Elsevier

Journal of Hepatology

Volume 51, Issue 4, October 2009, Pages 778-786
Journal of Hepatology

Prevalence, characteristics and severity of non-alcoholic fatty liver disease in patients with chronic plaque psoriasis

https://doi.org/10.1016/j.jhep.2009.06.008Get rights and content

Background / Aims

The association between NAFLD and psoriasis has never been explored in prospective epidemiological studies. The aim of this 2-phase study was to study the clinical features of NAFLD in patients with psoriasis.

Methods

Phase 1: Investigation of prevalence and characteristics of NAFLD in an unselected cohort of 142 adult Italian outpatients with psoriasis vulgaris. Phase 2: Comparison of the psoriasis cohort subgroup with NAFLD and an age- and body mass index-matched retrospective cohort of 125 non-psoriasis patients with biopsy proven NAFLD.

Results

Based on histories, laboratory tests, and ultrasound studies, 84 (59.2%) received clinical diagnosis of NAFLD; 30 had factors potentially associated with liver disease other than NAFLD (e.g., viral hepatitis, significant ethanol, methotrexate use); and 28 (19.7%) had normal livers. Comparison of the normal-liver and NAFLD subgroups revealed that NAFLD in psoriasis patients (Ps-NAFLD) was significantly correlated with metabolic syndrome (p < 0.05); obesity (p = 0.043); hypercholesterolemia (p = 0.029); hypertriglyceridemia (p < 0.001); AST/ALT ratio >1 (p = 0.019), and psoriatic arthritis (PsA) (p = 0.036). The association with PsA remained significant after logistic regression analysis (OR = 3.94 [CI, 1.07–14.46]). Compared with the retrospective non-psoriatic NAFLD cohort (controls), Ps-NAFLD patients (cases) were likely to have severe NAFLD reflected by non-invasive NAFLD Fibrosis Scores and AST/ALT >1.

Conclusions

NAFLD is highly prevalent among psoriasis patients, where it is closely associated with obesity (overall and abdominal), metabolic syndrome, and PsA, and more likely to cause severe liver fibrosis (compared with nonPs-NAFLD). Routine work-up for NAFLD may be warranted in patients with psoriasis, especially when potentially hepatotoxic drug therapy is being considered.

Introduction

Psoriasis is a chronic inflammatory skin disease that affects 1–3% of the general population. It is characterized by epidermal hyperproliferation, abnormal keratinocyte differentiation, angiogenesis with vasodilatation, and activated CD4+ and CD8+ T-cell infiltrates in the dermis and epidermis, respectively [1]. The clinical presentation is highly variable in terms of lesion localization and severity, and in nearly one-third of all cases the skin lesions are associated with an inflammatory joint disease known as psoriatic arthritis (PsA).

Recent studies have linked psoriasis to obesity and the metabolic syndrome [2], [3], [4], [5] which are known risk factors for non-alcoholic fatty liver disease (NAFLD). The latter term refers to a broad spectrum of conditions ranging from simple fatty liver, which is relatively benign, to non-alcoholic steatohepatitis (NASH), which can give rise to fibrosis, cirrhosis, and end-stage liver disease. Anecdotal data suggest that NAFLD itself might also be associated with psoriasis [6], and an increased prevalence of this chronic liver disease might partly explain the increased risk of liver cirrhosis observed in this population [7].

Thus far, this link between NAFLD and psoriasis has never been explored in epidemiological studies. To eliminate this gap, we recently completed a two-phase study. Phase 1 consisted in a cross-sectional cohort analysis aimed at defining the prevalence and clinical features of NAFLD in psoriatic outpatients seen in a tertiary health-care center in Italy. This was followed by a non-interventional case-control study (Phase 2) conducted to compare the features of NAFLD in patients with and without psoriasis.

Section snippets

Study design

This study was conducted in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology guidelines [8] and the protocol was pre-approved by the institutional review board of the Catholic University of the Sacred Heart Medical Center in Rome, Italy. Informed consent was obtained from all study participants.

Study population

To determine the prevalence and characteristics of NAFLD associated with psoriasis (Ps-NAFLD), we recruited a cohort of patients from the Dermatology Outpatient

Characteristics of the psoriasis cohort

During the 2-year enrollment period, 231 adults with psoriasis were seen in the Dermatology Outpatient Clinic, and 142 (61.3%) agreed to participate in our study. Their characteristics are summarized in Table 1. All participants had psoriasis vulgaris, and almost one-third had PsA. Two-thirds had PASIs >10, which are correlated with common indicators of severe disease (e.g., need for hospitalization, use of systemic therapy). Fewer than 10% had received methotrexate, and all denied previous

Discussion

To our knowledge, this is the first independent, prospective, observational study on the potential association between NAFLD and psoriasis. The prevalence of clinically diagnosed NAFLD in our Italian psoriasis patients (59.2%) was markedly increased over rates observed in the general Italian population (20%) [18]. Indeed, NAFLD emerged as the number 1 liver disease in this cohort, with a frequency far higher than that of alcohol-related, viral, and autoimmune forms. Strong association between

Acknowledgement

This study was conducted with general research funds from Università Cattolica del Sacro Cuore, Rome, Italy.

References (34)

  • H.H. Roenigk et al.

    Methotrexate in psoriasis: consensus conference

    J Am Acad Dermatol

    (1998)
  • P. Rosenberg et al.

    Psoriasis patients with diabetes type 2 are at high risk of developing liver fibrosis during methotrexate treatment

    J Hepatol

    (2007)
  • J.M. Gelfand et al.

    Risk of myocardial infarction in patients with psoriasis

    JAMA

    (2006)
  • P. Gisondi et al.

    Prevalence of metabolic syndrome in patients with psoriasis: a hospital-based case-control study

    Br J Dermatol

    (2007)
  • B. Lindegård

    Diseases associated with psoriasis in a general population of 159,200 middle-aged, urban, native Swedes

    Dermatologica

    (1986)
  • T. Fredriksson et al.

    Severe psoriasis – oral therapy with a new retinoid

    Dermatologica

    (1978)
  • D.R. Matthews et al.

    Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man

    Diabetologia

    (1985)
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    The authors who have taken part in this study declared that they do not have anything to disclose regarding funding from industry or conflict of interest with respect to this manuscript.

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    These authors contributed equally to this work.

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    These authors shared senior authorship.

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