Analysis of cardiovascular risk factors associated with serum testosterone levels according to the US 2011–2012 National Health and Nutrition Examination Survey

Objective: To investigate associations between cardiovascular disease risk factors, including fasting glucose, cholesterol, high density lipoprotein cholesterol (HDL-c), LDL-c, blood pressure, body mass index (BMI), C-peptide, creatinine kinase, smoking, alcohol use, physical activity, C-reactive protein as well as homocysteine levels and cardiovascular events.

Methods: Data from 1545 men aged ≥40?years, with testosterone deficiency (TD) (<300?ng/dL) and non-TD (≥300?ng/dL) which were extracted from the National Health and Nutrition Examination Survey database 2011–2012 and analyzed.

Results: Multivariate logistic regression analysis showed positive associations between TD and BMI (≥35 vs.?p?=?.016), HDL-c (<0.91 vs. ≥0.91: OR?=?1.60, 95% CI: 1.14–2.24, p?=?.006) and diabetes (diabetes vs. non-diabetes: OR?=?1.48, 95% CI: 1.14–1.92, p?=?.004) as well as negative associations between TD and metabolic equivalent scores (≥12 vs. <12: OR?=?0.69, 95% CI: 0.52–0.91, p?=?.009) and smoking (Ever vs. never: OR?=?0.69, 95% CI: 0.51–0.94, p?=?.018). Furthermore, total serum testosterone levels were lower in patients with heart failure (p?=?.04) and angina/angina pectoris (p?=?.001) compared with subjects without these cardiac problems.

Conclusion: Low serum testosterone was associated with multiple risk factors for CHD.     

Prevalence analysis of urinary incontinence after radical prostatectomy and influential preoperative factors in a single institution

Aims: To assess prevalence of urinary incontinence (UI) after radical prostatectomy (RP) and to analyze which preoperative characteristics of the patients have influence on UI.

Methods: Between 2002 and 2012, 746 consecutive patients underwent RP for clinically localized prostate cancer. We defined UI according to International Continence Society (ICS) definition: “the complaint of any involuntary leakage of urine” after 12?months of recovery, international consultation on incontinence questionnaire (ICIQ-SF) and pads/day was collected too. Clinical features and magnetic resonance imaging measurements were assessed. A multivariable logistic regression model predicting incontinence were built-in after adjust by cofounding factors and bootstrapping.

Results: About 172 (23%) of the patients were classified as incontinent according to the ICS definition. The mean value of the ICIQ-SF was 10.87 (±4). 17.8% of patients use at least one pad/day, 11.9% use more than one pad/day. The preoperative factors independently influential in UI are: age [OR: 1.055; CI 95% (1.006–1.107), p?=?.028], urethral wall thickness [OR: 5.03; CI 95% (1.11–22.8), p?=?.036], history of transurethral resection of the prostate [OR: 6.13; CI 95% (1.86–20.18), p?=?.003] and membranous urethral length [OR: 0.173; CI 95% (0.046–0.64), p?=?.009]. The predictive accuracy of the model is 78.7% and the area under the curve (AUC) value 71.7%.

Conclusions: Urinary incontinence after radical prostatectomy has different prevalence depending on the definition. Age, prior transurethral resection of the prostate (TURP), membranous urethral length (MUL) and urethral wall thickness (UWT) were risk factors.     

Low glomerular filtration rate as an associated risk factor for sarcopenic muscle strength: is creatinine or cystatin C-based estimation more relevant?

Introduction: We aimed to evaluate the association of a decreased glomerular-filtration-rate (GFR?<60?ml/min/1.73?m²), estimated using Modification of Diet in Renal Disease (MDRD), creatinine- and cystatin C-based (CKDEPI-CR and CKDEPI-CC) Chronic Kidney Disease Epidemiology Collaboration equations with handgrip strength (HGS).

Methods: Community-dwelling males aged?≥60 years admitted to outpatient clinic were included. We used MDRD, CKDEPI-CR, and CKDEPI-CC formulas for GFR estimation and corrected these for body surface area. Muscle strength was assessed by HGS.

Results: 209 men (mean age 67.8?±?6.4) were enrolled. Sixty-two patients (29.7%) had sarcopenic HGS. Subjects with sarcopenic HGS were older, had higher rate of a GFR?2, had lower mid-upper arm circumference; tended to have lower creatine kinase, albumin, CKDEPI-CC-GFR levels; and higher BUN/creatinine ratio and cystatin C. Multivariate logistic regression analysis revealed a CKDEPI-CC lower than 60?ml/min/1.73 m² as the only independent factor underlying sarcopenic HGS. Higher age tended to have an independent association. Only higher age was independently associated with low HGS when other estimations were used (p?=?0.013 and p?=?0.021 when MDRD and CKDEPI-CR were used, respectively).

Conclusions: There is a strong association of a GFR level of <60?ml/min/1.73 m² with sarcopenic HGS, when CKDEPI-CC formula is used.     

Association between serum levels of testosterone and biomarkers of subclinical atherosclerosis

Objective: To investigate the association between serum levels of testosterone and biomarkers of subclinical atherosclerosis based on data from 119 middle-aged men of the general population.

Methods: Testosterone, Apolipoprotein A-1 (ApoA-1), Apolipoprotein B (ApoB), Apolipoprotein B-to-Apolipoprotein A-1 ratio (ApoB-to-ApoA-1), high-sensitive C-reactive protein (hsCRP), and fibrinogen levels were measured. Data were also gathered based on age, BMI, waist circumference, smoking, alcohol consumption, and family history of cardiovascular diseases. Men were classified into two groups based on testosterone levels: hypogonadal (testosterone ≤12?nmol/L) and eugonadal men (testosterone >12?nmol/L).

Results: When compared to eugonadal, the hypogonadal men were significantly older (56?years vs. 55?years, p?=?.03), had greater BMI (28?kg/cm² vs. 26?kg/cm², p?=?.01), and higher waist circumference (104?cm vs. 100?cm, p?=?.01). Moreover, ApoB, ApoB-to-ApoA-1 ratio, and hsCRP were significantly higher in hypogonadal men compared to eugonadal men (1.1?g/L vs. 1.0?g/L, p?=?.03), (0.8 vs. 0.7, p?=?.03), (3.3?mg/L vs. 2.0?mg/L, p?=?.01), respectively. On the other hand, ApoA-1 and fibrinogen levels did not differ significantly between groups (p?>?.05). In an adjusted multivariate regression analysis model, only ApoB showed a significant negative association with testosterone levels (β?=??0.01; 95% CI?=??0.02, ?1.50; p?=?.04).

Conclusion: Testosterone levels showed an inverse relation to ApoB, a biomarker implicated in subclinical atherosclerosis. These findings support the hypothesis that low testosterone levels play a role in atherosclerosis.     

PI3K pathway and Bcl-2 family. Clinicopathological features in prostate cancer

The phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR pathways and Bcl-2 family play a central role in prostate cancer (PC). The aim was to determine influence in the biochemical progression in PC. To evaluate the association between clinic pathological and immunohistochemical variables, Spearman’s test was performed. Log-rank test and Kaplan–Meier curves were used for survival comparisons. To explore the correlation of the studied immunohistochemical parameters and the established prognostic variables with biochemical progression, univariate and multivariate Cox proportional Hazard regression analyses were performed. Spearman analysis showed correlation between stroma expression and tumor expression of PI3K with biochemical progression (p?=?.009, p?=?.004), respectively, and tumor immunohistochemical score with biochemical progression (p?=?.051). In the multivariate Cox regression model, only PI3K was retained as independent predictors of biochemical progression. In stroma expression, PI3K is (HR 0.172, 95% CI 0.065–0.452, p?=?.000); tumor expression, PI3K is (HR 0.087, 95% CI 0.026–0.293, p?=?.000), and tumor immunohistochemical score (HR 0.382, 95% CI 0.209–0.697 p?=?.002). Our results suggest a role for prostatic expression of PI3K was prognostic markers for PC. PI3K/AKT/mTOR and Bcl-2 family are becoming an important therapeutic target and predictive biomarkers of onset and progression of PC.     

Testosterone is not associated with mortality in older African-American males

Introduction.?Although testosterone and its association with disease progression and mortality is a widely studied topic, no studies have evaluated mortality risks related to testosterone levels in an older African-American population. The mechanisms for known racial differences in mortality risk for certain cancers and cardiovascular risk factors are largely unknown. Elucidating a mortality risk associated with testosterone levels may give insight into the elevated risk for certain diseases in African-Americans.

Methods and results.?Study data were derived from a cohort 622 African-Americans (age 80.05?±?6.4, range 68–102) from Saint Louis, Missouri that includes 190 males (age 79.38?±?6.2, range 70–102). The eligible sample for this report includes 56 of the 190 males (age 78.89?±?6.9, range 70–102) who donated blood at baseline in 1992–1994 and subsequently tested for total testosterone and bioavailable testosterone. Covariates for adjusted analyses were lower body functional limitations, physician visits and comorbidities, also collected at baseline. Males' mean bioavailable testosterone levels (ng/dl) were 33.33?±?24.4 (n above 70?ng/dl?=?5) and mean total testosterone levels (ng/dl) were 246.63?±?118.7 (n above 300?ng/dl?=?20). Vital status was determined through 2002; 41 males (73%) were deceased and 15 were alive. Mortality did not differ among males with testosterone levels?<300 versus 300+ (p?=?0.42) or with bioavailable testosterone levels?<70 versus > 70 (p?=?0.34). Total testosterone levels did not predict mortality when adjusted for age (Adjusted Hazard Ratio [AHR]?=?0.998; 95% confidence interval [CI] 0.995–1.001; p?=?0.28) or adjusted for age and other covariates (AHR?=?0.099; 95% CI 0.996, 1.002; p?=?0.35). Bioavailable testosterone levels did not predict mortality when adjusted for age (AHR?=?0.992; 95% CI .977–1.007; p?=?0.30) or when adjusted for age and other covariates (AHR 0.991; 95% CI .976–1.006; p?=?0.261).

Conclusion.?In older African-American males, total and bioavailable testosterone levels, with and without adjustment for covariates, are not independently associated with mortality risk.     

Effects of testosterone replacement therapy on hypogonadal men with osteopenia or osteoporosis: a subanalysis of a prospective randomized controlled study in Japan (EARTH study)

Objective: We investigated the effects of testosterone replacement therapy (TRT) on bone mineral density (BMD) among hypogonadal men with osteopenia/osteoporosis.

Methods: From our previous EARTH study population, 74 patients with a clinical diagnosis of osteopenia or osteoporosis and hypogonadism were included in this study, as the TRT (n?=?35) and control (n?=?34) groups. The TRT group was administered 250?mg of testosterone enanthate injection every 4 weeks for 12 months. The BMD, waist circumference, body mass index, body fat percentage, and muscle volume were measured at baseline and at 12 months. Blood biochemical data, including total cholesterol, triglycerides, HDL-cholesterol, hemoglobin A1c, and adiponectin values were also evaluated.

Results: At the 12-month visit, BMD significantly increased in both groups. However, comparisons on changes of parameter values from baseline to the 12-month visit between the TRT and control groups were significantly different in BMD (5.0?±?5.0 vs. 3.0?±?3.2; p?=?.0434) and in adiponectin value (?0.90?±?3.33 vs. 0.10?±?2.04; p?=?.0192). There were no significant changes in other parameters.

Conclusions: TRT for 12 months could improve BMD with a decrease in adiponectin levels among hypogonadal men with osteopenia/osteoporosis.     

The association between triglyceride high density lipoprotein cholesterol ratio and benign prostate hyperplasia in non-diabetic patients:a cross-sectional study

Objectives: To assess the association between triglyceride (TG)/high density lipoprotein (HDL) ratio and benign prostate hyperplasia/lower urinary tract symptoms (BPH/LUTS).

Methods: Four hundred patients who were admitted to the Urology Clinic between January and December 2014 with complaints of BPH/LUTS were enrolled in this cross-sectional study. Patients were divided into two groups according to their International Prostate Symptom Score and prostate volume (PV). They were compared in terms of age, body mass index (BMI), PV, PSA, post micturional residual volume, uroflowmetry Q max value, fasting blood sugar, TG and high density lipoprotein-cholesterol (HDL-C) level and TG/HDL ratio.

Results: Although univariate analyses reveal that age, BMI, waist circumference (WC), FBS, TG, HDL-C level, and TG/HDL ratio were correlated with PV, only age [1.125 OR (1.088–1.164), p?=?.00001], BMI [1.119 OR (1.040–1.204), p?=?.003], TG [(1.043 OR (1.016–1.071), p?=?.002], HDL-C [(0.923 OR (0.860–0.990), p?=?.025], and TG/HDL ratio [(1.224 OR (1.130–1.315), p?=?.014] were statistically significant in multivariate analysis. The calculated area under the curve (AUC) for PV of 30?ml, 40?ml, and 50?ml was 0.668 (0.608–0.727), 0.617 (0.561–0.673), and 0.592 (0.530–0.654), respectively.

Conclusions: Our results indicate that the TG/HDL ratio correlates with enhancement in PV. Further studies are warranted to better evaluate this relationship.     

The impact of testosterone replacement therapy on glycemic control,vascular function,and components of the metabolic syndrome in obese hypogonadal men with type 2 diabetes

Objective: This study set out to assess effects of testosterone replacement therapy (TRT) on parameters of metabolic syndrome and vascular function in obese hypogonadal males with type 2 diabetes mellitus (DM2).

Study design: Fifty-five obese hypogonadal diabetic males on oral hypoglycemic treatment were enrolled into this one-year, double-blind, randomized, placebo-controlled clinical study. Group T (n?=?28) was treated with testosterone undecanoate (1000?mg i.m. every 10?weeks) while group P (n?=?27) received placebo.

Methods: Anthropometrical and vascular measurements – flow-mediated dilatation (FMD) and intima media thickness (IMT) – biochemical and hormonal blood sample analyses were performed at the start of the study and after one year. Derived parameters (BMI, HOMA-IR, calculated free testosterone (cFT) and bioavailable testosterone (BT)) were calculated.

Results: TRT resulted in reduction of HOMA-IR by 4.64?±?4.25 (p?p?p?=?.005).

Conclusion: TRT normalized serum testosterone levels, improved glycemic control and endothelial function while exerting no ill effects on the study population.     

Dutasteride improves bone mineral density in male patients with lower urinary tract symptoms and prostatic enlargement: a preliminary study

Introduction: We studied the effect of dutasteride on bone mineral density (BMD) in aging male patients with lower urinary tract symptoms (LUTS) and prostatic enlargement.

Methods: We prospectively studied 17 patients with LUTS and prostatic enlargement. Before and 1 year after dutasteride (0.5?mg daily), we assessed International Prostate Symptom Score (IPSS), prostatic volume (PV), serum prostatic-specific antigen (PSA) and testosterone. BMD in the lumbar and femur was measured by DEXA method.

Results: Dutasteride significantly reduced PV (from 51?±?24 to 34?±?17?ml, p?p?p?2, p?2, p?2, p?Conclusions: Dutasteride has a potential to improve BMD with elevation of serum testosterone in aging male patients with LUTS and prostatic enlargement.     

Effects of heart rate reduction with ivabradine on the international ındex of erectile function (IIEF-5) in patients with heart failure

Introduction: The presence of concomitant erectile dysfunction (ED) with heart failure (HF) is not surprising, because endothelial dysfunction is pathophysiologic signature of both ED and HF. ED significantly and adversely affects quality of life in patients with HF. It was demonstrated that ivabradine treatment can improve endothelial function and ED in experimental models. In this study, we aimed to determine the effect of ivabradine treatment on ED in patients with HF via International Index of Erectile Function (IIEF-5) questionaire.

Material and methods: Consequently, 29 patients, between 18 and 70?years of age, male with chronic HF known for at least 1?year, New York Heart Association functional class I–II, left ventricule ejection fraction less than 40%, in sinus rhythm with a resting HR of at least 70 beats per minute (b.p.m.), who were intended to be treated with ivabradine according to the decision of their physicians were evaluated to determine ED. We used the Turkish version of the IIEF-5 questionnaire to evaluate ED on the last 6-month period. Twenty-four of 29 patients who scored ≤21 were considered to have ED and included to the study. IIEF-5 scores for each question and domains were calculated for all responders at baseline and at 6-month follow-up visit in order to determine any effect of ivabradine treatment on ED in patients with HF.

Results: According to the data of survey, Cronbach's alpha coeffient for all of the patients who were included into the study were 0.84 and detected highly reliable. IEFF-5 questionnaire scores increased significantly (p?=?.003) after the ivabradine treatment, on the contrary, significant decrease in HR was revealed as expected. HR is decreased steadily after ivabradine treatment and mean decrease in HR was 11.5?±?9.4 in this study population. Likewise, negative correlation was demonstrated between decrease in HR (p?p?=?.003).

Conclusion: Although lack of patients with HF have been evaluated in this study population, initial results seem promising that ivabradine has favorable effects on ED. These findings were postulated to be dependent exclusively on HR reduction. As a sequel, cardiologist should avoid neglecting ED to improve medical compliance as well as quality of life in patients with heart failure. This pilot study provide some data for further randomized controlled studies.     

No association of serum PSA with vitamin D or total oxidant-antioxidant capacity in healthy men

Background and aim: Vitamin D deficiency and oxidative stress were suggested to be related to prostate cancer risk. We aimed to investigate the association of serum PSA concentration with vitamin D and total oxidant/antioxidant levels.

Materials and methods: A total of 95 healthy men were enrolled for the cross sectional study. Serum PSA, 25(OH)D, serum total oxidant status, and total antioxidant status were measured.

Results: Serum PSA was significantly negatively correlated with serum total oxidant status (r=??0.309, p?=?.003) but there was no significant correlation between PSA and 25(OH)D (p?=?.383) or total antioxidant levels (p?=?.233). After adjustment for age BMI and smoking status with multiple regression analysis, there was no significant association between serum PSA and total oxidant status.

Conclusion: We find no evidence for an association between PSA and vitamin D levels or serum total oxidant/antioxidant levels.     

Interleukin-18 and testosterone levels in men with metabolic syndrome

Objective: Interleukin 18 (IL-18) is an adipokine associated with obesity. Data about the relationship of IL-18 to the metabolic syndrome (MS) are still scarce. Low testosterone (T) levels are common in men with MS, but we did not find data about the levels of IL-18 in men with low T. The aim of this study was to determine the levels of IL-18 in men with MS with or without low T.

Patients and methods: A total of 251 men were included in the study. Of them 218 had MS (IDF 2005) and they were divided according to their morning total testosterone (TT) level (cutoff 10.4?nmol/l) into two groups: MS-low T (N?=?84) and MS-normal T (N?=?134). The control group consisted of 33 men without MS and low T. IL-18 was determined in serum using enzyme-linked immunosorbent assay. A small group of eight men with MS and low T levels received testosterone therapy for three months and physical and laboratory parameters were monitored at the end of that period.

Results: MS men were at mean age (±SD)?=?53.77?±?9.59 years; body mass index (BMI)?=?34.0?±?6.3?kg/m²; and TT?=?12.59?±?5.66?nmol/l. The control group was at age?=?52.12?±?5.2 years (NS); BMI?=?25.6?±?2.4?kg/m² (p?p?p?p?p?p?Conclusions: In this study, higher IL-18 levels were found in the presence of MS compared to healthy men, but they did not differ between men having MS with or without LOH.     

Knowledge and perception of female nursing students about human papillomavirus (HPV), cervical cancer,and attitudes toward HPV vaccination

Objective: The researchers aimed to evaluate the knowledge and perceptions of first-year female nursing students about human papillomavirus (HPV), cervical cancer (CC), and HPV vaccination. Participants: The sample included 690 female nursing students from sampled universities between April and June 2015. Methods: Students were surveyed by using a pretested HPV and CC awareness questionnaire. Results: More than half of the students (65.1%) answered questions incorrectly with a mean HPV knowledge score of 6.085?±?3.38. The majority of students (82.6%) did not hear HPV vaccine. Only, 2.8% of the students had been vaccinated. A statistically significant relationship was found between HPV knowledge score and hearing about HPV vaccine (U?=?28280.500, p?=?.015), and believing HPV vaccine protectiveness (χ²?=?14.153, p?=?.001). Conclusions: This study highlights the lack of knowledge and low level of awareness about HPV, CC, and HPV vaccination among first-year nursing college students.     

Visceral adiposity index is associated with benign prostatic enlargement in non-diabetic patients: a cross-sectional study

Objective: To evaluate the association between visceral adiposity index (VAI) - a novel indicator for the assessment of visceral adipose tissue and prostate enlargement in non diabetic patients.

Material and methods: Four hundred patients who were admitted to the Urology clinic between January and December 2014 with complaints of BPH(benign prostatic hyperplasia )/LUTS(male lower urinary tract symptoms)were enrolled in this cross-sectional study. Patients were divided into two groups according to their prostate volume and international prostate symptom score (IPSS) value. They were compared in terms of age, body mass index (BMI), VAI, prostate volume, PSA, post micturional residual volume (PMRV), uroflowmetry Q max value, triglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and fasting blood sugar (FBS).

Results: Although univariate analyses reveal that age, BMI, waist circumference (WC), FBS, TG, HDL-C level and TG/HDL ratio were correlated with prostate volume, only age [1.125 OR (1.088–1.164), p?=?.00001], BMI [1.119 OR (1.040–1.204), p?=?.003], TG [1.043 OR (1.016–1.071), p?=?.002], HDL-C [0.923 OR (0.860–0.990), p?=?.025] and VAI [1.194 OR (1.110–1.305), p?=?.011] were statistically significant in multivariate analysis. A positive correlation was found between VAI value and prostate volume in the Spearman correlation test (r?=?0.29, p?=?.00001). The calculated area under the curve (AUC) for prostate volumes of 30, 40 and 50?ml were 0.680 (0.621–0.738), 0.625 (0.570–0.681) and 0.590 (0.528–0.652), respectively.

Conclusion: Our study revealed a positive correlation between VAI and prostate volume. Our results are needed to be tested with well-designed randomized prospective cohort studies.     

Influence of testosterone substitution on glycemic control and endothelial markers in men with newly diagnosed functional hypogonadism and type 2 diabetes mellitus: a randomized controlled trial

Abstract

Effects of testosterone (T) on the cardiovascular system of men remain controversial. The impact of T-replacement therapy (TRT) in men with functional hypogonadism and type 2 diabetes mellitus (T2DM) has to be elucidated. This study included 80 men (mean age 51.5?±?6.3 years) with newly diagnosed T2DM (according to ADA criteria) and functional hypogonadism (according to EAU criteria). Randomization: Group1 (n?=?40): TRT using 1%-transdermal T-gel (50?mg/day), Group2 (n?=?40) no TRT (controls). Dietary treatment applied to both. Parameters at baseline/after 9?months: anthropometric parameters, lipids and indicators of carbohydrate metabolism (fasting glucose, insulin, HbA1c, HOMA-IR), markers of adipose tissue and EnD (leptin, resistin, p- and e-selectin, ICAM- 1, VCAM- 1 and CRP). ANCOVA for repeated measurements revealed TRT to cause a significant decrease in waist circumference (WC), HOMA-IR and HbA1c vs controls (p?<?.001, p?=?.002, p?=?.004, respectively). Leptin declined in subjects receiving TRT vs controls (p?=?.04). Concentrations of resistin, ICAM-1, p-selectin and CRP decreased significantly vs controls (all p?<?.001); no effects for e-selectin and VCAM-1. Advanced age attenuated effects, higher delta testosterone levels augmented effects. Decrement of WC was related to decreasing markers of adipose tissue secretion/EnD. TRT in men with functional hypogonadism and T2DM improved carbohydrate metabolism and markers of endothelial dysfunction.     

High-intensity interval training (HIIT) increases insulin-like growth factor-I (IGF-I) in sedentary aging men but not masters’ athletes: an observational study

Introduction: The aim of this investigation was to examine the impact high-intensity interval training (HIIT) on serum insulin-like growth factor-I (IGF-I) in active compared with sedentary aging men.

Methods: 22 lifetime sedentary (SED; 62?±?2 years) and 17 masters’ athletes (LEX; 60?±?5 years) were recruited to the study. As HIIT requires preconditioning exercise in sedentary cohorts, the study required three assessment phases; enrollment (phase A), following preconditioning exercise (phase B), and post-HIIT (phase C). Serum IGF-I was determined by electrochemiluminescent immunoassay.

Results: IGF-I was higher in LEX compared to SED at baseline (p?=?0.007, Cohen’s d?=?0.91), and phase B (p?=?0.083, Cohen’s d?=?0.59), with only a small difference at C (p?=?0.291, Cohen’s d?=?0.35). SED experienced a small increase in IGF-I following preconditioning from 13.1?±?4.7 to 14.2?±?6.0?μg·dl^?1 (p?=?0.376, Cohen’s d?=?0.22), followed by a larger increase post-HIIT (16.9?±?4.4?μg·dl^?1), which was significantly elevated compared with baseline (p?=?0.002, Cohen’s d?=?0.85), and post-preconditioning (p?=?0.005, Cohen’s d?=?0.51). LEX experienced a trivial changes in IGF-I from A to B (18.2?±?6.4 to 17.2?±?3.7?μg·dl^?1 [p?=?0.538, Cohen’s d?=?0.19]), and a small change post-HIIT (18.4?±?4.1?μg·dl^?1 [p?=?0.283, Cohen’s d?=?0.31]). Small increases were observed in fat-free mass in both groups following HIIT (p?d?=?0.32–0.45).

Conclusions: In conclusion, HIIT with preconditioning exercise abrogates the age associated difference in IGF-I between SED and LEX, and induces small improvements in fat-free mass in both SED and LEX.     

Application of multivariate longitudinal models in SIRT6, FBS,and BMI analysis of the elderly

Abstract

Objective: SIRT6 is a main regulator of metabolism and lifespan and its importance has been implicated in the prevention against aging-related diseases. The objective of this study was to examine the application of multivariate longitudinal models in SIRT6, FBS, and BMI analysis in the elderly men after eight weeks concurrent training with supplementation of l-arginine (l-Arg).

Methods: Thirty two elderly men with mean age of 63.09?±?3.71 years were randomly divided into four equal-sized groups (each n?=?8); Exercise?+?supplement (ES) group; exercise?+?placebo (EP) group; supplement (S) group and control (C) group. The ES and EP groups performed the eight weeks of concurrent training, three sessions per week. Group ES and group S consumed 1000?mg of l-Arg per day at 8:00?pm. Measurements of biochemical variables were done by ELISA Reader method. For analytical purposes, we used the paired sample t-test and multivariate longitudinal modeling with generalized estimating equation (GEE) methodology. All analyses have been implemented in R-3.4.1. p Values less than .05 were considered statistically significant.

Results: With respect to significant association between sirt6, FBS, and BMI, this study showed that synergy effect of training and supplementation was greater than the sum of their individual effects on SIRT6 (β?=?0.79, p?<?.001), FBS (β?=??5.56, p?=?.022), and BMI (β?=??3.89; p?=?.041). Also exercise alone had a significantly larger effect than supplementation alone on responses.

Conclusions: It can be concluded that the joint usage of concurrent training and supplement of l-Arg for elderly men could improve the metabolism and body composition.