Nonalcoholic fatty liver disease, spleen and psoriasis: New aspects of low-grade chronic inflammation

Abstract

Aim: To investigate spleen status in psoriasis and its relationship with hepatic steatosis, Psoriasis Area and Severity Index, and insulin resistance.

Methods: Seventy-nine psoriatic patients who were not suffering from any chronic inflammatory disease were retrospectively selected for inclusion in this study, and their complete medical records were accessed. An age- and sex-matched group of 80 non-psoriatic, obese patients was included as a control. The following relevant data were collected: age, sex, weight, height, body mass index, waist circumference, blood pressure, insulin resistance status, age at psoriasis onset, and severity of psoriasis. Abdominal ultrasonography was performed to determine spleen longitudinal diameter (SLD), and hepatic steatosis grade.

Results: The SLD of control obese patients was greater than that of psoriatic subjects (P = 0.013), but body mass index predicted the size of the spleen in psoriatic patients (P < 0.001). The SLD of psoriatic patients with normal weight was significantly reduced with respect to the overweight/obese psoriatic patients (P = 0.002). A multiple regression analysis revealed that body mass index was a unique predictor of the spleen size (P < 0.001). Finally, the disease duration predicted the spleen size in psoriatic subjects (P = 0.038).

Conclusion: This study shows a correlation between the SLD and the duration of psoriasis.

Keywords: Hepatic steatosis; Inflammation; Nonalcoholic fatty liver disease; Psoriasis; Spleen size.

Figure 1

Spleen size, body mass index, and hepatic steatosis. A: Spleen longitudinal diameter (SLD) in the psoriatic patients and obese controls; B: Prediction of body mass index (BMI) on SLD of patients with psoriasis (dotted lines near the regression line are the 95% confidence curves, the far ones are the 95% prediction curves); C: SLD in overweight/obese psoriatic patients (O/O) and normal weight (NW) psoriatic patients; D: Hepatic steatosis (HS) grade in patients (cases) and controls: grade 0 = absent; 1 = mild; 2 = moderate; 3 = severe. Boxes in A, C and D indicate the interquartile ranges and the transverse lines represent the median.

Figure 2

Insulin resistance, hepatic steatosis, spleen size, severity of psoriasis, and disease age of psoriatic patients. A: Prediction of insulin resistance on severity of psoriasis; B: Prediction of hepatic steatosis (HS) on severity of psoriasis; C: Prediction of SLD on severity of psoriasis; D: Prediction of disease age of psoriatic patients on SLD. Dotted lines near the regression line are the 95% confidence curves, the far ones are the 95% prediction curves. HOMA: Homeostatic metabolic assessment; PASI: Psoriasis area and severity index; SLD: Spleen longitudinal diameter.