Swiss research shows that non-AIDS-related diseases are now
a major cause of illness in patients with HIV, and that the risk of such
diseases increases with age. The research, which is published in the online
edition of Clinical Infectious Diseases,
is accompanied by an editorial emphasising the increasing importance of
primary care in the management of patients with HIV.
As recently published studies have shown, improvements
in treatment and care have increased the life expectancy of many patients with
HIV. Nevertheless, these patients still have a higher burden of disease
than that observed in the general population, and are likely to develop to the
diseases of ageing earlier.
Investigators from the Swiss HIV Cohort Study wished to
establish the influence of ageing on the epidemiology of non-HIV-related
illnesses in their patients.
They therefore designed a study involving 8444 patients who
received care between 2008 and 2010. The incidence and risk of AIDS-related and
non-HIV-related illnesses was calculated and compared between patients in three
different age groups (under 50, 50 to 64, and above 65).
Overall, the patients had a median age of 45 years. Over
two-thirds (68%) were aged under 50, 26% were in the 50 to 64 age group, and 5%
were aged 65 or above. Between 1990 and 2010, the proportion of patients aged
between 50 and 64 increased from below 3% to over 25%. “If this trend continues
over the next decade,” writes the author of the accompanying editorial, “up to
50% of patients in [the Swiss] cohort will be > 50 years of age. Such an
outcome was unimaginable 30 years ago, when AIDS was first described.”
Most of the patients (71%) were male, 85% were taking
antiretroviral therapy, 81% had an undetectable viral load, and the current
median CD4 cell count being 528 cells/mm3. Approximately a third of
patients were taking medication for a condition other than HIV.
A total of 2% of patients died. The leading causes of death
were cancers, infections, and cardiovascular disease. There were 95 new AIDS
defining events, but the total number of non-HIV-related events was a
remarkable ten times higher.
The 994 non-AIDS-defining events included 201 cases of
bacterial pneumonia, 55 heart attacks, 39 strokes, 70 cases of diabetes, 123
trauma-related fractures, 37 fractures without trauma, and 115 non-AIDS-related
The mortality rate was 7.81 deaths per 1000 person years,
and there were 87.5 hospitalisations per 1000 person years. The incidence of
new AIDS-defining events was 4.32 cases per 1000 years, compared to an
incidence rate of 53.3 per 1000 person years for any clinical event.
Mortality and hospitalisation rates increased significantly
as the patients aged. The mortality rate was 5.92 per 1000 person years for
those aged under 50, increasing to 22.5 per 1000 person years for the over 65s (p <
Similarly rates of bacterial pneumonia (p = 0.005), stroke
(p < 0.001), heart attack (p < 0.001), fracture (p < 0.001),
osteoporosis (p < 0.001), diabetes (p < 0.001), and non-AIDS-defining
cancer (p < 0.001) all increased significantly as the patients aged.
The association between advancing age and an increased risk
of these illnesses remained robust after the investigators adjusted for CD4
cell count, viral load, and duration of HIV infection.
An increasing CD4 cell count reduced the risk of both HIV-related
and non-HIV-related illnesses (p < 0.001). A detectable viral load was
associated with an increased risk of bacterial pneumonia, HIV-related
progression, and some non-HIV-related events (p < 0.001). The risk of
AIDS-related and non-HIV-related events was also increased by lifestyle
factors, most notably injecting drug use and smoking.
“Non-AIDS comorbidities, particularly cardiovascular
disease, osteoporosis, diabetes mellitus, and non-AIDS-defining malignancies
become increasingly important in HIV-infected persons and increase with older
age,” conclude the investigators. “Because age is a nonmodifiable factor, it is
particularly important to carefully screen for and prevent age-related
modifiable risks of non-AIDS comorbidity.”
In his accompanying editorial, Dr Michael Saag suggests that
the best place for this screening to take place is primary care, noting
“primary care providers are very comfortable with management of and, in many
ways, are better equipped to manage the myriad of multiple comorbidities that
naturally occur in patients as they age.”