Table 3. Trends in Weighted Mean Hours per Day of Sedentary Behavior by NHANES Cycle, 2007-2016.
| Characteristic | Adjusted Mean (SE)a | P Value | |||||
|---|---|---|---|---|---|---|---|
| 2007-2008 (n = 5499) | 2009-2010 (n = 5893) | 2011-2012 (n = 5178) | 2013-2014 (n = 5498) | 2015-2016 (n = 5275) | Linear Trendb | Interactionc | |
| Overalla | 5.7 (0.3) | 5.9 (0.2) | 6.0 (0.2) | 7.9 (0.4) | 6.4 (0.2) | <.001 | NA |
| Age, y | |||||||
| 18-29 | 5.8 (0.2) | 6.0 (0.2) | 6.1 (0.3) | 7.9 (0.5) | 6.5 (0.2) | <.001 | .01 |
| 30-39 | 5.5 (0.3) | 6.1 (0.2) | 5.9 (0.2) | 7.8 (0.4) | 5.8 (0.3) | <.001 | |
| 40-49 | 5.4 (0.3) | 5.5 (0.2) | 6.0 (0.2) | 7.9 (0.4) | 6.2 (0.3) | <.001 | |
| 50-64 | 5.8 (0.3) | 5.9 (0.2) | 6.0 (0.2) | 7.9 (0.4) | 6.1 (0.2) | <.001 | |
| ≥65 | 6.0 (0.3) | 5.9 (0.2) | 6.1 (0.2) | 7.9 (0.4) | 6.0 (0.3) | <.001 | |
| P value for aged | .003 | .007 | .59 | .89 | .02 | NA | NA |
| Sex | |||||||
| Male | 5.7 (0.3) | 6.0 (0.2) | 6.1 (0.2) | 7.9 (0.4) | 6.2 (0.2) | <.001 | .64 |
| Female | 5.7 (0.3) | 5.8 (0.2) | 6.0 (0.2) | 7.9 (0.4) | 6.1 (0.3) | <.001 | |
| P value for sex | .90 | .07 | .39 | .50 | .58 | NA | NA |
| Race/ethnicity | |||||||
| Non-Hispanic white | 5.9 (0.2) | 6.2 (0.2) | 6.3 (0.2) | 8.0 (0.5) | 6.6 (0.2) | <.001 | .08 |
| Non-Hispanic black | 5.8 (0.2) | 5.8 (0.2) | 6.4 (0.3) | 8.5 (0.4) | 6.3 (0.2) | <.001 | |
| Hispanic | 5.0 (0.3) | 5.0 (0.2) | 5.0 (0.2) | 7.1 (0.4) | 5.4 (0.3) | <.001 | |
| Other | 6.0 (0.5) | 6.5 (0.2) | 6.3 (0.2) | 8.0 (0.4) | 6.2 (0.2) | .03 | |
| P value for raced | <.001 | <.001 | <.001 | <.001 | <.001 | NA | NA |
| Educational level | |||||||
| Less than high school | 4.6 (0.3) | 5.1 (0.2) | 5.5 (0.3) | 7.5 (0.4) | 5.5 (0.2) | <.001 | <.001 |
| High school | 4.9 (0.3) | 5.3 (0.2) | 5.6 (0.4) | 7.7 (0.4) | 6.0 (0.2) | <.001 | |
| College or above | 5.8 (0.3) | 6.1 (0.2) | 6.5 (0.3) | 8.2 (0.4) | 6.5 (0.2) | <.001 | |
| P value for educational leveld | <.001 | <.001 | <.001 | <.001 | <.001 | NA | NA |
| IPR | |||||||
| ≤1.3 | 5.3 (0.3) | 5.7 (0.2) | 5.6 (0.2) | 7.6 (0.4) | 6.0 (0.3) | <.001 | .07 |
| >1.3-3.5 | 5.6 (0.2) | 5.7 (0.2) | 5.8 (0.3) | 7.6 (0.4) | 6.2 (0.3) | <.001 | |
| >3.5 | 6.4 (0.3) | 6.5 (0.3) | 6.6 (0.2) | 8.3 (0.4) | 6.5 (0.2) | <.001 | |
| P value for IPRd | <.001 | .56 | <.001 | <.001 | .03 | NA | NA |
| Smoking status | |||||||
| Nonsmoker | 6.0 (0.2) | 6.1 (0.3) | 6.0 (0.3) | 7.4 (0.2) | 6.2 (0.2) | <.001 | .51 |
| Current smoking | 6.0 (0.3) | 6.4 (0.4) | 6.2 (0.3) | 7.2 (0.3) | 6.0 (0.2) | <.001 | |
| Ever smoker | 6.2 (0.3) | 6.2 (0.3) | 6.2 (0.2) | 7.4 (0.2) | 6.2 (0.2) | <.001 | |
| P value for smokingd | .01 | .11 | .68 | .45 | .52 | NA | NA |
| Alcohol intakee | |||||||
| Nondrinking | 5.5 (0.3) | 5.9 (0.2) | 6.2 (0.2) | 7.8 (0.4) | 6.1 (0.2) | <.001 | .06 |
| Moderate drinking | 5.9 (0.3) | 6.0 (0.3) | 5.9 (0.3) | 7.7 (0.5) | 5.8 (0.3) | .12 | |
| Heavy drinking | 5.6 (0.3) | 5.8 (0.2) | 5.8 (0.2) | 7.9 (0.4) | 6.1 (0.2) | <.001 | |
| P value for alcohold | .46 | .68 | .05 | .25 | .24 | NA | NA |
| BMI categories | |||||||
| Underweight | 5.1 (0.4) | 5.7 (0.4) | 5.5 (0.5) | 7.6 (0.5) | 5.1 (0.5) | 0.23 | .84 |
| Normal | 5.1 (0.2) | 5.0 (0.2) | 5.5 (0.2) | 7.3 (0.5) | 5.6 (0.2) | <.001 | |
| Overweight | 5.4 (0.2) | 5.3 (0.1) | 5.8 (0.2) | 7.4 (0.4) | 5.9 (0.2) | <.001 | |
| Obesity | 5.8 (0.2) | 5.8 (0.2) | 6.2 (0.1) | 8.0 (0.4) | 6.4 (0.2) | <.001 | |
| P value for BMId | <.001 | <.001 | .01 | .003 | <.001 | NA | NA |
Abbreviations: BMI, body mass index; IPR, income to poverty ratio; NA, not applicable; NHANES, National Health and Nutrition Examination Survey.
Data are presented as adjusted means (SEs) estimated by multivariable linear regression analysis, adjusted for all covariates except stratification, and are weighted.
Multivariable linear regression models include NHANES cycle as a continuous term adjusted for all covariates.
P values for interaction between socioeconomic variables and trend variable in multivariable linear regression analyses adjusted for all covariates.
P values for homogeneity estimated by the adjusted Wald F test with Bonferroni correction for multiple comparisons in multivariable linear regression analyses adjusted for all covariates.
Nondrinking, 0 g/d; moderate drinking, 0.1 to 27.9 g/d for men and 0.1 to 13.9 g/d for women; and heavy drinking, 28.0 g/d or more for men and 14.0 g/d or more for women.