There is a high
prevalence and incidence of pre-cancerous cervical lesions in HIV-positive
South African women, investigators report in the online edition of AIDS.
“This is the most
comprehensive longitudinal report of cytological progression and regression of
a large number of HIV-infected women followed prospectively in a high HIV, high
HPV [human papillomavirus] setting,” comment the researchers.
They add, “over
one-quarter of women with a baseline normal or [low grade] lesions progressed
to high grade cervical lesions during follow-up.”
Antiretroviral treatment had a moderately protective effect against progression of lesions.
The authors believe
that their findings have implications for cervical screening strategies in
South Africa. However, they do not think that annual check-ups would be cost
effective. Instead, they recommend that the frequency of screening should be
determined by CD4 cell count.
Access to HIV therapy
in South Africa is increasing, therefore significantly extending the prognosis
of a large proportion of patients. Infection-related malignancies, such as
cervical cancer, are an increasingly important cause of illness and death in
patients with HIV.
Treatment for cervical
cancer is more likely to succeed if pre-cancerous cell changes are detected
early. Therefore investigators wished to establish the prevalence and progression
of cervical lesions among HIV-positive women in Soweto.
A total of 2325 women
had a cervical smear between 2003 and 2009. Only 4% were taking HIV treatment
at baseline, but a further 15% initiated therapy during follow-up. The women were followed for a median of
24 months.
At the time of the initial
screen, 38% of women had pre-cancerous lesions. Their average age was 32 and
their median CD4 cell count 254 cells/mm3, which was significantly
lower than the median of 351 cells/mm3 observed in women with normal
cervical cytology (p < 0.0001).
Each 100 cell/mm3
increase in CD4 cell count reduced the risk of low-grade lesions by 13%, and high-grade
lesions by 18%.
In addition, each five
year reduction in age reduced the risk of low-grade lesions was 10%.
A subsequent smear was
performed on 1193 women. Women who had only one smear were significantly more
likely to have abnormal lesions at baseline (p < 0.001). They were also more
likely to have been lost to follow-up or to have died (p < 0.001).
Overall, 11% of women
with a normal cytology or low-grade lesions at baseline developed high-grade
lesions. This provided an incidence of 9.6 per 100 person years.
Of the 832 women whose
first smear results were normal, 22% developed low-grade lesions and 1% high-grade
lesions.
However, an
improvement in cervical cytology was also observed in many women.
When the investigators
looked at the smear results of the 225 women with low grade lesions at baseline,
and who had a second smear at least 11.5 months later, they found that the
lesions had regressed in 44% of individuals.
Patients with a CD4
cell count below 200 cells/mm3
were almost twice as likely as those with a CD4 cell count above 500 cells/mm3
to experience disease progression (p < 0.0001).
Taking HIV treatment
reduced the risk of disease progression by 28%. (p < 0.05). “We were able to
show a protective effect of HAART [highly active antiretroviral therapy]
despite short durations of ART,” write the authors.
Only age above 45 was
associated with the regression of lesions. This finding surprised the
investigators, who commented: “low grade lesions in older women would be
expected to be more persistent lesions. The protective effect of age…is
unexplained.”
The researchers believe that their
findings have implications for cervical screening programmes in South Africa.
It is current practice to screen women every ten years, but the authors
recommend “shorter screening intervals” for women with a CD4 cell count below
500 cells/mm3.
However, they do not
believe that annual screening would be an efficient use of scare healthcare
resources, as many abnormalities are “transient” and destined to “resolve with
time”.
Instead they believe
that the screening interval should be determined by a patient’s CD4 cell count,
and that patients with weak immune systems should have the most frequent
monitoring.