Contribution of MTHFR gene variants in lupus related subclinical atherosclerosis.

OBJECTIVE: Elevated concentrations of homocysteine have been previously identified as an independent risk factor for subclinical atherosclerosis in patients with systemic lupus erythematosus (SLE). Given that heightened homocysteine levels are known to be strongly influenced by genetic factors, in the current study we investigated the contribution of high homocysteine levels as well as of functional polymorphisms of the gene encoding for the enzyme 5, 10- methylenetetrahydrofolate reductase (MTHFR) to atherosclerotic disease characterizing SLE patients. METHODS: Peripheral DNA samples from 150 SLE patients, 214 rheumatoid arthritis (RA) patients and 561 age/sex matched apparently healthy volunteers (HC) were genotyped by PCR-based assays for the detection of the MTHFR gene polymorphisms (c. 677C > T and c. 1298A > C). All SLE patients and 30 age sex matched RA patients underwent assessment for subclinical atherosclerosis [ultrasound measurement of intima-media thickness scores (IMT) and detection of carotid and/or femoral (C/F) plaque] and complete clinical and laboratory evaluation including serum homocysteine levels. Data were analyzed using univariate and multivariate models (SPSS 21.0). RESULTS: Hyperhomocysteinemia was detected in 26.0% of SLE patients compared to 6.7% of age/sex matched RA controls (p = 0.02). Higher serum B12 levels and decreased frequency of the MTHFR 677TT variant in RA patients could potentially account for the observed differences between the groups. In SLE patients, both hyperhomocysteinemia and MTHFR 677TT genotype were identified as independent contributors for plaque formation, following adjustment for traditional cardiovascular risk factors and disease related features, including age, sex, BMI, cholesterol and triglyceride levels, presence of arterial hypertension, smoking (pack/years), disease duration and total steroid dose [OR 95% (CI): 5.8 (1.0-35.8) and 5.2 (1.1-24.0), respectively]. MTHFR 677TT genotype, but not hyperhomocysteinemia was also found to confer increased risk for arterial wall thickening, after the above confounders were taken into account [OR (95%) CI: 4.9 (1.2-20.6)]. CONCLUSIONS: Hyperhomocysteinemia and MTHFR 677TT genetic variant emerged as independent risk factors for subclinical atherosclerosis in SLE patients, implying genetic influences as potential contributors to the increased burden of atherosclerotic disease characterizing SLE.

Anxiety and Extraversion in Lupus-Related Atherosclerosis.

Objectives: Patients with systemic lupus erythematosus (SLE) are characterized by increased cardiovascular disease (CVD) risk as well as heightened rates of psychological distress. Since a link between psychological issues and CV morbidity has been previously suggested, the influence of psychological burden on subclinical atherosclerosis in SLE patients was investigated. Methods: 71 SLE patients were assessed for the presence of subclinical atherosclerosis-defined either as carotid and/or femoral plaque formation or arterial wall thickening [Intima Media Thickness (IMT) levels > 0.90 mm by Doppler ultrasound]; personality traits, anxiety and depression, sleeping habits and fatigue levels were also evaluated by specific questionnaires including Eysenck Personality Questionnaire Scale, State-Trait Anxiety Inventory (STAI), Zung Depression Scale, Athens Insomnia Scale and Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F). Disease related clinical and laboratory features and traditional risk factors for atherosclerosis were documented. Univariate and multivariate analysis were performed. Results: SLE patients with arterial wall thickening displayed higher STAI anxiety scores (either as a current state or as a personality trait) compared to those without (49.8 ± 5.6 vs. 46.9 ± 5.4, p-value: 0.03 and 49.2 ± 4.4 vs. 45.7 ± 6.8, p-value: 0.009, respectively). In a multivariate model, trait anxiety and extraversion personality scores were found to be independently associated with arterial wall thickening and plaque formation, respectively [OR95%(CI):1.2(1.0-1.5) and 0.7(0.6-1.0), respectively], following adjustment for potential confounders. No other associations were detected. Conclusions: Anxiety and extraversion personality traits have been independently associated with subclinical atherosclerosis in lupus patients, implying psychoneuroimmunological interactions as contributors in SLE related atherosclerosis.