BackgroundPsoriatic arthritis (PsA) is associated with an accumulation of cardiovascular disease (CVD) risk factors. The aim of this study was to evaluate the effect of high-intensity interval training (HIIT) on CVD risk factors in patients with PsA.MethodsWe randomly assigned 61 patients with PsA (41 women and 20 men) to an intervention group performing HIIT for 11 weeks or a control group who were instructed to not change their physical exercise habits. Outcomes were assessed at 3 and 9  months with measures on maximal oxygen uptake (VO2max), fat percentage and Body Mass Index (BMI). We used linear mixed models to calculate mean difference with 95% CI between the groups according to the intention-to-treat principle.ResultsAt 3  months, the HIIT group had a 3.72  mL/kg/min (95%  CI 2.38 to 5.06) higher VO2max and a 1.28 (95% CI −2.51 to −0.05) lower truncal fat percentage than controls. There was also some evidence that the HIIT group had lower total fat percentage (−0.80; 95%  CI −1.71 to 0.10) and slightly lower BMI (−0.31; 95%  CI −0.78 to 0.17) than the control group. At 9  months, the HIIT group had still a higher VO2max (3.08; 95%  CI 1.63 to 4.53) than the control group, whereas the difference in other factors were small.ConclusionIn patients with PsA, 3  months with HIIT was associated with a substantial increase in VO2max and a reduction in truncal fat percentage compared with controls. The beneficial effect on VO2max was also sustained through 9  months.Trial registration numberNCT02995460.

HIIT showed no clear effects on disease activity markers in patients with PsA, but the exercise group reported meaningfully less fatigue after the intervention period. This study suggests that PsA patients tolerate HIIT without deterioration of disease activity and with improvement in fatigue. This article is protected by copyright. All rights reserved.

Objective Adiposity is prevalent among patients with psoriatic arthritis (PsA). However, the temporal relation is unclear. The present study was undertaken to investigate whether adiposity and body fat distribution are related to the risk of developing PsA, and whether physical activity could modify the possible risk. Methods We included 36,626 women and men from the Norwegian Nord‐Trøndelag Health Study without diagnosed PsA at baseline from 1995 to 1997. Cox regression analysis was used to estimate adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) of incident PsA at follow‐up from 2006 to 2008. Results During follow‐up, 185 new cases of PsA were reported. Increases of 1 SD in body mass index (BMI) (4.2 and 3.5 kg/m2 for women and men, respectively) and waist circumference (10.8 and 8.6 cm, respectively) were associated with HRs of 1.40 (95% CI 1.24, 1.58) and 1.48 (95% CI 1.31, 1.68), respectively. Compared to individuals of normal weight, obese individuals had an HR of 2.46 (95% CI 1.65, 3.68), and overweight individuals had an HR of 1.41 (95% CI 1.00, 1.99). Comparing extreme quartiles of waist circumference yielded an HR of 2.63 (95% CI 1.73, 3.99). In analyses of combined effects using a BMI of <25 kg/m2 and high physical activity as reference, a BMI of ≥25 kg/m2 was associated with HRs of 2.06 (95% CI 1.18, 3.58) and 1.53 (95% CI 0.80, 2.91) among those with low and high physical activity levels, respectively. Corresponding HRs for high waist circumference and physical activity were 2.25 (95% CI 1.40, 1.63) and 1.85 (95% CI 0.95, 3.50). Conclusion The results suggest that adiposity, particularly central obesity, is associated with increased risk of incident PsA. Although there was no clear modifying effect of physical activity, high levels of physical activity reduced the risk of PsA, regardless of BMI.