Factors influencing serum concentrations of soluble interleukin-2 receptor: a general adult population study

Abstract

Introduction: Measuring soluble interleukin-2 receptor (sIL-2R) might be useful for diagnosis and monitoring of immune-mediated diseases. The study investigated factors associated with serum sIL-2R concentrations in adults.

Methods: Serum sIL-2R concentrations were measured in 1499 randomly selected individuals (44.6% male, median age 52 years, range 18–91 years). Lifestyle factors (alcohol consumption, smoking, and physical activity) were assessed by questionnaire. Body mass index and data defining metabolic syndrome were measured in all participants. Atopy was defined by skin tests to aeroallergens.

Results: Serum sIL-2R concentrations displayed wide variation (2.5–97.5 percentile range, 209–950 U/mL). A total of 230 (15.3%) individuals showed values higher than the standard reference range (158–623 U/mL). After adjusting for covariates, sIL-2R concentrations increased with age, particularly after 65 years. Serum sIL-2R concentrations were higher in males than in females, were higher in smokers than in never smokers, and were higher in atopic than in non-atopic individuals. Serum sIL-2R concentrations were positively associated with metabolic syndrome, particularly with abdominal obesity, and with a history of ischemic heart disease. Light alcohol drinkers showed lower sIL-2R concentrations than abstainers.

Conclusion: Aging, sex, lifestyle factors, atopy, metabolic abnormalities, and ischemic heart disease might influence serum sIL-2R concentrations in adults.

KEYWORDS:

• interleukin-2 receptor
• age
• alcohol
• smoking
• metabolic syndrome
• atopy

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Arturo Gonzalez-Quintela and Francisco Gude were responsible for conception and design. Francisco Gude and Manuela Alonso-Sampedro performed the analysis and interpretation of the data. Carmen Fernández-Merino, Bernardo Sopeña, and Vanessa Alende-Castro were involved in the patient management and data collection. Vanessa Alende-Castro, Carmen Vidal and Arturo Gonzalez-Quintela drafted the paper. All authors approved the version to be published and agree to be accountable for all aspects of the work.

Data availability statement

Due to the nature of this research, participants of this study did not agree for their data to be shared publicly, so supporting data is not available.

Additional information

Funding

The study was supported by grants from the Carlos III Institute of Health  (Instituto de Salud Carlos III, PI16/01404 and PI16/01395), the Spanish Network for Additive Disorders (Red de Trastornos Adictivos, RD16/0017/0018, Spanish Ministry of Health), the Spanish Network for Preventive Activity and Health Promotion Research in Primary Care (Red de Actividades Preventivas y de Promocion de Salud en Atención Primaria, RD16/0007/0006), and the European Regional Development Fund (ERDF).