Table 3.
Exercise intervention effects on inflammatory cytokines in the Alberta Physical Activity and Breast Cancer Prevention Trial (ALPHA), stratified by potential moderators
| Potential moderatora | IL‐4b | IL‐10b | ||
|---|---|---|---|---|
| Baseline level | n c | TERd | n c | TERd |
| Physical fitness (VO2max) | ||||
| <27.5 mL/kg/min | 72/76 | 0.95 (0.86, 1.04) | 73/75 | 0.91 (0.82, 1.01) |
| ≥27.5 | 75/74 | 1.02 (0.93, 1.12) | 74/75 | 1.09 (0.96, 1.23) |
| P e = 0.66 | P e < 0.01 | |||
| Age | ||||
| ≤60 years | 73/68 | 1.05 (0.95, 1.15) | 73/68 | 1.05 (0.92, 1.20) |
| >60 | 74/82 | 0.92 (0.84, 1.01) | 74/82 | 0.94 (0.85, 1.04) |
| P e = 0.38 | P e = 0.07 | |||
| Past year recreational activity | ||||
| <7.1 MET‐h/week | 69/78 | 1.02 (0.93, 1.12) | 70/78 | 1.02 (0.92, 1.13) |
| ≥7.1 | 78/72 | 0.94 (0.85, 1.03) | 77/72 | 0.96 (0.84, 1.09) |
| P e = 0.29 | P e = 0.28 | |||
| BMI | ||||
| <25 kg/m2 | 28/32 | 1.03 (0.90, 1.18) | 29/32 | 1.12 (0.88, 1.42) |
| 25–<30 | 62/60 | 0.96 (0.86, 1.06) | 61/61 | 1.01 (0.90, 1.14) |
| ≥30 | 76/71 | 0.98 (0.87, 1.09) | 76/72 | 0.91 (0.81, 1.02) |
| P e = 0.45 | P e = 0.04 | |||
| Body fat percentage | ||||
| <42.2% | 71/77 | 0.99 (0.90, 1.09) | 72/77 | 1.02 (0.92, 1.13) |
| ≥42.2 | 76/73 | 0.97 (0.89, 1.07) | 75/73 | 0.97 (0.85, 1.10) |
| P e = 0.40 | P e = 0.26 | |||
| Baseline IL‐4 | ||||
| <0.50 pg/mL | 71/79 | 1.04 (0.94, 1.15) | ||
| ≥0.50 | 76/71 | 0.92 (0.85, 1.00) | ||
| P e = 0.45 | ||||
| Baseline IL‐10 | ||||
| <0.36 pg/mL | 71/78 | 1.09 (0.95, 1.24) | ||
| ≥0.36 | 76/72 | 0.90 (0.82, 0.98) | ||
| P e = 0.03 | ||||
BMI, body mass index; CI, confidence interval; IL‐4, interleukin‐4; IL‐10, interleukin‐10 ; TER, treatment effect ratio.
Level of potential moderator at baseline.
Of the 310 participants who provided a blood sample at any time point, we excluded those with IL‐4 or IL‐10 levels above a threshold for extremely high levels, specifically: 10 pg/mL for both IL‐4 (n = 5 excluded) and IL‐10 (n = 5 excluded). Participants (n = 8) missing a blood sample at any time point were also removed.
Number of exercisers/number of controls.
The TER represents the adjusted ratio of geometric means for the exercise group over the control group. A TER of <1.0 indicates lower anti‐inflammatory cytokine levels in the exercise group relative to the control group at 6 and 12 months; a TER greater than 1 indicates higher anti‐inflammatory cytokine levels in the exercise group; and a TER of 1.0 indicates no differences between the groups.
P‐value refers to the statistical significance of the interaction term between the exercise group and the potential moderator. All moderators were treated as continuous variables.