Association of 25-hydroxyvitamin D with liver cancer incidence and chronic liver disease mortality in Finnish male smokers of the ATBC study
Menée en Finlande à partir de données portant sur 202 patients atteints d'un cancer du foie et sur 427 témoins, cette étude évalue l'association entre le niveau sérique de 25-hydroxyvitamine D, le risque de développer la maladie et la mortalité par maladie chronique du foie chez des hommes fumeurs (durée moyenne de suivi : 25 ans ; 225 décès par maladie chronique du foie)
Background: Although circulating 25-hydroxyvitamin D [25(OH)D] concentrations were linked to liver cancer and chronic liver disease (CLD) in laboratory studies, few epidemiologic studies have addressed the associations. Methods: Within the ATBC Study, we measured 25(OH)D in baseline serum of 202 incident liver cancer cases and 225 CLD deaths that occurred during nearly 25 years of follow-up, and 427 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression. We examined pre-determined clinically defined cut-points, and season-specific and season-standardized quartiles. Results: Low serum 25(OH)D concentrations were associated with higher risk of liver cancer (<25 nmol/L versus ≥50 nmol/L: 1.98, 95% CI: 1.22-3.20; p-trend across categories=0.003) and CLD mortality (1.93, 1.23-3.03; p-trend=0.006) in models adjusted for age and date of blood draw. After additional adjustment for BMI, diabetes, smoking, and other potential confounders, the association remained statistically significant for liver cancer (1.91, 1.16-3.15, p-trend=0.008), but was somewhat attenuated for CLD mortality (1.67, 1.02-2.75; p-trend=0.05). Associations were similar for analyses using season-specific and season-standardized quartiles, and after excluding participants with diabetes, or hepatitis B or C. Conclusions: Our results suggest a possible preventive role for vitamin D against liver cancer and CLD, although the importance of the liver for vitamin D metabolism and the lack of information about underlying liver disease makes reverse causality a concern. Impact: Future studies are needed to evaluate associations of vitamin D with liver cancer and disease in other populations, particularly those with a different constellation of risk factors.