Type 2 Diabetes Mellitus Influence on Patients With Heart Failure With Preserved Ejection Fraction in Neuromuscular Fatigue and Exercise Capacity
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 21
- 试验地点
- 1
- 主要终点
- Change of the isometric force
研究概览
简要总结
An important feature of patients with HFpEF is impaired exercise tolerance, resulting in worsening and reduced quality of life. Studies in the literature on patients with HFpEF suggest that the limited transport of oxygen to the muscles can be one factor leading to the early development of fatigue during physical activity and reduced effort tolerance. A recent study also shows that patients with HFpEF have an increased susceptibility to both central and peripheral fatigue, suggesting that neuromuscular fatigue may be one of the main mechanisms limiting exercise in this population.
Type 2 diabetes mellitus (T2DM), which affects 90-95% of diabetic patients, is a comorbidity of particular interest in heart failure (HF). In T2DM, as in HF, some observed an altered energy metabolism of the muscle and a shift in the type of muscle fibers. Hyperglycemia influences neuromuscular function and appeared to be one of the major causes of oxidative stress by affecting the intrinsic properties of the muscle (mitochondrial activity and function, myofilaments) related to the expression of force. The impact of diabetes on neuromuscular function is also linked to long-term complications such as diabetic peripheral neuropathy involving impairment of motor nerve conduction and vascular complications. This opens up a rather complex picture suggesting that T2DM in patients with HF could contribute to a further decline in muscle strength by further reducing the aerobic capacity of these patients.
It seems, there are currently no studies in the literature evaluating how much the coexistence of T2DM impacts neuromuscular fatigue and strength in patients with HF. Thus, the primary aim of this study will be to evaluate the differences in central and peripheral neuromuscular fatigue - determined by a submaximal exercise protocol with intermittent isometric contractions - in two groups of patients with heart failure with preserved ejection fraction with or without type 2 diabetes mellitus. Secondary outcomes will be related to the investigation of the differences in NO-mediated vascular function induced by a single passive movement of the leg, in the energy cost of walking, and in muscle oxygenation between the two groups.
详细描述
The progressive aging of the population of industrialized countries is accompanied by a dramatic increase in the prevalence of chronic diseases. Heart Failure (HF) is one of the major public health problems, with a high incidence of health care costs. In the general population, HF has a prevalence of approximately 1-2% of adults and rises to 10% in the population over 70 years of age.
Heart failure is defined as "the inability of the heart to supply blood adequately to meet the needs of the body, or the ability to do so only at the cost of increased ventricular pressures" Heart failure with preserved ejection fraction (HFpEF) is the most common condition in older adults and its prevalence is increasing as the population ages.
An important feature of patients with HFpEF is impaired exercise tolerance, resulting in worsening and reduced quality of life. Although the attention of the researchers has mostly focused on the definition of central pathophysiological and hemodynamic mechanisms, it has been seen how physical training can improve functional capacity through peripheral adaptive mechanisms that have not been yet clarified. Studies in the literature carried out on this type of patient suggest that the limited transport of oxygen to the muscles is one factor that can lead to the early development of fatigue during physical activity and reduced effort tolerance. A recent study also shows that patients with HFpEF have an increased susceptibility to both central and peripheral fatigue, suggesting that neuromuscular fatigue may be one of the main mechanisms limiting exercise in this population.
Type 2 diabetes mellitus (T2DM), which affects 90-95% of diabetic patients, is a co-condition of particular interest in heart failure, considering the large and ongoing increase in risk associated with heart failure among patients with T2DM. In T2DM, as in HF, it is observed an altered energy metabolism of the muscle and a shift in the type of muscle fibers. Furthermore, hyperglycemia influences neuromuscular function and appears to be one of the major causes of oxidative stress by affecting the intrinsic properties of the muscle (mitochondrial activity and function, myofilaments) related to the expression of force. The impact of diabetes on neuromuscular function is also linked to long-term complications such as diabetic peripheral neuropathy involving impairment of motor nerve conduction and vascular complications. This opens up a rather complex picture that suggests that T2DM in patients with HF could contribute to a further decline in muscle strength by further reducing the aerobic capacity of these patients.
Objective of the study
研究设计
- 研究类型
- Observational
- 观察模型
- Case Control
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 65 Years 至 80 Years（Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Have a diagnosis of heart failure with preserved ejection fraction (>50%, NYHA class II - III)
- •Have an age between 65 and 80 years
- •Have at least one hospitalization for heart failure during the previous 10 years
- •Have a diagnosis of diabetes for no more than 10 years at the time of cardiology examination
排除标准
- •Unstable diabetes documented by HbA1c ≥ 9%
- •Significant additional valvular heart diseases
- •Unstable heart failure
- •Presence of a pacemaker or implanted defibrillator (AICD)
- •Changes in drug therapy in the previous three months because of clinical instability
- •Body mass index (BMI) > 35 and < 20 kg/m2
- •Orthopedic limitations that prevent the exercise
- •Presence of diagnosis and signs and symptoms of diabetic neuropathy (intensified perception of pain, burning or cold sensation, tingling, pins, and needles, hypo-hypersensitivity to touch)
- •Severe deconditioning (patient is confined to home) or vigorous physical activity (sports or similar activity, estimated as more than two hours/day of vigorous exercise)
结局指标
主要结局
Change of the isometric force
时间窗: baseline and up to 1400 secs
The change in maximal isometric force is a measure to estimate the central and peripheral fatigue. Assessment maximal isometric contractions (MVC) pre, at midway through the fatigue protocol, 10' post fatigue protocol and 30' after the fatigue protocol. Maximum force reduction expressed in Newtons will be analyzed. Subjects will be seated upright with back support. The hip and knee will be flexed to 90° and the force will be measured by a force transducer. Change in MCV will be calculated as the difference in percentage between the post-pre fatigue task, as follows: (MVCpost - MVCpre) / MVCpre \*100, and expressed as percentage.
次要结局
- Nitric oxide-mediated vasodilation(Baseline)
- Change in muscle oxygenation(Up to 12 seconds)
- Evaluation of the energy cost of walking(Baseline)
- Evaluation of Angle of the pennation of Vastus Lateralis(Baseline)
- Evaluation of the Volume of Quadriceps(Baseline)
- Change of maximal Voluntary Activation (VA)(baseline and up to 1400 secs)
- Change of Rate of Perceived Exertion(baseline and up to 1400 secs)
- Time to Failure (t-lim)(Up to 1400 secs)
- Muscle electromyography(baseline and up to 1400 secs)