Metabolic syndrome in type 1 diabetes: association with diabetic nephropathy and glycemic control (the FinnDiane study).

OBJECTIVE: The aim of this study was to estimate the prevalence of the metabolic syndrome in Finnish type 1 diabetic patients and to assess whether it is associated with diabetic nephropathy or poor glycemic control. RESEARCH DESIGN AND METHODS: In all, 2,415 type 1 diabetic patients (51% men, mean age 37 years, duration of diabetes 22 years) participating in the nationwide, multicenter Finnish Diabetic Nephropathy (FinnDiane) study were included. Metabolic syndrome was defined according to the National Cholesterol Education Program diagnostic criteria. Patients were classified as having normal albumin excretion rate (AER) (n = 1,261), microalbuminuria (n = 326), macroalbuminuria (n = 383), or end-stage renal disease (ESRD) (n = 164). Glycemic control was classified as good (HbA1c <7.5%), intermediate (7.5-9.0%), or poor (>9.0%). Creatinine clearance was estimated with the Cockcroft-Gault formula. RESULTS: The overall prevalence of metabolic syndrome was 38% in men and 40% in women. The prevalence was 28% in those with normal AER, 44% in microalbuminuric patients, 62% in macroalbuminuric patients, and 68% in patients with ESRD (P < 0.001). Patients with metabolic syndrome had a 3.75-fold odds ratio for diabetic nephropathy (95% CI 2.89-4.85), and all of the separate components of the syndrome were independently associated with diabetic nephropathy. The prevalence of metabolic syndrome was 31% in patients with good glycemic control, 36% in patients with intermediate glycemic control, and 51% in patients with poor glycemic control (P < 0.001). Similarly, metabolic syndrome increased with worsening creatinine clearance. CONCLUSIONS: The metabolic syndrome is a frequent finding in type 1 diabetes and increases with advanced diabetic nephropathy and worse glycemic control.

Low birth weight does not increase the risk of nephropathy in Finnish type 1 diabetic patients.

BACKGROUND: Low birth weight (LBW) has been linked to renal disease both in animal models and human studies. However, the role of birth weight in the development of diabetic nephropathy is unclear. We, therefore, studied the impact of birth weight on the development of diabetic nephropathy and other related traits, such as diabetic retinopathy and macrovascular disease, in Caucasian type 1 diabetic patients. METHODS: Data on size at birth were obtained from original birth certificates in 1543 Finnish patients with type 1 diabetes. The patients were divided into those with low (LBW; below the 10th percentile), normal (NBW; 11-90th percentile) and high birth weight (HBW; above the 90th percentile). RESULTS: Diabetic nephropathy was equally common in the groups with various birth weight (LBW vs NBW vs HBW: 21 vs 20 vs 17%, P = NS). End-stage renal disease (3 vs 5 vs 4%, P = NS), laser-treated retinopathy (31 vs 31 vs 31%, P = NS) and macrovascular disease (5 vs 5 vs 8%, P = NS) were equally prevalent in the various birth weight groups. The time from the onset of diabetes to the onset of diabetic nephropathy was similar irrespective of birth weight (log-rank test; P = NS). CONCLUSIONS: Based on our cross-sectional data, LBW does not have an impact on the development of diabetic nephropathy, laser-treated retinopathy or macrovascular disease later in life in Caucasians with type 1 diabetes.