Table 1.
Characteristics of STURDY accelerometer participants at enrollment by vitamin D3 dose (n=571).
| All (N=571) |
Primary Analysis Population (all doses IU/d; N=571) |
||
|---|---|---|---|
| Pooled Higher Dosesa
(N=293) |
Control (200 IU/d) (N=278) |
||
| Age (years), mean (SD) | 77.2 (5.3) | 77.2 (5.3) | 77.2 (5.3) |
| Sex, no. (%) | |||
| Male | 322 (56.4) | 163 (55.6) | 159 (57.2) |
| Female | 249 (43.6) | 130 (44.4) | 119 (42.8) |
| Race, no. (%)b | |||
| White | 457/566 (80.7) | 229/291 (78.7) | 228/275 (82.9) |
| Black | 93/566 (16.4) | 50/291 (17.2) | 43/275 (15.6) |
| Other | 19/566 (3.4) | 13/291 (4.5) | 6/275 (2.2) |
| BMI (kg/m2), mean (SD) | 30.6 (6.1) (570/571) | 30.6 (5.8) (292/293) | 30.6 (6.4) |
| Chronic conditions, no. (%) | |||
| Cardiovascular disease/PAD | 178 (31.2) | 87 (29.7) | 91 (32.7) |
| Hypertension | 366 (64.1) | 197 (67.2) | 169 (60.8) |
| Stroke | 35 (6.1) | 15 (5.1) | 20 (7.2) |
| Lung disease | 48 (8.4) | 27 (9.2) | 21 (7.6) |
| Diabetes | 150 (26.3) | 87 (29.7) | 63 (22.7) |
| Kidney disease | 17 (3.0) | 8 (2.7) | 9 (3.2) |
| Liver disease | 36 (6.3) | 22 (7.5) | 14 (5.0) |
| Arthritis | 312 (54.6) | 161 (55.0) | 151 (54.3) |
| Parkinson’s disease | 8 (1.4) | 4 (1.4) | 4 (1.4) |
| Multiple sclerosis | 2 (0.4) | 0 | 2 (0.7) |
| Number of comorbidities, Mean (SD) | 2.0 (1.2) | 2.1 (1.2) | 2.0 (1.2) |
| Serum vitamin D (ng/mL)c | |||
| 10 to 19 ng/mL, no. (%) | 168 (29.4) | 83 (28.3) | 85 (30.6) |
| 20 to 29 ng/mL, no. (%) | 403 (70.6) | 210 (71.7) | 193 (69.4) |
| Mean (SD) | 22.0 (5.1) | 22.0 (4.9) | 22.0 (5.2) |
| Taking a personal vitamin D supplement, no. (%) | 214 (37.5) | 112 (38.2) | 102 (36.7) |
| Fell ≥1 time in prior year, no. (%) | 366 (64.1) | 191 (65.2) | 175 (63.0) |
| SPPBd total score | |||
| Mean (SD) | 8.8 (2.4) | 8.7 (2.4) | 8.9 (2.4) |
| Physical Activity Variables, Mean (SD) | |||
| TACe | 1,911,732 (573,548) | 1,821,141 (552,249) | 1,883,496 (609,331) |
| Active time/d (min)e | 388.26 (109.55) | 373.93 (110.05) | 380.32 (117.48) |
| ASTP (%)e | 26.09 (6.89) | 26.34 (7.13) | 26.56 (7.66) |
Abbreviations: IU/d = international units per day; SD = standard deviation; IQR = interquartile range; SPPB = Short Physical Performance Battery; BMI = body mass index.
Note: The burn-in cohort (participants randomized before any adjustments were made to randomization probabilities) was randomized between October 2015 and August 2, 2018.
Pooled Higher Doses denotes the combined 1000, 2000, and 4000IU/d groups.
Race was self-reported from a list of 5 categories (American Indian or Alaska Native, Asian, Black or African American, Native Hawaiian or other Pacific Islander, White); more than one race could be reported by a participant.
The range of serum vitamin D level eligible for STURDY (10–29 ng/mL) includes levels termed deficient (<20 ng/mL) or insufficient (20–29 ng/mL) by the Endocrine Society and overlaps with levels termed deficient (<12 ng/mL), inadequate (12–19ng/mL), or adequate (>=20) by the Institute of Medicine.
The Short Physical Performance Battery (SPPB) is a 3-part assessment of physical functioning: balance testing, 4-meter walk, and demonstration of ability to complete 5 chair stands (stand up from a seated position in a chair); each part is scored 0 to 4 and the total SPPB score (range 0 to 12) is the sum of the 3 subscores. Higher scores indicate better physical function.
TAC = Total Activity Counts; ASTP = Activity fragmentation defined by the active-to-sedentary transition probability; Active time/d = minutes per day spent at or above an activity threshold of 1853 counts/min.