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Prevalence and stages of chronic kidney disease in psoriasis and psoriatic arthritis: A cross-sectional study
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Received: ,
Accepted: ,
How to cite this article: Munera-Campos M, Ferrándiz C, Mateo L, Prior-Español A, Carrascosa JM. Prevalence and stages of chronic kidney disease in psoriasis and psoriatic arthritis: A cross-sectional study. Indian J Dermatol Venereol Leprol 2021;87:321-321.
Sir,
A few retrospective cohort studies have reported an increased incidence of chronic kidney disease (CKD) in patients with psoriasis, independent of traditional cardiovascular risk factors and nephrotoxic drugs.1,2 However, those studies have relied mainly on secondary data which makes it impossible to stratify patients. Additionally, mild-to-moderate declines in estimated glomerular filtration rate (eGFR) were not reported.
Our aim was to describe the prevalence of eGFR stages and CKD in a representative cohort of patients with moderate-to-severe psoriasis, and to explore predictors of CKD.
We conducted a prospective, cross-sectional study in patients aged 20 or above who had been diagnosed with moderate-to-severe psoriasis on the basis of their need for phototherapy or systemic treatment (≥6 months) and/or psoriatic arthropathy. Participants were recruited from dermatology and rheumatology outpatient clinics at a tertiary University Hospital between October 2007 and May 2018. This study was approved by the Ethics Committee of our hospital.
We examined laboratory data of serum creatinine and eGFR using the Chronic Kidney Disease-Epidemiology Collaboration (CDK-EPI) formula. The criteria for CKD were an eGFR value under 60mL/min/1.73m2 on at least 2 occasions separated by at least 3 months. Acute kidney impairment was ruled out. To identify the risk factors associated with comorbid CKD, we performed univariate and multivariate logistic regression analyses (SPSS, v25). A P value of less than 0.05 was considered statistically significant.
Our study population included 558 patients: 221 (39.6%) had purely cutaneous psoriasis, 108 (19.4%) had only psoriatic arthropathy whereas 229 (41%) had both. Three patients with psoriatic arthropathy had concomitant renal amyloidosis. Characteristics and potential confounders have been summarised in Table 1.
| Feature | n(%) |
|---|---|
| Sex | |
| Male | 315 (56.5) |
| Female | 243 (43.5) |
| Age (years) range | |
| 20-39 | 71 (12.7) |
| 40-64 | 353 (63.3) |
| >64 | 134 (24) |
| Smoking status | |
| Current smoker | 135 (24.2) |
| Ex-smoker | 63 (11.3) |
| Non-smoker | 360 (64.5) |
| Alcohol intake | |
| Alcohol consumer | 117 (21) |
| Non-consumer | 441 (79) |
| BMI | |
| Obesity (BMI >30 kg/m2) | 144 (25.8) |
| Overweight (BMI 2530 kg/m2) | 135 (24.2) |
| Normal weight (BMI 18.5-24.9kg/m2) | 279 (50) |
| Comorbidities | |
| Hypertension | 158 (28.3) |
| Dyslipidaemia | 206 (36.9) |
| Ischaemic heart disease | 21 (3.8) |
| Diabetes | 82 (14.7) |
| Psoriasis duration (years) | |
| Duration >10 | 339 (60.8) |
| Clinical characteristics | |
| Psoriasis | 450 (80.7) |
| Chronic plaque psoriasis | 422 (93.8) |
| Guttate psoriasis | 12 (2.7) |
| Erythrodermic psoriasis | 5 (1.1) |
| Generalized pustular psoriasis | 6 (0.1) |
| Palmoplantar pustular psoriasis | 23 (5.1) |
| Psoriatic arthritis (all subtypes) | 337 (60.4) |
| Subtypes | |
| Oligoarthritis | 145 (43) |
| Polyarthritis | 94 (27.9) |
| Axial | 22 (6.5) |
| Oligoarthritis with axial involvement | 31 (9.2) |
| Polyarthritis with axial involvement | 34 (10.1) |
| Distant interphalangeal arthritis | 11 (3.3) |
| Comorbid manifestations | |
| Dactylitis | 116 (34.4) |
| Tendonitis | 129 (38.3) |
| Plantar fasciitis | 34 (10.1) |
| Enthesitis | 88 (26.1) |
| Coexisting renal amyloidosis | 3 (0.9) |
| Use of NSAIDs | |
| Non-user | 106 (19) |
| Low frequency user(<2 prescriptions/year) | 390 (69.9) |
| Moderately frequent user (2-5 prescriptions/year) | 50 (9) |
| Highly frequent user (>5 prescriptions/year) | 12 (2.2) |
| Treatments received >6 months | |
| Phototherapy | 155 (27.8) |
| Methotrexate | 372 (66.7) |
| Leflunomide | 108 (19.4) |
| Salazopyrin | 20 (3.6) |
| Hydroxychloroquine | 16 (2.9) |
| Cyclosporin | 47 (8.4) |
| Acitretin | 44 (7.9) |
| Apremilast | 13 (2.3) |
| Adalimumab | 74 (13.3) |
| Etanercept | 80 (14.3) |
| Infliximab | 28 (5) |
| Golimumab | 8 (1.4) |
| Certolizumab | 4 (0.7) |
| Ustekinumab | 50 (9) |
| Secukinumab | 16 (2.9) |
| Ixekizumab | 6 (1.1) |
| Efalizumab | 25 (4.5) |
BMI: Body mass index, NSAIDs: Nonsteroidal anti-inflammatory drugs
The overall prevalence of CKD was 15.2% (1.4% for age 20-39 years; 9.4% for age 40-64 years and 38.1% for age >64 years). In patients who had only skin disease, the prevalence of CKD was 9.5% compared with 18.8% in the group with skin disease and psoriatic arthropathy. Prevalence of eGFR as per staging is shown in Table 2. Unadjusted associations for CKD are shown in Table 3. On multivariate analysis, only age >64 years, hypertension and psoriatic arthropathy remained as independent predictors of CKD [Table 4].
| Prevalence of eGFR (mL/min/1.73 m2) distributed in categories and overall CKD. Expressed by n(%) | |||||||
|---|---|---|---|---|---|---|---|
| Normal (≥90) | Stage 2 (60-89) | Stage 3a (45-59) | Stage 3b (30-44) | Stage 4 (15-29) | Stage 5 (<15) | CKD (Stages 3-5) (overall <60) | |
| Total (n=558) | 219 (39.3) | 254 (45.5) | 58 (10.4) | 16 (2.9) | 9 (1.6) | 2 (0.4) | 85 (15.2) |
| Age (years) | |||||||
| 20-39 (n=71) | 45 (63.4) | 25 (35.2) | - | - | 1 (1.4) | - | 1 (1.4) |
| 40-64 (n=353) | 164 (46.5) | 156 (44.2) | 26 (7.4) | 5 (1.4) | 1 (0.3) | 1 (0.3) | 33 (9.4) |
| >64 (n=134) | 10 (7.5) | 73 (54.5) | 32 (23.9) | 11 (8.2) | 7 (5.2) | 1 (0.8) | 51 (38.1) |
| Sex | |||||||
| Male (n=315) | 124 (39.4) | 147 (46.7) | 34 (10.8) | 6 (1.9) | 4 (1.3) | - | 44 (14) |
| Female (n=243) | 95 (39.1) | 107 (44) | 24 (9.9) | 10 (4.1) | 5 (2.1) | 2 (0.8) | 41 (16.9) |
eGFR: Estimated glomerular filtration rate, CKD: Chronic kidney disease
| Characteristic (reference) | OR (95% CI) | P |
|---|---|---|
| Age >64 years (v/s ≤64 years) | 6.6 (4-10.7) | <0.001 |
| Age >64 years (v/s 20-39 years) | 43 (5.8-319.3) | <0.001 |
| Age 40-64 years (v/s 20-39 years) | 7.22 (1-53.7) | 0.02 |
| Men (v/s women) | 1.3 (0.8-2) | 0.344 |
| Alcohol consumer (v/s non-consumer) | 0.6 (0.3-1.2) | 0.163 |
| Current smoker (v/s non-smoker) | 1 (0.5-1.7) | 0.855 |
| Ex-smoker (v/s non-smoker) | 1.5 (0.8-3) | 0.233 |
| Obesity, BMI >30 kg/m2(v/s normal, 18.5-25 kg/m2) | 1.2 (0.7-2) | 0.538 |
| Overweight, BMI 25-30 kg/m2(v/s normal, 18.5-25 kg/m2) | 0.8 (0.5-1.5) | 0.510 |
| Hypertension (v/s absence) | 4.3 (2.7-6.9) | <0.001 |
| Dyslipidaemia (v/s absence) | 1.7 (1.1-2.8) | 0.019 |
| Ischaemic heat disease (v/s absence) | 2.9 (1.2-7.5) | 0.019 |
| Diabetes (v/s absence) | 2.8 (1.6-4.9) | <0.001 |
| Psoriatic arthritis (v/s absence) | 2.2 (1.3-3.8) | 0.002 |
| Disease duration >10 years (v/s ≤10 years) | 1 (0.6-1.5) | 0.877 |
| NSAIDs frequent user (2-5 prescriptions/y) (v/s nonuser) | 1 (0.4-2.4) | 0.991 |
| NSAIDs high-frequent user (>5 prescriptions/years) (v/s nonuser) | 0.9 (0.2-4.5) | 0.914 |
| Methotrexate (v/s absence) | 0.8 (0.5-1.3) | 0.359 |
| Leflunomide (v/s absence) | 1.1 (0.7-2) | 0.644 |
| Salazopyrin (v/s absence) | 0.8 (0.8-1) | 0.503 |
| Hydroxychloroquine (v/s absence) | 0.8 (0.2-3.5) | 0.758 |
| Cyclosporin (v/s absence) | 0.8 (0.3-2) | 0.623 |
| Acitretin (v/s absence) | 0.9 (0.4-2.1) | 0.759 |
BMI: Body mass index, CI: confidence interval, OR: Odds ratio, NSAIDs: Nonsteroidal anti-inflammatory drugs
| Predictor | OR (95 CI) | P |
|---|---|---|
| Age >64 years (v/s ≤64 years) | 4.7 (2.7-8.1) | <0.001 |
| Hypertension (v/s absence) | 2.3 (1.3-4) | 0.005 |
| Psoriatic arthritis | 2.5 (1.4-4.5) | 0.002 |
| Men (v/s woman) | 0.9 (0.5-1.5) | 0.682 |
| Alcohol consumer (v/s nonconsumer) | 1.4 (0.2-9.2) | 0.755 |
| Currently smoker (v/s nonsmoker) | 0.6 (0.1-4.4) | 0.581 |
| Exsmoker (v/s nonsmoker) | 1 (0.6-1.8) | 0.897 |
| Obesity, BMI >30 kg/m2(v/s normal, 18.5-25 kg/m2) | 0.9 (0.5-1.6) | 0.658 |
| Overweight, BMI 25-30 kg/m2(v/s normal, 18.5-25 kg/m2) | 0.5 (0.2-1.1) | 0.172 |
| Dyslipidaemia (v/s absence) | 1.3 (0.8-2.4) | 0.310 |
| Ischaemic heat disease (v/s absence) | 1.2 (0.4-3.8) | 0.719 |
| Diabetes (v/s absence) | 1.4 (0.7-2.8) | 0.306 |
| Disease duration >10 years (v/s ≤10 years) | 1.6 (0.9-2.8) | 0.147 |
| NSAIDs frequent user (2-5 prescriptions/years) (v/s nonuser) | 1.6 (0.8-3.3) | 0.164 |
| NSAIDs high-frequent user (>5 prescriptions/years) (v/s nonuser) | 1.4 (0.3-7.3) | 0.686 |
| Methotrexate (v/s absence) | 0.7 (0.4-1.2) | 0.189 |
| Leflunomide (v/s absence) | 0.6 (0.3-1.2) | 0.160 |
| Salazopyrin (v/s absence) | 0.5 (0.2-1.1) | 0.078 |
| Hydroxychloroquine (v/s absence) | 1.6 (0.8-3.2) | 0.208 |
| Cyclosporin (v/s absence) | 1.3 (0.5-3.5) | 0.663 |
| Acitretin (v/s absence) | 1.9 (0.7-5.4) | 0.238 |
BMI: Body mass index, CI: confidence interval, OR: Odds ratio, NSAIDs: Nonsteroidal anti-inflammatory drugs
A total of 85 patients (15.2%) had CKD. Although the study lacks a control group, the prevalence of CKD and of mildly decreased eGFR found are higher than those in the general population.3 We also found an overall prevalence of 45.5% for stage 2 eGFR, a relatively high percentage compared to data from the general population, particularly in younger individuals (35.2% for age 20-39 years). Cardiovascular mortality increased linearly when eGFR decreased to below 75 mL/min/1.73m2, independent of traditional cardiovascular risk factors and albuminuria.4 In this study group, 30.7% patients had results below this threshold (5.6% for age 20-39 years; 24.6% for age 40-64 years; and 59.7% for age >64 years), a finding that could be associated with an increased cardiovascular risk.
The three independent predictors of CKD were age >64 years, hypertension and psoriatic arthropathy. Although eGFR decreases with age, the prevalence of CKD over 64 years of age in our study group (38.1%) is higher than what is reported for the general population (21.4%).
It has been hypothesised that the decrease in eGFR in patients with psoriasis may be due to an increase in systemic cytokines (tumor necrosis factor-α and interleukin-6) and endothelial dysfunction, which has been associated with an increase in fibroblast growth factor-23.2 In our study group, the presence of psoriatic arthropathy increased the risk of CKD (odds ratio, 2.5) after adjustment for conventional risk factors and nephrotoxic drugs. Psoriatic arthropathy may increase chronic inflammation more than psoriasis without arthropathy.
This study is limited by the small sample size and the lack of a control group. Nonetheless, it includes a cohort undergoing close monitoring, which allowed us to stratify eGFR stages and to obtain the prevalence of CKD defined by eGFR (using the CKD-EPI equation, which has been shown to be more accurate than other formulae).5 Moreover, the eGFR classification was based on 2 values obtained more than 90 days apart and acute renal impairment was systematically ruled out.
To conclude, the prevalence of CKD among patients with moderate-to-severe psoriasis and/or psoriatic arthropathy is high. Age over 64 years and the presence of hypertension may predict an increased likelihood of CKD. In other words, psoriasis could increase the likelihood of renal impairment in patients with conventional cardiovascular risk factors and the presence of psoriatic arthropathy may be associated with additional risk. Mildly decreased eGFR was highly prevalent and could increase cardiovascular risk in these patients. Our findings suggest that renal and cardiovascular risk factors should be taken into consideration in cases of moderate-to-severe forms of psoriasis.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
- Increased risk of glomerulonephritis and chronic kidney disease in relation to the severity of psoriasis, concomitant medication, and comorbidity: A nationwide population based cohort study. Br J Dermatol. 2015;173:146-54.
- [CrossRef] [PubMed] [Google Scholar]
- Risk of moderate to advanced kidney disease in patients with psoriasis: Population based cohort study. BMJ. 2013;347:f5961.
- [CrossRef] [PubMed] [Google Scholar]
- Prevalence and management of chronic kidney disease in primary care patients in the UK. Int J Clin Pract. 2014;68:1110-21.
- [CrossRef] [PubMed] [Google Scholar]
- Chronic kidney disease and cardiovascular risk: Epidemiology, mechanisms, and prevention. Lancet. 2013;382:339-52.
- [CrossRef] [Google Scholar]
- Estimating GFR using the CKD Epidemiology Collaboration (CKD EPI) creatinine equation: More accurate GFR estimates, lower CKD prevalence estimates, and better risk predictions. Am J Kidney Dis. 2010;55:622-7.
- [CrossRef] [PubMed] [Google Scholar]
