Table 2.
Sleep Measures by Thyroid Hormone Status
| Mean (95% CI) by Thyroid Hormone Status | ||||
|---|---|---|---|---|
| Sleep Measure | Subclinical Hyperthyroidism (TSH<0.55 mIU/L) (n = 15) |
Euthyroidism (TSH 0.55–4.78 mIU/L) (n = 629) |
Subclinical Hypothyroidism (TSH>4.78 mIU/L) (n = 38) |
P value for trend |
| Objective Measures | ||||
| Nightly sleep duration, hours | ||||
| Unadjusted | 6.0 (5.4, 6.6) | 6.4 (6.3, 6.5) | 6.4 (6.0, 6.8) | 0.46 |
| Age+clinic-adjusted | 5.9 (5.3, 6.5) | 6.4 (6.3, 6.5) | 6.4 (6.0, 6.8) | 0.43 |
| Multivariate-adjusted* | 6.0 (5.4, 6.6) | 6.4 (6.3, 6.5) | 6.4 (6.0, 6.8) | 0.37 |
| Sleep efficiency, % | ||||
| Unadjusted | 73.8 (67.8, 79.7) | 78.2 (77.2, 79.1) | 79.5 (75.8, 83.3) | 0.16 |
| Age+clinic-adjusted | 73.2 (67.3, 79.1) | 78.1 (77.2, 79.1) | 79.9 (76.2, 83.7) | 0.09 |
| Multivariate-adjusted* | 73.6 (67.8, 79.3) | 78.1 (77.2, 79.0) | 80.4 (76.8, 84.1) | 0.06 |
| Wake after sleep onset, min | ||||
| Unadjusted | 91.8 (69.7, 113.9) | 78.2 (74.8, 81.6) | 69.1 (55.3, 83.0) | 0.08 |
| Age+clinic-adjusted | 93.2 (71.3, 115.0) | 78.3 (74.9, 81.7) | 67.1 (53.3, 80.9) | 0.04 |
| Multivariate-adjusted* | 91.9 (70.7, 113.2) | 78.4 (75.2, 81.7) | 65.5 (52.1, 78.8) | 0.02 |
| Sleep latency, min | ||||
| Unadjusted | 28.4 (19.0, 42.5) | 22.3 (21.0, 23.7) | 20.7 (16.1, 26.7) | 0.26 |
| Age+clinic-adjusted | 29.5 (19.8, 44.1) | 22.3 (21.0, 23.7) | 20.7 (16.0, 26.6) | 0.21 |
| Multivariate-adjusted* | 29.3 (19.6, 43.8) | 22.3 (21.0, 23.7) | 20.6 (16.0, 26.6) | 0.22 |
| Long wake episodes, number | ||||
| Unadjusted | 7.8 (6.2, 9.4) | 6.9 (6.7, 7.2) | 6.3 (5.3, 7.3) | 0.13 |
| Age+clinic-adjusted | 7.9 (6.3, 9.5) | 6.9 (6.7, 7.2) | 6.2 (5.2, 7.2) | 0.07 |
| Multivariate-adjusted* | 7.8 (6.3, 9.4) | 6.9 (6.7, 7.2) | 6.2 (5.2, 7.2) | 0.07 |
| Subjective Measures | ||||
| Nightly sleep duration, hours | ||||
| Unadjusted | 6.1 (5.5, 6.7) | 6.9 (6.8, 6.9) | 6.9 (6.5, 7.2) | 0.18 |
| Age+clinic-adjusted | 6.1 (5.5, 6.7) | 6.9 (6.8, 7.0) | 6.9 (6.5, 7.3) | 0.15 |
| Multivariate-adjusted* | 6.1 (5.5, 6.7) | 6.9 (6.8, 6.9) | 6.9 (6.5, 7.3) | 0.11 |
| PSQI score (range 0–21) | ||||
| Unadjusted | 6.9 (5.3, 8.6) | 5.6 (5.4, 5.9) | 6.0 (5.0, 7.1) | 0.80 |
| Age+clinic-adjusted | 7.0 (5.3, 8.6) | 5.6 (5.4, 5.9) | 5.9 (4.9, 6.9) | 0.63 |
| Multivariate-adjusted* | 7.0 (5.4, 8.6) | 5.7 (5.4, 5.9) | 5.7 (4.7, 6.7) | 0.38 |
| Epworth score (range 0–24) | ||||
| Unadjusted | 5.9 (4.0, 7.8) | 6.1 (5.8, 6.4) | 6.1 (4.9, 7.3) | 0.97 |
| Age+clinic-adjusted | 6.0 (4.1, 7.9) | 6.1 (5.8, 6.4) | 6.1 (4.9, 7.3) | 0.99 |
| Multivariate-adjusted* | 5.9 (4.0, 7.8) | 6.1 (5.9, 6.4) | 6.0 (4.8, 7.2) | 0.90 |
*
Adjusted for age, clinic, race, education, lives alone, IADL impairment, history of diabetes, history of CHF, history of COPD, 3MS score, and BMI.
3MS = Teng Modified Mini-Mental State Examination; BMI = Body Mass Index; CHF = Congestive Heart Failure; CI = Confidence Interval; COPD = Chronic Obstructive Pulmonary Disease; IADL = Instrumental Activities of Daily Living; PSQI = Pittsburgh Sleep Quality Index; TSH = Thyroid Stimulating Hormone.