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Table 2 Risk factors for reinfection: analysis adjusted for EIR only. Data from 2130 individuals in the AS-AQ trial arms and 2090 in the AL trial arms were analyzed using accelerated failure-time analysis. Regression coefficients are the ratio of time to reinfection, such that a coefficient > 1 indicates a longer time to reinfection. All results are adjusted for log EIR. Site-level random effects were included unless otherwise indicated. Models assume a lognormal time to reinfection

From: The duration of chemoprophylaxis against malaria after treatment with artesunate-amodiaquine and artemether-lumefantrine and the effects of pfmdr1 86Y and pfcrt 76T: a meta-analysis of individual patient data

Covariate (unit) Analysis adjusted for EIR only
N Coefficient [ratio of reinfection times] (95% CI) p value
Loge EIR (annual bites per person) 4220 0.79 (0.74, 0.85) < 0.001
AL 2090 1 (ref)  
 AS-AQ (overall) 2130 1.09 (1.05, 1.13) < 0.001
 AS-AQ (20% 86Y)* 1934 1.37 (1.28, 1.47) < 0.001
 AS-AQ (80% 86Y)* 1934 0.89 (0.84, 0.94) < 0.001
Age (polynomial, years, > 20 grouped together) 4213   < 0.001
 age   0.94 (0.90, 0.98)  
 (age)2   1.01 (1.00, 1.02)  
 (age)3   0.9998 (0.9994, 1.0001)  
Male gender 3861 0.98 (0.95, 1.02) 0.438
Anemic (hb < 10 g/dl) 3747 0.98 (0.93, 1.02) 0.277
Enlarged spleen (yes/no) 1390 1.00 (0.87, 1.15) 0.999
Presence of fever (> 37.5 °C) 4220 0.97 (0.93, 1.01) 0.146
Underweight (weight-for-age Z score < −2) 3193 0.98 (0.93, 1.04) 0.613
AQ dose (per 10 mg per kg increase) (AS-AQ arms only) 1839 1.00 (0.95, 1.06) 0.880
Lumefantrine dose (per 10 mg per kg increase) (AL arms only) 1850 1.02 (1.00, 1.04) 0.015
AS-AQ formulation
 FDC 1521 1 (ref)  
 Loose NFDC 373 0.83 (0.59, 1.18) 0.295
 Coblistered NFDC (AS-AQ arms only) 233 1.06 (0.68, 1.64) 0.803
pfmdr1 86Y prevalence (per 10% increase)
 AL arm 1891 1.03 (0.99, 1.07) 0.091
 AS-AQ arm 1934 0.96 (0.94, 0.98) < 0.001
pfcrt 76T prevalence (per 10% increase)
 AL arm 1964 1.03 (1.00, 1.07) 0.037
 AS-AQ arm 2001 0.97 (0.95, 1.00) 0.052
  1. *In a model including log10 EIR, drug, pfmdr1 86Y prevalence (per 10% increase) and interaction between drug and pfmdr1 86Y prevalence
  2. Site-level random effects not included because many sites did not measure this covariate
  3. p value interaction between drug and pfmdr1 86Y vs N86 prevalence < 0.001, p value interaction between drug and pfcrt 76T vs K76 prevalence < 0.001