Hyperglycemia, assessed according to HbA1c, and future risk of venous thromboembolism: the Tromsø study

Abstract

NorwayTo cite this article: Lerstad G, Brodin EE, Enga KF, Jorde R, Schirmer H, Njølstad I, Svartberg J, Braekkan SK, Hansen J-B. Hyperglycemia, assessed according to HbA 1c , and future risk of venous thromboembolism: the Tromsø study. J Thromb Haemost 2014; 12: 313-9.Summary. Background: HbA 1c , a marker of average plasma glucose level during the previous 8-12 weeks, is associated with the future risk of cardiovascular disease and all-cause mortality. Objectives: To examine the association between hyperglycemia, assessed according to HbA 1c , and the future risk of venous thromboembolism (VTE) in a population-based cohort. Methods: HbA 1c was measured in 16 156 unique subjects (25-87 years) who participated in one or more surveys of the Tromsø study (Tromsø 4, 1994(Tromsø 4, -1995 Tromsø 5, 2001 Tromsø 5, -2002 and Tromsø 6, 2007-2008). All subjects were followed, and incident VTE events were recorded up to 31 December 2010. Results: There were 333 validated first VTE events, of which 137 were unprovoked, during a median followup of 7.1 years. HbA 1c was not associated with the future risk of VTE in analyses treating HbA 1c as a continuous variable, or in categorized analyses. The risk of VTE increased by 5% per one standard deviation (0.7%) increase in HbA 1c (multivariable-adjusted hazard ratio [HR] 1.05; 95% confidence interval [CI] 0.97-1.14), and subjects with HbA 1c ≥ 6.5% had a 27% higher risk than those with HbA 1c < 5.7% (multivariable-adjusted HR 1.27; 95% CI 0.72-2.26). There was no significant linear trend for an increased risk of VTE across categories of HbA 1c (P = 0.27). Conclusions: Serum levels of HbA1c were not associated with the future risk of VTE in multivariable analysis. Our findings suggest that hyperglycemia does not play an important role in the pathogenesis of VTE.

Glucose levels and diabetes are not associated with the risk of venous thrombosis: results from the MEGA case‐control study

“…Previous case‐control studies provided evidence that hyperglycaemia was associated with the risk of VT, but in nearly all these studies blood was drawn at the time of the thrombotic event, where stress‐induced hyperglycaemia either by the thrombotic event (Hermanides et al, ; Tichelaar et al, ) or surgery (Cohn et al, ) could have occurred, leading to spurious results. In two large cohort studies, no association was found between HbA1c and the incidence of subsequent VT (Bell et al , ; Lerstad et al , ), where reverse causation could not have occurred. While a limited number of cases were identified during follow‐up ( n = 345 VT cases out of 12 298 participants and n = 333 VT cases out of 16,156 participants, respectively), these findings are consistent with our observations in the current analysis.…”

Hepatitis C Virus Infection Associated With an Increased Risk of Deep Vein Thrombosis

“…However, plasma levels of glycohemoglobin were not consistently associated with increased risk of VTE in 2 studies. 29 , 30 The possible explanation is that the increased prothrombotic status in diabetics is mainly due to the chronic inflammation, and insulin resistance 31 rather than simply hyperglycemia. Our study did not support an association between DM and increased risk of DVT.…”

Diabetic aggravation of stroke and animal models

“…Immediately after stable embolus or thrombus formation causes the occlusion of cerebral blood vessels, the supply of oxygen and glucose to some parts of the brain is reduced below a critical level which, if continued for a protracted period, results in a progressive loss of brain function seen during stroke (Roger et al, 2012). A heightened level of thromboembolism is noted in diabetic subjects having relatively less control over their hyperglycemia (Eyadiel et al, 2014; Lerstad et al, 2014; Tala et al, 2014). Naïve (non-diabetic) subjects suffering from acute ischemic attack are successfully treated with anticoagulant and/or anti-platelet drugs (Abdul-Rahim et al, 2015).…”