Katarina Eeg-Olofsson

Effectiveness and safety of metformin in 51 675 patients with type 2 diabetes and different levels of renal function: a cohort study from the Swedish National Diabetes Register

Objective To evaluate the effectiveness and safety of metformin use in clinical practice in a large sample of pharmacologically treated patients with type 2 diabetes and different levels of renal function. Design Observational study between July 2004 and December 2010, mean follow-up 3.9 years. Setting Hospital outpatient clinics and primary care in Sweden. Participants 51 675 men and women with type 2 diabetes, registered in the Swedish National Diabetes Register, and on continuous glucose-lowering treatment with oral hypoglycaemic agents (OHAs) or insulin. Main outcome measures Risks of cardiovascular disease (CVD), all-cause mortality and acidosis/serious infection, associated with each treatment regimens, were analysed in all patients and in subgroups with different estimated glomerular filtration rate (eGFR) intervals. Covariance adjustment and propensity scores were used to adjust for several baseline risk factors and characteristics at Cox regression. Results Compared with metformin in monotherapy, HRs for fatal/non-fatal CVD and all-cause mortality with all other OHAs combined (approximately 80% sulphonylureas) in monotherapy were 1.02 (95% CI 0.93 to 1.12) and 1.13 (1.01 to 1.27), while 1.18 (1.07 to 1.29) and 1.34 (1.19 to 1.50) with insulin in monotherapy, adjusting using propensity scores. Metformin, compared with any other treatment, showed reduced risks of acidosis/serious infection (adjusted HR 0.85, 95% CI 0.74 to 0.97) and all-cause mortality (HR 0.87, 95% CI 0.77 to 0.99), in patients with eGFR 45–60 ml/min/1.73 m2, and no increased risks of all-cause mortality, acidosis/serious infection or CVD were found in patients with eGFR 30–45 ml/min/1.73 m2. Conclusions Metformin showed lower risk than insulin for CVD and all-cause mortality and slightly lower risk for all-cause mortality compared with other OHA, in these 51 675 patients followed for 4 years. Patients with renal impairment showed no increased risk of CVD, all-cause mortality or acidosis/serious infection. In clinical practice, the benefits of metformin use clearly outbalance the risk of severe side effects.

New aspects of HbA1c as a risk factor for cardiovascular diseases in type 2 diabetes: an observational study from the Swedish National Diabetes Register (NDR).

Abstract.  Eeg‐Olofsson K, Cederholm J, Nilsson PM, Zethelius B, Svensson A‐M, Gudbjörnsdóttir S, Eliasson B (Institute of Medicine, Sahlgrenska University Hospital, University of Gothenburg, Gothenburg; Department of Public Health and Caring Sciences/Family Medicine and Clinical Epidemiology, Uppsala University, Uppsala; Department of Clinical Sciences, Lund University, University Hospital, Malmö; Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala; and Center of Registers in Region Västra Götaland, Gothenburg, Sweden) New aspects of HbA1c as a risk factor for cardiovascular diseases in type 2 diabetes: an observational study from the Swedish National Diabetes Register (NDR). J Intern Med 2010; 268: 471–482.

Risk Prediction of Cardiovascular Disease in Type 2 Diabetes: A risk equation from the Swedish National Diabetes Register

OBJECTIVE—Risk prediction models obtained in samples from the general population do not perform well in type 2 diabetic patients. Recently, 5-year risk estimates were proposed as being more accurate than 10-year risk estimates. This study presents a diabetes-specific equation for estimation of the absolute 5-year risk of first incident fatal/nonfatal cardiovascular disease (CVD) in type 2 diabetic patients with use of A1C and clinical characteristics. RESEARCH DESIGN AND METHODS—The study was based on 11,646 female and male patients, aged 18–70 years, from the Swedish National Diabetes Register with 1,482 first incident CVD events based on 58,342 person-years with mean follow-up of 5.64 years. RESULTS—This risk equation incorporates A1C, as in the UK Prospective Diabetes Study risk engine, and several clinical characteristics: onset age of diabetes, diabetes duration, sex, BMI, smoking, systolic blood pressure, and antihypertensive and lipid-reducing drugs. All predictors included were associated with the outcome (P < 0.0001, except for BMI P = 0.0016) with Cox regression analysis. Calibration was excellent when assessed by comparing observed and predicted risk. Discrimination was sufficient, with a receiver operator curve statistic of 0.70. Mean 5-year risk of CVD in all patients was 12.0 ± 7.5%, whereas 54% of the patients had a 5-year risk ≥10%. CONCLUSIONS—This more simplified risk equation enables 5-year risk prediction of CVD based on easily available nonlaboratory predictors in clinical practice and A1C and was elaborated in a large observational study obtained from the normal patient population aged up to 70 years.

Glycaemic control of Type 1 diabetes in clinical practice early in the 21st century: an international comparison

Improving glycaemic control in people with Type 1 diabetes is known to reduce complications. Our aim was to compare glycaemic control among people with Type 1 diabetes using data gathered in regional or national registries.

Glycemic control and cardiovascular disease in 7,454 patients with type 1 diabetes : an observational study from the Swedish National Diabetes Register (NDR).

OBJECTIVE We assessed the association between A1C and cardiovascular diseases (CVDs) in an observational study of patients with type 1 diabetes followed for 5 years. RESEARCH DESIGN AND METHODS A total of 7,454 patients were studied from the Swedish National Diabetes Register (aged 20–65 years, diabetes duration 1–35 years, followed from 2002 to 2007). RESULTS Hazard ratios (HRs) for fatal/nonfatal coronary heart disease (CHD) per 1% unit increase in baseline or updated mean A1C at Cox regression analysis were 1.31 and 1.34 and 1.26 and 1.32, respectively, for fatal/nonfatal CVD (all P < 0.001 after adjustment for age, sex, diabetes duration, blood pressure, total and LDL cholesterol, triglycerides, BMI, smoking, and history of CVD). HRs were only slightly lower for CHD (P = 0.002) and CVD (P = 0.002–0.007) after also adjusting for albuminuria. Adjusted 5-year event rates of CHD and CVD increased progressively with higher A1C, ranging from 5 to 12%, as well as when subgrouped by shorter (1–20 years) or longer (21–35 years) duration of diabetes. A group of 4,186 patients with A1C 5–7.9% (mean 7.2) at baseline showed risk reductions of 41% (95% confidence intervals: 15–60) (P = 0.005) for fatal/nonfatal CHD and 37% (12–55) (P = 0.008) for CVD, compared with 3,268 patients with A1C 8–11.9% (mean 9.0), fully adjusted also for albuminuria. CONCLUSIONS This observational study of patients in modern everyday clinical practice demonstrates progressively increasing risks for CHD and CVD with higher A1C, independently of traditional risk factors, with no J-shaped risk curves. A baseline mean A1C of 7.2% showed considerably reduced risks of CHD and CVD compared with A1C 9.0%, emphasizing A1C as a strong independent risk factor in type 1 diabetes.

Glycemic control and cardiovascular disease in 7454 patients with type 1 diabetes: an observational study from the Swedish National Diabetes Register (NDR)

OBJECTIVE We assessed the association between A1C and cardiovascular diseases (CVDs) in an observational study of patients with type 1 diabetes followed for 5 years. RESEARCH DESIGN AND METHODS A total of 7,454 patients were studied from the Swedish National Diabetes Register (aged 20–65 years, diabetes duration 1–35 years, followed from 2002 to 2007). RESULTS Hazard ratios (HRs) for fatal/nonfatal coronary heart disease (CHD) per 1% unit increase in baseline or updated mean A1C at Cox regression analysis were 1.31 and 1.34 and 1.26 and 1.32, respectively, for fatal/nonfatal CVD (all P < 0.001 after adjustment for age, sex, diabetes duration, blood pressure, total and LDL cholesterol, triglycerides, BMI, smoking, and history of CVD). HRs were only slightly lower for CHD (P = 0.002) and CVD (P = 0.002–0.007) after also adjusting for albuminuria. Adjusted 5-year event rates of CHD and CVD increased progressively with higher A1C, ranging from 5 to 12%, as well as when subgrouped by shorter (1–20 years) or longer (21–35 years) duration of diabetes. A group of 4,186 patients with A1C 5–7.9% (mean 7.2) at baseline showed risk reductions of 41% (95% confidence intervals: 15–60) (P = 0.005) for fatal/nonfatal CHD and 37% (12–55) (P = 0.008) for CVD, compared with 3,268 patients with A1C 8–11.9% (mean 9.0), fully adjusted also for albuminuria. CONCLUSIONS This observational study of patients in modern everyday clinical practice demonstrates progressively increasing risks for CHD and CVD with higher A1C, independently of traditional risk factors, with no J-shaped risk curves. A baseline mean A1C of 7.2% showed considerably reduced risks of CHD and CVD compared with A1C 9.0%, emphasizing A1C as a strong independent risk factor in type 1 diabetes.

Insulin pump therapy, multiple daily injections, and cardiovascular mortality in 18 168 people with type 1 diabetes: observational study

Objective To investigate the long term effects of continuous subcutaneous insulin infusion (insulin pump therapy) on cardiovascular diseases and mortality in people with type 1 diabetes. Design Observational study. Setting Swedish National Diabetes Register, Sweden 2005-12. Participants 18 168 people with type 1 diabetes, 2441 using insulin pump therapy and 15 727 using multiple daily insulin injections. Main outcome measures Cox regression analysis was used to estimate hazard ratios for the outcomes, with stratification of propensity scores including clinical characteristics, risk factors for cardiovascular disease, treatments, and previous diseases. Results Follow-up was for a mean of 6.8 years until December 2012, with 114 135 person years. With multiple daily injections as reference, the adjusted hazard ratios for insulin pump treatment were significantly lower: 0.55 (95% confidence interval 0.36 to 0.83) for fatal coronary heart disease, 0.58 (0.40 to 0.85) for fatal cardiovascular disease (coronary heart disease or stroke), and 0.73 (0.58 to 0.92) for all cause mortality. Hazard ratios were lower, but not significantly so, for fatal or non-fatal coronary heart disease and fatal or non-fatal cardiovascular disease. Unadjusted absolute differences were 3.0 events of fatal coronary heart disease per 1000 person years; corresponding figures were 3.3 for fatal cardiovascular disease and 5.7 for all cause mortality. When lower body mass index and previous cardiovascular diseases were excluded, results of subgroup analyses were similar to the results from complete data. A sensitivity analysis of unmeasured confounders in all individuals showed that an unmeasured confounders with hazard ratio of 1.3 would have to be present in >80% of the individuals treated with multiple daily injections versus not presence in those treated with pump therapy to invalidate the significantly lower hazard ratios for fatal cardiovascular disease. Data on patient education and frequency of blood glucose monitoring were missing, which might have influenced the observed association. Conclusion Among people with type 1 diabetes use of insulin pump therapy is associated with lower cardiovascular mortality than treatment with multiple daily insulin injections.

Glycemic and Risk Factor Control in Type 1 Diabetes: Results from 13,612 patients in a national diabetes register

OBJECTIVE—This study was designed to investigate the clinical characteristics of a large type 1 diabetic population and to evaluate the degree of fulfillment of recently updated treatment goals. RESEARCH DESIGN AND METHODS—The Swedish National Diabetes Register was initiated in 1996 as a tool for quality assurance in diabetes care. A1C levels, treatment, and risk factors were analyzed in two cross-sectional samples of 9,424 patients in 1997 and 13,612 patients in 2004 and in a smaller longitudinal sample from 1997 to 2004. RESULTS—Mean A1C decreased from 8.2 ± 1.3% in 1997 to 8.0 ± 1.2% in 2004 (P < 0.001). The proportion of patients reaching A1C <7.0% increased from 17.4 to 21.2% in 2004. A slow but significant improvement in blood pressure levels was seen, but only 61.3% reached the blood pressure goal of <130/80 mmHg in 2004. Lipid control improved, and the use of lipid-lowering drugs increased. Among patients treated with lipid-lowering agents, 38% reached the goal of total cholesterol <4.5 mmol/l, and 48% reached the goal of LDL cholesterol <2.5 mmol/l. Successful long-term glycemic and blood pressure control were both independently predicted by low BMI and the absence of microalbuminuria in 1997. CONCLUSIONS—In this large cohort of type 1 diabetic patients, there was a slow improvement in glycemic and risk factor control from 1997 to 2004, although the gap between the clinical results and current Swedish and American treatment goals is still unsatisfactory. It is crucial that additional measures be taken to improve risk factor control in type 1 diabetic patients.

Blood pressure and risk of cardiovascular diseases in type 2 diabetes: further findings from the Swedish National Diabetes Register (NDR-BP II).

Objectives: Estimate risks of coronary heart disease (CHD), stroke and cardiovascular disease (CVD) with updated mean systolic (SBP) and diastolic (DBP) blood pressure in an observational study of patients with type 2 diabetes. Methods: Thirty-five thousand and forty-one patients treated with antihypertensive drugs, and 18 512 untreated patients, aged 30–75 years, without previous heart failure, followed for 6 years until 2009. Results: In treated patients, nonlinear splines for 6-year risk of fatal/nonfatal CHD, stroke and CVD by BP as a continuous variable showed a progressive increase with higher SBP from 140 mmHg and higher, and with DBP from 80 mmHg, with a J-shaped risk curve at lowest SBP levels, but not obviously at lowest DBP levels. Analysing intervals of SBP with 130–134 mmHg as reference at Cox regression, adjusted hazard ratios (HR) for fatal/nonfatal CHD, stroke and CVD with at least 140 mmHg were 1.22 [95% confidence interval (CI): 1.08–1.39], 1.43 (1.18–1.72), 1.26 (1.13–1.41), all P < 0.001. HR with 115–129 and 135–139 mmHg were nonsignificant, whereas increased with 100–114 mmHg, 1.96 (P < 0.001), 1.75 (P = 0.02), 2.08 (P < 0.001), respectively. With DBP 75–79 mmHg as reference, adjusted HR for fatal/nonfatal CHD, stroke and CVD with DBP 80–84 mmHg were 1.42 (1.26–1.59), 1.46 (1.24–1.72), 1.39 (1.26–1.53), all P < 0.001. Corresponding HR with DBP at least 85 mmHg were 1.70 (1.50–1.92), 2.35 (1.99–2.77), 1.87 (1.69–2.07), all P < 0.001. Corresponding HR with DBP 60–69 and 70–74 mmHg were nonsignificant. The picture was similar in 7059 patients with previous CVD and in untreated patients. Conclusion: BP around 130–135/75–79 mmHg showed lower risks of cardiovascular diseases in patients with type 2 diabetes.

A new model for 5-year risk of cardiovascular disease in type 2 diabetes, from the Swedish National Diabetes Register (NDR).

AIM We assessed the association between risk factors and cardiovascular disease (CVD) in an observational study of type 2 diabetes patients from the Swedish National Diabetes Register. METHODS A derivation sample of 24,288 patients, aged 30-74 years, 15.3% with previous CVD, baseline 2002, 2488 CVD events when followed for 5 years until 2007. A separate validation data set of 4906 patients, baseline 2003, 522 CVD events when followed for 4 years. RESULTS Adjusted hazard ratios at Cox regression for fatal/nonfatal CVD were: onset-age 1.59, diabetes duration 1.55, total-cholesterol-to-HDL-cholesterol ratio 1.20, HbA1c 1.12, systolic BP 1.09, BMI 1.07 (1 SD increase in natural log continuous variables); males 1.41, smoker 1.35, microalbuminuria 1.27, macroalbuminuria 1.53, atrial fibrillation 1.50, previous CVD 1.98 (all p<0.001 except BMI p=0.0018). All 12 variables were used to elaborate an equation for 5-year CVD risk in the derivation dataset: mean 5-year risk 11.9±8.4%. Calibration in the validation dataset was adequate: ratio predicted 4-year risk/observed rate 0.97. Discrimination was sufficient: C statistic 0.72, sensitivity 51% and specificity 78% for top quartile. CONCLUSION This CVD risk model from a large observational study of patients in routine care showed adequate calibration and discrimination, and can be useful for clinical practice.