Table 3. Cox regression univariate and multivariate models estimating risk of severe neutropenia within two years after ART initiation.
IeDEA West Africa collaboration, 2002–2014 (N = 9,426).
| Characteristic | Univariate analysis | Multivariate analysis1 | ||||
|---|---|---|---|---|---|---|
| HR | 95% CI | p | aHR | 95% CI | p | |
| Time-updated exposure to ZDV (months) | <10−4 | <10−4 | ||||
| 0 (Not exposed) | 1 | Ref. | 1 | Ref. | ||
| ]0–6] | 1.80 | 1.52–2.14 | 2.15 | 1.81–2.56 | ||
| ]6–12] | 1.81 | 1.39–2.35 | 2.09 | 1.60–2.72 | ||
| >12 | 1.37 | 1.01–1.86 | 1.62 | 1.18–2.22 | ||
| Calendar year for ART initiation | <10−4 | <10−4 | ||||
| 2002–2005 | 1 | Ref. | 1 | Ref. | ||
| 2006–2008 | 0.56 | 0.47–0.66 | 0.87 | 0.71–1.06 | ||
| 2009–2011 | 0.49 | 0.41–0.59 | 0.73 | 0.60–0.91 | ||
| 2012–2014 | 0.56 | 0.46–0.67 | 0.55 | 0.44–0.69 | ||
| Baseline neutrophils count (cells/mm3) | <10−4 | <10−4 | ||||
| ≥1,300 | 1 | Ref. | 1 | Ref. | ||
| 1,000–1,300 | 1.72 | 1.44–2.06 | 1.52 | 1.27–1.82 | ||
| 750–1,000 | 2.74 | 2.20–3.40 | 2.47 | 1.99–3.07 | ||
| Baseline hemoglobin level (g/dL) | 0.86 | 0.25 | ||||
| ≥10 | 1 | Ref. | 1 | Ref. | ||
| <10 | 1.03 | 0.89–1.19 | 1.13 | 0.97–1.32 | ||
| Missing | 1.07 | 0.78–1.47 | 0.90 | 0.55–1.47 | ||
| Clinical stage (CDC 3 or WHO 4) at initiation | <10−4 | <0.01 | ||||
| No | 1 | Ref. | 1 | Ref. | ||
| Yes | 1.39 | 1.17–1.64 | 1.21 | 1.02–1.44 | ||
| Missing | 1.04 | 0.88–1.24 | 1.59 | 1.08–2.34 | ||
| Time-updated CD4 count (cells/mm3) | <10−4 | <0.01 | ||||
| ≥350 | 1 | Ref. | 1 | Ref. | ||
| <350 | 1.41 | 1.19–1.66 | 1.26 | 1.07–1.49 | ||
| Missing | 1.11 | 0.85–1.46 | 1.57 | 1.11–2.22 | ||
1Analyses were stratified on HIV clinics.
HR, hazard ratio; aHR, adjusted hazard ratio; CI, confidence interval; ZDV, zidovudine; CDC, US Centers for Disease Control; WHO, World Health Organization.