Table 1. Regular Aspirin Use and Risk of Hepatocellular Carcinoma Among 133 371 Women and Men in the NHS (1980-2012) and HPFS (1986-2012) Cohorts.
| Characteristic | Aspirin Use | |
|---|---|---|
| Nonregular | Regulara | |
| Women | ||
| Cases per person-years | 44/1 900 916 | 21/1 229 095 |
| Age-adjusted HR (95% CI) | 1 [Reference] | 0.53 (0.32-0.90) |
| Model 2 (95% CI)b | 1 [Reference] | 0.49 (0.29-0.84) |
| Model 3 (95% CI)c | 1 [Reference] | 0.49 (0.28-0.83) |
| Men | ||
| Cases per person-years | 27/593 041 | 16/509 136 |
| Age-adjusted HR (95% CI) | 1 [Reference] | 0.55 (0.29-1.02) |
| Model 2 (95%CI)b | 1 [Reference] | 0.54 (0.30-1.01) |
| Model 3 (95% CI)c | 1 [Reference] | 0.54 (0.30-1.02) |
| Pooled | ||
| Cases per person-years | 71/2 493 957 | 37/1 738 231 |
| Age-adjusted HR (95% CI) | 1 [Reference] | 0.54 (0.36-0.80) |
| Model 2 (95% CI)b | 1 [Reference] | 0.51 (0.34-0.77) |
| Model 3 (95% CI)c | 1 [Reference] | 0.51 (0.34-0.77) |
Abbreviations: HPFS, Health Professionals Follow-up Study; HR, hazard ratio; NHS, Nurses’ Health Study.
Regular aspirin use was defined as consumption of 2 or more standard-dose (325-mg) aspirin tablets or more per week (vs nonregular use) and modeled as a time-varying covariate.
Model 2 was conditioned on age (continuous years) and year of questionnaire return, and adjusted for sex (ie, cohort), race/ethnicity (white vs nonwhite), body mass index (continuous measure), alcohol intake (0-4.9, 5.0-14.9, ≥15.0 g/d), smoking status (current vs prior vs never), physical activity (<3.0, 3.0-8.9, ≥9.0 metabolic equivalent task hours per week), diabetes (yes vs no), hypertension (yes vs no), dyslipidemia (yes vs no), regular multivitamin use (≥2 multivitamin tablets per week vs no), regular use of oral antidiabetic medications (yes vs no) and regular use of statins (yes vs no). All relevant covariates were updated over time.
Model 3 includes model 2 covariates plus regular use of nonaspirin nonsteroidal anti-inflammatory drugs (≥2 nonaspirin nonsteroidal anti-inflammatory drug tablets per week vs none), assessed as a time-varying covariate.