30% decline in deaths after expansion of ART access in rural Kenya

Expansion of HIV programme services over a five year period in a high HIV prevalence area of rural Kenya resulted in close to a third of HIV-positive adults getting care and over 60% starting ART, coinciding with a 30% decline in overall adult death rates according to an analysis of health, demographic and mortality data published in the advance online edition of AIDS.

Death rates at the population level for AIDS and tuberculosis declined by 26% and 47% for other infectious diseases, but remained at the same level for non-infectious diseases. This would suggest an infectious disease intervention, note the authors.

Rapid scale-up of HIV services and the provision of ART in sub-Saharan Africa have resulted in improved health and fewer deaths. The effect at the individual level is well documented. A few studies in sub-Saharan Africa have shown that with the establishment of ART programmes population adult death rates have declined.  These studies have described patient characteristics at the time of enrolment and how they relate to access, retention and survival.

The authors suggest by looking at changes in demographics or clinical status of patients during scale-up may help gain a better understanding of the impact of HIV care and treatment at the population level in a defined geographical area.

With an HIV prevalence of 14.9%, the rural Nyanza Province in western Kenya is the highest in the country. Approximately 500,00 people are living with HIV/AIDS. High rates of malaria and tuberculosis are also prevalent.

In 2003 HIV care and ART services were established and expanded over a five-year period. Since 2001 a Health and Demographic Surveillance System  (HDSS) maintained by the Kenya Medical Research Institute in collaboration with the US Centers for Disease Control and Prevention have recorded population characteristics and death rates from approximately 140,000 residents within Nyanza Province.

The authors linked adult HDSS HIV clinical records to population level HDSS demographic and mortality data to describe uptake of HIV care and ART and its effect upon changes in adult death rates in a time of rapid expansion of HIV services in Nyanza Province.

They also chose to describe changes in (socio-demographic) enrolment and clinical characteristics among patients (pre-ART and ART) during this time and so identify trends. The authors believe this to be the first time this has been explored.

In 2003 11 DHSS residents were documented as enrolled in HIV care at one health facility. The numbers rapidly increased. From 2003 to 2008 a total of 5421 HDSS residents had enrolled in HIV care. 3331 (61.4%) were linked to HDSS follow-up data. Health facilities had increased to 17 of which 70% (12) offered ART. HIV positive residents getting HIV services rose from under 1% to close to 30%. ART coverage (CD4 cell counts under 250 cells/mm³) rose from less than 1% from 2003 to 2005 to 6.6% in 2006 to 64% in 2008.

The proportion of those being referred from voluntary counselling and testing sites decreased while other clinic-based referrals increased. Six percent were referred from prevention of mother to child transmission (PMTCT) programmes and antenatal clinics (ANC).

Median distance from the residence to the clinic decreased over time (4.4 km IQR: 2.4-8.1 km to 3. 2 km,IQR: 2.2-5.7 km, p <000.1). The proportion of those with WHO clinical stage 4 at enrolment fell from 20.4% to 1.9% while CD4 testing at enrolment increased from 1% to 53.4%, p<000.1.  

Decentralisation of services enabled patients to access care closer to home. As expansion of services increased so did system efficiencies resulting in better quality of care. CD4 testing became available and reduced time to start of ART. So patients presented earlier in the course of their illness.

The proportion of patients in HV care with a primary education or less and those with home access to safe water increased significantly, 71.9 to 79.3, p=0.01 and 18.1 to 31.2, p<0.0001, respectively.

Most patients (92.9%) were getting cotrimoxazole (CTX) prophylaxis.

ART has been shown to reduce the risks of transmission. In addition, other components of HIV care (CTX prophylaxis, better access to safe water compared to the general population in this study, TB screening) while reducing the risks of death and disease in the individual might also have benefitted the family and community. So the overall effect at the population level would be greater than the sum of individual HIV care.

Adult death rates dropped by a third during this time of rapid scale-up.

The researchers note while there is no direct relationship between expansion of HIV services and population decline in death rates it is the most likely reason.

Health interventions in place at the time were focussed on pregnant women (malaria prevention initiatives) and reducing under five death rates. No other significant health interventions were in place.

The greatest decrease in death rates was among those age groups with the highest HIV prevalence. Deaths from non-infectious diseases did not decrease implying an infectious disease intervention, the researchers add. In addition, these findings are consistent with other studies in high prevalence areas of sub-Saharan Africa where AIDS-related death rates dropped considerably following widespread ART provision.

A key strength of the study is the linkage between clinic data and population surveillance allowing the authors to look at declining death rates at the patient and population level.

While PMTCT services grew during this time referral was low (5.1%) and very few women (25) reported PMTCT ARV prophylaxis. Even though clinical status at enrolment improved from a median of 192 (IQR: 111-279) cells/mm³ in 2005 to 256 (IQR: 130-457) cells/mm³ in 2008 (p=0.007), it was still low with 44% qualifying for ART at enrolment.

The authors conclude “efforts to identify HIV-positive individuals earlier and achieve rapid enrolment into clinical care with high rates of retention and ART adherence are warranted to optimise individual and population-level benefits of HIV care and ART services.”