Over 50's more likely to have elevated lipids and glucose during HIV therapy

Older HIV-positive patients are more likely than HIV-positive individuals under the age of 35 to experience increases in blood sugar, cholesterol and triglycerides after a year of antiretroviral therapy, Italian investigators report in the November edition of HIV Medicine. The study also revealed that older patients have a greater risk than younger patients of developing certain co-morbidities such as heart disease or diabetes after taking HIV treatment. However, the investigators found that anti-HIV therapy had a similar virological and immunological effect in older and younger patients.

With prompt diagnosis and appropriate treatment there is increasing optimism that HIV-positive individuals will survive into old age. The demographics of the HIV-positive population are already changing. In Italy in 1985, for example, the median age for male HIV-infected individuals was 29 and 24 for female patients. By 2004, these ages had increased to a median of 41 and 38 years.

Although older age has been associated with faster HIV disease progression and increased mortality, HIV treatment guidelines do not make any specific recommendations regarding the use of antiretrovirals in older patients.

Therefore, doctors in Milan conducted longitudinal analysis comparing treatment outcomes, the rate of metabolic complications, and the incidence of side-effects and new co-morbidities after the first year of HIV therapy in patients aged over 50 years and those aged between 25 and 35 years.

A total of 159 older patients and 118 controls were included in the investigators’ analysis. The older patients had a mean age of 59 years compared to 30 years in the younger patients.

Baseline characteristics

Significant baseline differences between the older and younger patients were identified by the investigators. Fewer than 1% of older patients were infected with HIV via injecting drug use, compared to 23% of the under-35s (p

Before starting HIV therapy, similar rates of co-morbidities were identified in the two groups of patients (59 older patients versus 52 younger patients). However, there were significant differences in the types of co-morbidities affecting the two groups of patients: older individuals tended to have cardiovascular diseases and diabetes, whereas younger patients had a higher prevalence of liver disease; this is consistent with the higher prevalence of injecting drug use as a risk factor for younger patients.

A total of 42 older patients, but just six of the under-35s (p

Immunological and virological effects of HIV therapy

In both older and younger patients the mean decrease in viral load after a year of HIV therapy was 2.6 log₁₀. A viral load below 500 copies/ml after a year’s therapy was achieved by identical proportions of both patient groups (78%).

Mean baseline CD4 cell count was 202 cells/mm³ for older patients and 188 cells/mm³ amongst younger patients. A year of HIV treatment yielded a mean increase to 367 cells/mm³ in older patients and 391 cells/mm³ in the younger, control group. This difference was not statistically significant.

Metabolic effects of anti-HIV therapy

Older patients were significantly more likely to experience increases in blood fats and sugars. Cholesterol levels above 6.47 mmol/l were observed in 18% of older patients compared to just 6% of younger patients (p

Liver toxicities

By contrast, younger patients were more likely to have blood test results suggesting that they were experiencing mild liver toxicities. Grade 1 elevations in ALTs were seen in 74 younger patients and 25 older patients, and grade 2 elevations in 22 under-35s and seven over-50s. However, more severe liver-related toxicities occurred with slightly increased frequency in older patients.

Side-effects

A similar instance of side-effects was seen in the over-50s (80 events) and the under-35s (61 events). The investigators noted, however, that older patients were more likely than younger individuals to experience bone-marrow side-effects (p = 0.009) and peripheral neuropathy (p = 0.02).

New co-morbidities

A total of 39 new co-morbidities were seen in older patients. New neuropsychiatric diagnoses accounted for 19 of these, with cardiovascular disease another ten and diseases such as diabetes ten more. In younger patients, three new neuropsychiatric diagnoses were made along with one new diagnosis of cardiovascular disease.

“Older HIV-infected persons…constitute, in our opinion, a subgroup of patients for whom specific considerations are critical for the appropriate selection and monitoring of safe and effective antiretroviral treatment”, write the investigators.