POS0313 THE ASSOCIATION BETWEEN BODY COMPOSITION AND PHYSICAL ACTIVITY IN PATIENTS WITH PSORIATIC ARTHRITIS: THE TRØNDELAG HEALTH STUDY

Abstract

BackgroundPersons with psoriatic arthritis (PsA) have an altered body composition compared to the general population, including overweight, which may increase the risk of several comorbidities. However, the associations of physical activity (PA) with body composition among persons with PsA is not well described.ObjectivesThe aim of the study was to investigate the relationship between visceral fat mass (VFM) and percentage body fat (PBF), respectively, with PA in persons with PsA.MethodsThe study utilized data from the population-based Trøndelag Health Study (HUNT4, 2017-2019), where all inhabitants ≥ 20 years of age in northern Trøndelag were invited. Data comprised questionnaires, measurements, and blood sample analyses. Persons with PsA (n=291, CASPAR criteria) were identified from hospital case notes. The remaining participants with complete data for relevant variables (n=38 955) were used as controls.Body composition was measured using bioelectrical bioimpedance including 30 values for 5 body segments. The primary outcomes were VFM (Model 1) and PBF (Model 2). PA was quantified using an index based on self-reported frequency, duration, and intensity (1), and categorized as low, moderate, or high.Data were analyzed with multivariable linear regression including PsA and PA as exposures. The models were adjusted for age (<40, 40-59 >60 years), sex, alcohol consumption (once a week/more vs. less/none), smoking status (present/former vs. never smoker), diabetes, hypertension, heart disease, lung disease and cancer; and height (Model 1 only). To achieve appropriate model fit, an interaction term between age and PsA was included.ResultsPersons with PsA had higher weight, body mass index, VFM and PBF than controls, and they were less physically active (Table 1). The interaction term between PsA and age was statistically significant in both models (p<0.05), showing that the difference in VFM and PBF with PsA compared to controls was relatively larger in persons < 40 years (VMF difference: 3.6kg (95% CI 1.4, 5.9 kg) vs. ~1.1 kg in older age groups, PBF difference: 5.2% (1.9, 8.5%) vs. ~1.5% in older age groups).Table 1.Demographic and clinical characteristicsVariablePsA (n=291)Controls(n=38 955)p-valueAge (years), mean (±SD)58 (12)53 (17)p<0.001Male, n (%)174 (59.8)21 875 (56.2)p =0.21Diabetes, n (%)28 (9.7)1 876 (4.8)p<0.001Cardiovascular disease, n (%)11 (3.8)1 349 (3.5)p=0.77Lung disease, n (%)45 (15.5)4 904 (12.6)p=0.14Cancer, n (%)29 (10.0)2 746 (7.1)p=0.053Alcohol (once a week/more), n (%)71 (24.4)8 234 (21.1)p=0.18Smoking (present/former), n (%)208 (71.5)20 915 (53.7)p<0.001Education (college or higher), n (%)164 (56.4)25 166 (64.6)p=0.003Height (cm), mean (±SD)171 (9.1)171 (9.2)p=0.31Weight (kg), mean (±SD)83 (16.5)79 (15.7)p<0.001Body mass index (kg/m2), mean (±SD)28.3 (4.7)26.9 (4.5)p<0.001Percentage body fat, mean (±SD)33.7 (8.8)30.5(9.3)p<0.001Visceral fat mass (kg), mean (±SD)13.5 (5.5)11.4 (5.4)p<0.001Physical activityp=0.004 Low139 (47.8)16 648 (42.8) Moderate104 (35.7)14 491 (37.2) High48 (16.5)7 816 (20.1)The associations between PA and VFM or PBF were similar with and without PsA. In Model 1 (R2=0.17), moderate or high physical activity was significantly associated with lower VFM. The moderate activity group had 0.8 kg (0.7, 0.9 kg, p<0.001) and the high activity group had 2.6 kg (2.5, 2.7, p<0.001) lower VFM compared to the low physical activity group. In Model 2 (R2=0.38), moderate or high physical activity was significantly associated with lower PBF. The moderate activity group had 1.4% (1.2, 1.5%, p<0.001) and the high activity group had 4.3% (4.1, 4.5%, p<0.001) lower PBF compared to the low physical activity group.ConclusionPatients with PsA had increased PBF and VFM, and moderate or high physical activity was associated with significant reductions in both endpoints. Physical activity may reduce the comorbidity burden among persons with PsA and should be a focus in clinical treatment plans.