TNNT2 and insomnia: In unadjusted analyses, higher circulating cTnT concentration was associated with insomnia symptoms without regard to other sleep characteristics β 0.12 (standard error [SE] 0.03, p < .01); insomnia symptoms with actigraphy-defined short sleep duration β 0.24 (SE 0.04, p < .01); and insomnia with actigraphy-defined fragmented sleep β 0.27 (SE 0.03, p < .01).