Cardiovascular mortality in non-insulin-dependent diabetes mellitus. A controlled study among 683 diabetics and 683 age- and sex-matched normal subjects

Precision prognostics for cardiovascular disease in Type 2 diabetes: a systematic review and meta-analysis

BACKGROUND

Precision medicine has the potential to improve cardiovascular disease (CVD) risk prediction in individuals with Type 2 diabetes (T2D).

METHODS

We conducted a systematic review and meta-analysis of longitudinal studies to identify potentially novel prognostic factors that may improve CVD risk prediction in T2D. Out of 9380 studies identified, 416 studies met inclusion criteria. Outcomes were reported for 321 biomarker studies, 48 genetic marker studies, and 47 risk score/model studies.

RESULTS

Out of all evaluated biomarkers, only 13 showed improvement in prediction performance. Results of pooled meta-analyses, non-pooled analyses, and assessments of improvement in prediction performance and risk of bias, yielded the highest predictive utility for N-terminal pro b-type natriuretic peptide (NT-proBNP) (high-evidence), troponin-T (TnT) (moderate-evidence), triglyceride-glucose (TyG) index (moderate-evidence), Genetic Risk Score for Coronary Heart Disease (GRS-CHD) (moderate-evidence); moderate predictive utility for coronary computed tomography angiography (low-evidence), single-photon emission computed tomography (low-evidence), pulse wave velocity (moderate-evidence); and low predictive utility for C-reactive protein (moderate-evidence), coronary artery calcium score (low-evidence), galectin-3 (low-evidence), troponin-I (low-evidence), carotid plaque (low-evidence), and growth differentiation factor-15 (low-evidence). Risk scores showed modest discrimination, with lower performance in populations different from the original development cohort.

CONCLUSIONS

Despite high interest in this topic, very few studies conducted rigorous analyses to demonstrate incremental predictive utility beyond established CVD risk factors for T2D. The most promising markers identified were NT-proBNP, TnT, TyG and GRS-CHD, with the highest strength of evidence for NT-proBNP. Further research is needed to determine their clinical utility in risk stratification and management of CVD in T2D.

Precision Prognostics for Cardiovascular Disease in Type 2 Diabetes: A Systematic Review and Meta-analysis

Background Precision medicine has the potential to improve cardiovascular disease (CVD) risk prediction in individuals with type 2 diabetes (T2D). Methods We conducted a systematic review and meta-analysis of longitudinal studies to identify potentially novel prognostic factors that may improve CVD risk prediction in T2D. Out of 9380 studies identified, 416 studies met inclusion criteria. Outcomes were reported for 321 biomarker studies, 48 genetic marker studies, and 47 risk score/model studies. Results Out of all evaluated biomarkers, only 13 showed improvement in prediction performance. Results of pooled meta-analyses, non-pooled analyses, and assessments of improvement in prediction performance and risk of bias, yielded the highest predictive utility for N-terminal pro b-type natriuretic peptide (NT-proBNP) (high-evidence), troponin-T (TnT) (moderate-evidence), triglyceride-glucose (TyG) index (moderate-evidence), Genetic Risk Score for Coronary Heart Disease (GRS-CHD) (moderate-evidence); moderate predictive utility for coronary computed tomography angiography (low-evidence), single-photon emission computed tomography (low-evidence), pulse wave velocity (moderate-evidence); and low predictive utility for C-reactive protein (moderate-evidence), coronary artery calcium score (low-evidence), galectin-3 (low-evidence), troponin-I (low-evidence), carotid plaque (low-evidence), and growth differentiation factor-15 (low-evidence). Risk scores showed modest discrimination, with lower performance in populations different from the original development cohort. Conclusions Despite high interest in this topic, very few studies conducted rigorous analyses to demonstrate incremental predictive utility beyond established CVD risk factors for T2D. The most promising markers identified were NT-proBNP, TnT, TyG and GRS-CHD, with the highest strength of evidence for NT-proBNP. Further research is needed to determine their clinical utility in risk stratification and management of CVD in T2D.

The Prevalence of Uncontrolled Hypertension among Patients Taking Antihypertensive Medications and the Associated Risk Factors in North Palestine: A Cross-Sectional Study

BACKGROUND

Uncontrolled hypertension (HTN) is a challenge for public health professionals all over the world. It is the leading and most important modifiable risk factor for coronary artery disease, congestive heart failure, stroke, renal diseases, and retinopathy. The aim of the present study was to estimate the prevalence of uncontrolled HTN among Palestinian hypertensive patients on treatment. In addition, the study aimed to explore the relationship between socio-demographic and clinical factors with HTN control as well as establish a comprehensive literature review for similar studies.

METHODS

A cross-sectional study was conducted. 218 hypertensive patients who met the inclusion criteria were included in the study.

RESULTS

HTN is not adequately controlled in over 60% of treated patients. Factors that were linked to uncontrolled HTN and were statistically significant as per this study were diabetes (p=0.010), high BMI (p=0.009), smoking (p < 0.0001), lower educational level (p=0.002), and monotherapy (p=0.004).

CONCLUSION

The results suggest that effective efforts on improving HTN control are strongly needed. The efforts need to target hypertensive patients who are also smokers, diabetics, having a low education level, and have a higher-than-normal BMI.

Cardiovascular and all-cause mortality in patients with type 2 diabetes mellitus in the MADIABETES Cohort Study: Association with chronic kidney disease

AIMS

To assess the prevalence of stage 3-5 chronic kidney disease (CKD) at baseline and to identify associated risk factors. To determine the effect of CKD and CKD stage according to estimated glomerular filtration rate (eGFR) and albuminuria categories on all-cause and cardiovascular mortality after a 5-year follow-up.

METHODS

Prospective cohort study of 3443 outpatients with type 2 diabetes mellitus.

RESULTS

The prevalence of CKD was 28.32% (95% CI, 26.84-29.86); and variables most strongly associated were: age >74 years (OR, 19.88; 95% CI, 12.89-30.68) and albuminuria (OR, 2.27; 95% CI, 1.72-3.00). During follow-up, 221 CKD patients (22.90%) died compared with 203 non-CKD patients (8.31%) (p<0.01). The adjusted HR of CKD for cardiovascular and all-cause mortality was 1.82 (95% CI, 1.36-2.44) and 2.11 (95% CI, 1.61-2.76) for those with LDL cholesterol =135 mg/dl, respectively. The adjusted HR of very-high-risk CKD for all-cause mortality was 4.44 (95% CI, 2.31-8.53) in aged <75 years and 1.80 (95% CI, 1.19-2.72) in aged ≥75 years.

CONCLUSIONS

CKD at baseline is an independent risk factor for all-cause and cardiovascular mortality in the overall cohort, men and women, or in primary and secondary prevention of coronary heart disease. Albuminuria is an independent risk factor for all-cause and cardiovascular mortality only in primary prevention.

The impacts of albuminuria and low eGFR on the risk of cardiovascular death, all-cause mortality, and renal events in diabetic patients: meta-analysis

BACKGROUND

Precise effects of albuminuria and low estimated glomerular filtration rate (eGFR) on cardiovascular mortality, all-cause mortality, and renal events in diabetic patients are uncertain.

MATERIALS AND METHODS

A systematic review was conducted of the literature through MEDLINE, EMBASE, and CINHAL from 1950 to December 2010. Cohort studies of diabetic patients providing adjusted relative risk (RR) of albuminuria and eGFR for risks of cardiovascular mortality, all-cause mortality, and renal events were selected. Two reviewers screened abstracts and full papers of each study using standardized protocol.

RESULTS

We identified 31 studies fulfilling the criteria from 6546 abstracts. With regard to the risk of cardiovascular mortality, microalbuminuria (RR 1.76, 95%CI 1.38-2.25) and macroalbuminuria (RR 2.96 95%CI 2.44-3.60) were significant risk factors compared to normoalbuminuria. The same trends were seen in microalbuminuria (RR 1.60, 95%CI 1.42-1.81), and macroalbuminuria (RR 2.64, 95%CI 2.13-3.27) for the risk of all-cause mortality, and also in microalbuminuria (RR 3.21, 95%CI 2.05-5.02) and macroalbuminuria (RR 11.63, 95%CI 5.68-23.83) for the risk of renal events. The magnitudes of relative risks associated with low eGFR along with albuminuria were almost equal to multiplying each risk rate of low eGFR and albuminuria. No significant factors were found by investigating potential sources of heterogeneity using subgroup analysis.

CONCLUSIONS

High albuminuria and low eGFR are relevant risk factors in diabetic patients. Albuminuria and low eGFR may be independent of each other. To evaluate the effects of low eGFR, intervention, or race, appropriately designed studies are needed.

Shadow of diabetes over cardiovascular disease: comparative quantification of population-attributable all-cause and cardiovascular mortality

BACKGROUND

We contrasted impacts on all-cause and cardiovascular disease (CVD) mortality of diabetes vs. CVD.

METHODS

Among participants the Tehran lipid and glucose study aged ≥ 30 years (n = 9752), we selected those who participated in the follow-up study until 20 March 2009 (n = 8795). Complete data on covariate were available for 8, 469 participants, contributing to a 67935 person-year follow up. In the analysis of outcomes (all-cause and CVD mortality), diabetes and CVD were assessed using Cox proportional hazard regression model adjusting for established CVD risk factors. We used population attributable hazard fraction (PAHF) and rate advancement period (RAP) that expresses how much sooner a given mortality rate is reached among exposed than among unexposed individuals.

RESULTS

Ten percent of the participants self-reported to have pervious CVD, and diabetes was ascertained in 17% of participants at baseline examination. During a median follow-up of 9 years 386 participants died of which 184 were due to CVD. All-cause and CVD mortality rate (95% CIs) were 5.5 (5.0-6.1) and 2.6 (2.3-3.0) per 1000 person-year, respectively. The PAHF of all-cause mortality for diabetes 9.2 (7.3-11.1) was greater than the one for CVD 3.5 (1.1-5.5). RAP estimates for all-cause mortality associated with diabetes ranged from 7.4 to 8.6 years whereas the RAP estimates for all-cause mortality associated with CVD ranged from 3.1 to 4.3 years. The PAHF of CVD mortality for diabetes 9.4 (6.8-12.0) was greater than the one for CVD 4.5 (1.8-7.0). RAP estimates for CVD mortality associated with diabetes ranged from 8.2 to 9.8 years whereas the RAP estimates for CVD mortality associated with CVD ranged from 4.7 to 6.7 years.

CONCLUSIONS

We demonstrated that diabetes, which was shown to be keeping pace with prevalent CVD in terms of conferring excess risk of incident CVD, is currently causing more deaths in the population than does CVD.

Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers and combined therapy in patients with micro- and macroalbuminuria and other cardiovascular risk factors: a systematic review of randomized controlled trials

BACKGROUND

A recent clinical trial showed harmful renal effects with the combined use of angiotensin-converting enzyme inhibitors (ACEI) and angiotensin-II receptor blockers (ARB) in people with diabetes or vascular disease. We examined the benefits and risks of these agents in people with albuminuria and one or more cardiovascular risk factors.

METHODS

MEDLINE, EMBASE and Renal Health Library were searched for trials comparing ACEI, ARB or their combination with placebo or with one another in people with albuminuria and one or more cardiovascular risk factor.

RESULTS

Eighty-five trials (21,708 patients) were included. There was no significant reduction in the risk of all-cause mortality or fatal cardiac-cerebrovascular outcomes with ACEI versus placebo, ARB versus placebo, ACEI versus ARB or with combined therapy with ACEI + ARB versus monotherapy. There was a significant reduction in the risk of nonfatal cardiovascular events with ACEI versus placebo but not with ARB versus placebo, ACEI versus ARB or with combined therapy with ACEI + ARB versus monotherapy. Development of end-stage kidney disease and progression of microalbuminuria to macroalbuminuria were reduced significantly with ACEI versus placebo and ARB versus placebo but not with combined therapy with ACEI + ARB versus monotherapy.

CONCLUSIONS

ACEI and ARB exert independent renal and nonfatal cardiovascular benefits while their effects on mortality and fatal cardiovascular disease are uncertain. There is a lack of evidence to support the use of combination therapy. A comparative clinical trial with ACE, ARB and its combination in people with albuminuria and a cardiovascular risk factor is warranted.

Metformin and reduced risk of hepatocellular carcinoma in diabetic patients with chronic liver disease

BACKGROUND

Previous studies have reported the association between type 2 diabetes mellitus (DM2) and hepatocellular carcinoma (HCC).

AIMS

To explore the relationships among DM2, antidiabetic therapy and HCC risk.

METHODS

We recruited 610 HCC patients compared with 618 matched cirrhotic patients and 1696 Controls. The odds ratio (OR) for HCC in diabetic subjects treated with insulin, sulphonylureas and metformin was calculated.

RESULTS

DM2 prevalence was 31.2% in HCC, 23.3% in cirrhotic patients and 12.7% in Controls (P<0.0001). The OR for HCC in diabetic HCC patients vs Controls was 3.12 [confidence interval (CI) 2.40-3.90; P<0.001] in univariate analysis and 2.50 (CI 1.70-3.69; P<0.0001) in multivariate analysis. Comparing diabetic HCC patients vs liver cirrhosis (LC) cases, univariate analysis showed an OR for HCC of 2.09 (CI 1.50-2.90; P<0.001), whereas on multivariate analysis we found an OR of 1.46 (CI 1.07-1.98; P=0.02). In 84% of the cases, type 2 diabetes mellitus has been present before the HCC diagnosis. Multivariate analysis showed that metformin treatment was associated with a strong and statistically significant reduction of the risk of HCC, as compared with the use of sulphonylureas or insulin, in diabetic HCC patients vs Controls and vs LC cases (OR of 0.15; CI 0.04-0.50; P=0.005 and OR=0.16; CI 0.06-0.46; P=0.0006 respectively).

CONCLUSIONS

Our study shows that DM2 is an independent risk factor for HCC and pre-exists to HCC occurrence. In DM2 patients with HCC, metformin therapy is associated with a reduced HCC risk and seems to have a protective effect on HCC development.

The genetic architecture of lipoprotein subclasses in Gullah-speaking African American families enriched for type 2 diabetes: the Sea Islands Genetic African American Registry (Project SuGAR)

We sought to partition the genetic and environmental influences on lipoprotein subclasses and identify genomic regions that may harbor genetic variants that influence serum lipoprotein levels in a sample of Gullah-speaking African-Americans. We genotyped 5,974 SNPs in 979 subjects from 418 pedigrees and used the variance component approach to compute heritability estimates, genetic and environmental correlations, and linkage analyses for selected lipoprotein subclasses. The highest heritability estimate was observed for large VLDL particle concentration (0.56 +/- 0.14). Mean LDL particle size and small LDL particle concentration (-0.94) had the strongest genetic correlation estimate. The highest logarithm of odds (LOD) score detected (3.0) was on chromosome 6p24 for small LDL particle concentration. The strongest signal, obtained with the reduced sample of diabetic individuals only, was observed on chromosome 20p13 for small LDL particle concentration. The highest bivariate linkage signal (LOD 2.4) was observed on chromosome 6p24 for mean LDL particle size and small LDL particle concentration. Our results suggest a significant genetic contribution to multiple lipoprotein subclasses studied in this sample and that novel loci on chromosomes 6, 10, 16, and 20 may harbor genes contributing to small, atherogenic LDL particle concentration and large, triglyceride-rich VLDL particle concentration.

Renal function and risk for cardiovascular events in type 2 diabetic patients with hypertension: the RENAAL and LIFE studies

OBJECTIVE

To investigate whether a threshold exists for cardiovascular risk in type 2 diabetic patients with hypertension, the association between renal function and cardiovascular risk was examined across the entire physiological range of serum creatinine.

DESIGN AND METHODS

The RENAAL and LIFE studies enrolled 1513 and 1195 patients with type 2 diabetes and hypertension, respectively. The relationship between baseline serum creatinine and the risk for a composite outcome of myocardial infarction, stroke or cardiovascular death was examined using Cox regression models. To adjust for heterogeneity between studies and treatment groups, these factors were included as strata when applicable. The analyses were conducted with adjustment for age, gender, smoking, alcohol use, blood pressure, heart rate, total and high-density lipoprotein (HDL) cholesterol, hemoglobin, albuminuria and prior cardiovascular disease.

RESULTS

The hazard ratios across the baseline serum creatinine categories < 0.9 mg/dl, 0.9-1.2 mg/dl, 1.2-1.6 mg/dl, 1.6-2.8 mg/dl and >or= 2.8 mg/dl were 0.51 (95% confidence interval 0.34, 0.74), 0.74 (0.55, 1.00), 1.00 (reference), 1.24 (0.96, 1.59) and 1.67 (1.17, 2.91), respectively. Baseline serum creatinine (per mg/dl) strongly predicted the composite cardiovascular endpoint in LIFE [2.82(1.74,4.56), P < 0.001], RENAAL [1.41(1.12,1.79), P < 0.001], as well as the combined studies [1.51(1.21,1.87), P < 0.001].

CONCLUSION

A progressively higher risk for the composite cardiovascular endpoint was observed with incremental baseline serum creatinine in type 2 diabetic patients with hypertension, even within the normal range. Thus, there appears to be no serum creatinine threshold level for an increased cardiovascular risk. Baseline serum creatinine was a major independent risk factor for cardiovascular disease (www.ClinicalTrials.gov number NCT00308347).

All-cause and cardiovascular mortality in diabetic subjects increases significantly with reduced estimated glomerular filtration rate (eGFR): 10 years' data from the South Tees Diabetes Mortality study

AIMS

To investigate the association between estimated glomerular filtration rate (eGFR) and total and cardiovascular mortality in a population-based cohort of diabetic subjects.

METHODS

A longitudinal study using a population-based district diabetes register comprising 3288 subjects in South Tees, UK. The eGFR was calculated using the Modification of Diet in Renal Disease (MDRD) study equation. Patients were stratified by baseline eGFR into five stages as per the National Kidney Foundation guidelines: Stage 1, eGFR > 90; Stage 2, eGFR 60-89; Stage 3, eGFR 30-59; Stage 4, eGFR 15-29; and Stage 5, eGFR < 15 ml/min per 1.73 m(2). Main outcome was all-cause and cardiovascular mortality between 1 January 1994 and 31 July 2004.

RESULTS

At baseline, mean age (58.4 years) differed between groups. Persons with lower eGFR were older (P < 0.001). Thirty-six percent (n = 1193, males 56%) had died by 10 years (cardiovascular cause in 60%). Median follow-up was 10.5 years amounting to 28 342 person years. Stages 4 and 5 (eGFR <or= 29 ml/min per 1.73 m(2)) were amalgamated for mortality analysis. Total and cardiovascular mortality increased with reduced eGFR. Adjusted hazard ratios (HR) [95% confidence interval (CI)] for all-cause mortality comparing groups 2 and 3, and 4 and 5 combined with group 1 were 1.28 (1.02, 1.60), 2.58 (2.05, 3.25) and 6.42 (4.25, 9.71), respectively. Adjusted HRs (95% CI) for mortality due to circulatory disease comparing groups 2 and 3, and 4 and 5 combined with group 1 were 1.50 (1.10, 2.06), 3.32 (2.41, 4.58) and 7.99 (4.69, 13.62), respectively.

CONCLUSIONS

In diabetic subjects, mortality increases significantly with reduced GFR. Low eGFR identifies patients at high risk of cardiovascular mortality who should be targeted for aggressive risk factor modification.

Prediction of cardiovascular and total mortality in Chinese type 2 diabetic patients by the WHO definition for the metabolic syndrome

AIM

The aim of this study is to investigate the prevalence of metabolic syndrome (MES) in type 2 diabetic patients and the predictive values of the World Health Organization (WHO) and National Cholesterol Education Programme (NCEP) definitions and the individual components of the MES on total and cardiovascular mortality.

METHODS

A prospective analysis of a consecutive cohort of 5202 Chinese type 2 diabetic patients recruited between July 1994 and April 2001.

RESULTS

The prevalence of the MES was 49.2-58.1% depending on the use of various criteria. There were 189 deaths (men: 100 and women: 89) in these 5205 patients during a median (interquartile range) follow-up period of 2.1 (0.3-3.6 years). Of these, 164 (87%) were classified as cardiovascular deaths. Using the NCEP criterion, patients with MES had a death rate similar to those without (3.51 vs. 3.85%). By contrast, based on the WHO criteria, patients with MES had a higher mortality rate than those without (4.3 vs. 2.4%, p = 0.002). Compared to patients with neither NCEP- nor WHO-defined MES, only the group with MES defined by the WHO, but not NCEP, criterion had significantly higher mortality rate (2.6 vs. 6.8%, p < 0.001). Using Cox regression analysis, only age, duration of diabetes and smoking were identified as independent factors for cardiovascular or total death. Among the various components of MES, hypertension, low BMI and albuminuria were the key predictors for these adverse events.

CONCLUSIONS

In Chinese type 2 diabetic patients, the WHO criterion has a better discriminative power over the NCEP criterion for predicting death. Among the various components of the MES defined either by WHO or NCEP, hypertension, albuminuria and low BMI were the main predictors of cardiovascular and total mortality.

Proteinuria is a prognostic marker for cardiovascular mortality: NIPPON DATA 80, 1980-1999

BACKGROUND: Proteinuria has been considered to be a prognostic marker for persons with diabetes mellitus, but only a limited number of studies about the relationship between proteinuria and mortality among general population has been available.

METHODS: The subjects were 10,897 individuals who participated in the National Cardiovascular Survey conducted in 1980 and who were aged 30 years or older living in 300 districts that had been randomly selected throughout Japan. The vital records were confirmed in 1999 and 7,203 subjects (3,180 males and 4,023 females) without a history of hypertension, stroke, heart disease, renal disease, or diabetes mellitus at the start of the study were investigated.

RESULTS: There were 126,825 person-years of follow-up. During the observed period of time, 371 died of cardiovascular causes, including 171 stroke deaths and 74 coronary deaths. The risk of proteinuria for cardiovascular mortality was greater than unity for those with a normal serum creatinine level, after adjusting for age and other cardiovascular disease risk factors.

CONCLUSIONS: When contrasted with other cardiovascular disease risk factors, urinary protein is an independent risk factor for cardiovascular death among the Japanese population.

Relationship between albuminuria and cardiovascular disease in Type 2 diabetes

Impaired renal function and albuminuria, common among people with type 2 diabetes, are strong predictors of atherosclerotic cardiovascular events. However, the relationships among albuminuria and measures of calcified atherosclerotic plaque are unknown. Coronary and carotid artery calcified plaque were measured using fast-gated helical computed tomography, and B-mode ultrasonography measured common carotid artery intima-medial thickness (IMT) in 588 white participants with type 2 diabetes from 325 families ascertained for the presence of multiple siblings with type 2 diabetes. Measured risk factors included age, gender, BP, body mass index, GFR, glycosylated hemoglobin, LDL cholesterol, HDL cholesterol, smoking, and medications that affect urine albumin:creatinine ratio (ACR). Generalized estimating equations with exchangeable correlation and the sandwich estimator of the variance were used to test for an association among coronary artery calcified plaque, carotid artery calcified plaque, carotid IMT, and ACR while adjusting for measured risk factors. Participants had a mean +/- SD (median) age of 61.2 +/- 9.2 yr (61.0 yr), ACR of 106.2 +/- 590 mg/g (12.9 mg/g), GFR of 93.3 +/- 33.2 ml/min (87.4 ml/min), coronary artery calcium mass score of 1394 +/- 2685 (323), carotid artery calcium mass score of 295 +/- 652 (51), and IMT of 0.66 +/- 0.12 mm (0.65 mm). Adjusting for the measured covariates, ACR was strongly and positively associated with coronary artery calcium (P = 0.004) and carotid artery calcium (P = 0.0004). Albuminuria is strongly associated with calcified plaque in the coronary and carotid arteries in white individuals with type 2 diabetes and relatively preserved renal function.

Mild renal insufficiency as a cardiovascular risk factor in non-proteinuric type II diabetes

OBJECTIVES

To evaluate cardiovascular risk according to baseline renal function in a group of non-proteinuric type II diabetic patients.

MATERIAL AND METHODS

Prospective study with a follow-up of 423 non-proteinuric type II diabetic patients with creatinine <150 micromol/l for an average of 4.7 years (S.D. 1.55). Creatinine clearance (CC) was estimated using the Cockcroft-Gault formula and expressed in millilitre per minute. The hazard ratio (HR) associated with each millilitre per minute decrease in baseline CC on fatal or non-fatal cardiovascular events and total mortality was evaluated using the Cox regression model.

RESULTS

Baseline creatinine was 89 micromol/l (S.D. 15.9) and CC was 69.5 ml/min (S.D. 20). There were 63 cardiovascular events (15 unstable angina, 10 non-fatal myocardial infarctions, 25 non-fatal strokes, two amputations, nine fatal myocardial infarctions and two fatal strokes) and 39 total deaths (11 for cardiovascular causes). The cardiovascular event rate was 31.7/1000 patient-years and the total mortality rate was 19.6/1000 patient-years. The independent predictors of cardiovascular events were: CC (HR=1.035; confidence interval (CI) 95% 1.02-1.05; P<0.0001), total cholesterol/HDL cholesterol ratio (HR=1.25; CI 95% 1.1-1.4; P=0.0008), baseline coronary heart disease (HR=2.05; CI 95% 1.07-3.9; P=0.04) and baseline microalbuminuria (HR=2.3; CI 95% 1.3-3.8; P=0.003). The independent total mortality predictors were: CC (HR=1.04; CI 95% 1.02-1.08; P<0.0001), male (HR=2.1; CI 95% 1.1-4; P=0.027) and baseline microalbuminuria (HR=2.1; CI 95% 1.1-4;P=0.03).

CONCLUSIONS

Mild renal insufficiency increases cardiovascular risk in non-proteinuric patients with type II diabetes.

A structured review of the relationship between microalbuminuria and cardiovascular events in patients with diabetes mellitus and hypertension

STUDY OBJECTIVE

To quantify the relative risk of cardiovascular events associated with microalbuminuria in patients with both diabetes mellitus and hypertension.

DESIGN

A structured literature search from January 1990-December 2002 using MEDLINE, IPA, and CINAHL.

MEASUREMENTS AND MAIN RESULTS

We identified original studies that reported the presence or absence of microalbuminuria and estimates of risk associated with cardiovascular events in patients with both diabetes and hypertension. Abstracted information consisted of study design, patient demographics and risk factors, treatment regimens, and outcome variables. Point estimates and confidence intervals for relative risk were calculated from available data. Of 651 citations identified and reviewed based on title and abstract, 72 were selected for full review. Seven met the inclusion criteria. Because of lack of homogeneity among studies, the results were not conducive to pooling. Cardiovascular end points associated with the presence of microalbuminuria in these studies were all-cause mortality, cardiovascular mortality, and composite cardiovascular morbidity. The relative risk of cardiovascular end points associated with the presence of microalbuminuria ranged from 1.6 (95% confidence interval [CI] 1.2-2.2) to 7.9 (95% CI 2.5-25.3).

CONCLUSION

From the limited information available, the risk of cardiovascular events and mortality is estimated to be 2-8 times higher when microalbuminuria is present in patients with diabetes and hypertension. Point estimates in relative risk of cardiovascular morbidity and mortality in patients with diabetes and hypertension were generally higher compared with studies estimating risk in those with only diabetes. Studies that examine the relationship between microalbuminuria (scaled as a continuous or ordinal variable) and cardiovascular events are necessary to clarify potential benefits of pharmacotherapies that reduce levels of urinary albumin.

Comparative effects of Irbesartan on ambulatory and office blood pressure: a substudy of ambulatory blood pressure from the Irbesartan in Patients with Type 2 Diabetes and Microalbuminuria study

OBJECTIVE

Irbesartan was renoprotective independently of its blood pressure-lowering effect in the Irbesartan in Patients With Type 2 Diabetes and Microalbuminuria (IRMA2) study. However, blood pressure was evaluated by trough office blood pressure (OBP), which may underestimate reductions in 24-h ambulatory blood pressure (ABP). In the present study, we evaluated 24-h blood pressure patterns in a subpopulation of the IRMA2 trial.

RESEARCH DESIGN AND METHODS

Type 2 diabetic patients (n = 43) with persistent microalbuminuria (as determined by repeated overnight measurements of urinary albumin excretion [UAE]) and hypertension who were included in the IRMA2 study at the Steno Diabetes Center were subjected to 24-h ABP (Takeda, TM2420) measurements before and 2 years after randomization to placebo (n = 15), irbesartan 150 mg daily (Irb150; n = 13), or irbesartan 300 mg daily (Irb300; n = 15).

RESULTS

At baseline, the placebo, Irb150, and Irb300 groups were comparable: OBP: 157 +/- 15/89 +/- 7, 156 +/-15/91 +/- 11, and 159 +/- 16/90 +/- 9 mmHg (NS); 24-h ABP: 148 +/- 13/83 +/- 11, 148 +/- 16/82 +/- 7 and 147 +/- 16/81 +/- 10 mmHg (NS); and UAE (geometric mean with 95% CI): 43 (32-57), 46 (30-70), and 59 (42-85) micro g/min (NS), respectively. We found that 2 years after randomization, OBP was significantly reduced in all three groups (by 11/7, 13/8, and 13/8 mmHg in the placebo, Irb150, and Irb300 groups, respectively), but that there were no significant differences among groups. Reductions in 24-h ABP were similar in the three groups (11/10, 5/7, and 7/8 mmHg, respectively; NS), as were reductions in day ABP (11/9, 7/7, and 8/9 mmHg, respectively; NS) and night ABP (4/11, 7/7, and 3/3 mmHg, respectively; NS). The reduction in UAE at the end of the study was 0% (-86 to 42), 38% (-14 to 66), and 73% (59 to 82), respectively (overall, P < 0.01).

CONCLUSION

Irbesartan is renoprotective independently of its beneficial effect in lowering 24-h blood pressure in patients with type 2 diabetes and persistent microalbuminuria.

Transvascular low-density lipoprotein transport in patients with diabetes mellitus (type 2): a noninvasive in vivo isotope technique

OBJECTIVE

The increased risk of atherosclerosis associated with diabetes cannot be explained by conventional cardiovascular risk factors alone. We hypothesized that transvascular lipoprotein transport may be increased in patients with diabetes, possibly explaining increased intimal lipoprotein accumulation and, thus, atherosclerosis.

METHODS AND RESULTS

We developed an in vivo method for measurement of transvascular transport of low density lipoprotein (LDL) and applied it in 16 patients with maturity-onset diabetes (type 2) and 29 healthy control subjects. Autologous 131I-labeled LDL was reinjected intravenously in addition to 125I-labeled albumin, and the 1-hour fractional escape rates were taken as indices of transvascular transport. Both parameters were normally distributed, and they were tightly correlated (R2=0.69, P<0.0001). Transvascular LDL transport was 5.4+/-2.9%/h and 4.1+/-1.5%/h in patients with diabetes and control subjects, respectively (P<0.05); equivalent values for albumin were 6.5+/-2.5%/h and 5.3+/-1.6%/h (P<0.05). This difference most likely was not caused by altered hepatic LDL receptor expression, glycosylation of LDL, small LDL size, nephropathy, statin use, or different plasma insulin levels in diabetic patients.

CONCLUSIONS

Transvascular LDL transport may be increased in patients with type 2 diabetes. This suggests that lipoprotein flux into the arterial wall is increased in people with diabetes, possibly explaining the accelerated development of atherosclerosis.