High-sensitivity cardiac troponin T and cognitive function and dementia risk: the atherosclerosis risk in communities study

Abstract

Aim: Clinical cardiovascular disease is a major risk factor for cognitive impairment and dementia. However, less is known about the association of subclinical myocardial damage with cognition and dementia. We sought to examine the associations of high-sensitivity cardiac troponin T (hs-cTnT) with cognition and dementia.

Methods and results: Cross-sectional analysis of cognition (baseline 1996-98) and prospective analysis of dementia (follow-up through 2010) in 9472 participants in the Atherosclerosis Risk in Communities study. High-sensitivity cardiac troponin T was measured using a novel highly sensitive assay with a lower limit of the blank of 3 ng/L. Cognitive function was assessed by three tests: the delayed word recall test (DWRT), the digit symbol substitution test (DSST), and the word fluency test (WFT). Dementia was defined using ICD-9 codes. Linear regression and Cox models were adjusted for traditional cardiovascular risk factors. The mean age of participants was 63 years, 59% were female, 21% were black, and 66% had hs-cTnT ≥3 ng/L. In cross-sectional analyses, higher hs-cTnT was associated with lower scores on the DSST (P-trend < 0.001) and the WFT (P-trend = 0.002), but not on the DWRT (P-trend = 0.089). Over a median of 13 years, there were 455 incident dementia hospitalizations. In prospective analyses, higher baseline concentrations of hs-cTnT were associated with an increased risk for dementia hospitalizations overall (P-trend < 0.001) and for vascular dementia (P-trend = 0.029), but not for Alzheimer's dementia (P-trend = 0.212).

Conclusion: Elevations in baseline concentrations of hs-cTnT were associated with lower cognitive test scores at baseline and increased dementia hospitalization risk during the follow-up. Our results suggest that subclinical myocardial injury is associated with cognition and dementia.

Keywords: Cognition; Dementia; High-sensitivity Troponin T.

Figure 1

Adjusted restricted cubic spline model showing the hazard ratios (95% confidence intervals) for the association of high-sensitivity cardiac troponin T with incident dementia [among the 6321 participants with high-sensitivity cardiac troponin T concentrations within the measuring range (≥3 ng/L)]. Knots at 4, 6, and 14 ng/L (10th, 50th, and 90th percentiles). Histogram shows the distribution of concentrations of high-sensitivity cardiac troponin T within the measuring range. Data truncated at 97.5 percentile of high-sensitivity cardiac troponin T. Model is adjusted for age (continuous), race/field centre (Washington County, Maryland whites; suburbs of Minneapolis, Minnesota whites; Forsyth County, North Carolina whites; Forsyth County, North Carolina blacks; Jackson, Mississippi blacks), sex (male; female), education level (