Table 4. Prospective Association of Factors With Sedentary Behavior and Physical Activity Among Women at 20 Years and 9 Yearsa.
| Factor | 20-y Follow-up (n = 985) | 9-y Follow-up (n = 954) | ||||||
|---|---|---|---|---|---|---|---|---|
| Mean time difference (95% CI), min/db | P value for activity distributionc | Mean time difference (95% CI), min/db | P value for activity distributionc | |||||
| SB | LIPA | MVPA | SB | LIPA | MVPA | |||
| Sociodemographic factor | ||||||||
| Age, per 5 y | 16.6 (11.4 to 21.9) | −6.0 (−10.1 to −1.8) | −10.7 (−12.6 to −8.7) | <.001d | 18.9 (13.5 to 24.4) | −7.5 (−11.8 to −3.2) | −11.5 (−13.5 to −9.4) | <.001d |
| Member of racial or ethnic minority groupe | 9.2 (−10.3 to 28.7) | −4.8 (−20.0 to 10.5) | −4.4 (−11.6 to 2.8) | <.001d | 8.5 (−12.0 to 28.9) | −3.7 (−19.8 to 12.4) | −4.8 (−12.4 to 2.8) | <.001d |
| Lower occupational positionf | −9.3 (−27.7 to 9.2) | 11.3 (−3.1 to 25.7) | −2.0 (−8.8 to 4.8) | .17 | −17.4 (−36.2 to 1.3) | 14.1 (−0.7 to 28.8) | 3.4 (−3.6 to 10.3) | <.001d |
| Not married or cohabitating | 15.0 (2.9 to 27.1) | −13.8 (−23.3 to −4.3) | −1.2 (−5.7 to 3.2) | <.001d | 9.2 (−2.7 to 21.2) | −8.6 (−18.0 to 0.8) | −0.6 (−5.1 to 3.8) | <.001d |
| Behavioral factor | ||||||||
| Smoking status | ||||||||
| Never | 1 [Reference] | 1 [Reference] | 1 [Reference] | NA | 1 [Reference] | 1 [Reference] | 1 [Reference] | NA |
| Past | −4.7 (−18.1 to 8.6) | 1.8 (−8.6 to 12.2) | 3.0 (−2.0 to 7.9) | .84 | −0.3 (−12.9 to 12.3) | −0.8 (−10.7 to 9.2) | 1.1 (−3.6 to 5.8) | .33 |
| Current | 11.6 (−7.5 to 30.7) | −4.5 (−19.4 to 10.4) | −7.1 (−14.1 to −0.1) | .002d | 10.0 (−12.4 to 32.3) | 0.1 (−17.5 to 17.7) | −10.0 (−18.4 to −1.7) | <.001d |
| Alcohol intakeg | ||||||||
| None | 14.1 (−0.2 to 28.3) | −11.1 (−22.2 to 0.0) | −3.0 (−8.2 to 2.3) | <.001d | 16.5 (1.9 to 31.2) | −12.6 (−24.1 to −1.1) | −4.0 (−9.4 to 1.5) | <.001d |
| Moderate | 1 [Reference] | 1 [Reference] | 1 [Reference] | NA | 1 [Reference] | 1 [Reference] | 1 [Reference] | NA |
| High | 0.9 (−18.8 to 20.6) | −2.4 (−17.8 to 13.0) | 1.5 (−5.8 to 8.7) | .15 | 1.3 (−16.0 to 18.6) | −5.6 (−19.2 to 7.9) | 4.3 (−2.1 to 10.8) | <.001d |
| Fruit and vegetable intake < twice daily | 7.8 (−5.2 to 20.8) | −6.3 (−16.5 to 3.9) | −1.5 (−6.3 to 3.3) | <.001d | 9.8 (−2.7 to 22.4) | −8.3 (−18.2 to 1.5) | −1.5 (−6.2 to 3.2) | <.001d |
| Health-related factor | ||||||||
| BMIh | ||||||||
| Reference range | 1 [Reference] | 1 [Reference] | 1 [Reference] | NA | 1 [Reference] | 1 [Reference] | 1 [Reference] | NA |
| Overweight | 34.8 (21.5 to 48.1) | −20.4 (−30.8 to −10.0) | −14.4 (−19.3 to −9.5) | <.001d | 22.9 (9.4 to 36.5) | −11.1 (−21.8 to −0.4) | −11.9 (−16.9 to −6.8) | <.001d |
| Obese | 44.8 (26.1 to 63.6) | −27.8 (−42.5 to −13.2) | −17.0 (−23.9 to −10.1) | <.001d | 45.1 (29.8 to 60.5) | −27.3 (−39.4 to −15.2) | −17.9 (−23.6 to −12.1) | <.001d |
| MCS, per 10-point decreasei | 8.4 (2.0 to 14.8) | −4.9 (−9.9 to 0.1) | −3.5 (−5.8 to −1.1) | <.001d | 7.5 (1.6 to 13.5) | −5.1 (−9.8 to −0.4) | −2.4 (−4.7 to −0.2) | <.001d |
| PCS, per 10-point decreasei | 6.7 (−0.9 to 14.2) | −1.8 (−7.6 to 4.1) | −4.9 (−7.7 to −2.1) | <.001d | 7.4 (1.0 to 13.7) | −2.9 (−7.9 to 2.0) | −4.4 (−6.8 to −2.1) | <.001d |
| No. of chronic conditions, per new conditionj | 8.4 (−5.6 to 22.4) | −6.2 (−17.2 to 4.7) | −2.1 (−7.3 to 3.0) | .10 | 11.4 (3.7 to 19.0) | −8.8 (−14.9 to −2.8) | −2.5 (−5.4 to 0.3) | <.001d |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); LIPA, light-intensity physical activity; MCS, mental component summary score from the 36-Item Short Form Health Survey; MVPA, moderate to vigorous physical activity; NA, not applicable; PCS, physical component summary score from the 36-Item Short Form Health Survey; SB, sedentary behavior.
Associations are between factors as measured in 1991 to 1993 (for 20 years of follow-up) or 2002 to 2004 (for 9 years of follow-up) and outcomes measured in 2012 to 2013.
Estimated from linear regression adjusted for all covariates and waking time.
P for association between each factor and activity intensity distribution from function-on-scalar regression adjusted for covariates and waking time.
P values < .004 were considered significant according to the Bonferroni correction for multiple testing.
Race and ethnicity were assessed by questionnaire using the response categories Black, South Asian, White, and other. Racial and ethnic minority groups have been combined in analysis owing to small numbers.
Last occupational position was defined as low (clerical or support positions), intermediate (professional or executive positions), or high (administrative positions), coded as 1, 0.5, and 0, respectively, and entered as an ordinal variable in analyses.
Alcohol intake was defined as 0 units/wk for none, 1 to 14 units/wk for moderate, and more than 14 units/wk for high.
BMI categories were defined as less than 25 for reference range, 25 to 29.9 for overweight, and 30 or more for obese.
Lower MCS and PCS correspond to poorer mental and physical summary score, respectively.
Chronic conditions include hypertension, diabetes, coronary heart disease, stroke, heart failure, arthritis, cancer, depression, dementia, Parkinson disease, and chronic obstructive pulmonary disease.