Higher levels of engagement in HIV care can reduce deaths among people with AIDS at all stages of infection, with or without antiretroviral therapy (ART), according to a new study. This association is largely explained by poorer CD4+ cell count profiles in those with suboptimal engagement in care.
“Among patients attending for care for at least a year, a combination of routinely collected clinical and laboratory data is able to identify, through engagement patterns, individuals at increased risk of subsequent mortality both before and after starting ART,” stated the researchers, led by Professor Caroline A. Sabin, of the University College London, in the UK.
The researchers published their results online on March 1, 2017 in AIDS.
The widespread use of ART has dramatically reduced morbidity and mortality among people with HIV. However, the health benefits can only be achieved if people know they are HIV positive and if they maintain sustained engagement with care.
Up to one-quarter of patients in outpatient HIV clinics do not attend regularly. The result can be poorer health outcomes, including failure to suppress HIV viremia, increased drug resistance, and suboptimal CD4+ cell count responses according to the researchers.
They identified 44,432 HIV-positive participants who made more than 1 visit after January 1, 2000 to many of the UK's largest HIV clinical centers. About one-quarter of the patients were women; half were homosexuals; and slightly more than one-quarter were black African. Median age was 36 years.
Each person-month was classified as in or out-of-care based on the dates of the expected and observed next care visits. The researchers investigated associations between mortality and the cumulative proportion of months spent in care, lagged by 1 year, and cumulative time spent in care before ART in those attending clinic for more than 1 year. Adjustments were made for age, CD4+/viral load, year, sex, infection mode, ethnicity, and receipt/type of ART.
Higher time spent in care was associated with lower mortality both before and after adjustments. Adjustments for future CD4+ changes revealed that the association was explained by poorer CD4+ cell counts in those with lower time spent in care.
A total of 8,730 participants who were followed for more than 1 year initiated ART; 237 patients (2.7%) died.
Those who spent more time in care before ART initiation had a reduced risk of death before and after adjustments. This association was again explained by poorer post-ART CD4+/ viral load in those with lower pre-ART time spent in care.
The authors wrote: “Our analyses benefit from a large, prospectively compiled, clinical data set with longitudinal data on CD4+ cell counts, viral loads, and ART use. By separating our assessment of engagement from clinical outcomes by 12 months, we were also able to reduce the impact of reverse causality, whereby individuals who are sicker may attend for care more frequently than those who are well.”
They recognized that their algorithm does not capture additional information that might modify a clinician's decision about the timing of the next visit, such as psychosocial factors.