Skip to main content

Table 3 Additive and multiplicative interaction effects between TPA and sedentary time on the dementia incidence

From: The independent and joint association of accelerometer-measured physical activity and sedentary time with dementia: a cohort study in the UK Biobank

TPA, milli-g

Sedentary time, hours/ day

Events/N

Incidence rate (per 1000 person-years)

HR (95% CI)

P value

Additive interaction (RERI)

Multiplicative interaction

Estimates (95% CI)

P value

Estimates (95% CI)

P value

All-cause dementia

    

0.25 (− 0.26, 0.77)

0.335

1.31 (0.79, 2.18)

0.295

 High

Low

109/34371

0.46

Ref

     

 High

High

23/10769

0.31

0.78 (0.50, 1.22)

0.274

    

 Low

Low

96/11068

1.28

1.62 (1.23, 2.15)

0.001

    

 Low

High

273/34112

1.18

1.65 (1.31, 2.09)

 < 0.001

    

Alzheimer’s disease

    

0.26 (− 0.51, 1.03)

0.502

1.42 (0.64, 3.17)

0.391

 High

Low

47/34371

0.20

Ref

     

 High

High

9/10769

0.12

0.74 (0.36, 1.52)

0.413

    

 Low

Low

39/11068

0.52

1.51 (0.98, 2.32)

0.062

    

 Low

High

104/34112

0.45

1.51 (1.06, 2.17)

0.024

    

Vascular dementia

    

0.33 (− 0.48, 1.13)

0.427

1.74 (0.53, 5.69)

0.359

 High

Low

27/34371

0.11

Ref

     

 High

High

4/10,769

0.05

0.52 (0.18, 1.50)

0.226

    

 Low

Low

18/11068

0.24

1.07 (0.58, 1.97)

0.828

    

 Low

High

45/34112

0.19

0.92 (0.55, 1.52)

0.738

    
  1. Models were adjusted for age at baseline, sex, ethnicity, education and Townsend deprivation index, smoking status, alcohol intake frequency, body mass index (BMI), history of cardiovascular disease (CVD), hypertension, diabetes, cancer and depression
  2. Abbreviations: TPA, total volume of physical activity; milli-g, RERI relative excess risk due to interaction