Table 2: Sleep disturbances and risk of cognitive impairment or dementia -longitudinal studies.
Study |
Exposure |
Outcome |
Follow up (years) |
Results |
Blackwell [31] |
Sleep disturbance (actigraphy) |
CI (TMT-Trails B) |
3.5 |
SE < 70 vs. ≥ 70: adj OR 1.53 (95%CI 1.07 to 2.18) WASO < 90 vs. ≥ 90: adj OR 1.47 (95%CI 1.09 to 1.98) No. of long wake episodes < 8 vs. ≥ 8. adj OR: 1.38 (95%CI 1.02 to 1.86) |
Sleep disturbance (ESS) |
≤ 10 vs. 10: adj OR 1.27 (95%CI 0.87 to1.87) |
|||
Sleep disturbance (PSQI) |
≤ 5 vs. > 5 adj OR: 1.16 (95%CI 0.86, 1.55) |
|||
Sleep disturbance (actigraphy) |
CI (3MS) |
SE < 70 vs. ≥ 70: adj OR 1.17 (95%CI 0.88, 1.54) WASO < 90 vs. ≥ 90: adj OR 1.15 (95%CI 0.92, 1.45) No. of long wake episodes < 8 vs. ≥ 8. adj OR: 1.36 (95%CI 1.09, 1.71) |
||
Sleep disturbance (ESS) |
≤ 10 vs. 10: adj OR 0.97 (95%CI 0.71, 1.34) |
|||
Sleep disturbance (PSQI) |
≤ 5 vs. > 5: adj OR: 0.89 (95%CI 0.71, 1.11) |
|||
Bokenberger [32] |
Sleep disturbance (KSQ) |
Dementia (ICD-10) |
up to 17 |
Time in bed ≤ 6 h: adj HR 1.40 (95%CI 1.06–1.85) > 9 h adj HR 1.11 (95%CI 1.00–1.24) compared with middle reference group Rise time 8 AM or later adj HR 1.12 (95%CI 1.01-1.24) Sleep quality index adj HR 0.93 (95%CI 0.85-1.01) Restorative sleep index adj HR 0.94 (95%CI 0.80-1.09) |
Chen [34] |
Insomnia (ICD-9-CM) |
Dementia (ICD-9-CM) |
3 |
adj HR 2.34 (95%CI 1.92-2.85)
|
Diem [35] |
Sleep disturbance (Actigraphy) |
Mild CI or dementia |
2 |
SE < 74% vs. SE > 86%: adj OR 1.53 (95% CI 1.07, 2.19; |
Elwood [36] |
Insomnia (WSQ) |
Vascular dementia or CI |
10 |
Insomnia: adJ OR: 2.32 (95%CI 1.05 to 5.11) Daytime sleepiness: adj OR: 3.15 (95%CI 1.76 to 5.63) |
Non-vascular dementia or CI |
Insomnia: adJ OR: 1.02 (95%CI 0.54 to 1.94) Daytime sleepiness: adj OR: 1.35 (95%CI 0.88 to 2.07) |
|||
Hoile [43] |
Insomnia (red code on primary care dataset) |
Dementia (red code on primary care dataset) |
5-10 |
Adj OR 1.34 (95% CI 1.20 to 1.50) |
Hung [37] |
Insomnia (ICD-9-CM) |
Dementia (ICD 9-CM) |
3 |
Adj HR: 2.14 (95%CI 2.01 to 2.29) |
Lin [38] |
SRMD (ICD-9-CM) |
Dementia, Alzheimer disease (ICD 9-CM) |
5 |
Adj HR: 3.952 (95%CI 1.124 to 2.767) |
Potvin [39] |
Sleep disturbance (PSQI) |
CI (MMSE) |
1 |
Women: adj OR: 1.02 (95%CI 0.96-1.10) Men: adj OR 1.17 (95%CI 1.05-1.30) |
Yaffe [42] |
Any sleep disturbance, insomnia (ICD 9-CM) |
dementia (ICD 9-CM) |
8 |
any sleep disturbance: adj HR: 1.27, 95% CI: 1.20, 1.34 insomnia: adj HR: 1.29, 95% CI:1.20, 1.39 |
CI: Cognitive Impairment; SE: Sleep Efficiency; WASO: Wake After Sleep Onset; 3MS: Modified Mini-Mental State Examination; MMSE: Mini-Mental State Examination; KSQ Karolinska Sleep Questionnaire; WSQ: Wisconsin Sleep Questionnaire. SRMD: Sleep-Related Movement Disorders; PSQI: Pittsburgh Sleep Quality Index; In bold statistically significant results