Table 1: Characteristics of the study sample ( unless otherwise noted).

VariableMean or %SD

Age (years)57.54.4
Race (% Caucasian)84.5%
Body mass index (kg/m2)24.44.7
Household income (% ≥75 K/year)a67.2%
Perceived stress (PSS score)b23.26.0
Time in bed (hours)c8.01.0
Sleep duration (hours)d7.21.0
Sleep onset latency (minutes)17.218.9
Sleep quality (1 = very bad, 5 = very good)3.80.8
Telomere Length (T/S converted to base pairs)5547.0330.7

a , b , c , d .