Table 2.
Univariable and multivariable analysis of predictors of switching to second-line antiretroviral therapy.
| Univariable Analysis | Multivariable Analysis | |||
|---|---|---|---|---|
| HR (95% CI) | P | aHR (95% CI) | P | |
| Monitoring Strategy | <0·0001 | <0·0001 | ||
| Clinical | 0·51 (0·45–0·58) | 0·49 (0·43–0·56) | ||
| CD4 cell count | 1·00 | 1·00 | ||
| Targeted viral load | 1·55 (1·46–1·64) | 1·21 (1·13–1·30) | ||
| Routine viral load | 3·29 (3·10–3·49) | 3·15 (2·92–3·40) | ||
| Age at ART start | <0·0001 | <0·0001 | ||
| >30 years | 1·00 | 1·00 | ||
| ≤30 years | 1·30 (1·25–1·36) | 1·30 (1·25–1·36) | ||
| CD4 at ART start | <0·0001 | <0·0001 | ||
| ≥350 | 1·00 | 1·00 | ||
| 250–349 | 0·68 (0·60–0·76) | 0·77 (0·69–0·87) | ||
| 100–249 | 0·75 (0·69–0·82) | 0·78 (0·72–0·85) | ||
| 50–99 | 1·00 (0·92–1·09) | 1·07 (0·98–1·17) | ||
| <50 | 1·57 (1·44–1·72) | 1·55 (1·43–1·69) | ||
| Rural/Urban | <0·0001 | <0·0001 | ||
| Rural | 1·00 | 1·00 | ||
| Urban | 2·89 (2·70–3·10) | 1·50 (1·37–1·64) | ||
| Gender | 0·0126 | 0·0020 | ||
| Female | 1·00 | 1·00 | ||
| Male | 1·05 (1·01–1·09) | 1·07 (1·02–1·11) | ||
| Type of clinic | <0·0001 | <0·0001 | ||
| Health Center | 1·00 | 1·00 | ||
| District Hospital | 1·11 (1·06–1·16) | 1·11 (1·05–1·17) | ||
| Regional/University Hospital | 0·96 (0·92–1·01) | 1·14 (1·08–1·21) | ||
| WHO stage at ART start | <0·0001 | 0·0013 | ||
| 1 | 1·00 | 1·00 | ||
| 2 | 0·74 (0·69–0·79) | 0·98 (0·92–1·05) | ||
| 3 | 0·84 (0·79–0·89) | 1·02 (0·96–1·09) | ||
| 4 | 1·12 (1·04–1·21) | 1·14 (1·06–1·23) | ||
| Year of ART initiation | 0·2233 | |||
| 2004–2007 | 1·00 | <0·0001 | 1·00 | |
| 2008–2010 | 0·90 (0·86–0·94) | 0·96 (0·92–1·01) | ||
| 2011–2013 | 1·09 (0·96–1·22) | 1·02 (0·91–1·15) | ||
Results from Cox models stratified by IeDEA region. The multivariable analysis was adjusted for all variables in the table. Missing CD4 cell counts or WHO clinical stages were imputed.
Routine VL monitoring was assumed if at least 75 VL tests had been done per 100 person-years. CD4 monitoring was assumed if at least 75 CD4 counts had been done per 100 person-years. Targeted VL monitoring was assumed if in addition to CD4 monitoring at least 5 but less than 75 VL measurements were done per 100 person-years. A site was considered to use clinical monitoring if it did not meet the criteria for any other monitoring strategy.
ART: Antiretroviral therapy; CI: Confidence Interval; HR: Hazards Ratio