Hand-Grip Strength Is Associated With Serum Testosterone and Albumin Levels in Male Kidney Transplant Recipients

Abstract

Objectives: In kidney transplant recipients, reduced muscle mass and hand-grip strength are associated with impaired nutritional status. Serum testosterone is highly associated with muscle strength in the general population. Here, we aimed to determine the associations among serum testosterone, hand-grip strength, and nutritional and inflammatory parameters, as well as graft function.

Materials and Methods: Our study included 144 stable male kidney transplant recipients from our renal transplant outpatient clinic. All patients were evaluated for clinical parameters (age, duration of hemodialysis, and posttransplant time), biochemical parameters (calcium, phosphorus, parathyroid hormone, C-reactive protein, albumin, creatinine), and serum testosterone levels. Body composition was analyzed with the bioimpedance spectroscopy analysis technique using a body composition monitor that estimates body mass index and percent fat. Hand-grip strength was analyzed by using a dynamometer (ProHealthcareProducts.com, Park City, UT, USA). We calculated estimated glomerular filtration rate using the Modification of Diet in Renal Disease-4 equation.

Results: Demographic characteristics, duration of dialysis before transplant, biochemical parameters, and estimated glomerular filtration rates were similar among study patients. Mean (standard deviation) serum testosterone was 588.0 (55.5) ng/dL, mean body mass index was 26.8 (0.6) kg/m(2), and mean hand-grip strength was 42.2 (1.7) mm(2). Serum testosterone levels were positively correlated with hand-grip strength (r = 0.445; P = .033) and serum albumin (r = 0.399; P = .05) and negatively correlated with serum C-reactive protein (r = -0.454;P= .05) and age. In linear multiple regression analysis, serum albumin (P= .033) and testosterone levels (P = .038) were shown to be predictors of hand-grip strength. However, we could not show a significant correlation between graft function and testosterone.

Conclusions: Serum testosterone level is correlated with hand-grip strength and C-reactive protein and albumin levels, which may indicate that testosterone affects nutritional status and inflammation in male renal transplant recipients.