The association of systemic low-grade inflammation with health-related quality of life in Finnish young men

Abstract

Background During the last two decades, it has become evident that inflammatory mechanisms have central role in pathological processes of several chronic diseases such as type 2 diabetes, cardiovascular disease, stroke, tumorigenesis, chronic obstructive pulmonary disease, and Alzheimer disease. Chronic diseases tend to lower health-related quality of life (HRQoL). Low HRQoL has been associated with increased mortality risk. Several factors like age, gender, body mass index, smoking, cardiovascular fitness, and morbidities have been associated both inflammatory markers and HRQoL. There is a data that HRQoL has been associated inversely with inflammatory markers, but the data is very limited in healthy, young, adult population.

Objective To investigate associations between HRQoL and systemic low-grade inflammation in a Finnish young, men population.

Material and Methods Participants (n = 777; mean age 26.5 SD 6.8 years) were volunteered male reservists of the Finnish Defence Forces who participated in refresher courses organized in seven different garrisons around Finland during 2015. As a measure of HRQoL physical (PCS) and mental (MCS) component summary scores of the RAND-36 were calculated. Plasma concentrations of C-reactive protein (CRP) and Interleukin-6 (IL-6) were analyzed from the blood samples of participants. Cardiorespiratory fitness and muscle strength and fitness of the participants were measured. Correlation and regression analysis were performed, and in regression analysis there were also adjustments for age, BMI and smoking-status.

Results The means (SD) for CRP, IL-6, PCS, and MCS were 1.15 mg/L (1.54), 1.10 pg/L (1.35), 54.8 (4.6), and 50.9 (9.4), respectively. Mean VO2max (ml · kg-1· min-1) of the participants was 41.3 SD 7.7. There were statistically significant association between PCS and both inflammatory markers (modified to natural logarithmic values), but not between MCS and inflammatory markers. Cardiorespiratory and muscle fitness were associated positively with PCS and negatively with inflammatory markers. In regression analysis after adjustments for age, BMI, and smoking-status, there were weak but significant association between both PCS and MCS and inflammatory markers.

Conclusion The present study shows that there is a relationship between PCS of the RAND-36 and inflammatory markers in a healthy, resilient, young, adult men population, despite both CRP and IL-6 explained only a little about the variance of PCS.