The age of onset for psoriasis is highly variable, ranging from early infancy to advanced age, with the most common onset occurring during puberty[14] Approximately 70% of patients experience the first symptoms of psoriasis before the age of 40, most frequently in the second to third decades of life[15] A study reported that in 30% of patients, the disease begins before the age of 16 [16] In our study, the observation that 71% of patients had early-onset psoriasis is consistent with the literature.Additionally, a family history of psoriasis was found in 43.7% of early-onset patients, compared to 16.4% of late-onset patients. This finding aligns with literature reports indicating that a family history is more common in early-onset psoriasis patients[2], [17]
Our study corroborates findings from Ferrándiz et al.[5], demonstrating a higher prevalence of pustular subtypes in late-onset psoriasis. This aligns with their observation that palmoplantar pustulosis predominantly affects patients with disease onset after 30 years of age[5] The correlation suggests that age-related factors may influence the manifestation of specific psoriasis subtypes. Additionally, the same study found no association between joint involvement and the age of disease onset, which aligns with our findings as we also did not observe such an association. Another parameter associated with late-onset age in our study was an increase in BMI. This finding is consistent with the results reported by Herédi et al., who found that obesity is more common in patients with late-onset psoriasis compared to those with early-onset psoriasis[18] This suggests that obesity may be a contributing factor to the development of psoriasis at an older age.
Early-onset psoriasis has been associated with higher genetic predisposition, a more severe disease course, and greater psychosocial comorbidity in the literature [3], [4], [5]. However, different studies have used varying threshold ages to define early and late-onset psoriasis. In a study by Remröd et al.[4] involving 101 patients, psoriasis onset before the age of 20 was considered early-onset, while onset at 20 years and older was considered late-onset. Based on this classification, significant differences were found between early-onset and late-onset psoriasis groups in Spielberger State-Trait Anxiety Inventory scores, Beck Depression Inventory scores, and the seven personality types identified by the Swedish Universities Scales of Personality. According to these findings, early-onset patients (onset before 20 years of age) were more anxious and depressed compared to late-onset patients. The same study found no significant relationship between PASI scores and patients' depression and anxiety scores. Additionally, there was no association between the duration of psoriasis and levels of state-trait anxiety, severity of depression, or personality types[4].
However, in contrast to the study by Remröd et al.[4], our study did not find a statistically significant difference in depression and anxiety between the early-onset and late-onset psoriasis patient groups. One possible explanation for this could be the different age thresholds used in defining early and late-onset psoriasis. In a study involving 137 patients, Gupta et al. highlighted that early-onset disease (before the age of 40) is associated with difficulties in expressing feelings such as self-confidence and anger, compared to late-onset disease (after the age of 40). This personality trait can negatively impact the patients' capacity to cope with stress[3] In our study, the age threshold for early and late onset was set at 40 years, similar to the study by Gupta et al., and as first proposed by Henseler and Christophers in 1985 for defining early and late psoriasis.
Mizara et al.[19] reported maladaptive psychological behavior patterns specific to the early period in patients with psoriasis and suggested that unmet emotional and developmental needs in early life could create vulnerability to psychological stress in later years. In line with this, another study noted that children and adolescents often experience stigmatization and social difficulties due to their illness, suggesting that these negative experiences in childhood can affect personality development and lead to anxiety and depression in adulthood [20]. In our study, the presence of psychological stress as a trigger for psoriatic lesions was significantly more common in the early-onset group compared to the late-onset group. Our findings align with another study by Raychaudhuri and Gross[16], which compared pediatric-onset (< 16 years) and adult-onset (> 16 years) psoriasis. They emphasized that disease flare-ups were more frequent in pediatric-onset patients under psychological stress. The authors explained this by suggesting that emotional immaturity and lack of insight make younger patients more sensitive to psychological stress. In our study, the proportion of patients who associated the onset of psoriasis with a recent traumatic life event was significantly higher in the late-onset group. Several studies in the literature indicate that traumatic experiences may play a crucial role in the development and exacerbation of psoriasis[21], [22], [23]; however, the relationship with the age of disease onset has not been thoroughly investigated.
Kimball et al.[24] proposed the concept of Cumulative Life Course Impairment (CLCI) for psoriasis, which expresses the cumulative impact of the disease over a lifetime. According to this model, CLCI in psoriasis results from the complex interaction of external factors such as stigmatization, physical and psychological comorbidities, coping strategies, and the social environment. This lifelong accumulation of physical, psychological, social, and economic burdens influences major life decisions. Warren et al.[25] reported that early-onset psoriasis significantly impacts feelings of shame and stigmatization, as well as career choices, continuing education, and relationships with family and social circles, compared to late-onset psoriasis.
In our study, although no significant difference was found between early and late-onset psoriasis patients in terms of DLQI and HAD scores, the positive and significant correlation between DLQI and HAD-Total, HAD-A, and HAD-D supports the relationship between quality of life, depression, and anxiety reported in other studies in the literature[26], [27]. In the literature, various studies report that the proportion of patients who associate their disease with psychological stress ranges from 37–78%[28] The role of psychological stress in psoriasis can be explained by its induction of catecholamines and corticosteroids released from the hypothalamic-pituitary axis, leading to the release of neuropeptides from the skin through neuroendocrine, immune, and cutaneous interactions. However, the evidence for the relationship between psychosocial stress and psoriasis flare-ups is limited, as most data in the literature are based on anecdotal reports or retrospective studies [29], [30].
In our study, 63.1% of patients reported psychological stress as a trigger factor for psoriatic lesions, and this proportion was significantly higher in the early-onset psoriasis group. Our findings align with previous studies that indicate a significant role of stress in exacerbating psoriasis. Ferrándiz et al.[5] reported in a study involving 1,774 patients that trigger factors were more common in patients whose psoriasis onset occurred before the age of 30. Malhotra and Mehta[31] reported that stressful life events were noted in 26% of psoriasis vulgaris patients within a year preceding the onset or exacerbation of the disease. In the study by Consoli et al.,[32] 54.8% of patients identified various stressful events as triggers for their psoriasis lesions. In the same study, psychiatric comorbidities of patients were assessed using various scales, and no significant relationship was found between psychiatric comorbidities and identifying stress as a trigger. In contrast, in our study, patients who identified psychological stress as a triggering factor had higher HAD-Total, HAD-A, and HAD-D scores compared to those who did not identify stress as a trigger. The differences in the results may be related to the limitations of evaluating a complex and highly subjective experience like psychological stress using surveys with only one or a few questions. These findings underscore the importance of incorporating comprehensive stress management strategies into psoriasis treatment plans to mitigate the exacerbating effects of psychological stress on the disease and improve overall patient outcomes.