1. Metabolic syndrome and risk of incident psoriasis: prospective data from the HUNT Study, Norway
Ingrid Snekvik1,2, Tom I L Nilsen1, 3, Pål R Romundstad1, Marit Saunes2, 4
1. Department of Public Health and Nursing, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Norway
2. Department of Dermatology, St. Olavs Hospital, Trondheim University Hospital, Norway
3. Clinic of Anaesthesia and Intensive Care, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
4. Department of Cancer Research and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
British Journal of Dermatology. DOI: /bjd.16885

2. Lead author: PhD Student/Dermatologist Ingrid Snekvik

3. Introduction What’s already known?
Metabolic syndrome has been associated with psoriasis in cross- sectional studies, limited data from prospective studies

4. Objective
To prospectively examine whether metabolic syndrome and its components are associated with risk of incident psoriasis

5. Methods
The HUNT Study: includes all inhabitants in one Norwegian county
Used data from:
HUNT2 ( ), 93,898 were invited & 65,237 (70%) participated
HUNT3 ( ), 93,860 were invited 50,807 (54%) participated
Study population:
After exclusions: 34,996 individuals were included for statistical analyses

6. Methods Baseline: HUNT2
Questionnaires
Objectively measured height, weight, waist circumference, blood pressure and blood samples
374 incident psoriasis cases identified between HUNT2 and HUNT3

7. Methods
Cox regression to calculate hazard ratios as estimates of relative risk (RR) for incident psoriasis between categories of metabolic syndrome (yes/no) and number of metabolic factors
RR of psoriasis associated with the separate components of metabolic syndrome
Adjusted for age, sex, education, smoking and BMI

8. Results
Metabolic syndrome was associated with RR for psoriasis of (95% CI )
After excluding waist circumference from the definition of metabolic syndrome and adjusting for BMI, the RR was 1.33 (95% CI )
Positive association between the number of metabolic factors and risk of psoriasis

9. Results
Analyses of the separate components of metabolic syndrome showed:
positive associations with risk of psoriasis for waist circumference, triglycerides and high-density lipoprotein (HDL) cholesterol
Highest risk for increased waist circumference: RR 1.68 (95% CI 1.30, 2.17)
No association for blood pressure and blood glucose

10. Results Increased risk of psoriasis for high total cholesterol
The increased risk associated with high triglycerides, HDL cholesterol and total cholesterol was attenuated after adjusting for BMI

11. Discussion Strengths: Population based design, both women and men
Prospective design with long follow-up
Objective measurements
Adjustment for confounders

12. Discussion Limitations: Self-reported age at onset of psoriasis
Non-fasting state of blood sampling
Participants needed to have attended both HUNT2 and HUNT3, which leads to possibility of selection bias

13. Conclusions What does this study add?
Metabolic syndrome was associated with increased risk of incident psoriasis
A substantial part of this association seems to be attributable to adiposity

14. The research team: Professor Tom Ivar Lund Nilsen
Professor Paal R Romundstad
Associate professor/Dermatologist Marit Saunes

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