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Journal of Family Medicine and Primary... Dec 2023Diabetic retinopathy, a form of microvasculopathy, is the leading cause of the visual abnormality. However, there is no conclusive evidence of the relationship of...
CONTEXT
Diabetic retinopathy, a form of microvasculopathy, is the leading cause of the visual abnormality. However, there is no conclusive evidence of the relationship of systemic vascular dysfunction with retinal microvasculopathy. In addition, diabetes-associated cardiac autonomic neuropathy may also compromise vascular function.
AIMS
The present study intends to correlate arterial stiffness, endothelial function, and heart rate variability (HRV) as a standardized measure of cardiac autonomic neuropathy with diabetic retinopathy.
SETTINGS AND DESIGN
The present cross-sectional, observational study was conducted in the Department of Physiology.
MATERIALS AND METHODS
Twenty subjects were recruited in group 1 (T2DM, type 2 diabetes mellitus patients, without retinopathy) and group 2 (T2DM with retinopathy). The vascular parameters such as heart rate, peripheral and central blood pressure, augmentation index [AIx (%)], brachial -ankle pulse wave velocity (baPWV), and reactive hyperaemia index (RHI) were recorded.
STATISTICAL ANALYSIS USED
Independent sample -test (for parametric data) and Mann-Whitney test (for non-parametric data) were employed to compare the variables of two groups. Spearman correlation was used to examine the relationship among the parameters. Linear regression analysis was performed to examine the important vascular predictor for diabetic retinopathy.
RESULTS
baPWV was significantly higher in group 2 than in group 1 and positively associated with group 2. RHI was significantly less in group 2 than group 1 and negatively associated with group 2. Among HRV metrics, standard deviation of successive differences (SDSD), root mean square of successive differences between normal heartbeats (RMSSD), and high frequency (HF) power were significantly decreased in group 2 than in group 1. SDSD, RMSSD, and HF were negatively associated with group 2. RHI emerged as a significant predictor of diabetic retinopathy following linear regression.
CONCLUSIONS
Overall, the result of the present study indicates that metabolic dysregulation of glucose may affect the normal functioning of the autonomic nervous system and vascular function. Therefore, screening of vascular function and cardiac autonomic tone may be advocated in diabetic patients in routine clinics to examine the existence of any comorbid condition, such as diabetic retinopathy, as systemic vascular changes may also affect ophthalmic vasculature.
PubMed: 38361899
DOI: 10.4103/jfmpc.jfmpc_909_23 -
Annals of African Medicine 2024Time in range (TIR), a metric of continuous glucose monitoring (CGM) provides better information regarding the individual's glycemic variability than a static measure...
INTRODUCTION
Time in range (TIR), a metric of continuous glucose monitoring (CGM) provides better information regarding the individual's glycemic variability than a static measure like glycated hemoglobin (HbA1c). TIR is emerging as an independent risk factor for diabetic complications, both microvascular and macrovascular complications independent of HbA1c. Hence, this study evaluates the association between TIR and cardiac autonomic neuropathy (CAN) in type 2 diabetic patients.
MATERIALS AND METHODS
A total of 42 patients with type 2 diabetes mellitus were enrolled in this study and underwent a 3-day CGM using the "FreeStyle Libre Pro Flash Glucose Monitoring System Sensor" along with tests for CAN within the 3 days of attaching the CGM.
RESULTS
Out of 42 patients, 36 patients (85.7%) were diagnosed with CAN (early CAN 57.1% and definite CAN 28.6%) and the mean TIR was 64.4% ±23.5%. Out of those with TIR <70%, 42.9% were affected with definite CAN compared to only 14.3% among those with TIR >70%. Patients with more severe CAN were found to have a lower TIR (P = 0.115).
CONCLUSION
The study found a high prevalence of cardiac autonomic neuropathy (CAN) of around 85.7% in type 2 diabetes patients. Lower TIR values were associated with a higher incidence of definite CAN (42.9% vs. 14.3% in TIR <70% vs. >70% groups). The findings suggest TIR is inversely associated with the presence and severity of cardiac autonomic neuropathy in type 2 diabetic patients and also a potential link between TIR and CAN severity.
Topics: Humans; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Blood Glucose; Blood Glucose Self-Monitoring; Continuous Glucose Monitoring; Nervous System Diseases
PubMed: 38358166
DOI: 10.4103/aam.aam_117_23 -
Frontiers in Endocrinology 2024Autonomic and sensory neuropathy have been observed in both prediabetes and manifest diabetes mellitus. However, there is a lack of available data regarding whether...
INTRODUCTION
Autonomic and sensory neuropathy have been observed in both prediabetes and manifest diabetes mellitus. However, there is a lack of available data regarding whether patients at a moderate or high risk of developing diabetes, yet without a current diagnosis of prediabetes or diabetes, exhibit an increased prevalence of neuropathy.
METHODS
FINDRISC (Finnish Diabetes Risk Score) was used to classify individuals at risk (≥12 points, = 44; control <12 points, = 28). HbA1c levels >5.6% served as exclusion criteria, and patients with known medical conditions predisposing to neuropathy were also excluded. Cardiac autonomic function (Ewing tests) and peripheral sensory neuropathy (Neurometer and Q-sense) were assessed by standardized protocols, and their potential association with increased FINDRISC points was analyzed using a regression model.
RESULTS
Mean age was 46.7 ± 14.3 years in the control and 55.7 ± 14.1 years in the increased risk group. Male/female ratio did not differ. Individuals with increased risk of diabetes were more obese (BMI: 29.9 ± 12.5 kg/m vs. 25.9 ± 8.9 kg/m). Additionally, hypertension was more frequent among them (68.2% vs. 17.9%), and their lipid parameters were also less favorable. Parasympathetic neuropathy was present in both groups (56.8% vs. 32.1%, respectively). Sympathetic neuropathy was not found. Sensory nerve dysfunction was of low prevalence in the high-risk group and did not occur in healthy controls. In multiple logistic regression analysis, HbA1c exhibited an independent association with parasympathetic neuropathy (OR: 5.9; 95% CI: 1.08-32.68; < 0.041).
DISCUSSION
An increased risk of developing prediabetes/diabetes does not appear to have a strong correlation with an increased likelihood of developing autonomic or sensory neuropathy. However, the etiology behind the occurrence of parasympathetic autonomic neuropathy in healthy individuals remains unknown.
Topics: Humans; Female; Male; Adult; Middle Aged; Prediabetic State; Pilot Projects; Diabetes Mellitus, Type 2; Glycated Hemoglobin; Diabetic Neuropathies
PubMed: 38352713
DOI: 10.3389/fendo.2024.1302013 -
Frontiers in Neurology 2024Guillain-Barré syndrome (GBS) is a rare disease that affects almost 0.8-1.9 cases per 100,000 people worldwide every year. This is the most prevalent cause of subacute... (Review)
Review
INTRODUCTION
Guillain-Barré syndrome (GBS) is a rare disease that affects almost 0.8-1.9 cases per 100,000 people worldwide every year. This is the most prevalent cause of subacute flaccid paralyzing illness today. It is a subacute inflammatory demyelinating polyradiculoneuropathy; the typical scenario involves ascending symmetrical flaccid paralysis, but in some circumstances, sensory, autonomic, and cranial neuropathy may also be involved. Several vaccines have been found to have complications since the previous century. Numerous case reports of GBS in the literature have been reported following COVID-19 vaccines in recent times.
OBJECTIVE
This study aimed to conduct a comprehensive examination of GBS cases that have been reported after COVID-19 vaccines; to analyze the descriptive statistical analysis of data gathered regarding clinical, laboratory, electrophysiological, and radiological characteristics; to discuss, based on the available evidence, whether the disease has a preference for a particular vaccine type; and to speculate on the potential pathogenesis.
METHODOLOGY
This review has been carried out by recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
RESULT
Reviewing 60 case reports illustrated that most of them are from the USA (18.1%) and the majority of affected individuals were males (60%). The results favored the association between vector-based SARS-CoV-2 vaccine, particularly AstraZeneca vaccine, and the GBS. The mean of symptoms onset is 11.4 days. The results of diagnostic tests such as LP are consistent mostly with albumin-cytological dissociation (81.81%), where brain and spine MRI was unremarkable in 59.52%. Regarding electrodiagnostic tests, AIDP is the most common variant (61.81%). The management was not consistent among the case reports. However, IVIG is the most frequent way of treating these patients (68.33%). The functional outcome was documented in 47 patients; 65% improved with medical management.
CONCLUSION
This study aimed to conduct a systematic review of reported cases of GBS following COVID-19 vaccines and descriptive statistical analysis of collected data on clinical, laboratory, electrophysiological, and radiological features, to discuss, based on available results, whether the disease has a predilection to a specific vaccine type and to speculate the potential pathogenesis.
PubMed: 38352138
DOI: 10.3389/fneur.2024.1332364 -
Diabetology & Metabolic Syndrome Feb 2024Patients with diabetes demonstrate early left ventricular systolic dysfunction. Notably reduced global longitudinal strain (GLS) is related to poor outcomes, the...
Early signs of myocardial systolic dysfunction in patients with type 2 diabetes are strongly associated with myocardial microvascular dysfunction independent of myocardial fibrosis: a prospective cohort study.
BACKGROUND
Patients with diabetes demonstrate early left ventricular systolic dysfunction. Notably reduced global longitudinal strain (GLS) is related to poor outcomes, the underlying pathophysiology is however still not clearly understood. We hypothesized that pathophysiologic changes with microvascular dysfunction and interstitial fibrosis contribute to reduced strain.
METHODS
211 patients with type 2 diabetes and 25 control subjects underwent comprehensive cardiovascular phenotyping by magnetic resonance imaging. Myocardial blood flow (MBF), perfusion reserve (MPR), extracellular volume (ECV), and 3D feature tracking GLS and global circumferential (GCS) and radial strain (GRS) were quantified.
RESULTS
Patients (median age 57 [IQR 50, 67] years, 70% males) had a median diabetes duration of 12 [IQR 6, 18] years. Compared to control subjects GLS, GCS, and GRS were reduced in the total diabetes cohort, and GLS was also reduced in the sub-group of patients without diabetic complications compared to control subjects (controls - 13.9 ± 2.0%, total cohort - 11.6 ± 3.0%; subgroup - 12.3 ± 2.6%, all p < 0.05). Reduced GLS, but not GCS or GRS, was associated with classic diabetes complications of albuminuria (UACR ≥ 30 mg/g) [β (95% CI) 1.09 (0.22-1.96)] and autonomic neuropathy [β (95% CI) 1.43 (0.54-2.31)] but GLS was not associated with retinopathy or peripheral neuropathy. Independently of ECV, a 10% increase in MBF at stress and MPR was associated with higher GLS [multivariable regression adjusted for age, sex, hypertension, smoking, and ECV: MBF stress (β (95% CI) - 0.2 (- 0.3 to - 0.08), MPR (β (95% CI) - 0.5 (- 0.8 to - 0.3), p < 0.001 for both]. A 10% increase in ECV was associated with a decrease in GLS in univariable [β (95% CI) 0.6 (0.2 to 1.1)] and multivariable regression, but this was abolished when adjusted for MPR [multivariable regression adjusted for age, sex, hypertension, smoking, and MPR (β (95% CI) 0.1 (- 0.3 to 0.6)]. On the receiver operating characteristics curve, GLS showed a moderate ability to discriminate a significantly lowered stress MBF (AUC 0.72) and MPR (AUC 0.73).
CONCLUSIONS
Myocardial microvascular dysfunction was independent of ECV, a biomarker of myocardial fibrosis, associated with GLS. Further, 3D GLS could be a potential screening tool for myocardial microvascular dysfunction. Future directions should focus on confirming these results in longitudinal and/or interventional studies.
PubMed: 38350975
DOI: 10.1186/s13098-024-01285-0 -
Endocrine Journal Apr 2024A 67-year-old man with type 1 diabetes, Cronkhite-Canada syndrome, and membranous nephropathy who received insulin therapy was admitted to our hospital with right... (Review)
Review
A 67-year-old man with type 1 diabetes, Cronkhite-Canada syndrome, and membranous nephropathy who received insulin therapy was admitted to our hospital with right hemiplegia and dysarthria. Brain magnetic resonance imaging revealed a lesion with a high diffusion-weighted imaging signal and low apparent diffusion coefficient signal in the posterior limb of the left internal capsule. He was hypoglycemic with a blood glucose level of 56 mg/dL (3.1 mmol/L). Following glucose administration, the patient's symptoms resolved within several hours. The patient experienced similar transient hypoglycemic hemiplegia at midnight, three times within 10 days. In a literature review of 170 cases of hypoglycemic hemiplegia, 26 cases of recurrent hemiplegia were investigated. Recurrent hypoglycemic hemiplegia occurs more frequently on the right side than on the left side, and most recurrences occur within approximately a week, almost exclusively at midnight and in the early morning. We speculate that hypoglycemia-associated autonomic failure may be involved in the nocturnal recurrence of episodes. In our patient, depleted endogenous insulin secretion and lipodystrophy at the injection site, may have acted as additional factors, leading to severe hypoglycemia despite the absence of apparent autonomic neuropathy. Clinically, it is important to recognize hypoglycemia as a cause of hemiplegia to avoid unnecessary intervention and to maintain an appropriate blood glucose level at midnight and early in the morning to prevent recurrent hypoglycemic hemiplegia.
Topics: Humans; Male; Hemiplegia; Aged; Hypoglycemia; Recurrence; Diabetes Mellitus, Type 1; Blood Glucose; Insulin
PubMed: 38346770
DOI: 10.1507/endocrj.EJ23-0324 -
International Journal of Molecular... Feb 2024Neuropathy is a serious and frequent complication of type 2 diabetes (T2DM). This study was carried out to search for genetic factors associated with the development of...
Neuropathy is a serious and frequent complication of type 2 diabetes (T2DM). This study was carried out to search for genetic factors associated with the development of diabetic neuropathy by whole exome sequencing. For this study, 24 patients with long-term type 2 diabetes with neuropathy and 24 without underwent detailed neurological assessment and whole exome sequencing. Cardiovascular autonomic function was evaluated by cardiovascular reflex tests. Heart rate variability was measured by the triangle index. Sensory nerve function was estimated by Neurometer and Medoc devices. Neuropathic symptoms were characterized by the neuropathy total symptom score (NTSS). Whole exome sequencing (WES) was performed on a Thermo Ion GeneStudio S5 system determining the coding sequences of approximately 32,000 genes comprising 50 million base pairs. Variants were detected by Ion Reporter software and annotated using ANNOVAR, integrating database information from dbSNP, ClinVar, gnomAD, and OMIM. Integrative genomics viewer (IGV) was used for visualization of the mapped reads. We have identified genetic variants that were significantly associated with increased (22-49-fold) risk of neuropathy (rs2032930 and rs2032931 of (, rs604349 of ( and with reduced (0.07-0.08-fold) risk (rs917778 of and rs2234753 of (RXRA) genes). The rs2032930 showed a significant correlation with current perception thresholds measured at 5 Hz and 250 Hz for n. medianus ( = 0.042 and = 0.003, respectively) and at 5 Hz for n. peroneus ( = 0.037), as well as the deep breath test ( = 0.022) and the NTSS ( = 0.023). The rs2032931 was associated with current perception thresholds ( = 0.003 and = 0.037, respectively), deep breath test ( = 0.022), and NTSS ( = 0.023). The rs604349 correlated with values measured at 2000 ( = 0.049), 250 ( = 0.018), and 5 Hz ( = 0.005) for n. medianus, as well as warm perception threshold measured by Medoc device ( = 0.042). The rs2234753 showed correlations with a current perception threshold measured at 2000 Hz for n. medianus ( = 0.020), deep breath test ( = 0.040), and NTSS ( = 0.003). There was a significant relationship between rs91778 and cold perception threshold ( = 0.013). In our study, genetic variants have been identified that may have an impact on the risk of neuropathy developing in type 2 diabetic patients. These results could open up new opportunities for early preventive measures and might provide targets for new drug developments in the future.
Topics: Humans; Diabetes Mellitus, Type 2; Sensory Thresholds; Diabetic Neuropathies; Autonomic Nervous System; Sensation
PubMed: 38339094
DOI: 10.3390/ijms25031815 -
Scientific Reports Jan 2024Autonomic symptom questionnaires are frequently used to assess dysautonomia. It is unknown whether subjective dysautonomia obtained from autonomic questionnaires...
Autonomic symptom questionnaires are frequently used to assess dysautonomia. It is unknown whether subjective dysautonomia obtained from autonomic questionnaires correlates with objective dysautonomia measured by quantitative autonomic testing. The objective of our study was to determine correlations between subjective and objective measures of dysautonomia. This was a retrospective cross-sectional study conducted at Brigham and Women's Faulkner Hospital Autonomic Laboratory between 2017 and 2023 evaluating the patients who completed autonomic testing. Analyses included validated autonomic questionnaires [Survey of Autonomic Symptoms (SAS), Composite Autonomic Symptom Score 31 (Compass-31)] and standardized autonomic tests (Valsalva maneuver, deep breathing, sudomotor, and tilt test). The autonomic testing results were graded by a Quantitative scale for grading of cardiovascular reflexes, sudomotor tests and skin biopsies (QASAT), and Composite Autonomic Severity Score (CASS). Autonomic testing, QASAT, CASS, and SAS were obtained in 2627 patients, and Compass-31 in 564 patients. The correlation was strong between subjective instruments (SAS vs. Compass-31, r = 0.74, p < 0.001) and between objective instruments (QASAT vs. CASS, r = 0.81, p < 0.001). There were no correlations between SAS and QASAT nor between Compass-31 and CASS. There continued to be no correlations between subjective and objective instruments for selected diagnoses (post-acute sequelae of COVID-19, n = 61; postural tachycardia syndrome, 211; peripheral autonomic neuropathy, 463; myalgic encephalomyelitis/chronic fatigue syndrome, 95; preload failure, 120; post-treatment Lyme disease syndrome, 163; hypermobile Ehlers-Danlos syndrome, 213; neurogenic orthostatic hypotension, 86; diabetes type II, 71, mast cell activation syndrome, 172; hereditary alpha tryptasemia, 45). The lack of correlation between subjective and objective instruments highlights the limitations of the commonly used questionnaires with some patients overestimating and some underestimating true autonomic deficit. The diagnosis-independent subjective-objective mismatch further signifies the unmet need for reliable screening surveys. Patients who overestimate the symptom burden may represent a population with idiosyncratic autonomic-like symptomatology, which needs further study. At this time, the use of autonomic questionnaires as a replacement of autonomic testing cannot be recommended.
Topics: Humans; Female; Retrospective Studies; Cross-Sectional Studies; Surveys and Questionnaires; Postural Orthostatic Tachycardia Syndrome; Penicillanic Acid
PubMed: 38291116
DOI: 10.1038/s41598-024-52368-x -
Annual Review of Medicine Jan 2024Diabetic neuropathy is a highly prevalent complication of diabetes. It consists of a broad range of neuropathic conditions, such as distal symmetric polyneuropathy and... (Review)
Review
Diabetic neuropathy is a highly prevalent complication of diabetes. It consists of a broad range of neuropathic conditions, such as distal symmetric polyneuropathy and various forms of autonomic neuropathies involving the cardiovascular, gastrointestinal, and urogenital systems. Prevention or diagnosis in early stages of disease is crucial to prevent symptomatic onset and progression, particularly in the absence of current disease-modifying therapies. In this review, we describe the four main types of diabetic neuropathy. We review current understanding with respect to diagnosis and treatment while highlighting knowledge gaps and future directions.
Topics: Humans; Diabetic Neuropathies; Diabetes Mellitus
PubMed: 38285516
DOI: 10.1146/annurev-med-043021-033114