P M Nilsson

Smoking is associated with increased HbA1c values and microalbuminuria in patients with diabetes — data from the National Diabetes Register in Sweden

OBJECTIVES The aim was to examine trends in the proportion of smoking in diabetes patients, and to study associations between smoking, glycaemic control, and microalbuminuria. METHODS Smoking habits were reported to the Swedish National Diabetes Register (NDR), with data from hospitals and primary health care. Patient characteristics included were age, gender, type of treatment, diabetes duration, HbA1c, BMI, blood pressure, antihypertensive and lipid-lowering drugs, and microalbuminuria. RESULTS The proportion of smokers in type 1 diabetes was 12-15% during 1996-2001, it was high in females<30 years (12-16%), and was higher in the age group 30-59 years (13-17%) than in older (6-9%) patients. The corresponding proportion of smoking in type 2 diabetes was 10-12%, higher in those less than 60 years of age (17-22%) than in older (7-9%) patients. Smoking type 1 and type 2 patients in 2001 had higher mean HbA1c but lower mean BMI values than non-smokers. Smokers also had higher frequencies of microalbuminuria, in both type 1 (18 vs 14%) and type 2 (20% vs 13%) diabetes. Multiple logistic regression analyses disclosed that smoking was independently associated with elevated HbA1c levels (p<0.001) and microalbuminuria (p<0.001), but negatively with BMI (p<0.001), in both type 1 and type 2 diabetes. CONCLUSIONS Smoking in patients with diabetes was widespread, especially in young female type 1, and in middle-aged type 1 and type 2 diabetes patients, and should be the target for smoking cessation campaigns. Smoking was associated with both poor glycaemic control and microalbuminuria, independently of other study characteristics.

Low levels of insulin-like growth-factor-binding protein-1 (IGFBP-1) are prospectively associated with the incidence of type 2 diabetes and impaired glucose tolerance (IGT): the Söderåkra Cardiovascular Risk Factor Study.

AIM To explore the association between baseline levels of insulin-like growth-factor-binding protein-1 (IGFBP-1), a marker of insulin sensitivity, and the development of type 2 diabetes or impaired glucose tolerance (IGT) in a specifically defined middle-aged population. METHODS This cross-sectional population-based screening study was conducted in 1989-1990 and included baseline data for 664 non-diabetic subjects aged 40-59 years. Clinical data were collected and blood samples analyzed for blood glucose, serum lipids and insulin. Blood specimens were frozen at baseline and later analyzed for IGF-I, IGFBP-1 and C-reactive protein (CRP). At the follow-up in 2006, the incidence of type 2 diabetes and IGT was reported based on primary-care medical records. RESULTS During the 17-year observation period, 42 subjects (6.3%) developed type 2 diabetes/IGT. Those in the lowest quintile of IGFBP-1 (< or =24 microg/L) at baseline had a diabetes incidence of 12.6% while, in the highest quintile of IGFBP-1 (> or =59 microg/L), the incidence was 1.5%. Coxs proportional-hazards model regression analyses were used to determine the incidence of type 2 diabetes/IGT, corrected for age and gender, in relation to IGFBP-1, CRP and waist circumference. Subjects in the lowest IGFBP-1 quintile showed an independently increased risk of type 2 diabetes/IGT [hazards ratio (HR): 3.54; 95% CI 1.18-10.6; P=0.024]. For CRP and waist circumference, the corresponding figures were HR: 6.81; 95% CI 2.50-18.6; P<0.001 and HR: 3.33; 95% CI 1.47-7.6; P=0.004, respectively. CONCLUSION Low levels of IGFBP-1 predicted the long-term development of type 2 diabetes or IGT in a middle-aged population. The association was independent of CRP and abdominal obesity.

Pulse pressure strongly predicts cardiovascular disease risk in patients with type 2 diabetes from the Swedish National Diabetes Register (NDR).

OBJECTIVES To analyze pulse pressure (PP) as a risk predictor for coronary heart disease (CHD), stroke and cardiovascular disease (CVD; CHD and/or stroke) in type 2 diabetic patients. METHODS A total of 11,128 female and male type 2 diabetic patients with known baseline PP values and no CVD, aged 50-74 years, were followed for a mean duration of 5.6 years (1998-2003). A subgroup of 5521 patients with known mean PP values (mean values at baseline and at the end of the study) was also included. RESULTS Hazard ratios (HRs) with 95% CI for fatal/nonfatal CHD with baseline or mean PP>or=75mmHg, compared to <75mmHg, were 1.23 (1.07-1.40; P=0.003) and 1.32 (1.07-1.62; P=0.009), respectively, after adjusting for mean blood pressure (MBP), age, gender, diabetes duration, HbA(1c), body mass index (BMI), lipid-reducing drugs, microalbuminuria > 20microg/min, antihypertensive drugs and hypoglycaemic treatment, using Cox regression analyses. Fully-adjusted respective HRs for stroke were 1.17 (0.98-1.39) and 1.21 (0.90-1.61) and, for CVD, 1.23 (1.10-1.37; P<0.001) and 1.28 (1.07-1.52; P=0.007). Fully-adjusted HRs for baseline PP increased per quartile and, CHD, stroke or CVD, were 1.09 (1.03-1.16; P=0.004), 1.14 (1.05-1.23; P=0.002) and 1.11 (1.05-1.17; P<0.001), respectively. The data suggest that, if a mean PP>or=75mmHg were to be avoided, then 15% and 17% of CHD and or CVD, cases, respectively, in such a cohort might be prevented after multivariable adjustments, with a further 10% of cases avoided if also adjusted for MBP and age. Increasing baseline MBP, age and microalbuminuria were independently and significantly associated (P<0.001) with increasing baseline or mean PP. CONCLUSION Increased PP is a powerful independent risk predictor of CVD in type 2 diabetic patients, and lowering PP can lead to a marked reduction in risk.

Total adiponectin does not predict cardiovascular events in middle-aged men in a prospective, long-term follow-up study.

AIM Plasma total adiponectin is a marker of insulin resistance, but its role in predicting cardiovascular events is unclear. We aimed to investigate the role of adiponectin as a predictor of cardiovascular risk in middle-aged men, and to describe the association between adiponectin and glucose metabolism. METHODS In this population-based prospective study of middle-aged men (n=3885), total adiponectin was analyzed. All individuals had undergone an oral glucose tolerance test (OGTTs), and the mean follow-up duration was 27 years. Regression analyses were carried out for indices of glucose metabolism in relation to quintiles (Q1-Q5) of total adiponectin levels. After stratification for smoking or not, the association between total adiponectin and the first incidence of fatal or non-fatal cardiovascular disease (CVD) was analyzed, using Coxs proportional-hazards regression model. RESULTS In a separate multiple-regression analysis and after adjusting for possible confounders, the relationship between adiponectin levels and markers of glucose metabolism were found to be significant (P<0.05). However, adiponectin did not independently predict the risk of stroke, coronary events, or a combination of these two outcomes. CONCLUSION Levels of total plasma adiponectin are not useful for predicting long-term cardiovascular events in middle-aged men, but are strongly associated with glucose metabolism and markers of insulin resistance.