Assessment of cardiac autonomic neuropathy in long standing type 2 diabetic women

Association of arterial stiffness and neuropathy in diabetes: a systematic review and meta-analysis

Evidence is still emerging on the relationships of arterial stiffness with cardiac autonomic neuropathy (CAN) and peripheral neuropathy (PN). To our knowledge no systematic reviews or meta-analyses of these associations have been published. The purpose of our review was to assess the association of arterial stiffness with each type of neuropathy. Medline and Embase were systematically searched for observational studies of arterial stiffness and neuropathy.The systematic review of 60 studies (25 for CAN and 37 for PN), 59 including people with diabetes, showed arterial stiffness overall was higher in people with neuropathy than people without neuropathy. Forty-three studies were included in the meta-analysis. For CAN (19 studies), arterial stiffness was increased in people with neuropathy compared with without, as measured by pulse wave velocity (PWV) (mean difference: 1.32 m/s, 95% CI 0.82 to 1.81, p<0.00001), pulse pressure (PP) (mean difference: 6.25 mmHg, 95% CI 4.51 to 7.99, p<0.00001) or augmentation index (mean difference: 5.52%, 95% CI 3.46 to 7.58, p<0.0001). For PN (26 studies), arterial stiffness was increased in people with neuropathy compared with those without, as measured by PWV (mean difference: 1.22 m/s, 95% CI 0.87 to 1.58, p<0.00001) or PP (mean difference: 4.59 mmHg, 95% CI 2.96 to 6.22, p<0.00001). Only two cohort studies were located so the temporality of the association between arterial stiffness and neuropathy remains unclear. Increased arterial stiffness is associated with CAN and PN.PROSPERO registration number: CRD42019129563.

Leisure-Time Physical Activity and Glycemic Control Independently Predicts Cardiac Autonomic Neuropathy in Type 2 Diabetes Mellitus

BACKGROUND

Though cardiac autonomic neuropathy (CAN) is a common complication of type 2 diabetes mellitus (T2DM); still, there is lack of clarity on pathophysiological correlates for its onset and progression. Therefore, the purpose of this study was to investigate the predictive ability of lifestyle and cardiometabolic risk factors for CAN in T2DM patients.

METHODS

A total of 105 Indian T2DM patients were recruited in the present study. Cardiometabolic risk factors, such as glycemic control, lipids, resting heart rate, systolic and diastolic blood pressure, and lifestyle risk parameters, such as physical activity levels and sleep quality were assessed. Standard cardiovascular autonomic reflex tests were performed for diagnosing CAN by Ewing's criteria.

RESULTS

Leisure-time physical activity and glycosylated hemoglobin were significant independent predictors of CAN in T2DM. Leisure-time physical activity and glycosylated hemoglobin predicted the occurrence of CAN at cutoff values ≤4.68 metabolic equivalent-hours per week (P = .007) and >7.5% (P = .002), respectively.

CONCLUSIONS

The T2DM patients should be encouraged to engage in leisure-time physical activity of at least 4.68 metabolic equivalent-hours per week (equivalent to 1.2 h of walk or 0.6 h of jog per week) and therapeutic strategies for controlling hyperglycemia in T2DM should aim to reduce glycosylated hemoglobin below 7.5% to reduce CAN occurrence.

Carvedilol improves heart rate variability indices, biomarkers but not cardiac nerve density in streptozotocin-induced T2DM model of diabetic cardiac autonomic neuropathy

OBJECTIVES

There has been increasing recognition of the significant relationship between the autonomic nervous system and cardiovascular sequel in diabetes mellitus (DM) patients. Diabetic cardiac autonomic neuropathy (DCAN) still poses a treatment challenge in the clinical settings despite several research interventions. This study was designed to investigate the effect of carvedilol on experimentally induced DCAN in type 2 DM rat model.

METHODS

DCAN was induced in 42 Wistar rats using high fat diet (HFD) for eight weeks, thereafter streptozotocin (STZ) at 25 mg/kg daily for five days. DCAN features were then assessed using non-invasive time and frequency varying holter electrocardiogram (ECG), invasive biomarkers, cardiac histology and cardiac nerve density.

RESULTS

Carvedilol significantly ameliorated the effects of DCAN on noradrenaline (p=0.010) and advanced glycated end products (AGEs) (p<0.0001). Similarly, carvedilol reversed the reduction in levels of antioxidants, sorbitol dehydrogenase (SD) activity (p=0.009) nerve growth factors (p<0.0001) and choline acetyl-transferase (p=0.031) following DCAN induction. Furthermore, heart rate variability (HRV) indices which were also reduced with DCAN induction were also ameliorated by carvedilol. However, carvedilol had no significant effect on cardiac neuronal dystrophy and reduced cardiac nerve densities.

CONCLUSIONS

Carvedilol improves physiological HRV indices and biomarkers but not structural lesions. Early detection of DCAN and intervention with carvedilol may prevent progression of autonomic neurologic sequel.

Prevalence, risk factors, and prognosis of orthostatic hypotension in diabetic patients: A systematic review and meta-analysis

BACKGROUND

Orthostatic hypotension (OH) is a major clinical sign of cardiovascular autonomic dysfunction in diabetic patients. Our aim was to quantitatively evaluate the prevalence and risk factors of OH in patients with diabetes mellitus (DM) and assess its prognosis.

METHODS

A comprehensive search of the PubMed, Embase, China National Knowledge Infrastructure, VIP Chinese Journal, Wanfang, and SINOMED databases was conducted for related published work up to September 25, 2016, and manually searched eligible studies from the references in accordance with the inclusion criteria.

RESULTS

We included 21 studies in the analysis, with a total sample size of 13,772. The pooled prevalence of OH in DM was 24% (95% confidence interval [CI]: 19-28%). Potential risk factors, that is, glycosylated hemoglobin A (HbA1c) (odds ratio [OR], 1.13, 95% CI, 1.07-1.20), hypertension (OR, 1.02, 95% CI, 1.01-1.02), and diabetic nephropathy (OR, 2.37, 95% CI, 1.76-3.19), were significantly associated with OH in DM. In addition, the prognosis of OH in DM was associated with higher risk of total mortality and cardiovascular events.

CONCLUSION

The pooled prevalence of OH in DM appears high. HbA1c, hypertension, and diabetic nephropathy are risk factors for OH in DM. OH indicates poor prognosis in diabetic patients. Attention should be focused on diabetic patients with the stated risk factors to prevent OH.