Investigation of early signs of systolic and diastolic dysfunction among persons with type 1 diabetes.

Background: Persons with type 1 diabetes have a higher risk to develop heart failure than the general population, and the mechanism behind the increased risk is unclear. In epidemiological studies with hospitalisation for heart failure as endpoint HbA1c, body mass index and decreased kidney function are significant risk factors, but it is unclear how these risk factors influence the development of heart failure. Methods: In this study, we investigated early signs of systolic and diastolic dysfunction with transthoracic echocardiography. Statistical analysis on correlation of risk factors and early signs of diastolic and systolic dysfunction was made. Results: In this study population of 287 persons with type 1 diabetes, 160 were men and 127 were women with a mean age of 53.8 (SD 11.6) years and a mean diabetes duration of 36.2 (SD 13.5) years. There were 23 (8.2%) persons who fulfilled the definition of systolic dysfunction (ejection fraction <50% or regional wall motion abnormalities) and 24 persons (9%) the definition for diastolic dysfunction. When comparing the groups with either systolic or diastolic dysfunction to the rest of the population, the only significant risk factor was age in both groups and previous myocardial infarction in the systolic group. Conclusion: In our study population with type 1 diabetes, we found signs of diastolic dysfunction in 9% and systolic dysfunction in 8.2%. Compared with published data from the general population, this rate is somewhat higher in a younger population. Only age was a significant risk factor in the study.

Body mass index as a risk factor for coronary events and mortality in patients with type 1 diabetes.

Objective: To investigate the potential relationship between body mass index (BMI) and the risk for myocardial infarction and coronary death in patients with type 1 diabetes. Methods: We studied patients with type 1 diabetes included in the Swedish National Diabetes Registry during 2002-2004 and followed them until a discharge diagnosis for myocardial infarction, acute coronary event, death or until 31 December 2011. Cox regression was used to estimate relative risks. Results: In 17 499 patients with type 1 diabetes (mean age 39.4 years; mean BMI 25.2 kg/m2), 819 were diagnosed with myocardial infarction as a primary or secondary diagnosis during a mean follow-up of 8.5 years (maximum 9.9 years). Estimated with Cox regression, there was no significant effect of increased BMI on the risk of myocardial infarction (HR 1.4 (95% CI 0.7 to 2.5) in the group with BMI >35 kg/m2 compared with BMI 18.5-25 kg/m2. There was no association between BMI and coronary mortality, acute coronary events or all-cause mortality after adjusting for other known risk factors. Underweight patients (BMI <18.5 kg/m2) had increased hazard for coronary (HR 5.0 (95% CI 1.5 to 16.9)) and all-cause mortality (HR 5.4 (95% CI 3.1 to 9.6)) compared with BMI 18.5-25 kg/m2. Conclusions: Among patients with type 1 diabetes, increased BMI is not a significant independent risk factor for myocardial infarction or coronary death after adjustment for other risk factors. Low BMI (less than 18.5 kg/m2) is associated with mortality from coronary or any cause.

Long-term excess risk of heart failure in people with type 1 diabetes: a prospective case-control study.

BACKGROUND: Diabetes is an established risk factor for heart failure, but because nearly all heart failure occurs in older individuals, the excess risk and risk factors for heart failure in individuals with type 1 diabetes are not known. We aimed to determine the excess risk of heart failure in individuals with type 1 diabetes overall and by different levels of glycaemic control and albuminuria. METHODS: In this prospective case-control study, we identified all individuals with type 1 diabetes registered in the Swedish National Diabetes Registry between Jan 1, 1998, and Dec 31, 2011, and five controls randomly selected from the general population for each patient, matched according to age, sex, and county, and compared them with respect to subsequent hospital admissions for heart failure, with hazard ratios calculated with Cox regression. FINDINGS: In a cohort of 33 402 patients (mean age at baseline 35 years [SD 14], 15 058 [45%] women, and mean duration of diabetes 20·1 years [SD 14·5]), over a mean follow-up of 7·9 years, 1062 (3%) patients were admitted to hospital with a diagnosis of heart failure, compared with 1325 (1%) of 166 228 matched controls over 8·3 years, giving a HR 4·69 (95% CI 3·64-6·04), after adjustment for time-updated age, sex, time-updated diabetes duration, birth in Sweden, educational level, and baseline comorbidities. Worse glycaemic control was associated with increased risk of heart failure in a graded fashion, and so was the presence of albuminuria. Risk of heart failure was also increased among those with well controlled diabetes (adjusted HR 2·16 [95% CI 1·55-3·01]) and in those with no albuminuria (3·38 [2·51-4·57]), but not in the subgroup both well-controlled and with normoalbuminuria (1·59 [0·70-3·58]). INTERPRETATION: Individuals with type 1 diabetes had a four-times increase in the risk of being admitted to hospital with heart failure compared with population-based controls. Poor glycaemic control and impaired renal function substantially increased the risk of heart failure. FUNDING: The Swedish state, Swedish Society for Physicians, the Health & Medical Care Committee of the Regional Executive Board (Region Vastra Gotaland, Sweden), the Swedish Heart-Lung Foundation, Diabetes Wellness, Novo Nordisk Foundation (PI M Lind), the Swedish Research Council, and the Swedish Council for working life and social research (Epilife).

Decreased eGFR as a Risk Factor for Heart Failure in 13 781 Individuals With Type 1 Diabetes.

BACKGROUND: Impaired renal function is a well-known risk factor of cardiovascular disease, but its relation to heart failure in individuals with type 1 diabetes has been sparsely studied. The aim of our study was to quantify the risk increase for development of heart failure with decreasing kidney function in individuals with type 1 diabetes. METHODS: Three equations were used to calculate eGFR (estimated glomerular filtration rate) for individuals with T1D and no known heart failure in the Swedish National Diabetes Registry. Proportional hazards regression models were constructed to evaluate the association between eGFR and hospitalization for heart failure (HF). RESULTS: Among 13 781 individuals (mean age 41.1 [SD 13.3] years at baseline), 330 (2.4%) were hospitalized for HF over median follow-up of 7.0 years. Renal function was normal (eGFR > 90 mL/min/1.73 m(2)) in 67% of individuals according to the Cockcroft-Gault formula, compared to 51% and 41% according to the Chronic Kidney Disease Epidemiology (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) formulas. For eGFR 45-60 ml/min/1.73 m(2), hazard ratios (HRs) for hospitalization (reference >90 mL/min/1.73 m(2)) were 3.18 (95% CI 2.17, 4.65), 2.12 (1.16, 3.08), and 2.44 (1.69, 3.55) using the Cockcroft-Gault, MDRD, and CKD-EPI formulas. With eGFR <30 ml/min/1.73 m(2) there was a HR of 3.78 (2.15, 5.91), 3.44 (2.14, 5.51), and 3.51 (2.21, 5.51) compared to normal kidney function (>90 mL/min/1.73 m(2)). CONCLUSIONS: In individuals with T1D, risk of hospitalization for heart failure was over 2 times greater at eGFR 45-60 ml/min/1.73 m(2) and more than 3 times greater at eGFR <30 ml/min/1.73 m(2) when compared to normal eGFR.

Relationship between overweight and obesity with hospitalization for heart failure in 20,985 patients with type 1 diabetes: a population-based study from the Swedish National Diabetes Registry.

OBJECTIVE: To investigate the potential relationship between overweight, obesity, and severe obesity and the risk of hospitalization for heart failure (HF) in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: We studied patients with type 1 diabetes included in the Swedish National Diabetes Registry during 1998-2003, and they were followed up until hospitalization for HF, death, or 31 December 2009. Cox regression was used to estimate relative risks. RESULTS: In a sample of 20,985 type 1 diabetic patients (mean age, 38.6 years; mean BMI, 25.0 kg/m(2)), 635 patients were hospitalized with HF as a primary or secondary diagnosis during a median follow-up of 9.1 years. Cox regression adjusting for age, sex, diabetes duration, smoking, HbA1c, systolic and diastolic blood pressures, and baseline and intercurrent comorbidities (including myocardial infarction) showed a significant relationship between BMI and hospitalization for HF (P < 0.0001). In reference to patients in the BMI 20-25 kg/m(2) category, hazard ratios (HRs) were as follows: HR 1.22 (95% CI, 0.83-1.78) for BMI <20 kg/m(2); HR 0.94 (95% CI, 0.78-1.12) for BMI 25-30 kg/m(2); HR 1.55 (95% CI, 1.20-1.99) for BMI 30-35 kg/m(2); and HR 2.90 (95% CI, 1.92-4.37) for BMI ≥ 35 kg/m(2). CONCLUSIONS: Obesity, particularly severe obesity, is strongly associated with hospitalization for HF in patients with type 1 diabetes, whereas no similar relation was present in overweight and low body weight.

The relationship between glycaemic variability and cardiovascular complications in patients with acute myocardial infarction and type 2 diabetes: a report from the DIGAMI 2 trial.

AIMS: Hyperglycaemia during hospitalization for acute myocardial infarction (AMI) is a risk predictor, but attempts to improve the prognosis by insulin-based glucose control have not been consistently successful. Increased glycaemic variability, a potential effect of insulin treatment, has been linked to a worse prognosis in critically ill patients. The present aim was to study the possibility of such a relation in patients with type 2 diabetes (T2DM) and AMI. METHOD AND RESULTS: We studied 578 T2DM patients who had glucose levels measured hourly while receiving an insulin-glucose infusion during the first 48 h of hospitalization for AMI. Three measures of glycaemic variability: root mean square error (RMSE), range, and slope were studied in relation to a composite endpoint of mortality, stroke, and reinfarction and to mortality. In unadjusted analyses, the mean level of glycaemic variability did not differ between patients who died during 12 months of follow-up compared with those who survived. In a Cox regression model adjusting for age and previous congestive heart failure, there was no increased risk for the composite endpoint associated with increased glycaemic variability; RMSE: hazard ratio (HR) 1.09 [95% confidence interval (CI) 0.93-1.27; P = 0.28], range: HR 1.01 (95% CI: 0.98-1.05; P = 0.47), and slope: HR 1.01 (95% CI: 0.99-1.04; P = 0.40). There was furthermore no increased risk in mortality; RMSE HR 1.14 (95% CI: 0.93-1.38; P = 0.21), range HR 1.03 (95% CI: 0.98-1.08; P = 0.28), and slope HR 1.01 (95% CI: 0.98-1.04; P = 0.55). CONCLUSION: The 1-year risk for death, reinfarction, or stroke did not relate to glycaemic variability in T2DM patients with AMI treated with insulin infusion.