Association between chronic low-grade inflammation and metabolic syndrome and their impact on the risk of coronary artery disease in type 1 diabetes

Abstract

Aims: Evaluate the interplay between metabolic syndrome (MS) and chronic low-grade inflammation in type 1 diabetes at different stages of diabetic kidney disease, and to assess whether chronic low-grade inflammation, determined by high-sensitivity C-reactive protein (hs-CRP) increases coronary artery disease risk linked to MS.

Methods: We included 4014 participants with type 1 diabetes from the Finnish Diabetic Nephropathy Study. Hs-CRP was dichotomized by the kidney disease group median for the survival analyses (above median indicated hs-CRP+ and below hs-CRP-). MS-/hs-CRP- was used as the reference category. Follow-up data on coronary artery disease were retrieved from hospital discharge registries and death certificates.

Results: Hs-CRP increased with the number of MS components, irrespective of diabetic kidney disease severity (p < 0.001). In those with normal kidney status, the adjusted HR for coronary artery disease was 1.23 (0.87-1.75) for MS-/hs-CRP+, 1.28 (0.83-1.99) for MS+/hs-CRP-, and 1.53 (1.06-2.21) for MS+/hs-CRP+. In the group with albuminuria and eGFR >60 ml/min/1.73m², neither MS+, hs-CRP+, nor their combinations were associated with increased risk of coronary artery disease. In the group with albuminuria and eGFR <60 ml/min/1.73m², only those with MS+/hs-CRP- had an increased risk of coronary artery disease [adjusted HR 2.00 (1.06-3.77)].

Conclusions: Chronic low-grade inflammation is associated with the MS in type 1 diabetes, irrespective of kidney disease severity. Hs-CRP adds to the coronary artery disease risk associated with the MS only in those without diabetic kidney disease.

Keywords: Coronary artery disease; Diabetic kidney disease; Inflammation; Metabolic syndrome; Risk factors; Type 1 diabetes.