Retention on antiretroviral therapy at 12 months

Export Indicator

Percentage of adults and children living with HIV known to be on antiretroviral therapy 12 months after starting
What it measures

Progress in increasing survival among adults and children living with HIV by maintaining them on antiretroviral therapy.

Rationale
One goal of any antiretroviral therapy programme is to increase survival among people living with HIV. As antiretroviral therapy is scaled up around the world, understanding why people drop out of treatment programmes and how many do this is important. The data can be used to demonstrate the effectiveness of programmes and highlight obstacles to expanding and improving them.
Numerator

Number of adults and children who are still alive and receiving antiretroviral therapy 12 months after initiating treatment in 2016

Denominator
Total number of adults and children initiating antiretroviral therapy in 2016, within the reporting period, including those who have died since starting antiretroviral therapy, those who have stopped treatment and those recorded as lost to follow-up at month 12
Calculation

Numerator/denominator

Method of measurement
Programme monitoring tools; cohort and group analysis forms
 
Antiretroviral therapy registries and antiretroviral therapy cohort analysis report form.
 
The reporting period is defined as any continuous 12-month period that has ended within a predefined number of months from the submission of the report. National reporting requirements can determine the predefined number of months. If the reporting period is 1 January to 31 December 2017, countries will calculate this indicator by using everyone who started antiretroviral therapy any time between 1 January and 31 December 2016.
 
 
Measurement frequency
As people start antiretroviral therapy, monthly cohort data should be collected continuously. Data for monthly cohorts completing at least 12 months of treatment should then be aggregated.
Disaggregation
  • 0-14 years for children and 15 years and older by sex (men and women) for adults
  • Breastfeeding status when starting therapy
Additional information requested
Provide city-specific data for this indicator. Space has been created in the data entry sheet to provide information for the capital city as well as one or two other key cities of high epidemiological relevance: for example, those that have the highest HIV burden or have committed to ending AIDS by 2030.
Explanation of the numerator

The numerator is defined as the number of adults and children alive and receiving antiretroviral therapy 12 months after starting treatment. For a comprehensive understanding of survival, the following data must be collected:

  • The number of adults and children in the antiretroviral therapy start-up groups starting antiretroviral therapy at least 12 months before the end ofthe reporting period.
  • The number of adults and children still alive and on antiretroviral therapy at 12 months after initiating treatment.
 
The numerator does not require people to have been receiving antiretroviral therapy continuously for the 12-month period. People who missed one or two appointments or drug pick-ups and temporarily stopped treatment during the 12 months but are recorded as still receiving treatment at month 12 are included in the numerator. In contrast, people who have died, stopped treatment or been lost to follow-up at 12 months since starting treatment are not included.
 
For example, for people who started antiretroviral therapy in May 2016: if at any point between May 2016 and May 2017 they die, are lost to follow-up (and do not return) or stop treatment (and do not restart), then at month 12 (May 2017) they are not on antiretroviral therapy and not included. However, a person who started antiretroviral therapy in May 2016 and who missed an appointment in June 2016 but is recorded as on antiretroviral therapy in May 2017 (at month 12) should be included in the numerator. What is important is that the person who started antiretroviral therapy in May 2016 is recorded as being alive and receiving antiretroviral therapy after 12 months, regardless of what happens from May 2016 to May 2017.
 
Antiretroviral therapy registries should include a number of variables describing people, such as their age when they start treatment. In addition, many registries will include information indicating whether the person was breastfeeding when starting treatment. Retention for these subsets should be reported as of the starting date.

 

Explanation of the denominator

The denominator is the total number of adults and children in the antiretroviral therapy start-up groups who initiated antiretroviral therapy at any point during the 12 months before the beginning of the reporting period, regardless of whether they are still alive or have been lost, stopped therapy or died..

For example, the reporting period 1 January to 31 December 2017 will include everyone who started antiretroviral therapy during the 12-month period from 1 January to 31 December 2016. This includes everyone receiving antiretroviral therapy as well as those who died, stopped treatment or are lost to follow-up at month 12.

At the facility level, the number of adults and children receiving antiretroviral therapy at 12 months includes people transferring in at any point from the start of treatment to the end of the 12-month period and excludes people who have transferred out during this same period to reflect the net current cohort at each facility. In other words, at the facility level, people who have transferred out will not be counted in either the numerator or the denominator. Similarly, people who have transferred in will be counted in both the numerator and denominator. At the national level, the number of transferred-in people should match the number of transferred-out people. The net current cohort (people whose outcomes the facility is currently responsible for recording; that is, the number of people in the start-up group plus any transfers in and minus any transfers out) at 12 months should therefore equal the number in the start-up cohort group 12 months before.

Strengths and weaknesses

This denominator may underestimate true survival, since some of the people lost to follow-up are alive. The number of people alive and on antiretroviral therapy (retention on antiretroviral therapy) in a treatment cohort is captured here.

Priority reporting is for aggregate survival reporting at 12months. If comprehensive cohort patient registries are available, then countries are encouraged to track retention on treatment at 24, 36 and 48 months and yearly thereafter. This will enable the comparison over time of survival on antiretroviral therapy. As it stands, identifying whether survival at 12 months increases or decreases over time is possible. However, cause cannot be attributed to these changes. For example, if survival at 12 months increases over time, this may reflect an improvement in care and treatment practices or earlier initiation of antiretroviral therapy. Retention at 12 months needs to be interpreted in relation to the baseline characteristics of the cohort when antiretroviral therapy started; mortality will be higher at sites at which people accessed antiretroviral therapy at a later stage of infection. Collecting and reporting data on survival over longer durations of treatment outcomes may therefore provide a better picture of the long-term effectiveness of antiretroviral therapy.

Further information

WHO guidance on treatment and care (http://www.who.int/hiv/topics/treatment/en/index.html).