A US study published in the June 11th edition of the Journal of the American Medical Association suggests that the increases in cholesterol levels seen in HAART-treated patients represent a normalisation of total and LDL cholesterol levels rather than a harmful consequence of therapy.
The study involved 50 of over 500 gay or bisexual HIV seroconverters enrolled in the Multicenter AIDS Cohort Study who had stored serum samples at six set points. These were pre-HIV seroconversion (between 1984 and 1995), after HIV seroconversion but before treatment with HAART was started (1990 to 1997), two samples during treatment with HAART between 1997 and 1999, and finally two serum samples obtained between 2000 and 2002.
Investigators wished to see how cholesterol levels fluctuated between these samples, which were collected over an average time period of twelve years.
At the pre-seroconversion visit the men had cholesterol levels comparable with those of healthy adult US males with total cholesterol an average 203mg/dL, HDL-cholesterol 52mg/dL and LDL cholesterol 121mg/dL.
However, notable declines in cholesterol levels were observed after the men became infected with HIV. The patient’s last pre-HAART serum sample showed that total cholesterol had fallen to by an average of 30mg/dL, HDL cholesterol by 12mg/dL and LDL cholesterol by 22mg/dL. Antiretroviral therapy had been provided to 90% of men in the study by this time.
All but two patients started a protease inhibitor-based HAART regimen, and by the time the third HAART serum sample was collected, total cholesterol had increased by 20mg/dL (95% CI –1 to 41) from pre-seroconversion levels, although HDL cholesterol was still 9mg/dL below the baseline level and LDL cholesterol 1mg/dL below baseline. Because four men started lipid-lowering medication before the fourth and final measurement the third sample was used for comparison.
The 39 smokers in the study had comparable lipid levels to the non-smokers. However, the investigators did find that the ten patients taking ritonavir-containing HAART regimens had larger increases from baseline in total cholesterol (60mg/dL) and LDL cholesterol (21mg/dL) than the other 40 men. However, the small number of patients prevented the investigators conducting comparisons.
An adherence level of at least 95% was achieved by 71% of patients at the time of the third post-HAART visit, when a fasting serum sample was obtained to measure triglycerides. The average triglyceride level was 225mg/dL, well above the 118mg/dL average for US adult men.
However, the investigators note that the 20mg/dL post-HAART increase in total cholesterol observed in their study “was consistent with expected change associated with age” and that LDL cholesterol was essentially unchanged from pre-seroconversion levels by the time of the third HAART sample.
”No prior study has reported changes in serum cholesterol values from pre-seroconversion values”, note the investigators, and that studies which have found apparent increases in cholesterol values by comparing pre and post-HAART levels have been insufficient as total and LDL cholesterol levels “tend to decrease substantially early after HIV infection.”
The investigators caution that their study sample was small and that serum samples were obtained without regard to fasting.
However, the investigators suggest that the observed increase in total and LDL cholesterol seen in their study may “represent a return to pre-seroconversion levels” and emphasises “the vital importance of comparing post-HAART lipid levels to pre-seroconversion levels whenever possible.”
Further information on this website
Cholesterol - factsheet
Nutrition - booklet in the information for HIV-positive people series
Diet changes successfully reduce cholesterol in HAART-treated patients - news story, June 2003
High levels of HDL cholesterol associated with longer undetectable viral load in HAART patients - news story, May 2003
Lipodystrophy - comprehensive menu of resources
Riddler SA et al. Impact of HIV infection and HAART on serum lipids in men JAMA 289: 2978 – 2982, 2003.