Community health workers and environmental interventions for children with asthma: a systematic review.

Community health worker (CHW)-delivered, home-based environmental interventions for pediatric asthma were systematically reviewed. Seven PubMed/MEDLINE listed randomized controlled trials that encompassed the following intervention criteria were identified: (1) home-based; (2) delivered by a CHW; (3) delivered to families with children with asthma; and (4) addressed multiple environmental triggers for asthma. Details of research design, intervention type, and setting, interventionist, population served, and the evaluated outcomes were abstracted. Outcome assessment was broad and non-uniform. Categories included direct mediators of improved health outcomes, such as trigger-related knowledge, trigger reduction behaviors and allergen or exposure levels, and asthma-related health outcomes: change in lung function, medication use, asthma symptoms, activity limitations, and health care utilization. Indirect mediators of health outcomes, or psychosocial influences on health, were measured in few studies. Overall, the studies consistently identified positive outcomes associated with CHW-delivered interventions, including decreased asthma symptoms, daytime activity limitations, and emergency and urgent care use. However, improvements in trigger reduction behaviors and allergen levels, hypothesized mediators of these outcomes, were inconsistent. Trigger reduction behaviors appeared to be tied to study-based resource provision. To better understand the mechanism through which CHW-led environmental interventions cause a change in asthma-related health outcomes, information on the theoretical concepts that mediate behavior change in trigger control (self-efficacy, social support) is needed. In addition, evaluating the influence of CHWs as clinic liaisons that enhance access to health professionals, complement clinic-based teaching, and improve appropriate use of asthma medications should be considered, alongside their effect on environmental management. A conceptual model identifying pathways for future investigation is presented.