Subclinical hypothyroidism in combination with vitamin D deficiency increases the risk of impaired left ventricular diastolic function.

OBJECTIVE: Subclinical hypothyroidism and vitamin D deficiency are common. The diastolic function of patients with both subclinical hypothyroidism and vitamin D deficiency remains unknown. This study aimed to investigate diastolic dysfunction in patients with both subclinical hypothyroidism and vitamin D deficiency. SUBJECTS AND METHODS: This study included 254 patients. All patients underwent standard Doppler echocardiography. Patients who had risk factors for diastolic dysfunction or had used L-thyroxine and vitamin D within the previous 3 months were excluded. Vitamin D deficiency was defined as a 25-OH-vitamin D level lower than 20 ng/ml, and vitamin D sufficiency was defined as a 25-OH-vitamin D level ≥ 30 ng/ml. Subclinical hypothyroidism was defined as a TSH level of 4.5-10 mU/l when the free T4 concentration was normal. RESULTS: The patients were divided into 4 groups. Group 1 (n=71) included patients with subclinical hypothyroidism and vitamin D deficiency; Group 2 (n=66) included patients with subclinical hypothyroidism and vitamin D sufficiency; Group 3 (n=65) included euthyroid patients with vitamin D deficiency; and Group 4 (n=52) included euthyroid patients with vitamin D sufficiency. LAVI (31.3 ± 3.2, 28.7 ± 3.0, 28.4 ± 3.4, and 27.9 ± 3.9; p<0.001) and E/E' values (11.2 ± 2.7, 8.9 ± 2.7, 9.1 ± 2.9, 8.8 ± 2.5; p<0.001) were significantly higher in Group 1 than in Groups 2, 3 and 4. E' values were significantly lower in Group 1 than in Groups 2, 3 and 4. CONCLUSION: The coexistence of subclinical hypothyroidism with vitamin D deficiency can lead to further deterioration in the LV diastolic function via the regulation of intracellular calcium and induction of inflammatory activity. Therefore, close follow-up of the diastolic functions of these patients could be beneficial.

Increased serum levels of GDF-15 associated with mortality and subclinical atherosclerosis in patients on maintenance hemodialysis.

BACKGROUND/AIMS: Increased carotid intima-media thickness (CIMT) was shown to be an independent predictor of cardiovascular (CV) mortality in dialysis patients and the general population. Growth differentiation factor 15 (GDF-15), a member of the transforming growth factor superfamily, is produced by cardiomyocytes and atherosclerotic lesions under stress conditions such as inflammation. We assessed associations between serum concentrations of GDF-15, mortality, and CIMT for subclinical atherosclerosis in hemodialysis (HD) patients. METHODS: A total of 87 patients on maintenance hemodialysis and 45 sex- and age-matched healthy controls were included in this prospective study. Serum GDF-15 levels were measured by ELISA. CIMT was assessed by Doppler ultrasonography. The association between serum GDF-15 levels and mortality was assessed using Cox regression analysis with serum levels categorized into two groups according to the median value (328.18 pg/ml). Patients were followed for 2 years and cause-specific and all-cause mortality were determined. RESULTS: The median level of serum GDF-15 was significantly higher in HD patients than controls [328 (198-522) vs. 176 (101-289) pg/ml, p < 0.01, respectively]. Serum GDF-15 levels were correlated to CIMT (r = 0.607, p < 0.001), C-reactive protein (CRP; r = 0.250, p = 0.010), HD duration (r = 0.376, p = 0.004), and serum albumin (r = - 0.156, p = 0.030). The multivariate analysis revealed that GDF-15 was found to be an independent variable of CIMT in HD patients. In the study, the serum GDF-15 level was an independent marker of all-cause of mortality when adjusted for age, CRP, and history of diabetes mellitus. CONCLUSION: The relationship between serum GDF-15, mortality, and carotid artery thickening suggests that GDF-15 may be a novel marker of atherosclerosis, inflammation, and malnutrition in HD patients.

Relationship of galectin-3 to left ventricular geometry and hypertrophy in chronic hemodialysis patients.

AIM AND BACKGROUND: Galectin-3 (Gal-3) is used to determine the prognosis of heart failure. Some studies revealed that Gal-3 promoted cardiac hypertrophy but there is no study in which the relationship between Gal-3 and left ventricular hypertrophy (LVH) geometry in patients without diastolic and systolic function impairment has been explored. The aim of the study was to analyze associations between plasma Gal-3 levels, LVH, and LV geometry in maintenance hemodialysis (HD) patients without systolic and diastolic dysfunction. PATIENTS AND METHODS: The study group included 105 patients (53 women and 52 men)--with an average age of 58.2 ± 12.6 years, treated with HD for an average of 45 ± 32 months--and 60 healthy controls. The Gal-3 and other biochemical parameters were measured and color Doppler echocardiography was performed. For this study LVH was considered present when the LV mass index (LVMI) exceeded 95 g/m(2) in women and 115 g/m(2) in men. Left ventricular geometry was classified into the four groups on the basis of left ventricular mass and relative wall thickness (RWT). RESULTS: Concentric hypertrophy (CH, 40.9 %, n = 43) was the commonest geometric pattern in our study. The Gal-3 levels in CH patients were not different from the patients with eccentric hypertrophy (EH). Plasma levels of Gal-3 correlated with LVMI (r = 0.617, p < 0.001), parathyroid hormone (PTH, r = 0.408, p < 0.001), uric acid (r = 0.281, p = 0.004), C-reactive protein (CRP, r = 0.412, p < 0.001), and RWT (r = 0.281, p = 0.004) but were inversely correlated with albumin (r = - 0.466, P < 0.001) in the whole group. Plasma levels of Gal-3 were associated with LVMI (r = 0.812, P < 0.001), RWT (r = 0.318, p = 0.001), and CRP(r = 0.381, p < 0.001) in maintenance hemodialysis patients. CONCLUSION: The Gal-3 level is related to left ventricular hypertrophy and it is independent of left ventricle geometry. The relationship between LVH and Gal-3 might be direct or it may also be inflammation-related.