Stress resilience is linked to increased risk of psoriasis

Young adults who find it harder to cope with stress are more likely to develop psoriasis later in life. Low stress resilience when enlisting for military service involves a 31% higher risk of developing psoriasis compared to high stress resilience. This has been shown by a large register-based study at the University of Gothenburg.

The study is based on data from more than 1.6 million Swedish men who enlisted for military service between 1968 and 2005.

As part of the enlistment process, all the men underwent psychological assessment in accordance with the same strict template. Based on this assessment, the researchers divided up the data on the men’s stress resilience into three levels. A fifth (20.4%) of those who enlisted were placed in the lowest group, and a further fifth (21.5%) were placed in the highest group. More than half were therefore placed in the intermediate group. Data relating to the men was then cross-checked with other registers. The National Patient Register was used to obtain the diagnosis codes for psoriasis and the joint disease psoriatic arthritis.

Around 36,000 of the men developed psoriasis or psoriatic arthritis later in life. Low stress resilience in men involves a 31% higher risk of developing psoriasis compared to high stress resilience.

More severe cases of psoriasis and psoriatic arthritis were also found to be particularly clearly linked to stress. For in-patient diagnoses, low stress resilience meant a 79% higher risk of psoriasis and a 53% higher risk of psoriatic arthritis compared to high stress resilience.

Psychological sensitivity

This is the first study to date supporting the hypothesis that sensitivity to stress is a risk factor for psoriasis. As psoriasis is a chronic inflammatory systemic disease, the link to stress could be due to an increased inflammatory response in the body.

“We have shown that lower stress resilience in adolescence is a potential risk factor for psoriasis, at least for men,” says the study’s lead author Marta Laskowski, a doctoral student in dermatology at the University of Gothenburg and a resident physician at Sahlgrenska University Hospital. “Our results suggest that those with psoriasis have a hereditary psychological sensitivity. It is therefore important that healthcare professionals also pay attention to the mental wellbeing of patients with psoriasis.”

When estimating the increased risk, the researchers adjusted for other risk factors such as BMI and socioeconomic factors. However, the study could only be adjusted indirectly for smoking, which is a well-known risk factor for psoriasis. The researchers note that one weakness of the study is that stress resilience was only tested on one occasion, at the time of enlistment when the men were 18 years old.

“Stress resilience can vary throughout life,” adds Marta. “However, we have not had the opportunity to investigate these changes.”

The results of the study have been published in the Journal of the European Academy of Dermatology and Venereology.

Scaly skin plaques

Around 300,000 Swedes have mild, moderate, or severe psoriasis. It is as common among women as it is among men. It is not fully known what triggers the disease, but we do know that heredity in combination with external factors plays a major role. The most common type is called plaque psoriasis, which causes red, scaly, itchy plaques on the skin.

Those who suffer from psoriasis often also have other diseases. Around 30% develop psoriatic arthritis, an inflammatory joint disease. Other known comorbidities include obesity, cardiovascular disease, diabetes, and depression.