title: Different factors associated with loss to follow-up of infants born to HIV-infected or uninfected mothers: observations from the ANRS 12140-PEDIACAM study in Cameroon.
abstract: BACKGROUND
  Loss to follow-up (LTFU) is a cause of potential bias in clinical studies. Differing LTFU between study groups may affect internal validity and generalizability of the results. Understanding reasons for LTFU could help improve follow-up in clinical studies and thereby contribute to goals for prevention, treatment, or research being achieved. We explored factors associated with LTFU of mother-child pairs after inclusion in the ANRS 12140-Pediacam study.
  
  
  METHODS
  From November 2007 to October 2010, 4104 infants including 2053 born to HIV-infected mothers and 2051 born to HIV-uninfected mothers matched individually on gender and study site were enrolled during the first week of life in three referral hospitals in Cameroon and scheduled for visits at 6, 10 and 14 weeks of age. Visits were designated 1, 2 and 3, in chronological order, irrespective of the child's age at the time of the visit. Mother-child pairs were considered lost to follow-up if they never returned for a clinical visit within the first six months after inclusion. Uni- and multivariable logistic regression were adjusted on matching variables to identify factors associated with LTFU according to maternal HIV status.
  
  
  RESULTS
  LTFU among HIV-unexposed infants was four times higher than among HIV-exposed infants (36.7% vs 9.8%, p < 0.001). Emergency caesarean section (adjusted Odds Ratio (aOR) = 2.46 95% Confidence Interval (CI) [1.47-4.13]), young maternal age (aOR = 2.29, 95% CI [1.18-4.46]), and absence of antiretroviral treatment for prophylaxis (aOR = 3.45, 95% CI [2.30-5.19]) were independently associated with LTFU among HIV-exposed infants. Factors associated with LTFU among HIV-unexposed infants included young maternal age (aOR = 1.96, 95% CI [1.36-2.81]), low maternal education level (aOR = 2.77, 95% CI [1.95-3.95]) and housewife/unemployed mothers (aOR = 1.56, 95% CI [1.16-2.11]).
  
  
  CONCLUSIONS
  Failure to return for at least one scheduled clinical visit is a problem especially among HIV-unexposed infants included in studies involving HIV-exposed infants. Factors associated with this type of LTFU included maternal characteristics, socio-economic status, quality of antenatal care and obstetrical context of delivery. Enhanced counselling in antenatal and intrapartum services is required for mothers at high risk of failure to return for follow-up visits.
authors.affiliation: Service d'Epidémiologie et de Santé Publique, Centre Pasteur du Cameroun, Membre du Réseau International des Instituts Pasteur, Yaoundé, Cameroun. lsidze@gmail.com.|ISPED, Université Victor Segalen, Bordeaux II, France. lsidze@gmail.com.
authors.forename: Larissa Kamgue
authors.initials: LK
authors.lastname: Sidze
authors.affiliation: Assistance Publique des Hôpitaux de Paris, Pédiatrie Générale, Hôpital Robert Debré, Paris, France. albert.faye@rdb.aphp.fr.|Université Paris 7 Denis Diderot, Paris Sorbonne Cité, Paris, France. albert.faye@rdb.aphp.fr.
authors.forename: Albert
authors.initials: A
authors.lastname: Faye
authors.affiliation: Service de Pédiatrie, Centre Hospitalier d'Essos, Yaoundé, Cameroun. ndiangsuzie@yahoo.fr.
authors.forename: Suzie Ndiang
authors.initials: SN
authors.lastname: Tetang
authors.affiliation: Hôpital de Jour, Hôpital Laquintinie, Douala, Cameroun. idapenda@yahoo.fr.|Faculté de Médecine et des Sciences Pharmaceutiques, Université de Douala, Douala, Cameroun. idapenda@yahoo.fr.
authors.forename: Ida
authors.initials: I
authors.lastname: Penda
authors.affiliation: Centre Mère et Enfant de la Fondation Chantal Biya, Yaoundé, Cameroun. guemgeorg@hotmail.com.
authors.forename: Georgette
authors.initials: G
authors.lastname: Guemkam
authors.affiliation: Centre Mère et Enfant de la Fondation Chantal Biya, Yaoundé, Cameroun. atebfranc@gmail.com.
authors.forename: Francis Ndongo
authors.initials: FN
authors.lastname: Ateba
authors.affiliation: Centre Mère et Enfant de la Fondation Chantal Biya, Yaoundé, Cameroun. jeanndongo@yahoo.fr.
authors.forename: Jean Audrey
authors.initials: JA
authors.lastname: Ndongo
authors.affiliation: Centre Mère et Enfant de la Fondation Chantal Biya, Yaoundé, Cameroun. dongfel@yahoo.fr.|Faculté de Médecine et des Sciences Biomédicales, Université de Yaoundé I, Yaoundé, Cameroun. dongfel@yahoo.fr.
authors.forename: Félicité
authors.initials: F
authors.lastname: Nguefack
authors.affiliation: Service d'Epidémiologie et de Santé Publique, Centre Pasteur du Cameroun, Membre du Réseau International des Instituts Pasteur, Yaoundé, Cameroun. texier@pasteur-yaounde.org.|SESSTIM (UMR 912), Université Aix-Marseille, Marseille, France. texier@pasteur-yaounde.org.
authors.forename: Gaëtan
authors.initials: G
authors.lastname: Texier
authors.affiliation: Service d'Epidémiologie et de Santé Publique, Centre Pasteur du Cameroun, Membre du Réseau International des Instituts Pasteur, Yaoundé, Cameroun. tchendjou@pasteur-yaounde.org.|ISPED, Université Victor Segalen, Bordeaux II, France. tchendjou@pasteur-yaounde.org.
authors.forename: Patrice
authors.initials: P
authors.lastname: Tchendjou
authors.affiliation: Service de Virologie, Centre Pasteur du Cameroun, Membre du Réseau International des Instituts Pasteur, Yaoundé, Cameroun. kfutwah@pasteur-yaounde.org.
authors.forename: Anfumbom
authors.initials: A
authors.lastname: Kfutwah
authors.affiliation: Equipe 4 (VIH et IST) - INSERM U1018 (CESP), Le Kremlin Bicêtre, Paris, France. josiane.warszawski@inserm.fr.|Assistance Publique des Hôpitaux de Paris, Service d'Epidémiologie et de Santé Publique, Hôpital de Bicêtre, Le Kremlin Bicêtre, Paris, France. josiane.warszawski@inserm.fr.|Université de Paris Sud 11, Paris, France. josiane.warszawski@inserm.fr.
authors.forename: Josiane
authors.initials: J
authors.lastname: Warszawski
authors.affiliation: Service d'Epidémiologie et de Santé Publique, Centre Pasteur du Cameroun, Membre du Réseau International des Instituts Pasteur, Yaoundé, Cameroun. tejiokem@pasteur-yaounde.org.|Equipe 4 (VIH et IST) - INSERM U1018 (CESP), Le Kremlin Bicêtre, Paris, France. tejiokem@pasteur-yaounde.org.
authors.forename: Mathurin Cyrille
authors.initials: MC
authors.lastname: Tejiokem
mesh_terms: D044966:Anti-Retroviral Agents / Q000008:administration & dosage*; D002163:Cameroon / Q000453:epidemiology; D002986:Clinical Trials as Topic; D036861:Delivery, Obstetric; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000517:prevention & control* / Q000635:transmission*; D006801:Humans; D007223:Infant; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D059012:Lost to Follow-Up; D009035:Mothers; D012959:Socioeconomic Factors
chemical_list: D044966:Anti-Retroviral Agents