Sociodemographic Factors, Nutritional Status, and Inflammatory Markers in Patients with Postural Orthostatic Tachycardia Syndrome

Objectives. Postural orthostatic tachycardia syndrome (POTS) is characterized by cardiovascular autonomic dysfunction of unknown etiology with high a prevalence of gastrointestinal symptoms. The aim of the present study was to examine sociodemographic, lifestyle, and nutritional factors as well as inflammatory markers in patients with POTS. Materials and Methods. Forty-three patients with POTS and 61 healthy controls completed questionnaires about sociodemographic factors, lifestyle habits, and gastrointestinal symptoms. Blood samples were analyzed for serum levels of cobalamins, folic acid, iron, total iron-binding capacity (TIBC), ferritin, sodium, potassium, magnesium, phosphorus, albumin, high-sensitive C-reactive protein (CRP), and 25-hydroxyvitamin D (25-OH vitamin D). Results. POTS patients were predominantly women with a lower education level and were more often working part-time, on sick leave, and living alone compared with healthy controls. They reported lower alcohol intake and physical activity levels than controls. The nutrient intake was in general similar in both groups, but POTS patients had a higher intake of different drinks and reported more gastrointestinal symptoms than controls. POTS was associated with higher CRP levels (beta: 1.370; 95% CI: 0.004-2.737; p=0.049), lower albumin levels (beta: -1.443; 95% CI: -2.648-(-0.238); p=0.019), and higher sodium levels (beta: 1.392; 95% CI: 0.559-2.225; p=0.001). Abdominal pain (p=0.004) and intestinal symptoms' influence on daily life (p=0.025) were negatively associated with albumin levels. Abdominal pain (p=0.011), vomiting and nausea (p=0.003), and intestinal symptoms' influence on daily life (p=0.026) were associated with higher sodium levels. Serum levels representing iron and vitamin metabolism were equal between groups. Conclusions. POTS is associated with poorer sociodemographic status, but malnutrition cannot explain POTS or related gastrointestinal symptoms. Higher CRP and lower albumin levels suggest low-grade inflammation as one possible etiological factor.