Interleukin-10 promoter gene polymorphisms are associated with the first major depressive episode in chronic hepatitis C patients

AIMS

To investigate the association of IL10 SNPs in chronic hepatitis C (CHC) patients with and without the first major depressive episode (MDE), as well as their association with plasma levels of target cytokines.

METHODS

A hundred and thirty two CHC patients (32 with and 100 without first MDE) and 98 controls were prospectively enrolled in this cross-sectional study. MDE was diagnosed by a psychiatrist, using the Mini International Neuropsychiatric Interview Plus 5.0. IL10 polymorphisms (-1082 G/A, -819C/T and -592C/A IL10 SNPs) were evaluated by Taqman SNP genotyping assay. Plasma concentrations of IL-2, IL-6, IL-10, IFN-γ and TNF-α were determined using the Human Th1/Th2 Cytometric Bead Array kit. The associations were investigated by logistic models.

RESULTS

The frequencies of the studied IL10 SNPs did not differ between the CHC patients and controls. The first MDE was positive and independently associated with the IL10-1082*A, IL10-819*T and IL10-592*A (ATA) low producer haplotype (OR = 1.50; 95% CI = 1.11-2.04; P = 0.009) and current alcohol misuse (OR = 4.29; 95% CI = 1.22-15.05; P = 0.02), and inversely associated with increasing age (OR = 0.94; 95% CI = 0.91-0.98; P = 0.006). In addition, plasma level of TNF-α was significantly higher in the carriers than in the non-carriers of the IL10 ATA haplotype in patients with the first MDE. The IL-10 and IL-2 plasma levels were significantly higher in the carriers than in non-carriers of the IL10 GCC high producer haplotype, demonstrating the functionality of the studied IL10 polymorphisms.

CONCLUSIONS

This is the first study to demonstrate that the IL10 low producer ATA haplotype is associated with the first MDE in patients with CHC.

The combined polymorphisms of interleukin-6-174GG genotype and interleukin-10 ATA haplotype are associated with a poor quality of life in patients with chronic hepatitis C

PURPOSE

Chronic hepatitis C (CHC) is associated with a decreased health-related quality of life (HRQOL). More recent studies have pointed toward a genetic basis of patient-reported quality of life outcomes. Taking into account that the influence of single-nucleotide polymorphisms (SNPs) on the HRQOL of CHC patients has not been studied, we investigated the combined IL10-1082G/A, - 819C/T, and - 592C/A SNPs, and IL6-174G/C SNP. We also evaluated the association between demographic, clinical, psychiatric, virological, and genetic variables with domains and summaries of HRQOL in CHC patients.

METHODS

132 consecutive CHC patients and 98 controls underwent psychiatric evaluation by using the Mini International Neuropsychiatric Interview. HRQOL was assessed by a generic questionnaire, the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), and by the specific Liver Disease Quality of Life Questionnaire (LDQOL). IL6 and IL10 polymorphisms were evaluated by Taqman SNP genotyping assay. Multivariate analysis was used to evaluate the associations.

RESULTS

Major depressive disorder was associated with lower SF-36 and LDQOL scores in seven and ten domains, respectively. Diabetes and hypertension were also associated with reduced HRQOL. CHC patients carrying the combination of IL10 ATA haplotype/IL6-GG genotype had lower scores in the SF-36-physical functioning domain, and reduced scores in the LDQOL effects of liver disease on activities of daily living, quality of social interaction, and sexual function domains than the non-carriers of the combined haplotype/genotype.

CONCLUSION

This is the first study to demonstrate that combined IL6 high-producer GG genotype and IL10 low-producer ATA haplotype is associated with poorer HRQOL in CHC patients.