Trends in loss to follow-up among migrant workers on antiretroviral therapy in a community cohort in Lesotho.
BACKGROUND
The provision of antiretroviral therapy (ART) to migrant populations raises particular challenges with respect to ensuring adequate treatment support, adherence, and retention in care. We assessed rates of loss to follow-up for migrant workers compared with non-migrant workers in a routine treatment programme in Morjia, Lesotho.


METHODS
All adult patients (≥18 years) initiating ART between January 1, 2008, and December 31, 2008, and followed up until the end of 2009, were included in the study. We described rates of loss to follow-up according to migrant status by Kaplan-Meier estimates, and used Poisson regression to model associations between migrant status and loss to follow-up controlling for potential confounders identified a priori.


RESULTS
Our cohort comprised 1185 people, among whom 12% (148) were migrant workers. Among the migrant workers, median age was 36.1 (29.6-45.9) and the majority (55%) were male. We found no statistically significant differences between baseline characteristics and migrant status. Rates of lost to follow up were similar between migrants and non-migrants in the first 3 months but differences increased thereafter. Between 3 and 6 months after initiating antiretroviral therapy, migrants had a 2.78-fold increased rate of defaulting (95%CI 1.15-6.73); between 6 and 12 months the rate was 2.36 times greater (95%CI 1.18-4.73), whereas after 1 year the rate was 6.69 times greater (95%CI 3.18-14.09).


CONCLUSIONS
Our study highlights the need for programme implementers to take into account the specific challenges that may influence continuity of antiretroviral treatment and care for migrant populations.
Médecins Sans Frontières, Morija, Lesotho. helenbygrave@hotmail.com
Helen
H
Bygrave
Katharina
K
Kranzer
Katherine
K
Hilderbrand
Jonathan
J
Whittall
Guillaume
G
Jouquet
Eric
E
Goemaere
Nathalie
N
Vlahakis
Laura
L
Triviño
Lipontso
L
Makakole
Nathan
N
Ford
D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000453:epidemiology; D006801:Humans; D007927:Lesotho / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D014171:Transients and Migrants
D019380:Anti-HIV Agents