HLA-DRB1*1501 intensifies the impact of IL-6 promoter polymorphism on the susceptibility to multiple sclerosis in an Iranian population.

BACKGROUND: The multifunctional cytokine interleukin-6 (IL-6) is involved in inflammatory processes in the central nervous system. It is well documented that amount of IL-6 is increased in serum, cerebrospinal fluid and central nervous system lesions of patients with multiple sclerosis. A single nucleotide polymorphism at position -174 in the IL-6 gene promotor appears to influence IL-6 expression. Recently, several researchers have focused on HLA-DRB alleles, specifically HLA-DRB1*1501, as a potential risk allele in the pathogenesis of multiple sclerosis. OBJECTIVE: To investigate the possible influence of IL-6/-174 polymorphisms on susceptibility to multiple sclerosis and its integration with HLA-DRB1*1501. Genomic DNA was extracted from whole blood of 345 patients with multiple sclerosis and 426 control subjects. METHOD: The SSP-PCR method was used to determine genotypes and Fisher's exact test was applied to determine differences between groups. HLA-DRB1*1501 was observed more frequently among multiple sclerosis patients compared with healthy subjects (45% and 34%, respectively; OR = 1.6, 95% CI = 1.2-2.2, p = 0.0018). At the IL-6/-174 position, the G allele had higher frequency among multiple sclerosis patients compared with controls (77% and 70%, respectively; OR = 1.4, 95% CI = 1.1-1.8, p = 0.0038). This difference was more significant among HLA-DRB1*1501-positive patients and controls (81% and 67%, respectively; OR = 1.9, 95% CI = 1.5-2.5, p < 0.0001). RESULTS: Our results have shown that the G allele at the IL-6/-174 promoter polymorphism may be associated with development of multiple sclerosis in this population, and may be strengthened by HLA-DRB1*1501. CONCLUSIONS: We suggest more studies to confirm these results in other populations.

A cost analysis of gastro-oesophageal reflux disease and dyspepsia in Iran.

BACKGROUND AND AIM: To provide a first-time report on the health care utilization and costs of gastro-oesophageal reflux disease and dyspepsia in Iran. METHODS: A consecutive sample of 501 patients referred for upper endoscopy to an outpatient gastroenterology clinic in central Tehran (May 2005 to January 2006) was investigated using two interview-assisted questionnaires for gastro-oesophageal reflux disease (i.e. heartburn or regurgitation on a weekly basis for at least the past 3 months, and symptom onset at least 12 months prior to the study) or dyspepsia symptom (based on Rome II criteria). The frequency of health resource utilization (i.e. physician visit, hospitalization, laboratory tests, instrumental studies, and medications) and productivity loss (days off work) due to gastro-oesophageal reflux disease/dyspepsia-related symptoms in the past 12 months were recorded. Societal perspective was used, and cost of illness per person per year was estimated in purchasing power parity dollars (PPP$). RESULTS: The cost of illness per person per year for patients with gastro-oesophageal reflux disease, and dyspepsia alone were around PPP$195 and PPP$215, respectively. There was no statistically significant difference in the cost of illness between the two patient groups. The direct costs of disease comprised 88%, and 82% of the total costs in gastro-oesophageal reflux disease and dyspepsia patients, respectively with the costs of medications being the dominant component. There was also no statistically significant difference in the cost of disease between the gastro-oesophageal reflux disease patients with and without oesophagitis (based on Los Angeles criteria). CONCLUSION: As drugs cost was found to be a dominant cost component, cost-minimization studies to find the best medication therapy strategies considering the regional factors is suggested.