Saparelli F, et al. 2019. Facilitating equitable prevention and management of gout for Māori in Northland, New Zealand, through a collaborative primary care approach. J Prim H C 11(2): 117–27.
Winnard D, Wright C, Taylor W, et al. 2012. National prevalence of gout derived from administrative health data in Aotearoa New Zealand. Rheumatology 51(5): 901–9.

In the media

Te Karere TVNZ story: Research suggests equity issues around gout treatment: https://www.youtube.com/watch?v=KBhnHDF9HDo.
E-tangata. The shameful treatment of gout in New Zealand: https://e-tangata.co.nz/comment-and-analysis/the-shameful-treatment-of-gout-in-new-zealand/
Māori and Pacific peoples more likely to suffer from gout, less likely to be treated: https://www.waateanews.com/waateanews/x_story_id/MjA1NzA=/Māori-and-Pacific-peoples-more-likely-to-suffer-from-gout,-less-likely-to-be-treated
South Auckland providers responding to gout: www.hqsc.govt.nz/our-programmes/primary-care/news-and-events/news/3166

References and notes

  1. The potential relationship of the method of identifying people with gout to the increasing prevalence. As appropriate dispensing of urate-lowering therapy has increased in line with best practice, and dispensing of urate-lowering therapy is used in the algorithm to identify people with gout, this will contribute to the apparent increase in prevalence, alongside a real increase in prevalence.
  2. Lindsay K, Gow P, Vanderpyl J, et al. 2011. The experience and impact of living with gout: a study of men with chronic gout using a qualitative grounded theory approach. J Clin Rheumatol 17(1): 1–6.
  3. Martini N, Bryant L, Te Karu L, et al. 2012. Living with gout in New Zealand: an exploratory study into people's knowledge about the disease and its treatment. J Clin Rheumatol 18(3): 125–9.
  4. Dalbeth N, House ME, Horne A, et al. 2013. The experience and impact of gout in Maori and Pacific people: a prospective observational study. Clin Rheumatol 32(2): 247–51.
  5. Dalbeth N, Winnard D, Gow PJ, et al. 2015. Urate testing in gout: why, when and how. NZMJ 128(1420): 65–8.
  6. Major TJ, Topless RK, Dalbeth N, Merriman TR. 2018. Evaluation of the diet wide contribution to serum urate levels: Meta-analysis of population based cohorts. BMJ 2018; 363:k3951. URL: https://www.bmj.com/content/363/bmj.k3951 (accessed 6 November 2018).

Last updated 12/05/2020