Visit-to-visit variability of clinical risk markers in relation to long-term complications in type 1 diabetes

Long-term systolic blood pressure variability independent of mean blood pressure is associated with mortality and cardiovascular events: A systematic review and meta-analysis

The association between long-term systolic blood pressure variability (SBPV) and cardiovascular (CV) outcomes after being adjusted with mean blood pressure (BP) is questionable. This systematic review aims to evaluate the associations between mean BP adjusted long-term SBPV and CV outcomes. A systematic search was conducted on PubMed, Scopus, and Science Direct on January 4, 2023. A total of 9,944,254 subjects from 43 studies were included in this meta-analysis. Long-term SBPV increased the risk of all-cause mortality (HR 1.21 [95%CI 1.16-1.25], I2=100%), CV mortality (HR 1.10 [95%CI 1.07-11.4], I2 = 90%), MACE (HR 1.10 [1.07-1.13], I2 = 91%), cerebrovascular stroke (HR 1.22 [1.16-1.29], I2=100%), and myocardial infarction (HR 1.13 [95%CI (1.07-1.19)], I2=91%). European populations generally had higher risk compared to other continents. In conclusion, long-term SBPV is associated with all-cause mortality, CV mortality, MACE, MI, and stroke. Poor outcomes related to long-term SBPV seem more dominated by cerebrovascular than coronary events.

Higher HbA1c variability is associated with increased arterial stiffness in individuals with type 1 diabetes

BACKGROUND

Both long-term glycaemic variability and arterial stiffness have been recognized as cardiovascular risk factors. This study aims to investigate whether an association between these phenomena exists in individuals with type 1 diabetes.

METHODS

This cross-sectional study included 673 adults (305 men, 368 women) with type 1 diabetes and combined available retrospective laboratory data on HbA_1c from the preceding 10 years with outcome data on arterial stiffness and clinical variables from a comprehensive study visit. HbA_1c variability was calculated as adjusted standard deviation (adj-HbA_1c-SD), coefficient of variation (HbA_1c-CV) and average real variability (HbA_1c-ARV). As measures of arterial stiffness, carotid-femoral pulse wave velocity (cfPWV; n = 335) and augmentation index (AIx; n = 653) were assessed using applanation tonometry.

RESULTS

The study population had a mean age of 47.1 (± 12.0) years and a median duration of diabetes of 31.2 (21.2-41.3) years. The median number of HbA_1c assessments per individual was 17 (12-26). All three indices of HbA_1c variability were significantly correlated with both cfPWV and AIx after adjustment for sex and age (p < 0.001). In separate multivariable linear regression models, adj-HbA_1c-SD and HbA_1c-CV were significantly associated with cfPWV (p = 0.032 and p = 0.046, respectively) and AIx (p = 0.028 and p = 0.049, respectively), even after adjustment for HbA_1c-mean. HbA_1c-ARV was not associated with cfPWV or AIx in the fully adjusted models.

CONCLUSIONS

An association independent of HbA_1c-mean was found between HbA_1c variability and arterial stiffness, suggesting a need to consider multiple HbA_1c metrics in studies assessing cardiovascular risk in type 1 diabetes. Longitudinal and interventional studies are needed to confirm any causal relationship and to find strategies for reducing long-term glycaemic variability.

Baseline risk markers and visit-to-visit variability in relation to kidney outcomes - A post-hoc analysis of the PERL study

BACKGROUND

Baseline risk variables and visit-to-visit variability (VV) of systolic blood pressure (SBP), HbA_1c, serum creatinine, and uric acid (UA) are potential risk markers of kidney function decline in type 1 diabetes.

METHODS

Post-hoc analysis of a double-blind randomized placebo-controlled clinical trial investigating allopurinol's effect on iohexol-derived glomerular filtration rate (iGFR) in type 1 diabetes with elevated UA. Primary outcome was iGFR change over three years. Linear regression with backwards selection of baseline clinical variables was performed to identify an optimized model forecasting iGFR change. Furthermore, VVs of SBP, HbA_1c, serum creatinine, and UA were calculated using measurements from the run-in period; thereafter assessed by linear regression, with iGFR change as the dependent variable.

RESULTS

404 participants were included in the primary analyses. In the optimized baseline variable model, higher HbA_1c, SBP, iGFR, albuminuria, and heart rate, and mineralocorticoid receptor antagonist prescription were associated with greater iGFR decline. Higher VV of SBP was associated with greater iGFR decline (adjusted β (ml/min/1.73 m²/50 % increase): -0.79, p = 0.01).

CONCLUSIONS

We identified several risk markers for faster iGFR decline in a high-risk population with type 1 diabetes. While further research is needed, our results indicate possible new and clinically feasible measures to risk stratify for DKD in type 1 diabetes.

Predictors and determinants of albuminuria in people with prediabetes and diabetes based on smoking status: A cross-sectional study using the UK Biobank data

Background

Smoking is attributed to both micro- and macrovascular complications at any stage of metabolic deregulation including prediabetes. Current global diabetes prevention programmes appear to be glucocentric, and do not fully acknowledge the ramifications of cardiorenal risk factors in smokers and ex-smokers. A more holistic approach is needed to prevent vascular complications in people with prediabetes and diabetes before and after quitting.

Methods

A cross-sectional study was carried out on participants who agreed to take part in the UK Biobank dataset at the time of their first attendances between March 01, 2006, and December 31, 2010. Those who had their urinary albumin concentration (UAC) data available were included, and those who did not have this data, were excluded. A logistic regression model was fitted to explore the relationship between cardiorenal risk factors and albuminuria in people with prediabetes and diabetes, based on smoking status.

Findings

A total of 502,490 participants were included in the UK Biobank dataset. Of them, 30.4% (n=152,896) had their UAC level recorded. Compared with non-smokers, the odds of albuminuria in smokers with prediabetes and diabetes were 1.21 (95% CI 1.05 - 1.39, p=0.009), and 1.26 (95% CI 1.10 - 1.44, p=0.001), respectively. The odds declined after quitting in both groups, but it was not statistically significant (p>0.05). Each unit increase in HbA1c was associated with equivalent increased odds of albuminuria in current and ex-smokers, OR 1.035 (95% CI 1.030 - 1.039, p<0.001), and 1.026 (95% CI 1.023 - 1.028, p <0.001), respectively. Compared to females, male ex-smokers were at 15% increased odds of albuminuria. In ex-smokers, each unit increase in waist circumference was associated with 1% increased risk of albuminuria. Compared with the least deprived quintiles, the odds of albuminuria in the most deprived quintiles, in current and ex-smokers were identical, OR 1.18 (95% CI 1.04-1.324, p=0.010), and 1.19 (95% CI 1.11 - 1.27, p<0.001), respectively.

Interpretation

Male smokers are at a higher risk of albuminuria after smoking cessation. Monitoring waist circumference in quitters may identify those who are at a higher risk of albuminuria. Combining smoking cessation intervention in smokers with prediabetes in the current diabetes prevention programmes may offset post-cessation weight gain and reduce the risk of albuminuria.

Funding

University of Sheffield.

Visit-to-visit variability in albuminuria predicts renal function deterioration in patients with type 2 diabetes

Aims/Introduction

We aimed to study the predictive ability of visit‐to‐visit variability in albuminuria for changes in renal function in patients with type 2 diabetes mellitus.

Materials and Methods

The cohort study was carried out in a single medical center. In the model development cohort of 1008 subjects, we developed the albuminuria variability score (AVS) to evaluate the visit‐to‐visit variability in albuminuria, which was the percentage of the number of changes in the urine albumin : creatinine ratio ≥3.39 mg/mmol among all visit‐to‐visit urine albumin : creatinine ratio differences within an individual. Multivariate logistic regression was applied to predict the influence of AVS levels on the occurrence of study end‐points. In another independent validation cohort of 310 participants, survival analysis was carried out to evaluate the ability of AVS in predicting the study end‐point.

Results

In the model development cohort, a higher AVS was associated with higher adjusted odds of having a declined or rapidly declined estimated glomerular filtration rate (eGFR) trajectory (1.84, 95% confidence interval 1.23–2.76 and 5.70, 95% confidence interval 2.28–14.25, respectively), a resultant eGFR <60 mL/min/1.73 m² (2.61, 95% confidence interval 1.63–4.16) and a >40% decline in eGFR from baseline (6.44, 95% confidence interval 2.15–19.26). In the validation cohort, a higher AVS independently predicted a 5‐year decrease of >40% in eGFR to <60 mL/min/1.73 m² (adjusted hazard ratio 3.33, 95% confidence interval 1.10–10.05). Integrated discrimination index and concordance statistics showed that AVS significantly improved the predictive ability of the models.

Conclusions

Visit‐to‐visit variability in albuminuria can independently predict long‐term renal function deterioration in patients with type 2 diabetes mellitus. Further investigations are warranted to elucidate the potential clinical applications.