Evaluation of Nutritional Status and Methods to Identify Nutritional Risk in Rheumatoid Arthritis and Spondyl arthritis  
[PERSON]  
1 Mohn Nutrition Research Laboratory, Department of Clinical Medicine, Faculty of Medicine, University of Bergen, P.O. Box 7804, 5020 Bergen, Norway; [EMAIL_ADDRESS]  
[PERSON]  
1 Mohn Nutrition Research Laboratory, Department of Clinical Medicine, Faculty of Medicine, University of Bergen, P.O. Box 7804, 5020 Bergen, Norway; [EMAIL_ADDRESS]  
[PERSON]  
2 Department of Rheumatology, Haukeland University Hospital, 5021 Bergen, Norway; [PERSON]f Research and Development, Haukeland University Hospital, P.O. Box 1400, 5021 Bergen, Norway  
4 Department of Clinical Science, Faculty of Medicine, University of Bergen, P.O. Box 7804, 5020 Bergen, Norway  
4 Correspondence: [EMAIL_ADDRESS]; Tel. : +47-9580240  
Patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA) are prone to develop malnutrition as their medication often affects appetite, nutrient absorption, and digestion [7; 8; 9; 10; 11]. Due to joint pain and fatigue, patients can experience challenges in food shopping and preparation [8; 12]. In addition, the increased level of inflammation may increase nutritional needs [13]. Nutritional status is commonly assessed by body mass index (BMI; kg/m\({}^{2}\)) in a clinical setting [14]. However, reduced fat-free mass (FFM) and increased fat mass (FM) have been reported in rheumatic patients, due to cytokine-driven hyper-metabolism and decreased activity levels [15]. Rheumatoid cachexia (RC) is a term used to describe this phenomenon [16]. An increase in FM often masks a reduction in FFM, which results in no change in BMI. Measurement of body composition (fat-free mass index (FFMI; kg/m\({}^{2}\)) and fat mass index (FMI; kg/m\({}^{2}\))) provides more precise information, and dual energy X-ray absorptiometry (DXA) is considered the gold standard for this purpose [14]. FFMI and FMI are conceptually similar to BMI (BMI = FFMI + FMI). There is no clear consensus on the cut-off levels used to define RC, but FFMI <10 th percentile and FMI >25 th percentile have been proposed [17]. Although new drugs have revolutionized treatment, some patients still suffer from pain, stiffness, or fatigue, or experience side effects of their drugs. Patients with rheumatic diseases are therefore likely to experiment with \"dietary therapies\" as a complementary treatment. However, the scientific evidence regarding the effect of specific diets on RA and SpA is limited [18; 19]. It is a cause for concern that dietary therapies, leading to restrictions that are not based on scientific evidence, can lead to reduced intake of food or nutrients [20]. As treatment of inflammatory rheumatic diseases in hospitals increasingly takes place in outpatient clinics, it is necessary to validate the nutritional screening tools and guidelines for this purpose. To our knowledge, no such guidelines exist for patients with RA or SpA [21]. Further, it is unclear to what extent Nutritional Risk Screening 2002 (NRS2002) identifies nutritional risk in this patient group [22; 23]. It is worrying that little attention is given to these patients' dietary intake and nutritional status [24; 25]. The Global Leadership Initiative on Malnutrition (GLIM) has developed a two-step approach for diagnosing malnutrition: (i) a nutritional risk screening using a validated screening tool (e.g., NRS2002) and (ii) a diagnostic assessment that considers both phenotypic and etiological aspects of malnutrition [26]. It is unclear whether these criteria are appropriate to identify malnutrition in patients with RA and SpA. The majority of previous studies addressing nutrition and rheumatic disease have applied to patients with RA, while studies on SpA are rare [19]. Therefore, this study aimed to evaluate nutritional status and dietary habits in outpatients with RA and SpA in order to describe nutritional challenges for these patients.