Publications

Black people have the highest prevalence of hypertension in the United States. Evidence suggests that psychosocial factors increase the risks for hypertension and help to account for racial differences in this condition. This article reviews research on psychosocial factors and hypertension, and contextualizes the findings within a health disparities framework. A wide range of psychosocial factors contribute to hypertension but understanding remains limited about how these factors relate to each other and accumulate to contribute to hypertension disparities. Future research on psychosocial factors and hypertension needs to enhance the effectiveness of interventions to reduce hypertension risk in ethnic minority communities.

Both BLISS-52 and BLISS-76 international phase III trials in Systemic Lupus Erythematosus (SLE) met their primary outcomes; however, they were not designed to assess the efficacy of belimumab for the treatment of lupus nephritis (LN). LN is a frequent cause of SLE-associated morbidity and mortality, and emerging evidence suggests a potential therapeutic role for agents that target B lymphocyte stimulator (BLyS). We conducted a systematic review to identify data on the effect of belimumab on LN. A total of 2004 patients with SLE were identified from 11 studies. Three hundred and twenty-six patients had LN at baseline and 234 (71.8%) of those received belimumab. Thirteen patients out of 234 (5.5%) received belimumab for active LN. Due to the heterogeneous definitions of treatment response, clinical presentation and renal involvement, it was not possible to compare results using a single outcome parameter. However, the majority of these studies defined clinical response in terms of rates of renal flare, renal remission, and/or renal organ disease improvement. One hundred twenty-nine (55.1%) of the 234 patients with LN at baseline showed an improvement in renal parameters after treatment with belimumab. In patients with baseline proteinuria>0.2g/24h, (n=687), those receiving belimumab had a median reduction in proteinuria during follow-up as high as 38%. When focusing on patients with proteinuria≥1g/24h (n=228), 70.7% of those treated with belimumab (n=157) achieved a renal response. In the pooled population of patients receiving belimumab, we found an overall annual renal flare rate of 1.7% [24/1448, mean observation time 1,1years (0,5-3)]. Despite the limitations of the studies included in this analysis, available data are promising and provide preliminary support for targeting BlyS to induce or maintain a renal response. Further trials should examine whether belimumab (alone or following rituximab) represents an additional therapeutic option in the treatment of LN.

BACKGROUND & AIMS

Celiac disease (CeD) provides an opportunity to study autoimmunity and the transition in immune cells as dietary gluten induces small intestinal lesions.

METHODS

Seventy-three celiac disease patients on a long-term, gluten-free diet ingested a known amount of gluten daily for 6 weeks. A peripheral blood sample and intestinal biopsy specimens were taken before and 6 weeks after initiating the gluten challenge. Biopsy results were reported on a continuous numeric scale that measured the villus-height-to-crypt-depth ratio to quantify gluten-induced intestinal injury. Pooled B and T cells were isolated from whole blood, and RNA was analyzed by DNA microarray looking for changes in peripheral B- and T-cell gene expression that correlated with changes in villus height to crypt depth, as patients maintained a relatively healthy intestinal mucosa or deteriorated in the face of a gluten challenge.

RESULTS

Gluten-dependent intestinal damage from baseline to 6 weeks varied widely across all patients, ranging from no change to extensive damage. Genes differentially expressed in B cells correlated strongly with the extent of intestinal damage. A relative increase in B-cell gene expression correlated with a lack of sensitivity to gluten whereas their relative decrease correlated with gluten-induced mucosal injury. A core B-cell gene module, representing a subset of B-cell genes analyzed, accounted for the correlation with intestinal injury.

CONCLUSIONS

Genes comprising the core B-cell module showed a net increase in expression from baseline to 6 weeks in patients with little to no intestinal damage, suggesting that these individuals may have mounted a B-cell immune response to maintain mucosal homeostasis and circumvent inflammation. DNA microarray data were deposited at the GEO repository (accession number: GSE87629; available: https://www.ncbi.nlm.nih.gov/geo/).

BACKGROUND

Hepatic steatosis is increasing worldwide. Whether HIV and its associated metabolic perturbations exacerbate steatosis is unclear. Sex differences in adipose tissue distribution may also affect steatosis risk. We examined the contribution of HIV and sex to steatosis.

METHODS

Using MRI and spectroscopy, visceral adipose tissue (VAT) and liver fat fraction (LFF) were measured in 121 HIV-infected and 107 uninfected men and women without viral hepatitis. Differences in LFF by HIV status and sex were evaluated using multivariable linear regression, adjusting for demographic, lifestyle, VAT, homeostasis model assessment-estimated insulin resistance, and HIV-related factors.

RESULTS

HIV-infected women had lower LFF than uninfected women (demographic-adjusted mean: 1.9 vs. 3.1%; P = 0.028); LFF was similar in HIV-infected and uninfected men (4.6 vs. 4.1%; P = 0.78). HIV-infected and uninfected women had less VAT than men (median: 139 and 161 vs. 201 cm and 188 cm, respectively). After adjustment, HIV-infected women had 34% [95% confidence interval (CI): -54%, -5.5%] lower LFF than uninfected women, whereas there was little difference in men (-5.5%; 95% CI: -26%, 21%). Among HIV-infected persons, greater VAT and homeostasis model assessment-estimated insulin resistance were associated with greater LFF. HIV-related factors (CD4 cell count, HIV RNA level, or antiretroviral therapy use) had little association with LFF. Although HIV-infected men had 81% (95% CI: 32%, 148%) greater LFF than HIV-infected women, the association was attenuated after multivariable adjustment (25%; 95% CI: -9.1%, 73%).

CONCLUSION

Contrary to expectation, HIV infection is not associated with greater steatosis compared with uninfected adults. It is possible that less fat is stored in the liver to maintain subcutaneous fat (which is reduced in HIV) and the effect is magnified in HIV-infected women, who also have less VAT.

OBJECTIVES

HIV/hepatitis C virus (HCV) coinfection is associated with insulin resistance, but the mechanism is unclear. We hypothesized that intestinal epithelial damage and the consequent monocyte/macrophage activation and inflammation explain this perturbation.

DESIGN

Cross-sectional study of 519 adults (220 HIV+/HCV-; 64 HIV-/HCV+; 89 HIV+/HCV+; 146 HIV-/HCV-).

METHODS

We used multivariable linear regression to evaluate associations of HIV and HCV with the homeostasis model assessment of insulin resistance (HOMA-IR) and if intestinal fatty (FA) acid binding protein (I-FABP, a marker of gut epithelial integrity), soluble CD14 (sCD14) and soluble CD163 (sCD163) (markers of monocyte/macrophage activation), and IL-6 (an inflammatory cytokine) mediated this association.

RESULTS

HIV+/HCV+ and HIV-/HCV+ had greater demographic-adjusted HOMA-IR [mean (95% confidence interval (CI)): 1.96 (1.51, 2.54) and 1.65 (1.22, 2.24)] than HIV+/HCV- and HIV-/HCV-[1.41 (1.18, 1.67) and 1.44 (1.17, 1.75), respectively]. After additional adjustment for lifestyle and metabolic factors, HIV+/HCV+ remained associated with 36% (95% CI: 4, 80%) greater HOMA-IR relative to HIV-/HCV-, whereas HIV-/HCV+ and HIV+/HCV- had smaller differences. Adjustment for sCD163 substantially attenuated the difference between HIV+/HCV+ and HIV-/HCV-; adjustment for I-FABP, sCD14, and IL-6 had little effect. Higher sCD163 was independently associated with 19% (95% CI: 7, 33%), 26% (95% CI: 15, 39%), 25% (95% CI: 14, 37%), and 23% (95% CI: 11, 36%) greater HOMA-IR in HIV+/HCV+, HIV-/HCV+, HIV+/HCV-, and HIV-/HCV- (all estimates per doubling of sCD163). I-FABP, sCD14, and IL-6 were not associated with HOMA-IR.

CONCLUSION

HIV/HCV coinfection is associated with greater HOMA-IR, even after controlling for demographic, lifestyle, and metabolic factors. sCD163, which appears independent of intestinal epithelial damage and inflammation, partly explains this association. Our findings that the association of sCD163 with HOMA-IR occurred even in the absence of HIV and HCV, indicate that viral and nonviral factors affect sCD163 levels. Its role in insulin resistance needs elucidation.