**3.1 Psoriasis and metabolic syndrome**

Psoriasis has long been recognized as a chronic immune-mediated multi-systemic inflammatory disorder, associated with numerous comorbidities *viz.* Crohn's disease,

## *Th17/IL-17, Immunometabolism and Psoriatic Disease: A Pathological Trifecta DOI: http://dx.doi.org/10.5772/intechopen.102633*

depression, cardiovascular disease, and metabolic syndrome [22]. A concept of 'psoriatic march' was postulated by Boehncke et al. for this inflammatory cascade to highlight the series of systemic inflammatory effects and their relationship with obesity and metabolic syndrome [23]. Metabolic syndrome represents a spectrum of metabolic complications encompassing obesity, hypertension, type 2 diabetes, insulin resistance, atherogenic dyslipidemia and non-alcoholic fatty liver disease (NAFLD) [21]. A recent metanalysis of 63 studies encompassing 15,939 psoriasis patients and 103,984 controls reported a significant association of psoriasis and metabolic syndrome (Odds ratio: 2.077; 95% confidence interval: 1.84–2.34) emphasizing regular monitoring of psoriatic patients for metabolic syndrome complications, including increased fasting plasma glucose levels, raised triglyceride levels, lowered high density cholesterol (HDL) levels, hypertension, and waist circumference [24]. Concurrent occurrence of these metabolic complications in psoriatic patients increases their risk of developing micro and macrovascular adversities contributing to significant morbidity and mortality [25, 26]. Increasing evidence demonstrates a complex interplay among immune cells with attendant aberrant immune dysfunction (such as is seen in psoriasis) and altered cellular and systemic metabolic axes across various organ systems, including adipose tissue, in triggering both local and systemic inflammation [27].
