Table 2.
Averaged Objective Sleep Measures and Odds of Dementia or MCI
| Outcome = MCI or Dementia vs. Normal |
||||
|---|---|---|---|---|
| Minimally Adjusteda | Multivariate Adjustedb | |||
| Predictor (average over all nights) | OR (95% CI) | Wald χ2 [1, N=1245], p-value | OR (95% CI) | Wald χ2 [1, N=1223], p-value |
| Total Sleep Time, hours | ||||
| Q1 (<6 hrs, 7 min) | 0.92 (0.69-1.24) | 0.30, p = 0.59 | 0.85 (0.63-1.16) | 1.02, p = 0.31 |
| Q2-3 (6 hrs to <7.5 hrs) | 1.00 (reference) | - - | 1.00 (reference) | - - |
| Q4 (≥7.5 hrs) | 1.00 (0.75-1.33) | 0.00, p = 0.98 | 0.93 (0.69-1.25) | 0.26, p = 0.61 |
| Sleep Efficiency, % | ||||
| Q1 (<74.39) | 1.55 (1.10-2.18) | 6.28, p = 0.01 | 1.53 (1.07-2.19) | 5.34, p = 0.02 |
| Q2 (74.39 to <81.84) | 1.31 (0.93-1.83) | 2.37, p = 0.12 | 1.33 (0.94-1.89) | 2.53, p = 0.11 |
| Q3 (81.84 to <86.26) | 1.34 (0.96-1.88) | 2.91, p = 0.09 | 1.38 (0.97-1.95) | 3.25, p = 0.07 |
| Q4 (≥86.26) | 1.00 (reference) | - - | 1.00 (reference) | - - |
| p-trend | 5.40, p = 0.02 | 4.54, p = 0.03 | ||
| Wake After Sleep Onset, minutes | ||||
| Q1 (<39.25) | 1.00 (reference) | - - | 1.00 (reference) | - - |
| Q2 (39.25 to <58.33) | 1.21 (0.87-1.70) | 1.30, p = 0.26 | 1.27 (0.90-1.80) | 1.87, p = 0.17 |
| Q3 (58.33 to <85.75) | 1.16 (0.83-1.62) | 0.75, p = 0.39 | 1.14 (0.80-1.61) | 0.51, p = 0.47 |
| Q4 (≥85.75) | 1.21 (0.86-1.69) | 1.18, p = 0.28 | 1.16 (0.81-1.66) | 0.66, p = 0.42 |
| p-trend | 0.89, p = 0.35 | 0.33, p = 0.57 | ||
| Sleep Latency, minutes | ||||
| Q1 (<17.25) | 1.00 (reference) | - - | 1.00 (reference) | - - |
| Q2 (17.25 to <28.75) | 1.08 (0.77-1.52) | 0.21, p = 0.65 | 1.12 (0.79-1.59) | 0.41, p = 0.52 |
| Q3 (28.75 to <47.50) | 1.29 (0.92-1.80) | 2.16, p = 0.14 | 1.37 (0.97-1.93) | 3.19, p = 0.07 |
| Q4 (≥47.50) | 1.42 (1.01-1.99) | 4.14, p = 0.04 | 1.37 (0.96-1.94) | 3.04, p = 0.08 |
| p-trend | 5.06, p = 0.03 | 4.07, p = 0.04 | ||
a
Adjusted for age, race, clinic and education
b
Adjusted for age, race, clinic, education, body mass index, number of depressive symptoms, comorbidities, number of IADL impairments, smoking status, alcohol use, exercise, living alone, self-reported health status, antidepressant use, benzodiazepine use, and prescription sleep medication use.
A separate model was run for each predictor.