Glycaemic control not a risk factor for cerebral small vessel disease in T1D

Among patients with type 1 diabetes (T1D), medium- and long-term blood glucose control and long-term glycaemic variability do not exert any influence on the risk of developing cerebral small vessel disease (cSVD), a study has found.

The study included 189 patients (median age 40.0 years, 47.1 percent men) with T1D (median duration 21.7 years). Researchers collected glycated haemoglobin (HbA_1c) values over the course of 10 years. They also performed other assessments including a clinical examination, biochemical sampling, and brain magnetic resonance imaging.

The mean systolic blood pressure of the population was 130 mm Hg. Of the patients, 66 (34.9 percent) exhibited signs of cSVD, 45 (23.8 percent) had cerebral microbleeds (CMBs), 32 (16.9 percent) had white matter hyperintensities (WMHs), and four (2.1 percent) had lacunar infarcts. The overlap between these changes was 11 (5.8 percent) for CMBs and WMHs and two (1.1 percent) for both CMBs or WMHs and lacunar infarct.

Fifty-five (29.1 percent) patients were on insulin pump treatment. The median HbA_1c, glycated albumin, and fructosamine values throughout the visits were 8.1 percent (65.0 mmol/mol), 91.6 nM/ml, and 2.6 mM/l, respectively. HbA_1c-mean_overall, collected over the course of 10 years, was 8.1 percent.

Neither medium-/long-term glucose control nor glycaemic variability differed in individuals with vs without signs of cSVD. Furthermore, there was no between-group difference detected in any of the blood glucose variables and cSVD stratified for CMBs or WMHs.

The numbers of CMBs also showed no association with the studied glucose variables. Additionally, after dividing the studied variables into quartiles, no association with cSVD was seen.

The findings came as a surprise to the researchers, given the large number of signs of cerebrovascular pathology in T1D patients after two decades of chronic hyperglycaemia. More studies are needed to assess the underlying factors of cSVD.