Non-invasive assessment of temporal changes in myocardial microvascular function in persons with type 2 diabetes and healthy controls.

BACKGROUND: Cardiac Rubidium-82 (82 Rb) positron emission tomography/computed tomography (PET/CT) provides a measure of the myocardial blood flow and the myocardial flow reserve, which reflects the function of both large epicardial arteries and the myocardial microcirculation. Knowledge on changes in the myocardial microvascular function over time is lacking. METHODS: In this cohort study, we recruited 60 persons with type 2 diabetes and 30 non-diabetic controls, in 2013; all free of overt cardiovascular disease. All underwent a cardiac 82 Rb PET/CT scan. In 2019, all survivors (n = 82) were invited for a repeated cardiac 82 Rb PET/CT scan using the same protocol, and 29 with type 2 diabetes and 19 controls participated. RESULTS: Median duration between visits was 6.2 years (IQR: 6.1-6.3). In the total cohort, the mean age was 66.4 years (SD: 9.3) and 33% were females. The myocardial flow reserve was lower in persons with type 2 diabetes compared to controls (p = 0.002) but there was no temporal change in the myocardial flow reserve in participants with type 2 diabetes: mean change: -0.22 (95% CI: -0.47 to 0.02) nor in controls: -0.12 (-0.49 to 0.25) or when comparing type 2 diabetes to controls: mean difference: -0.10 (95% CI: -0.52 to 0.31). The temporal reduction in stress-induced myocardial blood flow did not differ within the groups but was more pronounced in type 2 diabetes compared to controls: mean difference: -0.30 (95% CI: -0.55 to -0.04). CONCLUSION: The myocardial microvascular function was impaired in persons with type 2 diabetes compared to controls but did not change significantly in either of the groups when evaluated over 6 years.

Prevalence, Treatment, and Control Rates of Conventional and Ambulatory Hypertension Across 10 Populations in 3 Continents.

Hypertension is a major global health problem, but prevalence rates vary widely among regions. To determine prevalence, treatment, and control rates of hypertension, we measured conventional blood pressure (BP) and 24-hour ambulatory BP in 6546 subjects, aged 40 to 79 years, recruited from 10 community-dwelling cohorts on 3 continents. We determined how between-cohort differences in risk factors and socioeconomic factors influence hypertension rates. The overall prevalence was 49.3% (range between cohorts, 40.0%-86.8%) for conventional hypertension (conventional BP ≥140/90 mm Hg) and 48.7% (35.2%-66.5%) for ambulatory hypertension (ambulatory BP ≥130/80 mm Hg). Treatment and control rates for conventional hypertension were 48.0% (33.5%-74.1%) and 38.6% (10.1%-55.3%) respectively. The corresponding rates for ambulatory hypertension were 48.6% (30.5%-71.9%) and 45.6% (18.6%-64.2%). Among 1677 untreated subjects with conventional hypertension, 35.7% had white coat hypertension (23.5%-56.2%). Masked hypertension (conventional BP <140/90 mm Hg and ambulatory BP ≥130/80 mm Hg) occurred in 16.9% (8.8%-30.5%) of 3320 untreated subjects who were normotensive on conventional measurement. Exclusion of participants with diabetes mellitus, obesity, hypercholesterolemia, or history of cardiovascular complications resulted in a <9% reduction in the conventional and 24-hour ambulatory hypertension rates. Higher social and economic development, measured by the Human Development Index, was associated with lower rates of conventional and ambulatory hypertension. In conclusion, high rates of hypertension in all cohorts examined demonstrate the need for improvements in prevention, treatment, and control. Strategies for the management of hypertension should continue to not only focus on preventable and modifiable risk factors but also consider societal issues.

Global Changes in Food Supply and the Obesity Epidemic.

PURPOSE OF REVIEW: We explore how a global shift in the food system caused by global economic growth, increase in available food per capita and in food processing is a driver of the obesity epidemic. RECENT FINDINGS: Economic development in most areas of the world has resulted in increased purchasing power and available per capita food. Supermarkets and a growing fast-food industry have transformed our dietary pattern. Ultra-processed food rich on sugars and saturated fat is now the major source of energy in most countries. The shift in food supply is considered a major driver of the obesity epidemic and the increasing prevalence of accompanying complications, such as type 2 diabetes, cardiovascular disease and cancer. However, the global shift might also have direct effects on the increase in type 2 diabetes, cardiovascular disease and cancer, independently of overweight and obesity. The shift in the food supply is a major driver of the obesity epidemic.

Cardiac (82)Rb PET/CT for fast and non-invasive assessment of microvascular function and structure in asymptomatic patients with type 2 diabetes.

AIMS/HYPOTHESIS: Coronary flow reserve (CFR) and coronary artery calcium (CAC) represent functional and structural aspects of atherosclerosis. We examined the prevalence of reduced CFR and high CAC scores in three predefined groups of participants without known cardiovascular disease: (1) patients with type 2 diabetes and albuminuria; (2) patients with type 2 diabetes and normoalbuminuria; and (3) non-diabetic controls. METHODS: In a cross-sectional design, cardiac (82)Rb positron emission tomography/computed tomography was conducted in 60 patients with type 2 diabetes who were free of overt cardiovascular disease and who were stratified by normoalbuminuria (<30 mg/24 h) (n = 30; age [mean ± SD] 60.9 ± 10.1 years) and albuminuria (≥ 30 mg/24 h) (n = 30; age 65.6 ± 4.8 years), and in 30 healthy, non-diabetic controls (age 59.8 ± 9.9 years). RESULTS: In controls, normoalbuminuric and albuminuric patients, CFR was 3.0 ± 0.8, 2.6 ± 0.8 and 2.0 ± 0.5, respectively. Reduced CFR (<2.5) was observed in 16.7%, 40.0% and 83.3% of participants, respectively, and median (interquartile range) CAC scores were 0 (0-81), 36 (1-325) and 370 (152-1,025), respectively (p for trend <0.01). After adjustment, the difference in CFR and CAC between albuminuric patients and controls remained significant (p ≤ 0.001). There were trends towards lower CFR and higher CAC scores in normoalbuminuric patients vs controls (p ≤ 0.023) and towards higher CAC scores in albuminuric vs normoalbuminuric patients (p = 0.026). In multivariate regression analysis, a higher urinary albumin excretion rate (UAER) tended to predict reduced CFR in the total population (p = 0.045). When the CAC score was added, there was also a trend (p = 0.032) towards an inverse association with reduced CFR. CONCLUSIONS/INTERPRETATION: Type 2 diabetic patients who were free of overt cardiovascular disease had a high prevalence of coronary microvascular dysfunction, especially with concomitant albuminuria, suggesting a common microvascular impairment occurring in multiple microvascular beds. Prospective studies are needed to show the prognostic significance of this finding.

Can ambulatory blood pressure measurements substitute assessment of subclinical cardiovascular damage?

OBJECTIVE: We have previously demonstrated that markers of subclinical organ damage (SOD) improve cardiovascular risk prediction in healthy individuals. We wanted to investigate whether this additive effect of SOD was due to inaccurate blood pressure (BP) measurement or whether ambulatory BP (AMBP) added further to risk prediction. METHODS: In a population cohort of 1385 Danish individuals free of cardiovascular disease and diabetes, we recorded traditional risk factors, AMBP and pulse wave velocity (PWV), urine albumin/creatinine ratio (UACR), left ventricular mass index (LVMI) and carotid atherosclerotic plaques at baseline. A composite cardiovascular endpoint (CEP) consisting of cardiovascular death and nonfatal myocardial infarction and stroke was recorded in national registries. RESULTS: During a median follow-up of 12.8 years, a total of 119 CEPs occurred. In categorical analysis, presence of SOD as well as masked hypertension increased sensitivity of Systemic Coronary Risk Estimation from 73.9 to 89.1% (P < 0.001) and reduced specificity from 60.1 to 41.8% (P < 0.001). In continuous analysis, logUACR [hazard ratio = 1.20 (95% confidence interval [CI] 1.05-1.38), P = 0.009], atherosclerotic plaques [hazard ratio = 1.82 (95% CI 1.21-2.74), P = 0.004] and 24-h SBP [hazard ratio = 1.34 (95% CI 1.12-1.60), P = 0.002] but not logPWV or LVMI predicted CEP in a model with adjustments for age, sex, conventional BP, total cholesterol and smoking. Compared with a risk model using only traditional risk factors, adding PWV, UACR, plaques, LVMI and 24-h SBP increased C-index significantly from 0.76 to 0.79% and produced a net reclassification improvement of 23.3% (P = 0.001). CONCLUSION: UACR and plaques predicted cardiovascular events independently of AMBP and improved risk prediction.