Table 1.
Characteristics of study participants by osteoarthritis (OA) status, NHANES 1988–94 and 1999–2010
| Participants with data on self-reported OA (N = 51 938) |
Participants with data on RKOA (N = 2589) |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Characteristics | OA (N = 3428) | No arthritis (N = 39 473) | P-valuea | Other arthritis (N = 9037) | P-valueb | RKOA (N = 1051) | No arthritis (N = 874) | P-valuec | Other arthritis (N = 664) | P-valued |
| Age (years) median (IQR) | 62 (51-72) | 38 (28-51) | 55 (22-68) | 68 (63-74) | 67 (63-73) | 68 (64-74) | ||||
| Gender, % | <0.0001 | <0.0001 | <0.0001 | 0.002 | ||||||
| Men | 33.3 | 50.4 | 39.1 | 39.3 | 52.4 | 43.0 | ||||
| Women | 66.7 | 49.6 | 60.9 | 60.7 | 47.6 | 57.0 | ||||
| Race/ethnicity, % | <0.0001 | <0.0001 | <0.0001 | <0.0001 | ||||||
| Non-Hispanic Whites | 87.4 | 70.3 | 74.3 | 79.6 | 83.7 | 83.6 | ||||
| Non-Hispanic Blacks | 5.7 | 11.4 | 13.6 | 12.1 | 5.4 | 7.5 | ||||
| Mexican-Americans | 3.5 | 12.9 | 8.5 | 5.6 | 7.9 | 6.6 | ||||
| Other | 3.4 | 5.3 | 3.6 | 2.7 | 7.6 | 2.4 | ||||
| Poverty income ratio, % | <0.0001 | <0.0001 | <0.0001 | 0.26 | ||||||
| ≤1 | 8.7 | 12.3 | 15.9 | 11.3 | 7.4 | 11.1 | ||||
| 1< to ≤3 | 36.3 | 34.8 | 40.3 | 45.4 | 43.6 | 47.2 | ||||
| >3 | 47.9 | 45.6 | 36.6 | 35.7 | 40.3 | 34.0 | ||||
| Missing | 7.1 | 7.2 | 7.2 | 7.6 | 8.7 | 7.7 | ||||
| Body mass index, % | <0.0001 | 0.004 | <0.0001 | <0.0001 | ||||||
| Normal | 24.0 | 37.3 | 26.3 | 22.7 | 42.5 | 41.5 | ||||
| Overweight | 31.8 | 30.8 | 26.5 | 39.1 | 41.3 | 39.0 | ||||
| Obese | 37.2 | 24.2 | 39.1 | 38.2 | 16.2 | 19.5 | ||||
| Missing | 7.1 | 7.7 | 8.1 | – | – | – | ||||
| Cigarette smoking, % | <0.0001 | <0.0001 | <0.0001 | <0.0001 | ||||||
| Never smoked | 46.8 | 51.5 | 41.2 | 52.6 | 41.2 | 41.3 | ||||
| Past smoker | 37.5 | 22.1 | 31.4 | 10.9 | 16.0 | 17.4 | ||||
| Current smoker | 15.6 | 26.3 | 27.4 | 36.5 | 42.8 | 41.3 | ||||
| Physical activity, % | 29.9 | 43.4 | <0.0001 | 29.3 | 0.48 | 66.2 | 71.0 | <0.0001 | 69.3 | 0.0015 |
| Diabetes, % | 15.3 | 6.2 | <0.0001 | 18.0 | 0.021 | 19.9 | 12.5 | <0.0001 | 19.3 | 0.52 |
| Hypertension, % | 56.3 | 23.5 | <0.0001 | 50.1 | 0.0003 | 52.9 | 36.8 | <0.0001 | 46.0 | <0.0001 |
| History of MI, % | 8.0 | 2.0 | <0.0001 | 8.9 | 0.24 | 11.6 | 8.9 | <0.0001 | 18.0 | <0.0001 |
| History of stroke, % | 5.9 | 1.4 | <0.0001 | 6.7 | 0.27 | 7.1 | 4.6 | <0.0001 | 10.1 | <0.0001 |
| Mortality rate/1000 person-years | ||||||||||
| All-cause | 40.9 | 13.9 | <0.0001 | 38.9 | 0.12 | 67.0 | 56.0 | 0.0006 | 59.5 | 0.052 |
| CVD | 9.7 | 3.2 | <0.0001 | 9.5 | 0.77 | 18.7 | 14.1 | 0.006 | 13.4 | 0.007 |
| Cancer | 7.5 | 3.2 | <0.0001 | 7.9 | 0.68 | 11.1 | 13.2 | 0.15 | 10.8 | 0.84 |
| CLRD | 2.0 | 0.6 | <0.0001 | 1.8 | 0.62 | 2.5 | 2.9 | 0.63 | 4.2 | 0.052 |
| Alzheimer’s disease | 1.0 | 0.3 | <0.0001 | 1.0 | 0.77 | 1.7 | 1.1 | 0.26 | 1.3 | 0.52 |
| Diabetes | 1.4 | 0.4 | <0.0001 | 1.8 | 0.36 | 2.8 | 1.6 | 0.052 | 3.3 | 0.60 |
| Renal disease | 0.6 | 0.3 | 0.0023 | 0.9 | 0.32 | 1.3 | 1.0 | 0.53 | 1.1 | 0.74 |
CLRD, chronic lower respiratory diseases.
a
Difference in characteristics between OA and no arthritis.
b
Difference in characteristics between OA and other arthritis.
c
Difference in characteristics between RKOA and no arthritis.
d
Difference in characteristics between OA and other arthritis.
P-values for differences in proportions or means by osteoarthritis status calculated using chi-square test for categorical variables and Student’s t test for continuous variables.