Moderate to severe psoriasis linked to chronic kidney disease, say experts

Moderate to severe psoriasis is associated with an increased risk of chronic kidney disease independent of traditional risk factors, such as diabetes and heart disease, finds a study published in BMJ today.

The authors recommend closer monitoring for kidney problems in patients with 3% or more of their body surface area affected to help detect and treat signs early and suggest careful consideration of medications which may cause in this at risk patient population.

Psoriasis is a common, chronic inflammatory disease of the skin and joints that affects 2-4% of the general population. Increasing evidence suggests that is associated with diabetes and independent of traditional risk factors. Some doctors think psoriasis may also be associated with kidney disease, but so far, studies have been small and shown conflicting results.

So a team of researchers based in Philadelphia, USA decided to compare the risk of in patients with and without psoriasis.

Using a UK primary care electronic medical records database (THIN), they identified 143,883 patients aged 18 to 90 years with psoriasis. These patients were matched with 689,702 patients without psoriasis who acted as controls. Patient with psoriasis who received phototherapy or oral or injectable (biologic) medications were defined as having severe disease.

The team then analysed how many of these patients had received a diagnosis of chronic kidney disease based on standard tests between 2003 and 2010.

Known risk factors for chronic kidney disease, such as age, sex, presence of , high blood pressure, high cholesterol levels, and use of NSAIDs were also taken into account.

The researchers found that patients with psoriasis, particularly those with severe disease, were at greater risk of developing moderate to advanced (stage 3 to 5) chronic kidney disease compared with control patients. Furthermore, those with severe psoriasis were nearly twice as likely to develop chronic kidney disease and were more than four times as likely to develop end stage renal disease requiring dialysis.

After adjusting for known risk factors, severe psoriasis remained an independent risk factor for chronic kidney disease and end stage renal disease requiring dialysis.

A further analysis of 8,731 psoriasis patients with measurements of affected body surface area matched to 87,310 patients without psoriasis showed similar results - a greater risk of chronic kidney disease in patients with moderate and severe disease.

Mild psoriasis is defined as limited disease with 2% or less body surface area affected, moderate as scattered disease with 3-10% body surface area affected and severe as extensive disease with more than 10% area affected.

The combined results indicate that, although no association is seen in patients with truly mild disease, associations are seen in moderate and , which are estimated to affect over 20% of patients worldwide, say the authors.

They also point out that, although the relative risk was higher in younger patients, the absolute risk of chronic kidney disease attributable to psoriasis increases with age.

For example, in patients aged 40-50 with severe disease, psoriasis accounts for one extra case of chronic kidney disease per 134 patients per year, and in those aged 50-60, it accounts for one additional case per 62 per year, they explain.

"Future studies are warranted to confirm our findings, determine the mechanisms mediating renal insufficiency in psoriasis, and examine the impact of treatment for psoriasis on the risk of chronic kidney disease," they conclude.

More information: www.bmj.com/cgi/doi/10.1136/bmj.f5961

add to favorites email to friend print save as pdf

Related Stories

Psoriasis patients at high risk of diabetes

Aug 27, 2012

Patients with psoriasis are at high risk of new-onset diabetes mellitus, according to research presented at ESC Congress 2012. The findings were presented at the press conference by Dr Ole Ahlehoff from Copenhagen University ...

Psoriasis increases risk of diabetes: study

Jun 18, 2012

Psoriasis is an independent risk for Type 2 Diabetes, according to a new study by researchers with the Perelman School of Medicine at the University of Pennsylvania, with the greatest risk seen in patients with severe psoriasis. ...

Recommended for you

Researchers discover target for treating dengue fever

11 hours ago

Two recent papers by a University of Colorado School of Medicine researcher and colleagues may help scientists develop treatments or vaccines for Dengue fever, West Nile virus, Yellow fever, Japanese encephalitis and other ...

Tracking flu levels with Wikipedia

11 hours ago

Can monitoring Wikipedia hits show how many people have the flu? Researchers at Boston Children's Hospital, USA, have developed a method of estimating levels of influenza-like illness in the American population by analysing ...

User comments