Table 3.
Association of Hours of Sleep, Sleep Quality, and Sleep Disturbance With Risk of Fracture
| Fracture site a | Events n (%) b | Crude (n = 157,306) HR (95% CI) | Multivariable model c (n = 141,079) HR (95% CI) | Multivariable model c (5‐year follow‐up) (n = 141,079) HR (95% CI) |
|---|---|---|---|---|
| Total fracture | 50,601 (2.7) | |||
| How many hours of sleep | ||||
| 5 or less hours | 4,052 (2.8) | 1.11 (1.07–1.15) | 1.10 (1.06–1.14) | 1.12 (1.05–1.20) |
| 6 hours | 13,904 (2.7) | 1.04 (1.02–1.07) | 1.05 (1.02–1.07) | 1.07 (1.03–1.12) |
| 7 hours | 19,306 (2.6) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 8 hours | 11,149 (2.6) | 0.98 (0.96–1.00) | 0.95 (0.93–0.97) | 0.96 (0.91–1.00) |
| 9 hours | 1,975 (2.8) | 1.06 (1.01–1.11) | 0.95 (0.90–0.99) | 0.94 (0.86–1.03) |
| 10 or more hours | 215 (2.5) | 1.01 (0.88–1.16) | 0.96 (0.83–1.11) | 0.99 (0.77–1.26) |
| Overall sleep quality | ||||
| Very restless | 1,145 (2.9) | 1.09 (1.03–1.16) | 0.99 (0.93–1.06) | 1.04 (0.93–1.17) |
| Restless | 7,593 (2.9) | 1.10 (1.07–1.13) | 1.04 (1.01–1.07) | 1.09 (1.04–1.15) |
| Average quality | 21,362 (2.7) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Sound or restful | 14,338 (2.6) | 0.94 (0.92–0.96) | 0.98 (0.96–1.01) | 1.03 (0.99–1.08) |
| Very sound or restful | 6,163 (2.5) | 0.89 (0.87–0.92) | 0.97 (0.94–1.00) | 1.02 (0.96–1.08) |
| Sleep disturbance level | ||||
| 0–3 | 12,922 (2.4) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 4–6 | 13,768 (2.6) | 1.10 (1.07–1.13) | 1.03 (1.01–1.06) | 1.02 (0.97–1.07) |
| 7–10 | 13,386 (2.8) | 1.16 (1.14–1.19) | 1.03 (1.01–1.06) | 0.98 (0.93–1.03) |
| ≥11 | 10,525 (3.0) | 1.26 (1.23–1.29) | 1.08 (1.05–1.11) | 1.03 (0.97–1.08) |
| Insomnia scale | ||||
| No | 34,156 (2.6) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Yes (sleep disturbance ≥9) | 16,445 (2.9) | 1.15 (1.13–1.17) | 1.03 (1.01–1.06) | 1.00 (0.96–1.04) |
| Hip fracture | 5,670 (0.26) | |||
| How many hours of sleep | ||||
| 5 or less hours | 439 (0.26) | 1.08 (0.97–1.19) | 1.01 (0.91–1.14) | 0.82 (0.61–1.09) |
| 6 hours | 1,506 (0.25) | 1.00 (0.94–1.07) | 1.00 (0.93–1.07) | 0.94 (0.79–1.13) |
| 7 hours | 2,177 (0.26) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 8 hours | 1,287 (0.26) | 1.01 (0.94–1.08) | 0.93 (0.87–1.00) | 0.88 (0.72–1.06) |
| 9 hours | 234 (0.28) | 1.12 (0.98–1.28) | 0.93 (0.81–1.07) | 1.07 (0.77–1.50) |
| 10 or more hours | 27 (0.28) | 1.19 (0.81–1.74) | 1.06 (0.71–1.59) | 1.46 (0.69–3.11) |
| Overall sleep quality | ||||
| Very restless | 109 (0.23) | 0.90 (0.74–1.08) | 0.96 (0.78–1.18) | 0.90 (0.52–1.55) |
| Restless | 794 (0.26) | 0.97 (0.90–1.05) | 0.98 (0.90–1.06) | 1.01 (0.81–1.27) |
| Average quality | 2,478 (0.27) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Sound or restful | 1,652 (0.25) | 0.93 (0.88–0.99) | 1.01 (0.94–1.08) | 1.29 (1.08–1.53) |
| Very sound or restful | 637 (0.22) | 0.80 (0.73–0.87) | 0.96 (0.87–1.05) | 1.41 (1.12–1.77) |
| Sleep disturbance level | ||||
| 0–3 | 1,396 (0.23) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 4–6 | 1,502 (0.25) | 1.10 (1.02–1.18) | 0.97 (0.89–1.04) | 0.90 (0.74–1.10) |
| 7–10 | 1,574 (0.28) | 1.25 (1.16–1.34) | 1.00 (0.92–1.08) | 0.88 (0.72–1.07) |
| ≥11 | 1,198 (0.28) | 1.30 (1.20–1.41) | 0.98 (0.90–1.07) | 0.79 (0.63–0.98) |
| Insomnia scale | ||||
| No | 3,777 (0.24) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Yes (sleep disturbance ≥9) | 1,893 (0.28) | 1.19 (1.12–1.25) | 1.00 (0.94–1.06) | 0.87 (0.74–1.02) |
| Upper limb fracture | 19,486 (0.92) | |||
| How many hours of sleep | ||||
| 5 or less hours | 1,580 (0.98) | 1.10 (1.04–1.16) | 1.10 (1.04–1.17) | 1.11 (1.00–1.23) |
| 6 hours | 5,383 (0.94) | 1.04 (1.01–1.08) | 1.05 (1.01–1.09) | 1.06 (0.99–1.14) |
| 7 hours | 7,428 (0.92) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 8 hours | 4,235 (0.89) | 0.97 (0.93–1.01) | 0.94 (0.91–0.98) | 0.95 (0.88–1.03) |
| 9 hours | 780 (0.98) | 1.09 (1.01–1.17) | 1.00 (0.93–1.08) | 0.99 (0.85–1.15) |
| 10 or more hours | 80 (0.86) | 0.98 (0.79–1.22) | 0.97 (0.76–1.22) | 0.93 (0.61–1.41) |
| Overall sleep quality | ||||
| Very restless | 434 (0.98) | 1.05 (0.96–1.16) | 0.97 (0.87–1.08) | 1.00 (0.83–1.22) |
| Restless | 2,912 (1.0) | 1.07 (1.02–1.11) | 1.02 (0.97–1.06) | 1.10 (1.01–1.19) |
| Average quality | 8,294 (0.94) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Sound or restful | 5,469 (0.88) | 0.93 (0.90–0.96) | 0.97 (0.94–1.01) | 1.04 (0.97–1.11) |
| Very sound or restful | 2,377 (0.86) | 0.90 (0.86–0.94) | 0.96 (0.91–1.01) | 0.96 (0.88–1.06) |
| Sleep disturbance level | ||||
| 0–3 | 4,984 (0.84) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 4–6 | 5,280 (0.91) | 1.08 (1.04–1.12) | 1.02 (0.98–1.07) | 1.06 (0.99–1.15) |
| 7–10 | 5,157 (0.95) | 1.14 (1.10–1.18) | 1.03 (0.98–1.07) | 1.00 (0.92–1.08) |
| ≥11 | 4,065 (1.0) | 1.22 (1.17–1.28) | 1.05 (1.01–1.11) | 1.01 (0.93–1.11) |
| Insomnia scale | ||||
| No | 13,096 (0.89) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Yes (sleep disturbance ≥9) | 6,390 (1.0) | 1.15 (1.11–1.18) | 1.03 (1.00–1.07) | 0.97 (0.91–1.03) |
| Lower limb fracture | 19,433 (0.92) | |||
| How many hours of sleep | ||||
| 5 or less hours | 1,632 (1.0) | 1.16 (1.10–1.22) | 1.13 (1.07–1.20) | 1.16 (1.05–1.29) |
| 6 hours | 5,421 (0.95) | 1.06 (1.03–1.10) | 1.06 (1.02–1.10) | 1.10 (1.02–1.17) |
| 7 hours | 7,332 (0.90) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 8 hours | 4,223 (0.89) | 0.98 (0.94–1.02) | 0.96 (0.93–1.00) | 1.00 (0.93–1.07) |
| 9 hours | 737 (0.93) | 1.03 (0.96–1.12) | 0.96 (0.88–1.04) | 0.93 (0.80–1.08) |
| 10 or more hours | 88 (0.95) | 1.09 (0.88–1.35) | 1.01 (0.80–1.26) | 0.88 (0.58–1.33) |
| Overall sleep quality | ||||
| Very restless | 465 (1.1) | 1.16 (1.06–1.28) | 1.01 (0.91–1.12) | 1.04 (0.87–1.25) |
| Restless | 3,032 (1.1) | 1.14 (1.10–1.19) | 1.07 (1.02–1.12) | 1.06 (0.98–1.15) |
| Average quality | 8,086 (0.92) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Sound or restful | 5,474 (0.88) | 0.95 (0.92–0.99) | 1.00 (0.96–1.04) | 1.01 (0.95–1.08) |
| Very sound or restful | 2,376 (0.86) | 0.92 (0.88–0.97) | 0.99 (0.94–1.04) | 1.05 (0.96–1.15) |
| Sleep disturbance level | ||||
| 0–3 | 5,004 (0.85) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 4–6 | 5,202 (0.90) | 1.06 (1.02–1.10) | 1.01 (0.97–1.06) | 1.00 (0.93–1.08) |
| 7–10 | 5,143 (0.96) | 1.13 (1.09–1.18) | 1.03 (0.99–1.08) | 0.99 (0.92–1.07) |
| ≥11 | 4,084 (1.0) | 1.22 (1.18–1.28) | 1.07 (1.02–1.12) | 1.03 (0.94–1.12) |
| Insomnia scale | ||||
| No | 13,105 (0.89) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Yes (sleep disturbance ≥9) | 6,328 (1.00) | 1.13 (1.10–1.17) | 1.04 (1.00–1.07) | 0.99 (0.93–1.05) |
| Central fracture | 15,111 (0.70) | |||
| How many hours of sleep | ||||
| 5 or less hours | 1,234 (0.75) | 1.16 (1.09–1.24) | 1.13 (1.05–1.20) | 0.94 (0.80–1.10) |
| 6 hours | 4,100 (0.70) | 1.05 (1.01–1.09) | 1.05 (1.01–1.10) | 1.02 (0.92–1.13) |
| 7 hours | 5,683 (0.68) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 8 hours | 3,424 (0.70) | 1.03 (0.99–1.08) | 0.97 (0.93–1.02) | 0.92 (0.83–1.03) |
| 9 hours | 601 (0.73) | 1.10 (1.01–1.20) | 0.94 (0.86–1.03) | 0.95 (0.77–1.17) |
| 10 or more hours | 69 (0.72) | 1.15 (0.91–1.46) | 1.08 (0.84–1.38) | 1.04 (0.61–1.77) |
| Overall sleep quality | ||||
| Very restless | 352 (0.78) | 1.11 (0.99–1.23) | 1.10 (0.98–1.24) | 0.94 (0.70–1.25) |
| Restless | 2,289 (0.77) | 1.07 (1.02–1.12) | 1.03 (0.98–1.08) | 1.11 (0.98–1.25) |
| Average quality | 6,510 (0.72) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Sound or restful | 4,246 (0.67) | 0.91 (0.87–0.94) | 0.97 (0.93–1.01) | 1.11 (1.01–1.23) |
| Very sound or restful | 1,714 (0.60) | 0.81 (0.77–0.86) | 0.94 (0.89–1.00) | 1.08 (0.94–1.25) |
| Sleep disturbance level | ||||
| 0–3 | 3,565 (0.59) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| 4–6 | 4,070 (0.68) | 1.17 (1.12–1.23) | 1.05 (1.00–1.10) | 0.99 (0.88–1.11) |
| 7–10 | 4,141 (0.75) | 1.29 (1.24–1.35) | 1.05 (1.00–1.11) | 0.95 (0.84–1.07) |
| ≥11 | 3,335 (0.81) | 1.44 (1.37–1.51) | 1.11 (1.05–1.17) | 0.99 (0.88–1.13) |
| Insomnia scale | ||||
| No | 9,944 (0.65) | 1 (Ref) | 1 (Ref) | 1 (Ref) |
| Yes (sleep disturbance ≥9) | 5,167 (0.79) | 1.24 (1.20–1.28) | 1.05 (1.01–1.09) | 1.00 (0.91–1.09) |
Fractures are through end of extension 2 (September 30, 2015). Note: Missing data for history of fracture after age 55 and parental history of broken hip has been recoded as “unknown” and included in the analysis to preserve sample size.
a
Fracture sites are defined as: Total fracture: any fracture except toes, fingers, coccyx, and sternum; Hip fracture; Upper limb fractures: elbow, hand except fingers, lower arm/wrist, upper arm/humerus or shoulder; Lower limb fractures: foot except toes, knee/patella, upper leg except hip, lower leg/ankle; Central body fractures: hip, pelvis, and spine.
b
% is annualized percent.
c
Multivariable model: age, weight, height, treated diabetes, ethnicity/race, region, smoking status, times fell down last 12 months, general health status, current HT use, oral corticosteroid use, total calcium intake, total vitamin D intake, physical activity, history of fracture after age 55, parental history of broken hip, alcohol intake, depressive symptom score, caffeine intake, HT trial arm and diet modification trial arm, hypnotics medication use, anti‐anxiety medication use, antidepressant medication use, and analgesic narcotic medication use, physical function score and number of chronic conditions (stroke, MI, CHF, diabetes, Parkinson's disease, COPD, asthma, any cancer).