P4539Android to gynoid fat ratio and its association with functional capacity in male patients with heart failure

Background

Obesity may have a protective role in patients with heart failure with reduced ejection fraction (HFrEF), a phenomenon known as obesity paradox. However, some patients can also present sarcopenic obesity with similar exercise intolerance as lean patients with muscle wasting. However, the impact of body fat distribution on exercise intolerance in HFrEF is unknown.

Purpose

To study the association between android to gynoid fat ratio and functional capacity (VO2 peak) in male patients with HFrEF.

Methods

We enrolled 118 male with HFrEF with left ventricular ejection fraction (LVEF) <40%, mean age of 56±7 years old. Body composition was measured with dual x-ray absorptiometry. Android and gynoid fat were measured and the ratio between them was calculated (A/G ratio). Appendicular lean mass (ALM) was calculated as the lean muscle mass of both arms and legs divided by the height squared. Sarcopenic obesity was defined according to Foundation for the National Institutes of Health criteria (ALM adjusted for body mass index <0.789 for men). Muscle strength was assessed using the handgrip dynamometer (cutoff point for sarcopenia was defined as proposed by European Working Group on Sarcopenia in Older People). Blood sample was used to measure metabolic and hormonal parameters.

Results

Of those 118 patients, 15 (12.7%) showed sarcopenic obesity. In our cohort, the median A/G ratio was 0.55. A/G ratio >0.55 was detected in 60 patients. Weight and BMI were higher in patients with A/G ratio >0.55 (P<0.001). Absolute peak VO2 was similar between patients with A/G ratio lower or higher than 0.55 (1.48±0.40 vs. 1.43±0.40 L/min, P=0.559), while relative peak VO2 was lower in patients with A/G ratio >0.55 (18.7±5.3 vs. 22.5±6.1 mL/kg/min, P<0.001). LVEF, total cholesterol, LDL, haemoglobin, and IGF-1 were similar between patients with A/G ratio lower or higher than 0.55 (P>0.05). On the other hand, HDL, total testosterone, free testosterone, and DHEA were lower in patients with A/G ratio >0.55 (P<0.05). Logistic regression analysis showed A/G Ratio >0.55 to be independently associated with reduced peak VO2 (L/min) adjusted for age, BMI, LVEF, presence of sarcopenia, anabolic hormones, and haemoglobin (odds ratio 3.895, 95% CI 1.030–14.730, p=0.045).

Conclusion

Our data suggest that body fat distribution, particularly android and gynoid fat composition, might have an important adverse role on functional capacity in male patients with HFrEF.

Acknowledgement/Funding

FAPESP #2016/24306-0 and 2016/24833-0

Effect of Exercise Training and Testosterone Replacement on Skeletal Muscle Wasting in Patients With Heart Failure With Testosterone Deficiency

OBJECTIVE

To examine whether combined testosterone replacement and exercise training (ET) therapies would potentiate the beneficial effects of isolated therapies on neurovascular control and muscle wasting in patients with heart failure (HF) with testosterone deficiency.

PATIENTS AND METHODS

From January 10, 2010, through July 25, 2013, 39 male patients with HF, New York Heart Association functional class III, total testosterone level less than 249 ng/dL (to convert to nmol/L, multiply by .03467), and free testosterone level less than 131 pmol/L were randomized to training (4-month cycloergometer training), testosterone (intramuscular injection of testosterone undecylate for 4 months), and training + testosterone groups. Muscle sympathetic nerve activity was measured using microneurography, forearm blood flow using plethysmography, body composition using dual X-ray absorptiometry, and functional capacity using cardiopulmonary test. Skeletal muscle biopsy was performed in the vastus lateralis.

RESULTS

Muscle sympathetic nerve activity decreased in ET groups (training, P<.01; training + testosterone, P<.01), whereas no changes were observed in the testosterone group (P=.89). Forearm blood flow was similar in all groups. Lean mass increased in ET groups (training, P<.01; training + testosterone, P<.01), whereas lean mass decreased in the testosterone group (P<.01). The response of cross-sectional area of type I (P<.01) and type II (P<.05) fibers increased in the training + testosterone group as compared with the isolated testosterone group.

CONCLUSION

Our findings provide evidence for a superior effect of combined ET and testosterone replacement therapies on muscle sympathetic nerve activity, muscle wasting, and functional capacity in patients with HF with testosterone deficiency.

Effects of diet and exercise training on neurovascular control during mental stress in obese women

Since neurovascular control is altered in obese subjects, we hypothesized that weight loss by diet (D) or diet plus exercise training (D + ET) would improve neurovascular control during mental stress in obese women. In a study with a dietary reduction of 600 kcal/day with or without exercise training for 4 months, 53 obese women were subdivided in D (N = 22, 33 +/- 1 years, BMI 34 +/- 1 kg/m2), D + ET (N = 22, 33 +/- 1 years, BMI 33 +/- 1 kg/m2), and nonadherent (NA, N = 9, 35 +/- 2 years, BMI 33 +/- 1 kg/m2) groups. Muscle sympathetic nerve activity (MSNA) was measured by microneurography and forearm blood flow by venous occlusion plethysmography. Mental stress was elicited by a 3-min Stroop color word test. Weight loss was similar between D and D + ET groups (87 +/- 2 vs 79 +/- 2 and 85 +/- 2 vs 76 +/- 2 kg, respectively, P < 0.05) with a significant reduction in MSNA during mental stress (58 +/- 2 vs 50 +/- 2, P = 0.0001, and 59 +/- 3 vs 50 +/- 2 bursts/100 beats, P = 0.0001, respectively), although the magnitude of the response was unchanged. Forearm vascular conductance during mental stress was significantly increased only in D + ET (2.74 +/- 0.22 vs 3.52 +/- 0.19 units, P = 0.02). Weight loss reduces MSNA during mental stress in obese women. The increase in forearm vascular conductance after weight loss provides convincing evidence for D + ET interventions as a nonpharmacologic therapy of human obesity.

Effects of losartan combined with exercise training in spontaneously hypertensive rats

We investigate whether combined treatment with losartan, an angiotensin II receptor blocker, and exercise training (ET) in spontaneously hypertensive rats (SHR) would have an additive effect in reducing hypertension and improving baroreflex sensitivity when compared with losartan alone. Male SHR (8 weeks old) were assigned to 3 groups: sedentary placebo (SP, N = 16), sedentary under losartan treatment (SL, N = 11; 10 mg kg-1 day-1, by gavage), and ET under losartan treatment (TL, N = 10). ET was performed on a treadmill 5 days/week for 60 min at 50% of peak VO2, for 18 weeks. Blood pressure (BP) was measured with a catheter inserted into the carotid artery, and cardiac output with a microprobe placed around the ascending aorta. The baroreflex control of heart rate was assessed by administering increasing doses of phenylephrine and sodium nitroprusside (iv). Losartan significantly reduced mean BP (178 16 vs 132 12 mmHg) and left ventricular hypertrophy (2.9 0.4 vs 2.5 0.2 mg/g), and significantly increased baroreflex bradycardia and tachycardia sensitivity (1.0 0.3 vs 1.7 0.5 and 2.0 0.7 vs 3.2 1.7 bpm/mmHg, respectively) in SL compared with SP. However, losartan combined with ET had no additional effect on BP, baroreflex sensitivity or left ventricular hypertrophy when compared with losartan alone. In conclusion, losartan attenuates hypertension and improves baroreflex sensitivity in SHR. However, ET has no synergistic effect on BP in established hypertension when combined with losartan, at least at the dosage used in this investigation.