Cardiovascular autonomic neuropathy and bone metabolism in Type 1 diabetes

Significance of non-motor symptoms and development of a screening tool for osteoporosis in Parkinson's disease

BACKGROUND AND PURPOSE

Parkinson's disease (PD) patients have a higher likelihood of having osteoporosis compared to controls, therefore deserving special attention. This study was to 1) investigate the association of non-motor symptoms with osteoporosis amongst PD patients, and 2) develop screening tools for osteoporosis.

MATERIALS AND METHODS

PD Patients were included (n = 109). The factors/variables were obtained from clinical records due to the retrospective nature of this study. The bone mineral density (BMD) of the lumbar spine and femoral neck was examined using a dual-energy X-ray absorptiometry machine, according to which they were categorized as either having (T-score ≤ -2.5) or not having osteoporosis (T-score>-2.5) at the two sites. The non-motor symptoms were assessed using clinical scales, including non-motor experiences of daily living, depression, anxiety, cognitive function, and autonomic function. The potential covariates included demographic and clinical factors/variables, such as age and sex. Logistic regression was used to investigate the associations and establish the screening tools.

RESULTS

Patients with autonomic dysfunction had significantly (p = 0.011) higher odds of having femoral neck osteoporosis compared to those with no/minimal dysfunction after adjusting for sex, disease duration, and body mass index, demonstrating a strong association (odds ratio=12.81). Based on the four factors/variables, a screening tool with a good accuracy was established (C-statistic = 0.85).

CONCLUSION

PD patients with autonomic dysfunction had greater odds of having femoral neck osteoporosis compared to those with no/minimal dysfunction. The screening tool may lay a foundation for developing screening models with higher accuracy to identify which PD patients may require a BMD test.

Protocol for the combined cardiometabolic deep phenotyping and registry-based 20-year follow-up study of the Inter99 cohort

INTRODUCTION

The population-based Inter99 cohort has contributed extensively to our understanding of effects of a systematic screening and lifestyle intervention, as well as the multifactorial aetiology of type 2 diabetes (T2D) and cardiovascular disease. To understand causes, trajectories and patterns of early and overt cardiometabolic disease manifestations, we will perform a combined clinical deep phenotyping and registry follow-up study of the now 50-80 years old Inter99 participants.

METHODS AND ANALYSIS

The Inter99 cohort comprises individuals aged 30-60 years, who lived in a representative geographical area of greater Copenhagen, Denmark, in 1999. Age-stratified and sex-stratified random subgroups were invited to participate in either a lifestyle intervention (N=13 016) or questionnaires (N=5264), while the rest served as a reference population (N=43 021). Of the 13 016 individuals assigned to the lifestyle intervention group, 6784 (52%) accepted participation in a baseline health examination in 1999, including screening for cardiovascular risk factors and prediabetic conditions. In total, 6004 eligible participants, who participated in the baseline examination, will be invited to participate in the deep phenotyping 20-year follow-up clinical examination including measurements of anthropometry, blood pressure, arterial stiffness, cardiometabolic biomarkers, coronary artery calcification, heart rate variability, heart rhythm, liver stiffness, fundus characteristics, muscle strength and mass, as well as health and lifestyle questionnaires. In a subsample, 10-day monitoring of diet, physical activity and continuous glucose measurements will be performed. Fasting blood, urine and faecal samples to be stored in a biobank. The established database will form the basis of multiple analyses. A main purpose is to investigate whether low birth weight independent of genetics, lifestyle and glucose tolerance predicts later common T2D cardiometabolic comorbidities.

ETHICS AND DISSEMINATION

The study was approved by the Medical Ethics Committee, Capital Region, Denmark (H-20076231) and by the Danish Data Protection Agency through the Capital Region of Denmark's registration system (P-2020-1074). Informed consent will be obtained before examinations. Findings will be disseminated in peer-reviewed journals, at conferences and via presentations to stakeholders, including patients and public health policymakers.

TRIAL REGISTRATION NUMBER

NCT05166447.

Collagen turnover is associated with cardiovascular autonomic and peripheral neuropathy in type 1 diabetes: novel pathophysiological mechanism?

BACKGROUND

Diabetic cardiovascular autonomic neuropathy (CAN) and distal symmetrical polyneuropathy (DSPN) are severe diabetic complications. Collagen type VI (COL6) and III (COL3) have been associated with nerve function. We investigated if markers of COL6 formation (PRO-C6) and COL3 degradation (C3M) were associated with neuropathy in people with type 1 diabetes (T1D).

METHODS

In a cross-sectional study including 300 people with T1D, serum and urine PRO-C6 and C3M were obtained. CAN was assessed by cardiovascular reflex tests: heart rate response to deep breathing (E/I ratio), to standing (30/15 ratio) and to the Valsalva maneuver (VM). Two or three pathological CARTs constituted CAN. DSPN was assessed by biothesiometry. Symmetrical vibration sensation threshold above 25 V constituted DSPN.

RESULTS

Participants were (mean (SD)) 55.7 (9.3) years, 51% were males, diabetes duration was 40.0 (8.9) years, HbA1c was 63 (11 mmol/mol, (median (IQR)) serum PRO-C6 was 7.8 (6.2;11.0) ng/ml and C3M 8.3 (7.1;10.0) ng/ml. CAN and DSPN were diagnosed in 34% and 43% of participants, respectively. In models adjusted for relevant confounders a doubling of serum PRO-C6, was significantly associated with odds ratio > 2 for CAN and > 1 for DSPN, respectively. Significance was retained after additional adjustments for eGFR only for CAN. Higher serum C3M was associated with presence of CAN, but not after adjustment for eGFR. C3M was not associated with DSPN. Urine PRO-C6 analyses indicated similar associations.

CONCLUSIONS

Results show previously undescribed associations between markers of collagen turnover and risk of CAN and to a lesser degree DSPN in T1D.

Research for correlation between heart rate variability parameters and bone mineral density in patients of type 2 diabetes mellitus

PURPOSE

The relationship of CAN and BMD, fracture risk is still unclear in T2DM. The aim of the present study is to investigate the correlation between heart rate variability (HRV) and BMD in T2DM.

METHODS

The study included 276 patients with T2DM aged ≥ 50 years, and Cardiovascular Autonomic Reflex Tests (CARTs) were applied to divide patients into two groups: CAN ( ±). 24 h Ambulatory ECG was assessed for HRV, BMD was measured by dual-energy X-ray bone densitometry, and FRAX scores were calculated for 10-year hip fracture risk (HF¹) and major osteoporotic fracture risk (MOF). Adjusted regression analysis was performed to investigate influence factors for BMD and fracture risk. ROC curve was used to analyze the optimal cut-off point of LF/HF for screening osteoporosis.

RESULTS

Baseline data showed significant differences in the duration of T2DM, insulin resistance index (HOMA-IR), 25-hydroxyvitamin D[25(OH)D], femoral neck BMD, hip BMD, lumbar BMD, HF¹, and MOF between the CAN ( +) and CAN (-) groups. The proportion of patients with osteoporosis increased as the degree of CAN lesion increased. Correlation analysis showed that LF/HF was significantly correlated with BMD, especially with hip (r = - 0.534, p < 0.001). Regression analysis showed that LF/HF was a risk factor for reduced BMD and increased fracture risk. The optimal cut-point value for LF/HF to predict osteoporosis by ROC curve analysis was 3.17.

CONCLUSIONS

CAN is associated with reduced BMD and increased fracture risk in patients with T2DM, and LF/HF may have the potential to be a predictor of diabetic osteoporosis and have some clinical value in early diagnosis of diabetic osteoporosis and non-traumatic fractures in T2DM.

Distal symmetrical polyneuropathy is present in all individuals with diabetes and foot ulcers - and does not associate with healing time

We estimated the occurrence of diabetic neuropathy using six different diagnostic modalities in individuals with newly diagnosed diabetic foot ulcers (DFUs) and assessed the association with DFU healing time. All individuals with DFU had distal symmetrical polyneuropathy. Presence of neuropathy did not associate with ulcer healing time (p ≥ 0.12).

Cardiovascular Autonomic Neuropathy Is Associated With Increased Glucose Variability in People With Type 1 Diabetes

OBJECTIVE

We investigated the association between the cardiovascular autonomic neuropathy (CAN) diagnosis and glucose variability (GV) in type 1 diabetes (T1D), as autonomic dysfunction previously has been associated with increased GV.

RESEARCH DESIGN AND METHODS

CAN was assessed by three recommended cardiovascular reflex tests (CARTs). Glucose metrics were obtained from 10-day blinded continuous glucose monitoring (CGM). Between-group differences in GV indices were assessed by regression analyses in 24 participants with T1D with CAN and 24 matched control subjects without CAN.

RESULTS

The CAN diagnosis was associated with 4.9% (95% CI 1.0, 8.7) higher coefficient of variation (CV) (P = 0.014), 0.7 mmol/L (0.3, 1.1) higher SD (P = 0.002) of glucose, and 1.4 mmol/mol (0.0, 2.7) higher mean amplitude of glycemic excursions (P = 0.047). Lower measures of CARTs were associated with higher CV, SD, and time above range values.

CONCLUSIONS

The CAN diagnosis associates with a significantly higher GV in T1D, despite a high prevalence of routine CGM use.

Association between plasma apolipoprotein M and cardiac autonomic neuropathy in type 1 diabetes

AIM

Diabetes may lead to severe complications e.g. cardiac autonomic neuropathy (CAN) characterized by an increased risk of cardiovascular mortality. CAN is diagnosed by a decreased heart rate viability (HRV). Sphingosine-1-Phosphate (S1P) carried by the HDL-associated apolipoprotein M (apoM) is linked to a reduction in the heart rate, and treatment with an S1P-agonist increases HRV. The present study aimed to investigate if plasma apoM was associated with an increased risk of CAN.

METHODS

The study includes 278 individuals with Type 1 Diabetes recruited from Steno Diabetes Center in Copenhagen from 2010 to 2012.

RESULTS

A change of 0.1 µM plasma apoM was associated with the diagnosis of CAN (Odds ratio: 1.11 (1.02; 1.21), p = 0.013). ApoM plasma levels were also positively associated with CAN when adjusted for age and gender (Odds ratio: 1.11 (1.02; 1.21), p = 0.013) as well as lipids, beta-blockers, blood pressure, and alcohol (Odds ratio: 1.14 (1.04; 1.26), p = 0.005) and Hbga1c and time with diabetes (Odds ratio: 1.13 (1.02; 1.25), p = 0.01). Plasma apoM was also associated with a significantly lower SDNN as well as high frequency power in all adjusted models.

CONCLUSION

Increased plasma apoM was associated with an increased risk of CAN as well as a significant reduction in HRV indices. This could represent changes in parasympathetic activity, but, further studies are needed to also explore additional molecular alterations behind such observations.

Symptomatic diabetic autonomic neuropathy in type 1 diabetes (T1D): Findings from the T1D exchange

AIMS

We aimed to evaluate the contemporary prevalence of and risk factors for symptomatic diabetic autonomic neuropathy (DAN) in participants with type 1 diabetes (T1D) enrolled in the T1D Exchange Clinic Registry.

METHODS

DAN symptoms and severity were assessed with the Survey of Autonomic Symptoms (SAS) in adults with ≥5 years of T1D participating in the T1D Exchange from years 2010-2017. Associations of demographic, clinical, and laboratory factors with symptomatic DAN were assessed.

RESULTS

Of the 4919 eligible T1D participants, 965 (20%) individuals completed the SAS questionnaire [mean age 40 ± 17 years, median diabetes duration 20 years (IQR: 13,34), 64% female, 90% non-Hispanic White, and 82% with private insurance]. DAN symptoms were present in 166 (17%) of responders with 72% experiencing moderate severity symptoms or worse. Symptomatic DAN participants had higher hemoglobin A1c (p = 0.03), longer duration (p = 0.004), were more likely to be female (p = 0.03), and more likely to have lower income (p = 0.03) versus no DAN symptoms. Symptomatic DAN was associated with diabetic peripheral neuropathy (p < 0.0001), smoking (p = 0.002), cardiovascular disease (p = 0.02), depression (p < 0.001), and opioid use (p = 0.004).

CONCLUSIONS

DAN symptoms are common in T1D. Socioeconomic factors and psychological comorbidities may contribute to DAN symptoms and should be explored further.

The Potential of Current Noninvasive Wearable Technology for the Monitoring of Physiological Signals in the Management of Type 1 Diabetes: Literature Survey

Background

Monitoring glucose and other parameters in persons with type 1 diabetes (T1D) can enhance acute glycemic management and the diagnosis of long-term complications of the disease. For most persons living with T1D, the determination of insulin delivery is based on a single measured parameter—glucose. To date, wearable sensors exist that enable the seamless, noninvasive, and low-cost monitoring of multiple physiological parameters.

Objective

The objective of this literature survey is to explore whether some of the physiological parameters that can be monitored with noninvasive, wearable sensors may be used to enhance T1D management.

Methods

A list of physiological parameters, which can be monitored by using wearable sensors available in 2020, was compiled by a thorough review of the devices available in the market. A literature survey was performed using search terms related to T1D combined with the identified physiological parameters. The selected publications were restricted to human studies, which had at least their abstracts available. The PubMed and Scopus databases were interrogated. In total, 77 articles were retained and analyzed based on the following two axes: the reported relations between these parameters and T1D, which were found by comparing persons with T1D and healthy control participants, and the potential areas for T1D enhancement via the further analysis of the found relationships in studies working within T1D cohorts.

Results

On the basis of our search methodology, 626 articles were returned, and after applying our exclusion criteria, 77 (12.3%) articles were retained. Physiological parameters with potential for monitoring by using noninvasive wearable devices in persons with T1D included those related to cardiac autonomic function, cardiorespiratory control balance and fitness, sudomotor function, and skin temperature. Cardiac autonomic function measures, particularly the indices of heart rate and heart rate variability, have been shown to be valuable in diagnosing and monitoring cardiac autonomic neuropathy and, potentially, predicting and detecting hypoglycemia. All identified physiological parameters were shown to be associated with some aspects of diabetes complications, such as retinopathy, neuropathy, and nephropathy, as well as macrovascular disease, with capacity for early risk prediction. However, although they can be monitored by available wearable sensors, most studies have yet to adopt them, as opposed to using more conventional devices.

Conclusions

Wearable sensors have the potential to augment T1D sensing with additional, informative biomarkers, which can be monitored noninvasively, seamlessly, and continuously. However, significant challenges associated with measurement accuracy, removal of noise and motion artifacts, and smart decision-making exist. Consequently, research should focus on harvesting the information hidden in the complex data generated by wearable sensors and on developing models and smart decision strategies to optimize the incorporation of these novel inputs into T1D interventions.

Cardiovascular Autonomic Neuropathy in Type 1 Diabetes Is Associated With Disturbances in TCA, Lipid, and Glucose Metabolism

INTRODUCTION

Diabetic cardiovascular autonomic neuropathy (CAN) is associated with increased mortality and morbidity. To explore metabolic mechanisms associated with CAN we investigated associations between serum metabolites and CAN in persons with type 1 diabetes (T1D).

MATERIALS AND METHODS

Cardiovascular reflex tests (CARTs) (heart rate response to: deep breathing; lying-to-standing test; and the Valsalva maneuver) were used to diagnose CAN in 302 persons with T1D. More than one pathological CARTs defined the CAN diagnosis. Serum metabolomics and lipidomic profiles were analyzed with two complementary non-targeted mass-spectrometry methods. Cross-sectional associations between metabolites and CAN were assessed by linear regression models adjusted for relevant confounders.

RESULTS

Participants were median (IQR) aged 55(49, 63) years, 48% males with diabetes duration 39(32, 47) years, HbA_1c 63(55,69) mmol/mol and 34% had CAN. A total of 75 metabolites and 106 lipids were analyzed. In crude models, the CAN diagnosis was associated with higher levels of hydroxy fatty acids (2,4- and 3,4-dihydroxybutanoic acids, 4-deoxytetronic acid), creatinine, sugar derivates (ribitol, ribonic acid, myo-inositol), citric acid, glycerol, phenols, phosphatidylcholines and lower levels of free fatty acids and the amino acid methionine (p<0.05). Upon adjustment, positive associations with the CAN diagnoses were retained for hydroxy fatty acids, tricarboxylic acid (TCA) cycle-based sugar derivates, citric acid, and phenols (P<0.05).

CONCLUSION

Metabolic pathways, including the TCA cycle, hydroxy fatty acids, phosphatidylcholines and sugar derivatives are associated with the CAN diagnosis in T1D. These pathway may be part of the pathogeneses leading to CAN and may be modifiable risk factors for the complication.

Cardiovascular autonomic neuropathy and the impact on progression of diabetic kidney disease in type 1 diabetes

INTRODUCTION

We investigated the association between cardiovascular autonomic neuropathy (CAN) and decline in kidney function in type 1 diabetes.

RESEARCH DESIGN AND METHODS

We included 329 persons with type 1 diabetes. CAN was assessed by cardiovascular reflex tests (CARTs): heart rate response to deep breathing (E/I ratio), to standing (30/15 ratio) and to the Valsalva maneuvre. Two or more pathological CARTs defined CAN diagnosis. Outcomes were yearly change in albuminuria or yearly change in estimated glomerular filtration rate (eGFR). An endpoint of eGFR decline >30%, development of end-stage kidney disease (ESKD) or death was examined.Associations were assessed by linear and Cox regression.

RESULTS

Participants were aged 55.2 (9.4) years, 52% were male, with a diabetes duration of 40.1 (8.9) years, HbA_1c of 7.9% (62.5 mmol/mol), eGFR 77.9 (27.7) mL/min/1.73 m², urinary albumin excretion rate of 14.5 (7-58) mg/24 hours, and 31% were diagnosed with CAN.CAN was associated with a 7.8% higher albuminuria increase per year (95% CI: 0.50% to 15.63%, p=0.036) versus no CAN. The endpoint of ESKD, all-cause mortality and ≥30% decline in eGFR was associated with CAN (HR=2.497, p=0.0254).

CONCLUSION

CAN and sympathetic dysfunction were associated with increase in albuminuria in individuals with type 1 diabetes suggesting its role as a potential marker of diabetic kidney disease progression.

Association between diabetic neuropathy and osteoporosis in patients: a systematic review and meta-analysis

OBJECTIVES

Many studies have explored the association between neuropathy and osteoporosis in patients with diabetes mellitus. However, the results still remain inconsistent and controversial. We aimed to estimate the association between diabetic neuropathy and osteoporosis.

METHODS

Databases, including PubMed, Embase, Web of Science, the Cochrane library, Chinese Biomedical Literature Database (CBM), and Wanfang, were screened from inception to 30 March 2020. Studies were selected and data were extracted by two independent reviewers. Study characteristics and quality sections were reviewed independently. Pooled ORs and 95% CIs were calculated using random effects model when evidence of heterogeneity was present; otherwise, fixed effects model was used. Meta-regression and subgroup analyses were performed to explore the source of heterogeneity. Sensitivity analysis and publication bias were also tested.

RESULTS

A total of 11 studies with 27,585 participants were included in this analysis which indicated that there was an increased odd between diabetic neuropathy and osteoporosis (overall OR 2.20, 95% CI 1.71-2.83). In the subgroup analyses and meta-regression, diabetic neuropathy has no significant difference in osteoporosis or fracture (p = 0.532). And osteoporosis also has no significant difference in type 1 or type 2 diabetic neuropathy (p = 0.668).

CONCLUSIONS

This meta-analysis suggests that patients with diabetic neuropathy have a significantly increased chance of developing osteoporosis, even fragility fracture. The clinicians should pay more attention to the patients with diabetic neuropathy. Further studies were still needed to explore the confounding factors among studies and to elucidate the underlying biological mechanisms.

The haptoglobin 2-2 genotype is associated with cardiac autonomic neuropathy in type 1 diabetes: the RETRO HDLc study

AIM

The haptoglobin (Hp) 2-2 genotype has been shown to increase the risk of coronary artery disease, kidney dysfunction and mortality from cardiovascular and renal causes in type 1 diabetes (T1D). Similar associations, however, have not been observed in those without diabetes. As cardiac autonomic neuropathy (CAN) is a cardiovascular disease risk factor, we assessed the presence of an association between the Hp 2-2 genotype and CAN.

METHODS

The study included 216 individuals with childhood-onset T1D and 200 individuals with normal glucose tolerance (NGT) of similar age and gender distribution to their counterparts with T1D. CAN was assessed using an electrocardiogram as an abnormal, age-specific, heart rate response to deep breathing. Multivariable logistic regression models were used to assess the association between the Hp 2-2 genotype and CAN.

RESULTS

Compared with NGT, participants with T1D had a similar proportion of Hp 2-2 carriers (41.5% vs. 32.0%, p = 0.05) but a greater CAN prevalence (28.2% vs. 5.0%, p < 0.0001). In multivariable logistic regression models, those carrying the Hp 2-2 genotype had significantly higher odds of CAN compared with Hp 1-1 or Hp 2-1 carriers (OR = 2.27, p = 0.01). The presence of T1D (OR = 4.20, p = 0.0003), hypertension (OR = 2.08, p = 0.03), eGFR (OR = 0.98, p = 0.01) and WBC count (OR = 1.21, p = 0.02) were also associated with CAN. There was no T1D by Hp interaction (p = 0.92), although in stratified analyses, the Hp-CAN association was significant only in T1D.

CONCLUSIONS

The Hp 2-2 genotype was independently associated with greater odds of CAN in T1D though no definitive conclusions could be made in NGT.

Peripheral Neuropathy as a Component of Skeletal Disease in Diabetes

PURPOSE OF REVIEW

The goal of this review is to explore clinical associations between peripheral neuropathy and diabetic bone disease and to discuss how nerve dysfunction may contribute to dysregulation of bone metabolism, reduced bone quality, and fracture risk.

RECENT FINDINGS

Diabetic neuropathy can decrease peripheral sensation (sensory neuropathy), impair motor coordination (motor neuropathy), and increase postural hypotension (autonomic neuropathy). Together, this can impair overall balance and increase the risk for falls and fractures. In addition, the peripheral nervous system has the potential to regulate bone metabolism directly through the action of local neurotransmitters on bone cells and indirectly through neuroregulation of the skeletal vascular supply. This review critically evaluates existing evidence for diabetic peripheral neuropathy as a risk factor or direct actor on bone disease. In addition, we address therapeutic and experimental considerations to guide patient care and future research evaluating the emerging relationship between diabetic neuropathy and bone health.