Risk factors for cardiovascular disease are common amongst young, HIV-positive women in the US, investigators report in the January 1st edition of Clinical Infectious Diseases.
“More than one-third…reported a family history of heart disease or of type 2 diabetes, more than one-third smoked cigarettes, and fewer than one-third exercised regularly”, comment the investigators.
When added to the inflammation caused by HIV and the side-effects of antiretroviral therapy the researchers believe that “this population of young women may be at particularly high risk of cardiovascular disease and other adverse events.”
Over a third of new HIV infections in the US each year are among people aged below 30. The epidemic in the US disproportionately affects ethnic and racial minorities and obesity is increasing among younger people in these US populations.
As the inflammation caused by HIV, and the side-effects of some anti-HIV drugs, have been linked to an increased risk of cardiovascular diseases, the investigators wished to determine the prevalence of other risk factors for such illnesses in young, HIV-positive women.
A total of 173 individuals were recruited to the study between 2003 and 2005. All were aged between 14 and 24 years.
The study population included 61 HIV-negative women who were included as controls.
The HIV-positive women were categorised according to their antiretroviral treatment status: therapy with a protease inhibitor; therapy with a non-nucleoside reverse transcriptase inhibitor (NNRTI); therapy with neither of these classes of drug; or no HIV treatment.
Fasting blood samples were taken to monitor lipids, triglycerides, glucose and insulin. C-reactive protein levels, markers of inflammation that have been linked to an increased risk of cardiovascular illnesses, were also monitored.
The women also had their height measured and were weighed. This enabled the investigators to calculate body mass index (BMI). Other body measurements were also taken. DEXA scans were performed to calculate total body fat percentage.
Detailed individual and family medical histories were provided by all the women. Furthermore, they also completed food diaries and completed questionnaires that included questions about exercise, smoking, and drug and alcohol use.
Median age was 20 years. Significantly more HIV-infected than HIV-negative women were African Americans (77% vs 56%, p = 0.005).
Cigarette smoking was reported by 34% of women, with no difference according to HIV status. However, HIV-positive individuals were significantly more likely to report illicit drug use (59% vs 36%, p = 0.002). Furthermore, fewer HIV-positive women reported regular exercise (32% vs 53%, p = 0.005).
Many of the women reported family histories of risk factors for cardiovascular disease. A family history of type 2 diabetes was reported by 44% of women with HIV, a history of lipid disorders by 27%, and a history of coronary heart disease by 38%.
More than 40% of the women in each group had a BMI above 25 and were therefore classified as overweight or obese.
Body shape differed little between the HIV-positive and HIV-negative women.
The investigators suggest that this was because use of d4T (stavudine, Zerit), a drug particularly linked to body fat changes, was low amongst the HIV-infected women.
Although AZT, (zidovudine, Retrovir) was widely used, the overall duration of antiretroviral therapy was short (maximum, 3.9 years for those taking a protease inhibitor). Therefore, the changes in body shape that can develop as a consequence of therapy with this drug had not yet occurred.
Triglycerides were higher among the HIV-infected women compared to those who were HIV-negative.
HIV treatment status affected cholesterol levels. Those taking a protease inhibitor or an NNRTI had higher total cholesterol than both HIV-negative women and the HIV-infected women who were not yet taking HIV treatment.
Furthermore, HDL or 'good' cholesterol, was lower amongst the antiretroviral-naive women and those taking an NRTI only regimen than it was amongst the HIV-negative women.
Insulin and glucose levels were comparable between the HIV-positive and HIV-negative women.
However, the investigators found that levels of C-reactive protein were significantly higher amongst women with HIV (p = 0.006).
Moreover, 40% of women taking antiretroviral therapy had a C-reactive protein level above the upper limit of normal (3 mg/l).
“In summary, obesity, dyslipidemia, and inflammation were prominent findings in this group of behaviourally HIV-infected adolescent women”, comment the investigators.
The researchers suggest that several factors are likely to contribute to these findings: “In addition to HIV infection and antiretroviral therapy, our data illustrate the significant impact of overweight and obesity on dyslipidemia, insulin resistance and elevated C-reactive protein levels in this population.”
When coupled with high levels of smoking, a low prevalence of exercise, and family histories of diabetes, and heart disease, the investigators believe that “these factors may accelerate the lifetime risk of cardiovascular disease and other adverse events in a group that is facing lifelong exposure to antiretroviral therapy.”
Mulligan K et al. Obesity and dyslipidemia in behaviourally HIV-infected young women: Adolescents Trials Network Study 021. Clin Infect Dis 50: 106-14, 2010.