CD4/CD8 ratio may predict risk of Kaposi sarcoma, NHL in HIV patients
Restoration of CD4/CD8 ratio on combination antiretroviral therapy (cART) was associated with decreased risk of Kaposi sarcoma (KS) while baseline CD8 count was related to non-Hogkin lymphoma (NHL) risk in people living with HIV (PLHIV) who had achieved viral suppression on cART, according to the COHERE* study presented at the AIDS International Conference (AIC) 2018.
“A persistently abnormal CD4/CD8 ratio despite cART reflects ongoing immune dysfunction and has been inversely correlated with the risk of non-AIDS defining cancer in PLHIV,” said Dr Sophie Grabar of Institut Pierre Louis d'Épidémiologie et de Santé Publique in Paris, France.
The COHERE study involved 58,308 patients (median age, 38 years, 76 percent men) who had achieved virological control (defined as viral load ≤500 copies/mL) by 9 months following cART initiation. The first CD4/CD8 measurement with virological control (given that viraemia suppression was persistent subsequently) was taken as the baseline. The participants were followed over a median duration of 59 months. [IAC 2018, abstract TUPEC265]
Overall, 221 cases of KS and 187 cases of NHL were diagnosed after 9 and 18 months, respectively from baseline. Restoration of CD4/CD8 ratio (≥1) was achieved in 28 percent (95 percent confidence interval [CI], 27–28) of participants at 2 years.
PLHIV who achieved CD4/CD8 ratio restoration, along with CD4 restoration (≥350/mm3), had a 32 percent lower risk of Kaposi sarcoma (adjusted hazard ratio [HR]; p=0.0006) compared with those who failed to restore CD4/CD8 ratio (although CD4 was restored).
The finding remained after adjusting for baseline patient characteristics such as sex, age, geographical origin, cART initiation, HIV transmission, and time-dependent variable such as virological failure (viral load >500 copies/mL).
On the other hand, high baseline CD8 count (≥2,000/mm3) was associated with an almost twofold increase in NHL risk (HR, 1.92; p=0.0156) compared with reference (<1,000/mm3 CD8 count).
“In this population of patients who had achieved suppressed viraemia, restoration of the CD4/CD8 ratio may confer an additional benefit to CD4 restoration with regard to KS risk. For NHL risk, the main immunological associated factor was baseline CD8 count,” summarized Grabar.
“A closer clinical monitoring should be proposed in patients with high CD8 count despite virological control and/or low persistent CD4/CD8 ratio,” she added.
For both KS and NHL, the risks were more than doubled in case of virological failure (HRs, 2.71 and 2.34 for KS and NHL, respectively; p<0.0001 for both).
“Avoiding virological failure appeared to be key to minimize KS and NHL risks,” highlighted Grabar.