Table 3.

Associations between insomnia symptom trajectory groups (defined over 13 years) and objective physical function at follow-up visit 13

	40-ft walk, m/s	4-m walk, m/s	Repeated chair stand, s	Grip strength, kg	Balance problem
Insomnia symptom trajectory group	Beta (95% CI)	Beta (95% CI)	Beta (95% CI)	Beta (95% CI)	OR (95% CI)
Model 1
Consistently low	REF	REF	REF	REF	REF
Moderate worsening	−0.02 (−0.06, 0.01)	−0.03 (−0.05, −0.01)	0.46 (0.08, 0.84)	0.11 (−0.57, 0.79)	0.96 (0.58, 1.57)
Improving	−0.03 (−0.07, 0.01)	−0.04 (−0.07, −0.01)*	0.32 (−0.11, 0.76)	−0.27 (−1.04, 0.50)	1.03 (0.60, 1.76)
Severe worsening	−0.03 (−0.07, 0.01)	−0.04 (−0.07, −0.01)*	−0.11 (−0.59, 0.36)	0.68 (−0.17, 1.53)	0.38 (0.17, 0.82)**
Consistently high	0.07 (−0.11, −0.03)**	−0.03 (−0.06, −0.01)	0.62 (0.17, 1.06)*	0.09 (−0.70, 0.89)	1.39 (0.83, 2.33)
Model 2
Consistently low	REF	REF	REF	REF	REF
Moderate worsening	−0.01 (−0.04, 0.03)	−0.02 (−0.05, 0.00)	0.32 (−0.06, 0.71)	0.36 (−0.32, 1.04)	0.92 (0.56, 1.54)
Improving	−0.02 (−0.06, 0.02)	−0.04 (−0.06, −0.01)*	0.21 (−0.23, 0.64)	−0.08 (−0.86, 0.69)	1.01 (0.58, 1.75)
Severe worsening	−0.02 (−0.06, 0.02)	−0.03 (−0.06, 0.00)	−0.29 (−0.77, 0.19)	1.01 (0.15, 1.86)	0.36 (0.16, 0.80)**
Consistently high	−0.05 (−0.09, −0.01)*	−0.02 (−0.05, 0.01)	0.35 (−0.11, 0.81)	0.59 (−0.24, 1.41)	1.35 (0.77, 2.37)

N = 1,237 for 40-ft walk. * p ≤ .05, ** p < .01, *** p < .001. Beta coefficients represent absolute differences (with 95% confidence interval) relative to the referent group. CI: confidence interval; OR: odds ratio; REF: referent group. Model 1 adjusted for race/ethnicity, difficulty paying for basics, marital status, smoking status, education, age, BMI, physical activity, clinical site, and outcome-specific variables. Model 2 adjusted for Model 1 covariates as well as self-rated health status, bodily pain, depressive symptoms, osteoarthritis, osteoporosis, angina/myocardial infarction, stroke, diabetes, cancer, hormone therapy use, menopausal status, and insomnia medication use.