Psoriasis is a chronic inflammatory skin condition characterized by the rapid buildup of skin cells, leading to thick, scaly, and often painful patches. Classified as an immune-mediated disease, the body’s immune system mistakenly triggers inflammation and accelerates the skin cell life cycle. Although the overall prevalence is similar between men and women, medical data consistently suggest that men experience greater severity and burden from the disease. This difference points to underlying biological and systemic factors that modulate the inflammatory response based on sex.
Quantifying Increased Disease Burden in Men
The increased severity in men is measurable through standard dermatological assessment tools. The Psoriasis Area and Severity Index (PASI) score measures redness, thickness, scaling, and overall body surface area (BSA) affected. Studies consistently show that men present with a statistically significantly higher median PASI score compared to women at diagnosis or enrollment in treatment registries. For instance, data indicate men often have median PASI scores around 7.3, whereas women’s scores are closer to 5.4.
This objective difference is reflected in treatment patterns. Men are frequently overrepresented in registries for systemic therapies, which are reserved for more extensive or severe cases. While women sometimes report a greater impact on their quality of life, men’s higher PASI and BSA scores confirm a greater physical disease burden. This necessitates more aggressive treatment options and provides the basis for investigating the biological mechanisms driving this sex-specific difference.
Influence of Sex Hormones on Inflammation
Differences in sex hormone profiles contribute directly to how the body manages chronic inflammation. Female hormones, particularly estrogen, have an anti-inflammatory or protective effect on the immune system. Estrogen influences the balance of immune cells, promoting a less aggressive immune response. This protective effect is evident in women, as high estrogen levels, such as those during pregnancy, are associated with improved psoriatic symptoms.
Conversely, the male hormone testosterone has a complex relationship with psoriasis. Studies observe that men with psoriasis often have lower total testosterone levels, and this deficiency is associated with greater disease severity. Testosterone replacement therapy in hypogonadal men has been shown to improve skin lesions, suggesting that adequate levels of the hormone may exert an anti-inflammatory action. The hormonal environment in men appears less protective against chronic inflammation than the estrogen-influenced environment in women.
Differences in Immune System Response
Underlying differences in the fundamental immune system architecture likely contribute to the severity gap. Psoriasis is driven by an overactive T-cell-mediated response, particularly involving the interleukin-23/interleukin-17 (IL-23/IL-17) inflammatory pathway. This pathway is a central driver of the thick, scaly plaques characteristic of the condition. The expression and activity of these key inflammatory molecules, such as IL-17 and Tumor Necrosis Factor-alpha (TNF-alpha), have been shown to differ between the sexes.
In men, the inflammatory cascade appears more vigorous or dysregulated, leading to a more aggressive disease phenotype. Research indicates that men with psoriasis have higher serum levels of IL-17 compared to women with the condition. The synergistic action of IL-17 and TNF-alpha is potent in promoting pathological skin changes. While both sexes rely on the same immune pathways, the male immune regulatory environment is less effective at suppressing the inflammation initiated by these cytokines.
The Greater Systemic Health Impact
The greater severity of skin disease in men is compounded by a heightened risk profile for associated systemic health conditions, known as comorbidities. Psoriasis is recognized as a systemic inflammatory disease, where chronic inflammation affects other organs, increasing the risk for cardiovascular disease and metabolic syndrome. Men with psoriasis face a higher risk of ischemic coronary heart disease compared to women with the condition.
The severity of psoriasis, as measured by PASI score, is directly linked to an increased risk of cardiovascular events, including heart attack and stroke. Since men generally have higher PASI scores, they are disproportionately affected by this link between severe skin inflammation and cardiovascular risk. Furthermore, men with psoriasis are more susceptible to the broader effects of systemic inflammation, which can exacerbate other risk factors like hypertension and dyslipidemia, contributing significantly to a heavier overall disease burden.