The impact of diabetic retinopathy on long-term outcome following coronary artery bypass graft surgery

Evaluation of Cerebral Vasomotor Reactivity by Transcranial Doppler Ultrasound in Patients with Diabetic Retinopathy

The aim of this study was to assess the correlation between cerebral vasomotor reactivity (CVR) and the grade of diabetic retinopathy. A total of 43 diabetic patients with matched severity of diabetic retinopathy between their right and left eyes were included in this study. Diabetic retinopathy was graded in three groups. Right and left middle cerebral artery CVR was assessed by the breath-holding index (BHI) using transcranial Doppler ultrasound (TCD). The mean age of the patients was 56.51 ± 9.34 years with a mean duration of having diabetes mellitus of 14.49 ± 8.06 years. Diabetic retinopathy was graded as mild, moderately severe, and severe in 27.9%, 34.9%, and 37.2% of the patients, respectively. The grade of diabetic retinopathy was associated with the HbA1c level (p < .049), microalbuminuria (p < .024), and BHI (p = .001). In patients with severe diabetic retinopathy, the right-sided BHI was significantly lower as compared to those with mild or moderately severe retinopathy (p = .001 and p = .008, respectively). The left-sided BHI value in patients with severe diabetic retinopathy was significantly lower as compared to those with mild or moderately severe retinopathy (p = .001 and p = .012, respectively). In subjects with moderately severe diabetic retinopathy, both-sided BHI was significantly reduced compared to those with mild retinopathy (p = .001). Our results indicate that the grade of diabetic retinopathy was associated with impaired CVR.

Predominant peripheral lesions in patients with diabetic retinopathy and its association with systemic comorbidities

Purpose:

To determine the associations of predominant peripheral lesions (PPLs) with systemic comorbidities in individuals with diabetic retinopathy.

Methods:

This is a multicenter cross-sectional observational study conducted across three tertiary eye care centers in south India between January 2019 and July 2021. Ultra-widefield fundus images of consecutive patients with varying severity of diabetic retinopathy with data on systemic comorbidities were classified based on the presence or absence of PPL. Systemic comorbidities (hypertension, diabetic kidney disease, coronary artery disease, dyslipidemia, and anemia) were compared between the two groups.

Results:

A total of 879 participants (70.1% males) were included in the study, of which 443 (50.4%) patients had PPL. The mean age of the study participants was 56 ± 10 years, mean age of onset of diabetes was 41.24 ± 11.6 years, and mean duration of diabetes was 15.39 ± 7.6 years. The number of PPL increased with increasing severity of DR. Of all the systemic comorbidities analyzed, we found that coronary artery disease (CAD) had a significant association with PPL (Odds ratio [OR]-1.69; 95% confidence interval [CI], 1.12–2.55; P = 0.013) after adjusting for diabetic retinopathy severity, duration of diabetes, and age of onset of diabetes.

Conclusion:

The presence of PPL is a marker for coronary artery disease and early referral to cardiology is warranted.

Diabetic Retinopathy May Be a Predictor of Stroke in Patients With Diabetes Mellitus

BACKGROUND

It is unclear whether diabetic retinopathy (DR) can be a predictor of stroke. In this research context, the objective of our study was to investigate whether there is a significant association between DR and stroke in diabetic patients by meta-analysis.

METHODS

After a systematic search of studies in electronic databases, we screened all studies reporting the risk of DR status and stroke incidence and calculated their odds ratios (ORs) and hazard ratios (HRs). The effects of type of diabetes and severity of DR were also considered for subgroup analysis.

RESULTS

We included 19 studies involving 45 495 patients. A pooled HR = 1.62 (1.28-2.06) were found for the risk of DR and stroke in diabetic patients. In a subgroup analysis performed on the type of diabetes, the results showed a significant association between stroke incidence and DR status in patients with type 2 diabetes (T2D) (OR: 1.78; 95% CI, 1.53-2.08), but this association was not conclusive in type 1 diabetes (T1D) (OR: 1.77; 95% CI, 0.48-6.61). The results of the subgroup analysis with diabetes severity showed that both mild and moderate nonproliferative diabetic retinopathy (NPDR) status and severe NPDR and worse status significantly increased the risk of stroke with HRs of 2.01 (1.45-2.78) and 2.27 (1.52-3.39), respectively.

CONCLUSION

DR status in diabetic patients is associated with an increased risk of stroke. This correlation was robust in patients with T2D, but uncertain in T1D. Based on this result, we have perhaps found the new factor for stroke management, so we analyzed the necessity and advantages of considering DR as a factor for stroke screening and risk management in our studies.

Association of Diabetic Retinopathy With Stroke: A Systematic Review and Meta-Analysis

Background: The population-based studies conducted thus far do not provide conclusive evidence of the link between diabetic retinopathy (DR) and stroke. The aim of the present systematic review was to determine whether DR is specifically associated with stroke.

Methods: MEDLINE, Embase, and Web of Science were systematically searched from their inception to July 31, 2020. All cohort studies that reported associations between the presence of DR and incident stroke were included. The pooled hazard ratios (HRs), pooled risk ratios (RRs), and 95% confidence intervals (CIs) were calculated.

Results: The meta-analysis included 19 cohort studies involving 81,452 diabetic patients. The pooled effect size of any DR related to stroke was 1.25 for HR (95% CI: 1.12–1.39; P < 0.0001) and 1.96 for RR (95% CI: 1.60–2.39; P < 0.0001). Subgroup analysis for the type of diabetes yielded pooled HR of 1.29 (95% CI: 1.10–1.50; P = 0.001) in patients with type 2 diabetes mellitus (T2DM). The pooled RR was 2.29 (95% CI: 1.77–2.96; P < 0.0001) in patients with T2DM. Two studies addressed the DR-related stroke among type 1 diabetes mellitus (T1DM) patients. One study found a significant association between DR and stroke (OR: 1.6; 95% CI: 1.1–2.3; P < 0.01), while the other did not identify an association between these two conditions (RR: 1.40; 95% CI: 0.62–2.18; P = 0.178).

Conclusions: The presence of DR is associated with an increased risk of stroke in diabetic patients. This correlation is robust in T2DM patients but uncertain in T1DM patients. Our findings indicate that DR is an important biomarker for the prediction of stroke. To further validate the role of DR in stroke-risk stratification, additional research is required on the association between the stage of DR and stroke risk, and more studies including T1DM patients are necessary.

Diabetic retinopathy predicts cardiovascular mortality in diabetes: a meta-analysis

BACKGROUND

The prognostic significance of diabetic retinopathy (DR) for cardiovascular diseases (CVD) remained unclear. Therefore, we performed this meta-analysis to assess whether DR predicted CVD mortality in diabetic patients.

METHODS

We searched PubMed, Embase, Web of Science and Cochrane Library for cohort studies reporting the association of DR and CVD mortality. Then we pooled the data for analysis.

RESULTS

After screening the literature, 10 eligible studies with 11,239 diabetic subjects were finally included in quantitative synthesis. The pooled risk ratio (RR) of DR, mild DR, and severe DR for CVD mortality was 1.83 (95% confidence interval (CI): 1.42, 2.36; p < 0.001), 1.13 (95% CI 0.81, 1.59; p = 0.46), and 2.26 (1.31, 3.91; p = 0.003), respectively, compared to those without DR. In type 2 DM, the patients with DR had a significantly higher CVD mortality (RR: 1.69; 95% CI 1.27, 2.24; p < 0.001). Subgroup analysis also showed a significantly higher CVD mortality in DR according to various regions, study design, data source, and follow-up period (all RR > 1; all P values < 0.05). Data from 2 studies showed no significant correlation of DR and CVD mortality in diabetic patients receiving cardiovascular surgery (RR: 2.40; 95% CI 0.63, 9.18; P = 0.200).

CONCLUSIONS

DR is a risk marker of cardiovascular death, and severe DR predicts a doubled mortality of CVD in diabetes. These findings indicate the importance of early identification and management of diabetic patients with DR to reduce the risk of death.

Prediction of risk of diabetic retinopathy for all-cause mortality, stroke and heart failure: Evidence from epidemiological observational studies

To examine and quantify the potential relation between diabetic retinopathy (DR) and risk of all-cause mortality, stroke and heart failure (HF).The resources of meta-analysis of epidemiological observational studies were from Pub-med, EMBASE, CINAHL, Cochrane Library, conference, and proceedings.Random/fixed effects models were used to calculate pooled subgroup analysis stratified by different grades of DR was performed to explore the potential source of heterogeneity. Statistical manipulations were undertaken using program STATA.Of the included 25 studies, comprising 142,625 participants, 19 studies were concluded to find the relation of DR to all-cause mortality, 5 for stroke, and 3 for HF. Risk ratio (RR) for all-cause mortality with the presence of DR was 2.33 (95% CI 1.92-2.81) compared with diabetic individuals without DR. Evidences showed a higher risk of all-cause mortality associated with DR in patients with T2D or T1D (RR 2.25, 95% CI 1.91-2.65. RR 2.68, 95% CI 1.34-5.36). According to different grades of DR in patients with T2D, RR for all-cause mortality varied, the risk of nonproliferative diabetic retinopathy (NPDR) was 1.38 (1.11-1.70), while the risk of proliferative diabetic retinopathy (PDR) was 2.32 (1.75-3.06). There was no evidence of significant heterogeneity (Cochran Q test P = 0.29 vs 0.26, I = 19.6% vs 22.6%, respectively). Data from 5 studies in relation to DR and the risk of stroke showed that DR was significantly associated with increased risk of stroke (RR = 1.74, 95%CI: 1.35-2.24), compared with patients without DR. Furthermore, DR (as compared with individuals without DR) was associated with a marginal increased risk of HF in patients with diabetes mellitus (DM) (n = 3 studies; RR 2.24, 95% CI 0.98-5.14, P = 0.056).Our results showed that DR increased the risk of all-cause mortality, regardless of the different stages, compared with the diabetic individuals without DR. DR predicted increased risk of stroke and HF. Although only 3 studies about HF were available, the association between DR and HF should be careful.

Prospective Association between Diabetic Retinopathy and Cardiovascular Disease-A Systematic Review and Meta-analysis of Cohort Studies

BACKGROUND

Diabetic retinopathy (DR) is linked to increased risk of cardiovascular (CV) disease. However, the effect size of the association was not consistent. In this study, we performed a systematic review and meta-analysis of available cohort studies to determine the association between DR and CV disease, and to investigate the factors that influence the association.

METHODS

Terms related to DR and CV disease were searched from MEDLINE and EMBASE database. High-quality articles (Newcastle-Ottawa scales above 6) conducted in cohort studies reporting the association between DR and CV disease were identified. Study-specific estimates were pooled using random effects with inverse variance meta-analysis. Subgroup analysis was performed according to diabetes types. Heterogeneity of included studies was assessed using the I(2) test. The cause of the heterogeneity was examined using metaregression analyses.

RESULTS

A total of 13 studies representing 17,611 patients without CV disease at baseline were included. At follow-up, there were 1457 CV disease-related incidences. Overall, DR was associated with increased risk of CV disease (relative risk [RR]: 2.42, 95% confidence interval [CI]: 1.77-3.31) in diabetes. Specifically, the RR was 3.59 (95% CI: 1.79-7.20) for type 1 diabetes and 1.81 (95% CI: 1.47-2.23) for type 2 diabetes. Significant heterogeneity was found in studies with type 1 diabetes. Metaregression analysis showed that baseline systolic blood pressure was a key factor leading to the heterogeneity.

CONCLUSION

In conclusion, DR is significantly associated with CV disease incidence and CV disease-related mortality in diabetes. Patients with DR may need more intensive management to control future CV disease attacks.

Diabetes complications and adverse health outcomes after coronary revascularization

AIMS

To examine effects of diabetes complications on health outcomes following coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI), comparing outcomes for patients with diabetes complications to those without diabetes complications.

METHODS

Retrospective analysis of discharge data for 61,566 patients with diabetes age 45 or older who had CABG or PCI in 2007 in United States community hospitals, using data from the Nationwide Inpatient Sample. Analysis included propensity score-adjusted logistic regression.

RESULTS

Of all patients, 21.2% of the weighted sample had diabetes complications. Older patients, Blacks and Hispanics, and those with greater illness severity were more likely to have diabetes complications. Unadjusted rates of in-hospital mortality, postoperative stroke, and renal failure were higher for patients with diabetes complications (rate ratios 2.2, 1.8, and 9.8, respectively; all p<0.0001). In adjusted results, having diabetes complications was associated with higher odds of in-hospital mortality (odds ratio, OR 1.62, 95% confidence interval, CI 1.37-1.91) and renal failure (OR 3.03, CI 1.71-5.39). Compared to CABG, PCI was associated with extra risk of postoperative renal failure for those with diabetes complications.

CONCLUSION

Among patients with diabetes having revascularization, those with diabetes complications have higher risks of in-hospital death and renal failure irrespective of having CABG or PCI.

Impact of diabetic retinopathy on late cardiac events after percutaneous coronary intervention

BACKGROUND

Diabetic retinopathy has been identified as a predictor of cardiovascular events and heart failure in patients with diabetes mellitus (DM). This study aimed to assess the impact of diabetic retinopathy on the incidence of late cardiac events following percutaneous coronary intervention.

METHODS

We enrolled 88 consecutive DM patients who underwent elective percutaneous coronary intervention and whose ophthalmologic records were available. Patients were divided into 2 groups: those with diabetic retinopathy (DR+ group; n=47), and those without diabetic retinopathy (DR- group; n=41). We examined the incidence of major adverse cardiac events (MACE) including cardiac death, myocardial infarction, and acute heart failure requiring emergency admission over a period of up to 5 years.

RESULTS

Patients in the DR+ group were likely to have a lower estimated glomerular filtration rate. Kaplan-Meier analysis showed that the event-free survival rates for all MACE, myocardial infarction, and heart failure were significantly lower in the DR+ group than in the DR- group (p=0.002, p=0.025, and p=0.022, respectively). Multivariate Cox proportional hazards analysis indicated that the presence of DR was a significant predictor of MACE (hazard ratio: 8.7; 95% CI: 1.1-69.8, p=0.042).

CONCLUSION

The presence of DR might be a useful predictor of late cardiac events following percutaneous coronary intervention.

[Aspects of perioperative care in patients with diabetes]

Diabetes is a common disease in Germany. Due to diabetes-associated end-organ disease, such as large and small vessel disease and neuropathy, diabetic patients require more intense anesthesia care during the perioperative phase. An in-depth and comprehensive medical history focusing on hemodynamic alterations, gastroparesis, neuropathy and stiff joint syndrome is a cornerstone of perioperative care and may affect outcome of diabetes patients more than specific anesthetic medications or the anesthetic procedure. Intraoperative anesthetic care needs to focus on preservation of hemodynamic stability, perioperative infection control and maintenance of glucose homeostasis. Whereas some years ago strict glucose control by aggressive insulin therapy was adamantly advocated, the results of recent studies have put the risk of such therapeutic algorithms into perspective. Therefore, optimized perioperative care of diabetic patients consists of setting a predefined targeted blood glucose level, evidence-based therapeutic approaches to reach that goal and finally adequate and continuous monitoring and amendment of the therapeutic approach if required.

Relationship between coronary artery disease and retinopathy in patients with type 2 diabetes mellitus

OBJECTIVE

To examine risk factors for coronary artery disease (CAD) and retinopathy in patients with type 2 diabetes mellitus (DM) and assess the relationship between CAD and retinopathy.

METHODS

A total of 1,003 outpatients with type 2 DM (578 men and 425 women) were classified into two groups according to the presence (based on ischemic findings on a resting electrocardiogram or a history of angina or myocardial infarction) or absence of CAD and four retinopathy stages based on the International Clinical Classification of Diabetic Retinopathy.

RESULTS

Stepwise multiple regression analyses showed that independent risk factors for CAD were age, the triglyceride (TG) level and smoking, while those for retinopathy included age, age of DM diagnosis, the HbA1c level and a female gender. The prevalence of CAD increased in association with the progression of retinopathy (p<0.01).

CONCLUSION

Since it is difficult to distinguish macrovascular and microvascular diseases, diabetic vascular disorders require comprehensive approaches to assessment and treatment.

Diabetic retinopathy predicts all-cause mortality and cardiovascular events in both type 1 and 2 diabetes: meta-analysis of observational studies

OBJECTIVE

The prognostic significance of diabetic retinopathy (DR) for death and cardiovascular (CV) outcomes is debated. We investigated the association of DR with all-cause mortality and CV events in patients with diabetes by a systematic review and meta-analysis.

RESEARCH DESIGN AND METHODS

The electronic databases Medline and Embase were searched for cohort studies that evaluated DR in type 2 or type 1 diabetic patients and reported total mortality and/or fatal and nonfatal CV events, including myocardial infarction, angina pectoris, coronary artery bypass graft, ischemic changes on a conventional 12-lead electrocardiogram, transient ischemic attack, nonfatal stroke, or lower leg amputation. Data extraction was performed by two reviewers independently. Pooled effect estimates were obtained by using random-effects meta-analysis.

RESULTS

The analysis included 20 studies that fulfilled the inclusion criteria, providing data from 19,234 patients. In patients with type 2 diabetes (n = 14,896), the presence of any degree of DR increased the chance for all-cause mortality and/or CV events by 2.34 (95% CI 1.96-2.80) compared with patients without DR. In patients with type 1 diabetes (n = 4,438), the corresponding odds ratio was 4.10 (1.50-11.18). These associations remained after adjusting for traditional CV risk factors. DR was also predictive of all-cause mortality in type 2 diabetes (odds ratio 2.41 [1.87-3.10]) and type 1 diabetes (3.65 [1.05-12.66]).

CONCLUSIONS

The presence of DR was associated with an increased risk of all-cause mortality and CV events in both type 2 and type 1 diabetic patients.

Eye complications and markers of morbidity and mortality in long-term type 1 diabetes

The incidence of type 1 diabetes is rising all over the world. Furthermore, the increased life-expectancy of type 1 diabetic patients is likely to cause a higher number of diabetes-related micro- and macrovascular complications in the years to come. In order to examine the level of long-term complications in type 1 diabetes as well as potential markers of micro- and macroangiopathy, a population-based cohort of Danish type 1 diabetic patients was examined in order to achieve the following aims: 1. To evaluate diabetic retinopathy as a long-term marker of all-cause mortality in type 1 diabetes (Paper I). 2. To estimate the long-term incidence and associated risk factors of blindness (Paper II) and cataract surgery (Paper III) in type 1 diabetes. 3 To use retinal vascular analyses in order to investigate the associations of long-term micro- and macrovascular complications and retinal vascular diameters (Paper IV) and retinal fractals (Paper V) in type 1 diabetes. 4. To examine N-terminal pro brain natriuretic peptide (Paper VI) and osteoprotegerin (Paper VII) as non-invasive markers of micro- and macrovascular complications in type 1 diabetes. In Paper I it was a major finding that, despite a mean age of only 38.3 years at baseline, 44.7% of the patients died during the 25-year follow-up. Patients who had proliferative retinopathy as well as proteinuria at the baseline examination had a significantly higher mortality. For these, the 10-year survival was only 22.2%. As demonstrated in Paper II, blindness is an important issue in type 1 diabetes. The 25-year cumulative incidence of blindness was 7.5%. Glycaemic regulation and maculopathy at baseline were both identified as risk factors of blindness. Finally, mortality was higher in patients who went blind during the follow-up. Cataract surgery is quite common in type 1 diabetes. In Paper III a 25-year cumulative incidence of 20.8% was found. Adjusted for mortality, this was even higher (29.4%). As compared to patients without diabetes, cataract surgery takes place approximately 20 years earlier in type 1 diabetic patients. Age and maculopathy at baseline were both identified as predictors of cataract surgery. In Paper IV it was demonstrated that patients with retinal arteriolar narrowing were 2.17 and 3.17 times more likely to have nephropathy and macrovascular disease, respectively. This was an important finding that suggests that retinal fundus photos may be used in order to predict the risk of non-ophthalmological complications in type 1 diabetes. Retinal fractal analysis is another way to evaluate the vascular system of the retina. In Paper V we found associations between retinal fractal and microvascular - but not macrovascular--disease. For instance, patients with lower fractal dimensions were more likely to have proliferative retinopathy (OR 1.45, 95% CI 1.04-2.03) and neuropathy (OR 1.42, 95% CI 1.01-2.01). NT-proBNP is likely to be a future predictor of diabetes-related complications. In Paper VI higher levels of NT-proBNP were related to nephropathy (OR 5.03, 95% CI 1.77-14.25), neuropathy (OR 4.08, 95% CI 1.52-10.97) and macrovascular disease (OR 5.84, 95% CI 1.65-20.74). These associations should be confirmed in future prospective studies. As opposed to NT-proBNP, osteoprotegerin is less likely to be a predictor of either micro- or macrovascular disease in type 1 diabetes. As demonstrated in Paper VII, even though association between higher levels of OPG and nephropathy were found in an age- and sex-adjusted model (OR 2.54, 95% CI 1.09-5.90), this was no longer statistically significant when other factors were taken into account. Overall, it was demonstrated that various complications such as mortality, blindness and cataract surgery were high in type 1 diabetes. Furthermore, retinal arteriolar narrowing, decreased retinal fractals and plasma NT-proBNP were associated with various micro- and macrovascular complications. If confirmed by prospective studies, these modalities may be used in order to identify patients at risk of diabetes-related complications. This could, ultimately, lead to decreased mortality and morbidity in type 1 diabetic patients.

Anesthetic considerations in diabetic patients. Part I: preoperative considerations of patients with diabetes mellitus

Diabetes mellitus is an increasingly common disease that affects people of all ages, resulting in significant morbidity and mortality. Diabetic patients require perioperative care more frequently than their nondiabetic counterparts. The major risk factors for diabetics undergoing surgery are the associated end-organ diseases: cardiovascular disease, autonomic neuropathy, joint collagen tissue, and immune deficiency. Physicians need to pay extra attention to preoperative and preprocedure evaluation and treatment of these diseases to ensure optimal perioperative management.

Detecting occult coronary artery disease followed by early coronary artery bypass surgery in patients with diabetic retinopathy: report from a diabetic retinocoronary clinic

OBJECTIVES

We hypothesized that a large number of patients with diabetic retinopathy who could benefit greatly from early coronary artery bypass grafting would not be identified.

METHODS

Patients with diabetic retinopathy receiving ophthalmologic care as outpatients in our hospital in whom coronary artery disease was not previously suspected were referred randomly to the diabetic retinocoronary clinic and were asked to participate in diagnostic tests, including an exercise treadmill test and exercise thallium scintigraphy or coronary computed tomography. Patients who had type 1 diabetes mellitus, required hemodialysis, or both were excluded from this study. A definitive diagnosis of coronary artery disease was confirmed by means of coronary angiography.

RESULTS

Of 214 patients with diabetic retinopathy, 55 (25.7%) were confirmed as having significant stenotic coronary artery disease. Patients with angiographically confirmed coronary disease were older than those with negative results on diagnostic tests (62.2 + or - 9.8 vs 57.9 + or - 10.3 years, P = .01). Fifteen had 1-vessel disease, 17 had 2-vessel disease, 14 had 3-vessel disease, 1 had left main trunk plus 1-vessel disease, 2 had left main trunk plus 2-vessel disease, and 5 had left main trunk plus 3-vessel disease. Eight patients had left main trunk disease, and 18 patients with non-left main trunk disease had proximal left anterior descending coronary artery (LAD) disease. Forty-two patients showed indications of coronary revascularization (coronary artery bypass grafting in 17 and percutaneous coronary intervention in 25). During the entire follow-up (287.6 + or - 183.2 days) of 39 patients undergoing coronary revascularization, all were alive without myocardial infarction, but 8 experienced vitreous hemorrhage.

CONCLUSIONS

Approximately 25% of patients with diabetic retinopathy receiving ophthalmologic care as outpatients have a significant stenotic coronary artery disease. Of the total diabetic population, a large number of patients with diabetic retinopathy who show strong indications for early coronary artery bypass grafting might well go unrecognized.

Elevated preoperative hemoglobin A1c level is associated with reduced long-term survival after coronary artery bypass surgery

BACKGROUND

The predictive role of hemoglobin A1c (HbA1c) on long-term outcomes after coronary artery bypass surgery has not been evaluated.

METHODS

Preoperative HbA1c levels were obtained in 3,201 patients undergoing primary, elective coronary artery bypass surgery at Emory Healthcare Hospitals from January 2002 to December 2006 and entered prospectively into a computerized database. Long-term survival status was determined by cross-referencing patient records with the Social Security Death Index. Log-rank (unadjusted) and Cox proportional hazards regression models (adjusted) were employed to determine whether HbA1c and diabetes mellitus were independent risk factors for reduced long-term survival, adjusted for 29 covariates. Hazard ratios for each unit increase in continuous HbA1c were calculated.

RESULTS

Patients with HbA1c of 7% or greater had lower unadjusted 5-year survival compared with patients with HbA1c less than 7% (p = 0.001). Similarly, patients with diabetes mellitus had lower unadjusted 5-year survival compared with patients without diabetes (p < 0.001). After multivariable adjustment, higher HbA1c (measured as a continuous variable) was associated with reduced long-term survival for each unit increase in HbA1c (hazard ratio 1.15, p < 0.001), but preoperative diagnosis of diabetes was not associated with reduced long-term survival after coronary artery bypass surgery (p = 0.41). Other multivariable predictors of reduced long-term survival included age, cerebrovascular disease, elevated serum creatinine, renal insufficiency, congestive heart failure, previous myocardial infarction, chronic lung disease, and peripheral vascular disease.

CONCLUSIONS

Poor preoperative glycemic control, as measured by an elevated HbA1c, is associated with reduced long-term survival after coronary artery bypass surgery. Optimizing glucose control in these patients may improve long-term survival.

In early-stage diabetic retinopathy, risk of cardiac events after implantation of sirolimus-eluting stent is higher than after coronary artery bypass surgery

BACKGROUND

Patients with diabetic retinopathy (DR) have an increased risk of death from coronary heart disease and myocardial infarction. The purpose of this study was to compare the outcomes of revascularization strategies (sirolimus-eluting stent [SES] and coronary artery bypass surgery [CABG]) in patients with DR according to the stage of retinopathy: non-proliferative retinopathy (NPDR) and proliferative retinopathy (PDR).

METHODS

From April 2004 until February 2007, 627 patients including 51 NPDR and 62 PDR patients underwent SES implantation. For each retinopathy group, a historical comparison group at the same stages of retinopathy undergoing CABG was selected. Cardiac events were defined as a composite of cardiac death, myocardial infarction, and repeat revascularization.

RESULTS

The average follow-up from the time of the initial revascularization was 27.7 ± 8.5 months for NPDR-SES patients, 69.6 ± 36.6 months for NPDR-CABG patients, 26.4 ± 9.7 months for PDR-SES patients, and 68.3 ± 44.2 months for PDR-CABG patients; and Kaplan-Meier estimates of the percentages of events at 24 months were 47.0%, 22.8%, 28.5%, and 26.0%. Kaplan-Meier curves for cardiac events differed significantly between the SES group and the CABG group in NPDR patients (p = 0.04), whereas the curves did not differ significantly between the two groups of PDR patients. The adjusted hazard ratio of SES implantation for cardiac events in the entire group of DR patients was 1.75 (95% confidence interval [CI] 1.02-3.00, p = 0.04).

CONCLUSIONS

SES implantation is not a suitable method of revascularization in DR patients, especially in NPDR patients. CABG may become the first-choice revascularization technique for these patients.

Proliferative retinopathy and proteinuria predict mortality rate in type 1 diabetic patients from Fyn County, Denmark

AIMS/HYPOTHESIS

We evaluated the effect of diabetic retinopathy on 25 year survival rate among a population-based cohort of type 1 diabetic patients from Fyn County, Denmark.

METHODS

In 1973 all diabetic patients from Fyn County, Denmark with onset before the age of 30 years as of 1 July 1973 were identified (n=727). In 1981, only 627 patients were still alive and resident in Denmark. Of these, 573 (91%) participated in a clinical baseline examination, in which diabetic retinopathy was graded and other markers of diabetes measured. Mortality rate was examined in a 25 year follow-up and related to the baseline examination.

RESULTS

Of the 573 patients examined at baseline in 1981 and 1982, 297 (51.8%) were still alive in November 2006. Of the others, 256 (44.7%) had died, three (0.5%) had left Denmark and 17 (3%) were of unknown status. Age- and sex-adjusted HRs of mortality rate were 1.01 (95% CI 0.72-1.42) and 2.04 (1.43-2.91) for patients with non-proliferative and proliferative retinopathy respectively at baseline compared with patients with no retinopathy. After adjusting for proteinuria, HR among patients with proliferative retinopathy lost statistical significance, but still remained 1.48 (95% CI 0.98-2.23). The 10 year survival rate of patients who had proliferative retinopathy as well as proteinuria at baseline was 22.2% and significantly lower (p<0.001) than in patients with proteinuria only (70.3%), proliferative retinopathy only (79.0%) or neither (86.6%).

CONCLUSIONS/INTERPRETATION

Proliferative retinopathy and proteinuria predict mortality rate in a population-based cohort of type 1 diabetic patients. In combination they act even more strongly. Non-proliferative diabetic retinopathy did not affect survival rate.

Predictors of in-stent restenosis and patient outcome after percutaneous coronary intervention in patients with diabetes mellitus

Diabetics have a significantly higher incidence of major adverse cardiac events (MACEs) and in-stent restenosis (ISR) than nondiabetics after percutaneous coronary intervention (PCI). Predictors of MACEs and ISR are uncertain in diabetics. In recent studies, microalbuminuria and proliferative retinopathy have been believed to relate to progressive coronary atherosclerosis. We retrospectively studied 191 consecutive patients (mean age 65 +/- 9 years) with diabetes who underwent PCI to determine predictors of ISR and MACEs (defined as cumulative incidence of myocardial infarction, revascularization, or death from cardiovascular cause), with special reference to microalbuminuria and proliferative retinopathy. Of 191 patients, 106 (56%) had a follow-up coronary angiogram at 16 +/- 2 months. Of these 106 patients, 66 (62%) developed ISR. In the multivariate model, microalbuminuria or proliferative retinopathy did not achieve significant association with ISR. Serum high-density lipoprotein cholesterol levels were significantly associated with a lower incidence of ISR (odds ratio [OR] 0.928, 95% confidence interval [CI] 0.876 to 0.983, p = 0.011) and MACEs (OR 0.96, 95% CI 0.931 to 1.000, p = 0.048). Use of drug-eluting stents also had a negative association with ISR (OR 0.171, 95% CI 0.05 to 0.585, p = 0.004). Renal insufficiency was associated with higher MACEs (OR 3.19, 95% CI 1.45 to 7.031, p = 0.0039). In conclusion, serum high-density lipoprotein cholesterol levels were inversely associated with ISR or MACEs.

Sight-threatening retinopathy is associated with lower mortality in type 2 diabetic subjects: a 10-year observation study

AIMS

To study associations between diabetic retinopathy and development of stroke, myocardial infarction and death in type 2 diabetic patients.

METHODS

During a 10-year observation period, 363 type 2 diabetic patients (diagnosis > or =30 years of age) attending an outpatient clinic were studied regarding the prevalence and incidence of retinopathy and associated risk factors, i.e., (HbA(1c), blood pressure, albuminuria, plasma creatinine, age, sex and diabetes duration) in relation to the development of myocardial infarction, stroke and death. The degree of retinopathy was classified as no retinopathy, background or sight-threatening retinopathy, i.e., clinically significant macular edema, severe non-proliferative or proliferative retinopathy.

RESULTS

During the study period, 62 patients had had myocardial infarction, 54 stroke and 99 patients died. Patients with sight-threatening retinopathy at baseline (n=41) had a 2.2-fold increased (p<0.01) risk for death compared to patients with no or background retinopathy, even when controlled for medical risk factors. When adjusted for medical risk factors, patients with no retinopathy at baseline (n=226) who remained without retinopathy or developed background retinopathy (n=187) during the study period, had a 3.6-fold increased risk for death (95% CI, 1.1, 11.8), (p=0.03), compared to patients who developed sight-threatening retinopathy (n=39), while the incidence of myocardial infarction did not differ. More patients who developed sight-threatening retinopathy were treated with ACE inhibitors than patients who did not (41% versus 24%; p=0.03).

CONCLUSION

Despite more medical risk factors, patients who developed sight-threatening retinopathy had lower mortality compared to patients with no or background retinopathy at follow-up. More patients who developed sight-threatening retinopathy were treated with ACE inhibitors but this seemed not to have influenced the lower mortality rate in this group, whereas the use of ACE inhibitors in patients who did not develop sight-threatening retinopathy was connected with lower mortality rate.

Diabetic retinopathy and coronary implantation of sirolimus-eluting stents

INTRODUCTION

The prognostic value of identifying the retinal status of diabetic patients undergoing coronary implantation of drug-eluting stents is unknown.

METHODS

We evaluated the outcomes of 318 consecutive patients undergoing implantation of sirolimus-eluting stents for coronary artery disease. Patients were divided into 5 groups according to the diabetic and retinal status: diabetic patients without retinopathy (43 patients); diabetic patients with nonproliferative retinopathy (34); diabetic patients with proliferative retinopathy (37); diabetic patients with unknown retinal status (30); and nondiabetic patients (174).

RESULTS

During a mean follow-up of 385 days, 64 patients had target-vessel failure (defined as a composite of death from cardiac causes, myocardial infarction, and target-vessel revascularization). At 1 year, Kaplan-Meier estimates of the rate of target-vessel failure were 15.3% for diabetic patients without retinopathy, 56.6% for those with nonproliferative retinopathy, 17.3% for those with proliferative retinopathy, 19.0% for those with unknown retinal status, and 16.0% for nondiabetic patients. After adjustment for the potential confounders and differences between groups, the relation of nonproliferative retinopathy to target-vessel failure remained significant. In an analysis in which diabetic patients without retinopathy were used as the reference group, the hazard ratios for target-vessel failure were 3.9 for those with nonproliferative retinopathy, 1.3 for those with proliferative retinopathy, 1.1 for those with unknown retinal status, and 1.4 for nondiabetic patients (P for trend = 0.015).

CONCLUSIONS

As compared with diabetic patients without retinopathy, those with nonproliferative retinopathy have an increased risk for target-vessel failure after coronary implantation of sirolimus-eluting stents.

Retinal arteriolar narrowing and left ventricular remodeling: the multi-ethnic study of atherosclerosis

OBJECTIVES

This study sought to examine the relationships of retinal vascular signs with left ventricular (LV) mass, volume, and concentric remodeling.

BACKGROUND

Microvascular disease, reflected as retinopathy lesions, has been shown to predict clinical congestive heart failure. Whether these retinal vascular changes are related to early structural alterations and remodeling of the heart in asymptomatic individuals is unknown.

METHODS

A cross-sectional, population-based study of 4,593 participants ages 45 to 85 years, free of clinical cardiovascular disease. Retinal vascular calibers and retinopathy were graded from retinal photographs according to standardized protocols. The LV mass and volume were measured from cardiac magnetic resonance imaging. Extent of LV concentric remodeling was determined by the ratio of LV mass to end-diastolic volume (M/V ratio).

RESULTS

After controlling for age, gender, race, center, past and current systolic blood pressure, body mass index, smoking, antihypertensive medications, diabetes, diabetes duration, glycosylated hemoglobin, lipid profile, and C-reactive protein, narrower retinal arteriolar caliber was associated with concentric (highest quintile of M/V ratio) remodeling (odds ratio [OR] 2.06, 95% confidence interval 1.57 to 2.70). This association was seen in men and women, and was present even in those without diabetes, without hypertension, and without significant coronary calcification. In multivariate analysis, the presence of retinopathy (OR 1.31, 95% confidence interval 1.08 to 1.61) was also associated with concentric remodeling.

CONCLUSIONS

Narrower retinal arteriolar caliber is associated with LV concentric remodeling independent of traditional risk factors and coronary atherosclerotic burden, supporting the hypothesis that microvascular disease may contribute to cardiac remodeling.

The beneficial effect of coronary-artery-bypass surgery on survival in patients with diabetic retinopathy

OBJECTIVE

The presence of retinopathy is a predictor of mortality following coronary revascularization in diabetics. We studied whether revascularization by coronary-artery-bypass surgery (CABG), as compared with percutaneous coronary intervention (PCI), influences the prognosis in diabetics with retinopathy.

METHODS

Between April 1996 and March 2004, 1489 patients underwent revascularization as an initial procedure. Among these a total of 319 diabetics underwent retinal examination prior to the initial revascularization. These patients were classified according to whether they had retinopathy and whether they had undergone CABG, either initially or after PCI. Mortality rates were estimated from the time of initial revascularization procedure.

RESULTS

The average follow-up from the time of initial revascularization was 48.2+/-28.6 months. In 153 diabetics with retinopathy, 59 eventually underwent CABG. During the entire follow-up period, there were 2 (3.4%) deaths in diabetics with retinopathy who underwent CABG and 14 (14.9%) deaths in those who did not have CABG. Mortality curves differed significantly between the two groups (P = 0.007). After adjustment for risk factors, the relative risk of death was 0.13 afforded by CABG (95% CI, 0.03-0.62; P = 0.011). In 166 diabetics without retinopathy, mortality curves were similar between the patients who underwent CABG and those who did not have CABG (P = 0.94).

CONCLUSIONS

CABG conferred a survival advantage in diabetics with retinopathy. In contrast, no survival advantage was evident in diabetics without retinopathy undergoing CABG. Retinal status should be taken into consideration when considering revascularization strategy for diabetics who have coronary artery disease.

Impact of Diabetic Retinopathy on Cardiac Outcome After Coronary Artery Bypass Graft Surgery: Prospective Observational Study

BACKGROUND

Diabetic retinopathy is a manifestation of more severe diabetes. We sought to assess the impact of diabetic retinopathy on cardiac outcome of coronary artery bypass graft surgery (CABG).

METHODS

We prospectively assessed the status of the retina of 74 consecutive diabetics who were referred for first-time CABG, and compared cardiac outcome of CABG in diabetics with retinopathy with that in those without retinopathy. Cardiac events included recurrent angina or congestive heart failure that needed admission to hospital, myocardial infarction, repeat revascularization, and cardiac death.

RESULTS

Twenty-six diabetics had retinopathy and 48 diabetics did not have retinopathy. Diabetics with retinopathy were likely to have higher hemoglobin A1c level (p = 0.048), and receive insulin treatment (p = 0.0065). In the 12 months of follow-up, 13 cardiac events occurred in diabetics with retinopathy and 7 in those without retinopathy (p = 0.0021). Among diabetics with retinopathy, heart failure or death due to heart failure accounted for 54% (7 of 13) of these cardiac events. Kaplan-Meier analysis showed significant difference in cardiac event-free survival between the two groups (p < 0.001). After adjustment for differences in patients' characteristics, diabetic retinopathy remained a predictor of cardiac event (adjusted relative risk = 4.2, 95% confidence interval, 1.5% to 11.9%; p = 0.0067).

CONCLUSIONS

After CABG, diabetics with retinopathy have a substantially increased risk of cardiac events, especially of congestive heart failure.

Impaired coronary collateral vessel development in patients with proliferative diabetic retinopathy

BACKGROUND

Diabetic patients have been reported to have impaired coronary collateral vessel growth, although they have excessive neovascularization in the retina.

HYPOTHESIS

This study was designed to compare coronary collateral circulation (CCC) in patients with proliferative diabetic retinopathy (PDR) with that in patients without DR.

METHODS

Ninety diabetic patients with chronic total occlusion in at least one major epicardial coronary artery were enrolled in the study. Groups 1 and 2 consisted of 48 patients without DR and 42 patients with PDR, respectively. Coronary collateral circulation (CCC) was analyzed according to the Rentrop system. Each group was also divided into two subgroups according to poor and good CCC. Serum vascular endothelial growth factor (VEGF) levels were measured using the enzyme-linked immunosorbent assay (ELISA) kit.

RESULTS

The mean Rentrop collateral score was higher in Group 1 than in Group 2 (2.39 +/- 1.07 vs. 1.76 +/- 0.76, respectively, p < 0.001). When the two groups were compared with respect to poor and good CCC, poor CCC was higher in patients with PDR (64 vs. 36%, respectively, p = 0.01). Serum VEGF levels were higher in patients with PDR than in those without DR (219 +/- 99 vs. 139 +/- 98 pg/ml, p < 0.001); however, patients with poor and good CCC had similar VEGF levels.

CONCLUSIONS

We have shown that patients with PDR have a lower coronary collateral score than patients without DR. Also, serum VEGF was significantly higher in patients with PDR than in those without DR. These findings have suggested that diabetes mellitus may have a different action on retinal and coronary circulation.

Early results of off-pump coronary artery bypass grafting for patients on chronic renal dialysis

OBJECTIVE

Renal dialysis is one of the independent risk factors for coronary artery bypass graft surgery. Off-pump coronary artery bypass grafting (OPCAB) may become a good option for these patients. In this study, early results as well as surgical techniques of OPCAB in dialysis patients were analyzed compared with non-dialysis patients.

METHODS

Between July 1997 and December 2002, 471 consecutive patients who underwent OPCAB were enrolled in this study. Among them, 20 patients (4.2%) had received hemodialysis regularly for more than 3 months until the operation. Severity of coronary artery disease or clinical presentations had no significant difference, however, left ventricular function was significantly impaired in dialysis patients.

RESULTS

The average number of anastomosis was 2.8 +/- 1.0 in the dialysis group and 3.2 +/- 1.0 in the non-dialysis group (p=0.056). Twelve patients (60.0%) received 3 or more bypass grafts in the dialysis group. Among them, 6 patients were revascularized only by in-situ or composite arterial conduits using bilateral internal thoracic arteries with or without the gastroepiploic artery. No patients required aortic clamping in the dialysis group. There was no mortality or morbidity in dialysis patients. Perioperaitve bleeding and mechanical ventilation time in the intensive care unit was similar in both groups. No dialysis patients required prolonged mechanical ventilation and hemodialysis from the beginning of the operation to extubation.

CONCLUSION

The rationale for OPCAB for dialysis patients has been established. Total arterial revascularization without aortic clamping is applicable for dialysis patients who require multivessel bypass grafts.

Risk factors for cognitive dysfunction after coronary artery bypass graft surgery in patients with type 2 diabetes

OBJECTIVES

The mechanisms of postoperative cognitive dysfunction in patients with diabetes after coronary artery bypass grafting are not fully understood. We sought to determine which type 2 diabetes-related factors contributed to postoperative cognitive dysfunction at 7 days and 6 months after coronary artery bypass grafting.

METHODS

One hundred eighty patients with type 2 diabetes who were scheduled for elective coronary artery bypass grafting were studied. As a control group, 100 patients without diabetes mellitus matched for age, sex, and educational level were examined. Hemodynamic parameters (arterial and jugular venous blood gas values) were measured during cardiopulmonary bypass. All patients underwent a battery of neurologic and neuropsychologic tests the day before surgery, 7 days after surgery, and 6 months after surgery.

RESULTS

Age (odds ratio 1.5, 95% confidence interval 1.3-1.8, P = .03), presence of hypertension (odds ratio 1.8, 95% confidence interval 1.3-2.0, P = .01), jugular venous oxygen saturation less than 50% time (odds ratio 1.5, 95% confidence interval 1.1-2.0, P = .045), presence of ascending aorta atherosclerosis (odds ratio 1.5, 95% confidence interval 1.1-2.6, P = .01), diabetic retinopathy (odds ratio 2.0, 95% confidence interval 1.3-3.0, P = .01), and insulin therapy (odds ratio 2.0, 95% confidence interval 1.3-3.0, P = .05), were associated with cognitive impairment at 7 days. Insulin therapy (odds ratio 2.0, 95% confidence interval 1.3-3.8, P = .01), diabetic retinopathy (odds ratio 1.3, 95% confidence interval 1.2-2.9, P < .01), and hemoglobin A 1c (odds ratio 1.9, 95% confidence interval 1.3-3.1, P = .047) were associated with cognitive impairment at 6 postoperative months.

CONCLUSIONS

Insulin therapy, diabetic retinopathy, and hemoglobin A 1c were factors in cognitive impairment at 7 days and 6 months after coronary artery bypass grafting in patients with type 2 diabetes.

Diabetic patients have an impaired cerebral vasodilatory response to hypercapnia under propofol anesthesia

BACKGROUND AND PURPOSE

The purpose of this study was to examine the effects of diabetes mellitus and its severity on the cerebral vasodilatory response to hypercapnia.

METHODS

Thirty diabetic patients consecutively scheduled for elective major surgery were studied. After induction of anesthesia, a 2.5-MHz pulsed transcranial Doppler probe was attached to the patient's head at the right temporal window, and mean blood flow velocity of the middle cerebral artery (Vmca) was measured continuously. After the baseline Vmca, arterial blood gases, and cardiovascular hemodynamic values were measured, end-tidal CO2 was increased by reducing ventilatory frequency by 2 to 5 breaths per minute. Measurements were repeated when end-tidal CO2 increased and remained stable for 5 to 10 minutes.

RESULTS

Significant differences were observed in absolute and relative CO2 reactivity between the diabetes and control groups (absolute CO2 reactivity: control, 2.8+/-0.7; diabetes mellitus, 2.1+/-1.3; P<0.01; relative CO2 reactivity: control, 6.3+/-1.4; diabetes mellitus, 4.5+/-2.7; P<0.01, Mann-Whitney U test). Significant differences were also found between diabetic patients with retinopathy and those without retinopathy in absolute (P=0.002) and relative (P=0.002) CO2 reactivity, glycosylated hemoglobin (P=0.0034), and fasting blood sugar (P=0.01) (Scheffé's test, Mann-Whitney U test). There was an inverse correlation between absolute CO2 reactivity and glycosylated hemoglobin (r=0.69, P<0.001).

CONCLUSIONS

Insulin-dependent diabetic patients have an impaired vasodilatory response to hypercapnia compared with that of the control group, and the present findings suggest that their degree of impairment is related to the severity of diabetes mellitus.

Bilateral internal thoracic artery grafting in insulin-treated diabetics: should it be avoided?

BACKGROUND

It has been advocated that skeletonized bilateral internal thoracic artery (BITA) grafting may be implemented safely in diabetics, thus bestowing these patients with the long-term benefits of this strategy. However, the feasibility of this approach in insulin-treated patients has yet to be determined.

METHODS

One-hundred twenty-four insulin-treated diabetics, operated on between April 1996 and December 2001, were compared according to the surgical technique used: BITA (n = 50) or single internal thoracic artery (SITA; n = 74). In the latter, complementary grafts used were saphenous veins and radial arteries.

RESULTS

The groups had comparable risk profiles, with the exception of more neurologic events in the SITA group (21% vs 4%, p = 0.008). There was no significant difference in 30-day mortality (6% vs 4%, p = 0.684), nor in the incidence of neurologic complications (2% vs 8%, p = 0.240). The rate of sternal infection was comparable (4% vs 2.7%, p = 1.000). Use of BITAs was associated with a lower return of angina (4% vs 20%, p = 0.025), less cardiac events (17% vs 38%, p = 0.01), and reduced cardiac mortality (none vs 10%, p = 0.04). Despite the similar 6-year survival (80.5% and 77.4%, p = NS), cardiac-related event-free survival was better in BITA patients (69% vs 23%, p < 0.0001). Multivariate analysis identified use of BITA as a protective factor resulting in less return of angina (p = 0.007) and improved cardiac-related event-free survival (p = 0.001).

CONCLUSIONS

Skeletonized BITA grafting can be performed in insulin-treated diabetics at acceptable risk. This approach may confer improved cardiac outcome. Thus, it should be considered in selected patients.