Table 1.
Participants Characteristics and Sleep Health Traits in Delirium and Nondelirium Groups
| New-Onset Delirium Participants (n = 4 775) | Nondelirium Participants (n = 321 818) | ||
|---|---|---|---|
| Mean (SD), or % | Mean (SD), or % | p | |
| Demographics | |||
| Age at baseline | 64.0 (5.4) | 57.8 (7.9) | <.001 |
| Male | 57.3% | 45.7% | <.001 |
| College attendance | 20.7% | 30.0% | <.001 |
| Ethnic background (European) | 95.5% | 94.2% | .078 |
| Townsend deprivation index* | −0.62 (3.4) | −1.25 (3.1) | <.001 |
| BMI/lifestyle | |||
| Body mass index (kg/m2) | 28.7 (5.5) | 27.7 (4.9) | <.001 |
| Physical activity (MET-min)† | 2586 (2835) | 2651 (2752) | .036 |
| Alcohol (≥4 drinks/week) | 47.5% | 46.5% | .15 |
| Cardiovascular risk/comorbidities/cognition | |||
| CVD risk score‡ | 1.24 (1.1) | 0.70 (0.9) | <.001 |
| Dementia/Parkinson’s disease | 2.5% | 0.2% | <.001 |
| Respiratory disease | 14.2% | 14.0% | .59 |
| Liver/GI disease | 9.1% | 8.9% | .66 |
| Renal disease | 1.6% | 1.5% | .84 |
| Cancer diagnosed | 12.1% | 8.8% | <.001 |
| Vitamin D (deficient)§ | 17.2% | 13.3% | <.001 |
| Hypnotic/sedative use | 5.3% | 1.5% | <.001 |
| Cognition (reaction time)‖ | 613 (145) | 563 (119) | <.001 |
| Sleep traits and disorders | |||
| Sleep disorders¶ | 1.5% | 0.9% | <.001 |
| Sleep duration (h/day) | <.001 | ||
| Short (<6) | 8.1% | 6.1% | |
| Normal (6–9) | 87.4% | 92.7% | |
| Long (>9) | 4.4% | 2.1% | |
| Excessive daytime sleepiness | <.001 | ||
| Never/rarely | 64.1% | 74.5% | |
| Sometimes | 30.0% | 22.3% | |
| Often/all the time | 5.8% | 3.1% | |
| Insomnia-like complaints | <.001 | ||
| Never/rarely | 21.8% | 22.5% | |
| Sometimes | 43.8% | 47.3% | |
| Usually | 34.4% | 30.2% | |
| Napping | <.001 | ||
| Never/rarely | 41.2% | 54.3% | |
| Sometimes | 47.6% | 39.9% | |
| Usually | 11.2% | 5.8% | |
| Chronotype | .02 | ||
| Early/intermediate | 91.5% | 92.1% | |
| Late | 8.5% | 7.9% | |
| Poor sleep behavior burden | <.001 | ||
| Minimal (0–1) | 27.7% | 37.8% | |
| Mild (2, 3) | 46.5% | 46.2% | |
| Moderate (4, 5) | 20.1% | 13.5% | |
| Severe (≥6) | 5.8% | 2.5% |
Notes: SD = standard deviation; CVD = cardiovascular disease; MET = metabolic equivalent; BMI = body mass index; GI = gastrointestinal. UK Biobank participant characteristics at baseline expressed as mean (SD) for continuous variables or number (percentage) for categorical variables. Participants were compared based on delirium status (new-onset delirium vs delirium-free participants). Categorical data presented as a percentage of participants present. p values from one-way analysis of variance tests for continuous measures and Pearson’s chi-squared tests for categorical data.
*Higher value indicated worse deprivation.
†METS-min/week increase.
‡CVD risk score: summed hypertension, cholesterol, diabetes mellitus, smoking status, and ischemic heart disease.
§Vitamin D levels: sufficient >50 nmol/L, low 25–50 nmol/L, and deficient <25 nmol/L.
‖Cognition reaction time in milliseconds: average timed tests of symbol matching.
¶Sleep disorders: any from sleep apnea, insomnia, and other disorders such as hypersomnia, sleep-wake disorders, and narcolepsy-catalepsy.