Current ideas about HIV prevention include a mixture of primarily biomedical interventions, socio-mechanical interventions such as sterile syringe and condom distribution, and behavioral interventions. This article presents a framework for socially-integrated transdisciplinary HIV prevention that may improve current prevention efforts. It first describes one socially-integrated transdisciplinary intervention project, the Transmission Reduction Intervention Project. We focus on how social aspects of the intervention integrate its component parts across disciplines and processes at different levels of analysis. We then present socially-integrated perspectives about how to improve combination antiretroviral treatment (cART) processes at the population level in order to solve the problems of the treatment cascade and make treatment as prevention more effective. Finally, we discuss some remaining problems and issues in such a social transdisciplinary intervention in the hope that other researchers and public health agents will develop additional socially-integrated interventions for HIV and other diseases.

We explored the relationship between vitamin D levels and insulin resistance (IR) among 1082 nondiabetic (754 HIV-infected) women enrolled in the Women's Interagency HIV study (WIHS), a large and well-established cohort of HIV infected and uninfected women in the US. Vitamin D levels 20-29 ng/mL were considered insufficient and <20 ng/mL deficient. IR was estimated using the homeostasis model assessment (HOMA) and a clinically significant cut-off ≥2.6 was used for HOMA-IR. In the unadjusted analysis, women who were vitamin D insufficient or deficient were 1.62 (95% CI: 1.01-2.61, p=0.05) and 1.70 (95% CI: 1.11-2.60, p=0.02) times more likely to have HOMA values≥2.6 compared to women with sufficient vitamin D. The association did not remain significant after adjustment for factors associated with IR. Among the 754 HIV-infected women, current PI use (OR 1.61, 95% CI: 1.13-2.28, p=0.008) remained independently associated with HOMA ≥2.6 while vitamin D insufficiency (OR 1.80, 95% CI: 0.99-3.27, p=0.05) was marginally associated with HOMA ≥2.6 after adjustment. Ethnicity, body mass index, smoking status, and hepatitis C status were independently associated with insulin resistance in HIV-infected and uninfected women. We found a marginally significant association between vitamin D insufficiency and insulin resistance among nondiabetic HIV-infected WIHS women.

Background

Recent studies in HIV-infected men report an association between low vitamin D (25OH-D) and CD4 recovery on HAART. We sought to test this relationship in the Women's Interagency HIV Study (WIHS).

Methods

We examined 204 HIV-infected women with advanced disease, who started HAART after enrollment in the WIHS. We measured vitamin D (25OH-D) levels about 6 months prior to HAART initiation. The relationship between CD4 recovery (defined as increases of ≥50, 100, and 200 cells at 6, 12, and 24 months) and exposure variables was examined using logistic regression models at 6, 12 and 24 months post-HAART initiation in unadjusted and adjusted analyses, and using multivariable longitudinal Generalized Estimating Equations (GEE). Vitamin D insufficiency was defined as 25OH-D levels at least 30 ng/ml.

Results

The majority were non-Hispanic black (60%) and had insufficient vitamin D levels (89%). In adjusted analyses, at 24 months after HAART, insufficient vitamin D level (OR 0.20, 95% CI 0.05-0.83) was associated with decreased odds of CD4 recovery. The undetectable viral load (OR 11.38, 95% CI 4.31-30.05) was associated with CD4 recovery. The multivariable GEE model found that average immune reconstitution attenuated significantly (P < 0.01) over time among those with insufficient vitamin D levels compared with those with sufficient vitamin D levels.

Conclusion

Vitamin D insufficiency is associated with diminished late CD4 recovery after HAART initiation among US women living with advanced HIV. The mechanism of this association on late CD4 recovery may be late vitamin D-associated production of naive CD4 cells during immune reconstitution.