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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