Abstract Body

Extending appointment intervals for stable HIV-infected patients in sub-Saharan Africa can reduce opportunity costs to patients and decongest overcrowded facilities, but has not been prioritized as a strategy, with shorter intervals still being more common, in part due to concerns of waning engagement with longer absences.

As part of the Better Info study, we analyzed a cohort of stable HIV-infected adults (on treatment >6m, CD4 >200 cells/μl) who presented for a routine clinical visit from January 1, 2013 to July 31, 2015 in Zambia. We used missed visits (>14d late to next visit), gaps in medication (>14d late to next pharmacy refill), and loss to follow-up (LTFU, >90d late to next visit) as indicators of retention. We utilized multilevel logistic regression adjusting for patient characteristics-including an individual’s prior retention history-to assess the association between scheduled appointment intervals and subsequent lapses in retention.

127,448 patients (66% female, median age 39y [IQR 33-46], median CD4 444 cells/μl [IQR 325-595]) made 857,900 routine visits to 71 sites. Most visit intervals were 30d (25-45d, 43%), followed by 60d (46-75d, 21%), and 90d (76-105d, 33%); 3.3% were <25d and 0.9% were >105d. Patients given longer follow-up (>76d) were slightly more on time to current visit and had a history of slightly fewer missed visits and slightly higher medication possession ratio, but were of similar age and gender makeup. Longer visit intervals were associated with improved probability of making the next visit on time (Figure). After adjustment and as compared to patients scheduled for 30d follow-up, patients with longer appointment intervals were less likely to have subsequent lapses: 60d follow-up (late aOR 0.82, p<0.001; medication gap aOR 0.91, p<0.001; LTFU aOR 0.96, p<0.03), 90d follow-up (late aOR 0.56, medication gap aOR 0.69, LTFU aOR 0.94; p<0.001 for all), and >106d follow-up (late aOR 0.37, medication gap aOR 0.59, LTFU aOR 0.71; p<0.001 for all). Patients with very short follow-up (<25d) were more likely to have retention lapses (late aOR 1.89, medication gap aOR 1.56, LTFU aOR 1.29; p<0.001 for all).

Longer visit intervals are associated with decreased lateness, gaps in medication, and LTFU in stable HIV-infected patients even when adjusting for prior retention history. Extending visit intervals to 3 months, and potentially up to 6 months, may represent a promising strategy to reduce patient burden of care and decongest clinics.