Do dyslipidemia, insulin resistance, and body shape changes differ according to race or ethnicity?

Data presented by Carl Grunfeld of UCSF from the CPCRA FIRST study extend existing data on the effects of race/ethnicity on metabolic and body composition variables in subjects initiating ART. This was a large (400 subjects) multi-ethnic (61% African-American, 28% white, 11% Latino) cohort that is noteworthy because it examined changes over time in these parameters. Only 22% of subjects were women however, including only 8 Latinas and 3 whites, which severely limits the studys ability to address any race-gender interaction.

Lipid levels in the general population differ across racial ethnic groups, and similar findings have been published in HIV-infected subjects on ART from cross-sectional studies (PLoS Medicine 2006).

Latinos tended to have the most adverse changes in lipid levels, while African-Americans had the least – in spite of the fact that African-Americans were more likely to receive a ritonavir-boosted PI. Fasting glucose levels and insulin resistance by HOMA-IR worsened in African-Americans and particularly among Latinos, but not in whites, which is consistent with the observation in the general population that non-white race increases the risk of diabetes mellitus.

At baseline, there was more waist subcutaneous area (representing primarily fat) in Latinos, whilst there was evidence for more non-subcutaneous area (representing primarily muscle) among African-Americans. There were no differences over time in thigh SQ area (ie fat) or thigh non-SQ area (ie muscle) between groups, but arm SQ area decreased more in Latinos – consistent with a greater tendency to develop lipoatrophy over time. Waist SQ area also decreased among Latinos but increased slightly in whites and African-Americans, also consistent with a greater tendency to experience SQ fat loss.

So what are the clinical implications of these data? Perhaps we can worry less about our African-American patients when it comes to lipid changes on ART, but lipid levels should still be obtained in all patients on ART regardless. Perhaps we should worry more about our African-American and Latino patients with regards to developing diabetes mellitus, but we should already be doing that based on long-known data in the general population.

Finally, perhaps we should worry more about lipoatrophy in Latinos, but vigilance for this side effect should be in place regardless of race/ethnicity. There is probably insufficient reason to prefer one class of antiretrovirals, or certain antiretrovirals within a class, for any particular racial/ethnic group based on these results.

Grunfeld C et al. Racial differences in long-term changes in metabolic parameters in antiretroviral-naive persons initiating HAART and Racial differences in long-term changes in body composition in antiretroviral-naive persons initiating HAART