The impact of prediabetes and diabetes on endothelial function in a large population-based cohort

BACKGROUND

Diabetes and prediabetes are well-recognized risk factors for cardiovascular disease (CVD) and are marked by vascular endothelial dysfunction (ED). However, there is a scarcity of thorough population-based studies examining ED in individuals with diabetes/prediabetes free from manifest CVD. Here, we examined the association between ED assessed by reactive hyperaemia index (RHI) in the finger and diabetes/prediabetes in a large middle-aged population cohort.

METHODS

Within the Malmö Offspring Study, following the exclusion of participants <30 years and participants with prevalent CVD, 1384 participants had complete data on all covariates. The RHI was calculated using pulse amplitude tonometry. ED was defined as RHI < 1.67. Multivariable logistic and linear regression models were conducted to investigate associations between ED and RHI with diabetes and prediabetes.

RESULTS

The study population had a mean age of 53.6 ± 7.6 years (53% women). In study participants with manifest diabetes (n = 121) and prediabetes (n = 514), ED was present in 42% and 25% respectively, compared to 23% in those with normal glucometabolic status. In multivariable logistic regression analyses, prevalent diabetes was significantly associated with ED (OR 1.95; 95%CI 1.57-3.39; p = 0.002), as well as with lower RHI (β-coeff. -0.087; p = 0.002). However, prediabetes showed no association with neither ED nor RHI.

CONCLUSION

In a population free from CVD, vascular endothelial dysfunction was primarily associated with manifest diabetes, but not with prediabetes, implying that finger ED may develop when diabetes is established, rather than being an early sign of glucose intolerance. Further research is needed to explore whether addressing glucose intolerance could potentially delay or prevent vascular ED onset.

The impact of age on endothelial dysfunction measured by peripheral arterial tonometry in a healthy population-based cohort - the Malmö offspring study

BACKGROUND/AIMS

The reactive hyperaemia index (RHI) assesses endothelial function, with a proposed cut-off of <1.67 for prevalent endothelial dysfunction (ED). However, uncertainties remain about whether this cut-off is age-dependent and applicable in healthy individuals. We aimed to explore ED in relation to age within a large population-based cohort of young to middle-aged, healthy individuals.

METHODS

Within the Malmö Offspring Study, a total of 1812 subjects (50.9% women, mean age 48 ± 11 years) were included. Post-occlusion/pre-occlusion ratio of the pulsatile signal amplitudes in the non-dominant upper arm was used to calculate RHI by EndoPat®. ED was defined as RHI < 1.67. Multivariable regression models were used to explore associations between ED and age.

RESULTS

Prevalent ED was found in 534 (29.5%) participants. In subjects aged ≤30 years, ED was present in 47.4% compared to 27.6% in subjects ≥30 years (p < 0.001). In multivariable logistic regression analyses, ED was associated with younger age (p < 0.001), higher BMI (p < 0.001) and current smoking (p < 0.001). No sex differences were observed.

CONCLUSION

In a large healthy population, RHI < 1.67, an early marker of endothelial dysfunction, was more prevalent in younger individuals, implying that RHI might not be a suitable measure of endothelial function in individuals under 30 years of age. Our findings suggest that low RHI in young, healthy individuals may not necessarily indicate true ED but rather an artefact of the limited ability of young and healthy arteries to dilate post-occlusion. Therefore, the term "pseudo-ED" may be applicable to young individuals with low RHI values.

Clinical routines for diabetes screening and treatment in cardiac rehabilitation improves detection and treatment of diabetes mellitus in patients with myocardial infarction

Background

Patients with myocardial infarction (MI) have a high prevalence of diabetes mellitus (DM). Prognosis in patients with MI and DM is substantially worse than for those without DM. An unacceptably high proportion of patients with DM remain both undiagnosed and undertreated despite follow-up at cardiac rehabilitation (CR) centres.

Purpose

Using nationwide survey and registry data to investigate associations of clinical routines for DM screening and treatment at CR centres in Sweden with detection and treatment of DM at one-year post-MI.

Methods

Data on CR clinical routines were derived from the Perfect-CR survey, evaluating structures and follow-up processes at CR centres in Sweden (n=78). The response rate was 100% and missing data was minimal. Clinical routines for DM screening and treatment during CR (exposures) included the following: 1) laboratory assessments of fasting glucose and/or HbA1c as a part of initial patient assessment by a nurse, 2) routine use of oral glucose tolerance test (OGTT), 3) joint case rounds with diabetologists, and 4) whether diabetes medication is adjusted by cardiologists. Patient baseline and outcome data was derived from the national quality registry SWEDEHEART (n=7549). Primary outcome was DM incidence at one-year post-MI. Secondary outcome was the proportion of patients receiving diabetes medication other than insulin (secondary outcome). The association between exposures (for each clinical routine and cumulatively [0–4 work routines]) and outcomes was estimated using unadjusted and adjusted logistic regression, adjusting for relevant covariates.

Results

Number (%) of CR centres applying each of the clinical routines is shown in Table 1. The most common routine applied was fasting glucose and/or HbA1c being routinely evaluated at initial patient assessment (n=48 (62%)), while the least common was CR centres having joint case rounds with diabetologists (n=7 (9%)). Twenty (26%) CR centres did not apply any of the clinical routines while 7 (9%) centres applied 3 or 4 routines. Unadjusted and adjusted odds ratios (OR) with 95% confidence intervals (CI) for incident DM are shown in Figure 1. Compared to not applying any routines, 1) applying one or more routines was positively associated higher DM incidence at one-year post-MI (p for trend in unadjusted and adjusted models &lt;0.001. Figure 1), and 2) at centres where all four working routines were applied, the odds for patients being treated with diabetes medication was significantly higher (crude OR 2.37 [1.80–3.13], adjusted OR 1.78 [1.19–2.66]).

Conclusion

Applying structured clinical routines for DM screening and treatment within CR can improve detection and treatment of DM in patients with MI

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The current study was supported by The Swedish Research Council for Health, Working Life and Welfare (FORTE, grant number 2019-00365); The Swedish Heart and Lung Association (grant number 20190431); The Swedish Heart and Lung Patient Organization; The Swedish Cardiology Society; The faculty of Medicine, Lund University, Sweden; Astra Zeneca; and Amgen.

Cerebral saturation is associated with physical activity and post-discharge mortality in heart failure patients

Background

The cross-sectional relationship between heart failure (HF) and cerebral oxygenation has been studied in the past but the prognostic significance of this relationship has been limited. Here, we aimed to assess the role of cerebral tissue oxygen saturation (SctO2) as a risk factor for HF mortality and rehospitalization as well as evaluate the association between SctO2 with physical activity in a Swedish prospective HF cohort.

Methods

Ninety-five patients hospitalized for HF (mean age 70 years; 21% women) were examined with near-infrared spectroscopy (NIRS) and screened for physical activity derived from questionnaires in the Swedish national public health survey. The median follow-up time to death and re-hospitalization was 1377 (interquartile range, 245–2392) and 293 (14–2363) days, respectively. Associations between SctO2 at rest, post-discharge mortality and re-hospitalization were analyzed using multivariable Cox regression analysis adjusted for age, sex, body-mass index, smoking, prevalence of atrial fibrillation, prevalence of diabetes and systolic blood pressure. The associations between SctO2 and self-reported physical activity were explored by using logistic regression analysis adjusted for the aforementioned risk factors.

Results

A total of 25 patients (26%) reported to be engaged in physical activity less than one hour throughout the week. In the fully adjusted Cox regression model, low SctO2 at rest was associated with post-discharge mortality (HR, 0.77; CI, 0.66–0.91; p=0.002). However, low SctO2 was not associated with post-discharge rehospitalization risk (HR, 0.94; CI, 0.88–1.01; p=0.092). In the fully adjusted logistic regression models, low SctO2 at rest was associated with decreased physical activity (&lt;1h per week), (OR 1.22; CI, 1.05–1.42; p=0.01).

Conclusion

We have demonstrated that low cerebral tissue oxygen saturation at rest is associated with post-discharge mortality in patients hospitalized for HF, independently of traditional risk factors. In addition, low cerebral tissue oxygen saturation at rest is associated with low physical activity. These findings highlight the role of cerebral saturation as a risk factor for cardiovascular prognosis, as well as underline the potential importance of taking cerebral perfusion into account when treating for heart failure.

Funding Acknowledgement

Type of funding sources: None.

Selenoprotein-P deficiency is associated with higher risk of incident heart failure

Background

Selenium deficiency has been associated with all-cause and cardiovascular mortality, incident cardiovascular disease (coronary artery disease, myocardial infarction and stroke), and with poor prognosis in patients with acute heart failure (HF). Furthermore, high selenium levels were recently shown to be associated with reduced mortality and reduced incidence of HF in non-smokers.

Purpose

To examine if selenoprotein-P (SELENOP), a main carrier protein of selenium, is associated with incident HF.

Methods

SELENOP concentrations were measured in 5060 randomly selected subjects from the population-based prospective cohort study “the Malmö Preventive Project” (n=18240) using a validated ELISA approach. After exclusion of subjects with prevalent HF (n=230), complete data on all co-variates was available in 4803 subjects (1400 women (29.1%), mean age 69.6±6.2 years, 885 (19.7%) current smokers). SELENOP was continously related to risk of incident HF using Cox regression models adjusted for age, sex, body mass index, systolic blood pressure, anti-hypertensive treatment, smoking status, diabetes status, low-density lipoprotein cholesterol levels, and prevalent coronary events. Further, subjects within the lowest SELENOP quintile were compared to subjects in the remaining four quintiles in an adjusted model.

Results

Each 1 SD increment in SELENOP levels was associated with lower risk of incident HF (n=436) during a median follow-up period of 14.7 years (interquartile range 10.9–15.7 years, hazard ratio (HR) 0.92, 95% confidence interval (95% CI) 0.84–0.99; p=0.049 in a model adjusted for cardiovascular risk factors. Multivariate quintile analyses revealed that the subjects in the lowest SELENOP quintile were at the highest risk of incident HF in an adjusted model (HR 1.46; 95% CI: 1.17–1.83 for incident HF; p for trend 0.039) illustrated in a Kaplan-Meier survival analysis (Figure 1). No interaction effect was seen for sex or smoking.

Conclusion

Low SELENOP levels are associated with a higher risk of incident HF supporting recent studies, which further emphasizes the need for randomly controlled trials to examine if supplementation with selenium improves prognosis.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Swedish Medical Research CouncilSwedish Society of Medicine

Biomarkers associated with prevalent hypertension and higher blood pressure in a population-based cohort: a proteomic approach

Background

Globally, hypertension represents an enormous health issue as it is a major, yet modifiable risk factor for developing cardiovascular disease. Recently, chitinase-3-like protein 1 (CHI3L1) was shown to be positively associated with the incidence of hypertension among prehypertensive subjects, and variants of CHI3L1 gene were associated with both CHI3L1-levels and hypertension.

Purpose

To explore associations between prevalent hypertension and blood pressure, and 92 proteins with involvement in inflammation and cardiovascular disease.

Methods

Plasma samples from 1713 individuals from a Swedish population-based cohort (mean age 67.3±6.0 years; 28.9% women) were analysed with a proximity extension assay panel, consisting of 92 proteins. Prior to all analyses, subjects with prevalent cardiovascular disease, defined as having a history of prevalent coronary or stroke event, were excluded (n=189). Univariate logistic regression models were carried out exploring associations between each of the 92 proteins and prevalent hypertension, defined as systolic blood pressure ≥140 mmHg and/or a diastolic blood pressure ≥90 mmHg, or use of antihypertensive treatment (n=1168, 76.4%). Bonferroni-corrected significant associations between proteins and hypertension were further analysed using stepwise selection of covariates, namely age, body mass index, diabetes status, and cystatin C, in logistic regression models. Proteins with significant adjusted associations with prevalent hypertension were further analysed for associations with systolic and diastolic blood pressure individually in stepwise linear regression models. Complete data on all variables were available in 1527 subjects.

Results

Sixteen proteins were significantly associated with prevalent hypertension in univariate analyses. After adjustment, three proteins remained significantly associated with prevalent hypertension (i.e., CHI3L1, low-density lipoprotein receptor (LDL receptor) and tissue plasminogen activator (tPA); Table 1). In analyses of associations with systolic blood pressure, CHI3L1 and LDL receptor showed significant associations. In analyses of associations with diastolic blood pressure, CHI3L1, LDL receptor and tPA showed significant associations (Table 1).

Conclusions

Higher CHI3L1, tPA and LDL receptor levels were positively associated with prevalent hypertension after multivariable adjustment, among 1527 elderly subjects without established cardiovascular disease. Furthermore, higher CHI3L and LDL receptor levels were positively associated with mean systolic, as well as mean diastolic blood pressure in multivariable analyses.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The Swedish Medical Research Council and The Swedish Heart and Lung Foundation

3044Exploration of biomarkers for subclinical atherosclerosis in an African population using a proteomics chip targeted at inflammation and cardiovascular disease

Introduction

The evolving use of multiplex proteomic platforms provides an excellent tool for investigating associations between multiple proteins and subclinical atherosclerotic disease. In this study, we evaluated the impact of a multiplex protein panel, on carotid intima-media thickness (cIMT) as a marker of subclinical atherosclerosis.

Purpose

We used a multiplex proteomic platform to identify possible associations between proteins and subclinical carotid atherosclerosis as measured by carotid ultrasound in an African population.

Methods

In the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study, 92 proteins from the Proseek Multiplex CVD III 96×96 (Olink Bioscience, Sweden) were analyzed in 378 participants (mean age 44.7±9.6 years, 50.6% women, 10.8% with known cardiovascular disease). Carotid ultrasound was performed for measurements of the carotid intima-media thickness (cIMT, mean 0.663±0.127 mm) and calculation of cross-sectional wall area (CSWA, mean 13.5±4.4mm2), a measure of target organ damage. Possible associations between the proteins, and cIMT and CSWA, respectively, were explored using linear regression models. A two-sided Bonferroni corrected P-value of 0.05/92=5.4x10–4 was considered statistically significant in the crude analysis.

Results

Of 18 proteins (1 standard deviation of change of ln-transformed values) that were Bonferroni-corrected (p≤5.4x10–4) significantly associated with cIMT and/or CWAS in crude analyses, the following remained significant after further adjustment for age, sex, waist circumference, systolic blood pressure, smoking and total cholesterol: growth-differentiation factor-15 (GDF15; β 0.017, p=0.050), E-selectin (SELE; β 0.019, p=0.017), carboxypeptidase A1 (CPA1; β 0.019, p=0.019), C-C motif chemokine 15 (CCL15; β 0.031, p<0.001), chitinase-3-like protein 1 (CHI3L1; β 0.021, p=0.007), the hemoglobin scavenger receptor (CD163; β 0.021, p=0.008) and osteoprotegerin (OPG; β 0.022, p=0.004). As for target-organ damage defined by CSWA, SELE (β 0.459, p=0.018), CCL15 (β 0.398; p=0.032) and CD163 (β 0.541, p=0.005) showed multivariate adjusted significant associations.

Conclusion

In an African population, we could confirm five proteins (GDF15, SELE, CHI3L1, CD163 and OPG) associated with cIMT, but in addition identified two proteins (CPA1 and CCL15) with novel associations with cIMT and/or CSWA.

Acknowledgement/Funding

North-West University; National Research Foundation (NRF); Medical Research Council (MRC-SA); Department of Education North-West Province; ROCHE

1444Metabolically healthy obesity (MHO) in the Malmo Diet Cancer Study - epidemiology and prospective risks

Background/Aims

Metabolically healthy obesity (MHO) is a controversial topic, since the underlying mechanisms and contributing factors behind this phenotype remain unclear. Here we aimed to investigate the characteristics of MHO, as well as prospective mortality risk.

Method

A cross-sectional analysis was carried out in a subsample of 3,812 obese subjects (BMI ≥30 kg/m2) selected from the Malmo Diet Cancer Study (MDCS) cohort (n=28,403). Subjects with MHO (n=1182; mean age 58±7 years) were defined by having no records of hospitalization in the national Swedish Hospital Discharge Register prior to the baseline examination, other than hospitalization due to normal deliveries or external injuries. MHO subjects were further compared to subjects with metabolically unhealthy obesity, MUO (n=2,630; mean age 60±7 years), and all non-obese individuals (n=24,591; mean age 58±8 years) in the cohort study. Moreover, prospective risk analyses for incident morbidity and mortality were carried out by Cox regression.

Results

Compared to MOU individuals (one-way ANOVA), MHO individuals were younger (58±7 years vs. 60±7 years, p=0.001) and more likely to be male (41.2% vs 37.1%, p=0.016). MHO individuals reported a significantly lower proportion of sedentary life style than MUO (17.4% vs. 21.9%, p=0.009), and were more likely to hold a university degree (13.4% vs. 9.4%, p=0.003). Furthermore, MHO individuals had significantly lower HbA1c (p=0.012), fasting plasma glucose (p=0.001) and triglyceride levels (p=0.011) as compared to their MOU counterparts. Cox-regression analysis adjusted for age, sex, smoking and blood pressure (follow-up time 20±6 years) showed both a significantly lower all-cause mortality risk for MHO individuals as compared to MUO (HR 0.74, 95% CI: 0.66–0.82; p=0.001), as well as lower total incident cardiovascular (CV) morbidity risk (HR 0.69, 95% CI: 0.60–0.80; p=0.001). Interestingly, when comparing MHO individuals to all non-obese individuals in the MDCS, there were no significant differences in neither mortality risk (p=0.9), nor incident CV morbidity risk (p=0.7).

All-cause mortality risk

Conclusion

Compared to MUO individuals, MHO individuals presented with a higher level of education- and physical activity together with a more favorable lipid- and glucose profile. MHO individuals were at significantly lower prospective risk of total- and cardiovascular mortality during 20-years follow-up, as compared to MOU individuals. Notably, no significant differences could be seen in mortality and CV morbidity risks when comparing MHO subjects to all non-obese individuals in the total cohort.

Acknowledgement/Funding

The Research Council of Sweden and Skane University Hospital Funds and Foundations (Sweden)