Skip to main content

Table 3 Relative risk of rheumatoid arthritis by different activity status among women from the Swedish Mammography Cohort, follow-up 2003 to 2010

From: Physical activity and risk of rheumatoid arthritis in women: a population-based prospective study

 

Person-years

Number of cases a /women in the cohort

Age-adjusted relative risk

95% CI

Multivariable b relative risk

95% CI

Leisure-time activity

Walking/bicycling

      

<20 minutes/day

64,615

69/8,769

1.00

 

1.00

 

≥20 minutes/day (median 40 to 60)

161,862

132/21,343

0.91

0.76 to 1.08

0.91

0.77 to 1.09

Exercise

      

<1 hour/week

42,398

46/5,770

1.00

 

1.00

 

1 hour/week

54,190

48/7,150

0.80

0.54 to 1.20

0.83

0.55 to 1.25

≥2 hours/week (median 2 to 3)

129,889

107/17,192

0.77

0.55 to 1.10

0.80

0.56 to 1.14

Leisure-time inactivity

Watching television/sitting

      

<1 hour/day

25,361

21/3,280

1.00

 

1.00

 

1 to 2 hours/day

104,213

93/13,665

1.15

0.71 to 1.84

1.11

0.69 to 1.78

>2 hours/day (median 3 to 4)

95,068

87/12,922

1.37

0.84 to 2.24

1.27

0.77 to 2.08

Other daily physical activities

Home/household work

      

<2 hours/day

86,311

83/11,364

1.00

 

1.00

 

3 to 4 hours/day

77,696

74/10,344

1.05

0.76 to 1.43

1.04

0.75 to 1.43

5 to 6 hours/day

33,313

24/4,458

0.84

0.53 to 1.33

0.84

0.53 to 1.35

>6 hours/day (median 7 to 8)

22,131

13/2,981

0.67

0.37 to 1.22

0.68

0.37 to 1.24

Work/occupation

      

Sitting

107,145

103/14,290

1.00

 

1.00

 

Walking/standing

105,432

87/13,917

0.86

0.64 to 1.14

0.85

0.63 to 1.13

Total energy expenditure (24 hours)

<38.8 MET-hours per day

48,847

45/6,567

1.00

 

1.00

 

38.8 to 42.2 MET-hours per day

51,492

47/6,792

1.00

0.66 to 1.50

1.01

0.67 to 1.53

42.2 to 45.9 MET-hours per day

51,285

44/6,800

0.94

0.62 to 1.43

0.96

0.63 to 1.46

≥45.9 MET-hours per day

52,099

46/6,851

0.97

0.64 to 1.46

0.97

0.64 to 1.47

  1. CI, confidence interval; MET, metabolic equivalent (kcal/kg per hour). aNumber of cases do not add to the total (n = 201) due to missing values for information about the single physical activities. bAdjusted for age (continuous), smoking status (categorised as never, former, current ≤10 cigarettes per day or >10 cigarettes per day), alcohol intake (never, former, current <2 drinks per week, ≥2 drinks per week), body mass index (quartiles) and educational level (<10 years, 10–12 years, >12 years, other).