Cerebrovascular disorders in diabetic patients with resistant hypertension and factors associated with their severity

Abstract

Abstract Introduction Diabetes mellitus (DM) and hypertension (HTN) are associated with accelerated brain damage that often precedes the development of stroke and dementia. However, little is known about the features of silent brain damages and possible mechanisms of their development in patients with resistant hypertension (RHTN) and type 2 DM. Objective To study the features of MRI- sings of silent brain damage in patients RHTN with type 2 DM and to establish the factors associated with their development. Methods We studied 46 with RHTN and type 2 DM (mean age 60.3±7.9 years; 27 females (59%), mean 24-hour (systolic/diastolic) BP 169.0±16.4/89.0±14.7 mmHg, HbA1c 7.4±1.3%). On average, patients were taking 4.3±1.0 antihypertensive drugs. Patients were subjected to brain MRI (1.5 T), 24-hour BP monitoring, lab tests (HbA1c, TNF-α, hsCRP, leptin, resistin, aldosterone, basal end postprandial serum glucose, insulin, C-peptide). According to MRI linear dimensions of liquor spaces (subarachnoidal spaces (SAS), lateral ventricles, III and IV ventricles), white matter lesions (WMLs), basal ganglia and thalamus abnormalities were assessed. In addition, severity of periventricular WMLs (PWMLs) was evaluated semi-quantitatively on a scale of 0 to 4. Results The frequency of ventricular dilatation was 45%, expansion of SAS – 65%, lacunar infarctions – 25%, focal WMLs (diameter <3 mm) – 52%, PWMLs – 89%. According to the correlation analysis, an increase in density of the MR signal of PWMLs was associated with an increase in levels of TNF-α (r=0.55 p=0.01) and hsCRP (r=0.64 p=0.045). The increase in density of the MR signal from basal ganglia and thalamus correlated with postprandial levels of glucose (r=0,48 p=0,025; r=0.46 p=0.04, respectively), insulin (r=0.54 p=0.011; r=0.52 p=0.017, respectively) and C-peptide (r=0.54 p=0.011; r=0.46 p=0.037, respectively), as well as with basal level of insulin (r=0.52 p=0.007; r=0.48 p=0.012, respectively) and the leptin (r=0.40 p=0.027; r=0.36 p=0.048, respectively). The severity of PWMLs depended on the level of basal glycaemia (r=0.35, p=0.020) and HbA1c (r=0.37, p=0.04). The transverse size of the chiasmal cistern had a relationship with of the resistin level (r=0.43, p=0.03), and the transverse size of the III ventricle correlated with the serum aldosterone level (r=0.51, p=0.13). There were no direct correlations between MRI- sings of silent brain damage and blood pressure levels. Conclusion Thus, diabetic patients with resistant hypertension have a high frequency of white matter lesions and of liquorodynamics dysturbanses. The severity of these changes depends on a complex of metabolic, pro-inflammatory and neurohormonal factors in the absence of a direct relationship with the blood pressure level. Funding Acknowledgement Type of funding sources: None.