(090) The Relationship Between C-Reactive Protein and Total Testosterone in Aging Men: Findings from the Baltimore Longitudinal Study of Aging

Abstract

Abstract Introduction Elevated C-Reactive Protein (CRP) and testosterone deficiency are associated with advanced age and chronic inflammatory diseases, such as cancer, diabetes, and cardiovascular disease. Testosterone decreases inflammation through several mechanisms, and testosterone replacement therapy (TRT) has been shown to lower CRP levels in aging, hypogonadal men. While cross-sectional studies have shown an inverse relationship between CRP and total testosterone (TT) levels, mixed findings have been reported when individual components of metabolic syndrome are considered. We hypothesized that men with testosterone deficiency will have high levels of CRP. Objective We evaluated the relationship between CRP and TT levels in men from 2004-2018 using the Baltimore Longitudinal Study of Aging and specifically attempted to determine if low androgen status is associated with a high inflammatory profile independent of comorbidities. Methods Male participants with serum TT level measured during two separate visits >3 years apart were included in our cohort. CRP, High-Density Lipoprotein (HDL) and Triglyceride levels were collected via blood specimens. Comorbidity data were documented at each visit. Panel regression was used to analyze the relationship of a series of independent variables collected in pooled cross-sectional observations over time with a dependent variable for modeling. Results A total of 347 patients were included in this study (mean age = 69 ± 15, average follow up time = 6.7 ± 3.2 years). Participants had a median CRP level of 1.0 mg/dL and a median TT level of 446 ng/dL. On univariable analysis TT and HDL levels were associated with a decline in CRP, while BMI, congestive heart failure (CHF), Diabetes, and Triglycerides were associated with increased CRP. Age was not associated with CRP. On multivariable analysis, we found that increasing TT level was associated with a decline in CRP levels, independent of comorbidities (p = 0.018; Table 1). BMI was associated with a significant increase in CRP (p = 0.001, Table 1). Age, CHF, Diabetes, HDL, and Triglycerides were not significant predictors of CRP on multivariable analysis. Conclusions Lower levels of serum total testosterone are associated with an increased CRP in older men. Given the importance of CRP in pathogenesis of chronic disease, we highlight the potential benefits of restoring testosterone levels in older, hypogonadal men via TRT. Disclosure No.