Table 2 Ischemic stroke incidence rate ratios by severity and subtype associated with increases in outdoor PM ₁₀ concentration in the South London Stroke Register study area, 1995-2007

Oxford classification

TACI

473

1.03 (0.95-1.13)

1

1.02 (0.81-1.27)

1.07 (0.85-1.34)

PACI

762

1.00 (0.93-1.07)

1

0.99 (0.83-1.19)

1.06 (0.89-1.26)

POCI

362

1.00 (0.90-1.11)

1

1.05 (0.81-1.36)

1.11 (0.86-1.44)

LACI

860

0.96 (0.89-1.03)

1

0.95 (0.80-1.12)

1.00 (0.85-1.18)

TOAST classification*

Large artery atherosclerosis

136

1.05 (0.89-1.23)

1

0.90 (0.59-1.37)

1.05 (0.70-1.59)

Cardioembolism

371

1.03 (0.93-1.13)

1

1.00 (0.77-1.30)

1.15 (0.89-1.48)

Small vessel occlusion

376

0.93 (0.83-1.04)

1

1.21 (0.95-1.56)

1.04 (0.80-1.35)

NIHSS severity**

NIHSS = <6

541

0.95 (0.87-1.04)

1

1.20 (0.97-1.48)

1.09 (0.88-1.35)

NIHSS >6

510

1.03 (0.95-1.12)

1

1.06 (0.86-1.32)

1.08 (0.87-1.35)

Clinical severity

Mild

1285

1.04 (0.99-1.09)

1

1.06 (0.92-1.22)

1.20 (1.05-1.38)

Severe

1207

0.95 (0.89-1.01)

1

0.95 (0.82-1.09)

0.92 (0.80-1.06)