Risk factors for mortality from pneumonia in children in low and middle income countries: systematic review (protocol and preliminary results).

Background Pneumonia is the most common cause of mortality in children under five years of age. Aims To systematically review the evidence on the risk factors for death from pneumonia in children in low and middle income countries. Methods We will searched MEDLINE, EMBASE, LILACS, CINAHL, BIBLIOMAP, POPLINE, for published studies. For ongoing studies we will search the WHO Platform (ICTRP), MetaRegister of Controlled Trials (mRCT), Current Controlled Trials (CCT). We will contact a list researchers working in the field, technical bodies and academic institutions. We will include for evaluation the following types of risk factors: a) Biological; b) Related to the disease; c) Environmental; d) Socio-economical; e) Health Services factors. Two authors will assess study eligibility and methodological quality and extract and analyse data. Where appropriate, we will combined data in meta-analyses (random-effects model) and assess heterogeneity. Heterogeneity will be explored by subgroup analysis, and if appropriate, by meta-regression. Results We identified so far 58 studies, including 66,775 children, both in hospital and community setting. Preliminary results show that factors significantly related to mortality pertain to all five categories evaluated: a) Biological factors (age, birth-weight, malnutrition, co-morbidities such as HIV, sepsis, diarrhoea -with some heterogeneity among studies, anaemia, rickets); b) Factors related to the disease (severity of pneumonia, hypoxia, disease duration, disease extension, bacterial disease); c) Environmental factors (indoor pollution); d) Socio-economical factors (maternal education); e) Health Services factors (health-worker visit, previous treatment). Conclusion Final results of this work will be available for presentation at the meeting.