Clinical and metabolic characteristics of treated hyperlipidemic patients additionally affected by subclinical hyperglycemia

BACKGROUND: Impaired glucose regulation (IGR) and hyperlipidemia (HL) are associated with an increased risk of developing a cardiovascular disease. Hyperlipidemic patients were shown to bear a greater risk for an increased intima media thickness (IMT). However little is known about differences between treated hyperlipidemic patients (HL) with normal (NGR) or impaired (IGR) glucose regulation. METHODS: We performed a cross-sectional study, involving 96 non-diabetic HL patients with IGR (fasting plasma glucose of ≥ 100 mg/dl and <126 mg/dl or/and HbA1c-level of ≥ 5.7 and <6.5 %) or with NGR (HbA1c-level of <5.7 % and a fasting glucose <100 mg/dl). We compared metabolic characteristics and the IMT between the two groups. Insulin sensitivity in fasting conditions was described by HOMA-IR and QUICKI. RESULTS: HL-IGR patients were older (57.6 ± 10.4 vs. 49.1 ± 8.7, p < 0.001), had higher carotid IMT measurements (IMT average: 0.68 ± 0.14 vs. 0.60 ± 0.09, p = 0.002; IMT right: 0.67 ± 0.15 vs. 0.60 ± 0.10, p = 0.013; IMT left: 0.63 vs. 0.57, p = 0.009), as well as a higher chance to exceed a cut-off value of ≥0.8 mm or insignificant stenosis within this investigation (OR: 3.9, 95 % CI: 1.15-13.22, p = 0.029) compared to HL-NGR-patients. Furthermore HL-IGR patients were characterised by a higher waist circumference (100.6 ± 10.1 vs. 91.6 ± 13.3, p < 0.001), higher fasting plasma glucose-levels (100.1 ± 10.8 vs. 88.1 ± 6.6, p < 0.001), higher HbA1c concentrations (5.8 ± 0.33 vs. 5.3 ± 0.24, p < 0.001) and C-peptide levels (2.70 vs. 2.10, p = 0.012). Age and CVD status were in general the only two variables which independently explained IMT. CONCLUSION: Our study showed that among patients with treated hyperlipidemia the presence of IGR characterised subjects who were older and had a significantly higher risk for an increased IMT compared with those maintaining NGR. Further studies are necessary to evaluate if this specific subpopulation with IGR can benefit from a more strict multifactorial management and perhaps from an additional early antihyperglycaemic treatment.