Table 3.
Predictive value of EBV DNA for NPC development by different follow-up duration
| Variables | > 2 years | > 3 years | > 4 years | |||
|---|---|---|---|---|---|---|
| Adjusted HR(95%CIs) | P-value | Adjusted HR(95%CIs) | P-value | Adjusted HR(95%CIs) | P-value | |
| ≤3(undetectable) | Reference | Reference | Reference | |||
| > 3 (detectable) | 10.878 (4.215–28.072) | < 0.0001a | 5.139 (1.136–23.252) | 0.0336a | 4.054 (0.500–32.845) | 0.1898a |
| > 3–999 | 9.637 (3.491–26.607) | < 0.0001b | 2.785 (0.359–21.619) | 0.3273b | 4.472 (0.552–36.257) | 0.3739b |
| ≥1000 | 30.111 (3.662–247.587) | 33.560 (3.996–281.872) | – |
aHRs are adjusted by sex, age, smoking status, NPC family history, salted food,education level; b P trend for the comparision among EBV DNA undetectable group, DNA levels at > 3–999 copies/ml and DNA levels ≥1000 copies/ml