Are soluble ST2 levels influenced by vitamin D and/or the seasons?

• Main Authors: Vito Francic, Martin Keppel, Verena Schwetz, Christian Trummer, Marlene Pandis, Valentin Borzan, Martin R Grübler, Nicolas D Verheyen, Marcus E Kleber, Graciela Delgado, Angela P Moissl, Benjamin Dieplinger, Winfried März, Andreas Tomaschitz, Stefan Pilz, Barbara Obermayer-Pietsch
• Format: Article
• Language: English
• Published: Bioscientifica 2019-05-01
• Series: Endocrine Connections
• Subjects: soluble ST2; seasonality; vitamin D; biomarker; cardiovascular disease
• Online Access: https://ec.bioscientifica.com/view/journals/ec/8/6/EC-19-0090.xml

Objective: Cardiovascular disease manifestation and several associated surrogate markers, such as vitamin D, have shown substantial seasonal variation. A promising cardiovascular biomarker, soluble ST2 (sST2), has not been investigated in this regard – we therefore determined if systemic levels of sST2 are affected by seasonality and/or vitamin D in order to investigate their clinical interrelation and usability. Design: sST2 levels were measured in two cohorts involving hypertensive patients at cardiovascular risk, the Styrian Vitamin D Hypertension Trial (study A; RCT design, 8 weeks 2800 IU cholecalciferol daily) and the Ludwigshafen Risk and Cardiovascular Health Study (LURIC; study B; cross-sectional design). Methods: The effects of a vitamin D intervention on sST2 levels were determined in study A using ANCOVA, while seasonality of sST2 levels was determined in study B using ANOVA. Results: The concentrations of sST2 remained unchanged by a vitamin D intervention in study A, with a mean treatment effect (95% confidence interval) of 0.1 (−0.6 to 0.8) ng/mL; P = 0.761), despite a rise in 25(OH)D (11.3 (9.2–13.5) ng/mL; P < 0.001) compared to placebo. In study B, seasonal variations were present in 25(OH)D levels in men and women with or without heart failure (P < 0.001 for all subgroups), while sST2 levels remained unaffected by the seasons in all subgroups. Conclusions: Our study provides the first evidence that systemic sST2 levels are not interrelated with vitamin D levels or influenced by the seasons in subjects at cardiovascular risk.