Practical consequences of the validation of a mathematical model in assessment of partial androgen deficiency in the aging male using bioavailable testosterone

Partial androgen deficiency or the andropause in the aging male is a complex clinical and biochemical entity that needs to be analyzed at two levels of the constituent structure: the 'deep structure' should come to light with more intensive research, while the 'surface structure' holds the attention of investigators who focus on hormone measurements in the blood to help diagnose the andropause. In this study, it is recognized that bioavailable testosterone decreases progressively during the aging process. This physiological decline may be so important, or so close to castration levels, that aged men may experience numerous symptoms of hypogonadism. The assay for bioavailable testosterone was indirectly validated with a set of equations derived from our knowledge of the law of mass action at equilibrium, as proposed by Vermeulen and colleagues in 1999. With this mathematical model, we have shown that calculated free testosterone was highly correlated with bioavailable testosterone. It is therefore concluded that the evaluation of aged men's androgenicity should rely on at least one of these free testosterone assessments (bioavailable or calculated free testosterone) for the sake of reproducibility in the construction of the 'surface structure' of the andropause in the coming years.     

Low skeletal muscle mass index is associated with function and nutritional status in residents in a Turkish nursing home

Introduction: To determine the prevalence of low muscle mass (LMM) and the relationship between LMM with functional and nutritional status as defined using the LMM evaluation method of European Working Group on Sarcopenia in Older People (EWGSOP) criteria among male residents in a nursing home.

Methods: Male residents aged?>60 years of a nursing home located in Turkey were included in our study. Their body mass index (BMI) kg/m², skeletal muscle mass (SMM-kg) and skeletal muscle mass index (SMMI-kg/m²) were calculated. The participants were regarded as having low SMMI if they had SMMI?<9.2?kg/m² according to our population specific cut-off point. Functional status was evaluated with Katz activities of daily living (ADL) and Lawton Instrumental Activities of Daily Living (IADL). Nutritional assessment was performed using the Mini Nutritional Assessment (MNA). The number of drugs taken and chronic diseases were recorded.

Results: One hundred fifty-seven male residents were enrolled into the study. Their mean age was 73.1?±?6.7 years with mean ADL score of 8.9?±?2.0 and IADL score of 8.7?±?4.6. One hundred twelve (71%) residents were aged?>70 years. Thirty-five men (23%) had low SMMI in group aged?>60 years, and twenty-eight subjects (25%) in the group aged?>70 years. MNA scores were significantly lower in residents with low SMMI compared with having normal SMMI (17.1?±?3.4 versus 19.6?±?2.5, p?=?0.005). BMI was significantly lower in the residents with low SMMI compared with normal SMMI (19.6?±?2.7 versus 27.1?±?4.1, p70 years (8.1?±?2.6 versus 9.1?±?1.6, p?=?0.014). In regression analyses, the only factor associated with better functional status was the lower age (p?=?0.04) while the only factor associated with better nutrition was higher SMMI (p?=?0.01).

Conclusions: Low SMMI detected by LMM evaluation method of EWGSOP criteria is prevalent among male nursing home residents. There is association of low SMMI with nutritional status and probably with functional status within the nursing home setting using the EWGSOP criteria with Turkish normative reference cut-off value.