Table 2 Logistic regression analysis of overall malignancy risk and COX regression analysis of the risk of neoplasia onset over 22 years of follow-up after ACS with the interaction for risks between six geographic areas and by smoking habit

Logistic regression analysis (n = 586)

OR (95 % CI)

P -value

OR (95 % CI)

P -value

Urban-rural areas

3.4 (1.7–7.1)

0.001

3.4 (1.6–7.3)

0.001*

North-south provinces

1.5 (1.0-2.2)

0.06

1.4 (0.9–2.1)

0.11*

Interaction (urban/rural areas and south to north provinces)

2.1 (1.2–3.6)

0.003

2.1 (1.2–3.6)

0.003*

Smoking habit

2.5 (1.6–4.1)

< 0.0001

2.4 (1.3–4.6)

0.006†

Cox regression analysis (n = 526)

HR (95 % CI)

Z

P -value

HR (95 % CI)

Z

P -value

Urban-rural areas

3.0 (1.5–6.2)

3.1

0.002

3.2 (1.6–6.6)

3.2

0.001*

North-south provinces

1.3 (1.0–2.0)

1.5

0.14

1.4 (1.0-2.1)

1.8

0.08*

Interaction (urban/rural areas and south to north provinces)

2.1 (1.3–3.5)

3.1

0.002

2.2 (1.4–3.6)

3.2

0.001*

Smoking habit

1.8 (0.8-4.0)

1.5

0.13

2.9 (1.2–7.21)

2.4

0.01†