Protocol of an individual participant data meta-analysis to quantify the impact of high ambient temperatures on maternal and child health in Africa (HE2AT IPD)

INTRODUCTION

Globally, recognition is growing of the harmful impacts of high ambient temperatures (heat) on health in pregnant women and children. There remain, however, major evidence gaps on the extent to which heat increases the risks for adverse health outcomes, and how this varies between settings. Evidence gaps are especially large in Africa. We will conduct an individual participant data (IPD) meta-analysis to quantify the impacts of heat on maternal and child health in sub-Saharan Africa. A detailed understanding and quantification of linkages between heat, and maternal and child health is essential for developing solutions to this critical research and policy area.

METHODS AND ANALYSIS

We will use IPD from existing, large, longitudinal trial and cohort studies, on pregnant women and children from sub-Saharan Africa. We will systematically identify eligible studies through a mapping review, searching data repositories, and suggestions from experts. IPD will be acquired from data repositories, or through collaboration with data providers. Existing satellite imagery, climate reanalysis data, and station-based weather observations will be used to quantify weather and environmental exposures. IPD will be recoded and harmonised before being linked with climate, environmental, and socioeconomic data by location and time. Adopting a one-stage and two-stage meta-analysis method, analytical models such as time-to-event analysis, generalised additive models, and machine learning approaches will be employed to quantify associations between exposure to heat and adverse maternal and child health outcomes.

ETHICS AND DISSEMINATION

The study has been approved by ethics committees. There is minimal risk to study participants. Participant privacy is protected through the anonymisation of data for analysis, secure data transfer and restricted access. Findings will be disseminated through conferences, journal publications, related policy and research fora, and data may be shared in accordance with data sharing policies of the National Institutes of Health.

PROSPERO REGISTRATION NUMBER

CRD42022346068.

Emerging climate change-related public health challenges in Africa: A case study of the heat-health vulnerability of informal settlement residents in Dar es Salaam, Tanzania

Heat has the potential to become one of the most significant public health impacts of climate change in the coming decades. Increases in temperature have been linked to both increasing mortality and morbidity. Cities have been recognized as areas of particular vulnerability to heat's impacts on health, and marginalized groups, such as the poor, appear to have higher heat-related morbidity and mortality. Little research has examined the heat vulnerability of urban informal settlements residents in Africa, even though surface temperatures across Africa are projected to increase at a rate faster than the global average. This paper addresses this knowledge gap through a mixed-methods analysis of the heat-health vulnerability of informal settlement residents in Dar es Salaam, Tanzania. The heat exposure, sensitivity and adaptive capacity of informal settlement residents were assessed through a combination of climate analyses, semi-structured interviews with local government actors and informal settlement residents, unstructured interviews with health sector respondents, a health impacts literature review, and a stakeholder engagement workshop. The results suggest that increasing temperatures due to climate change will likely be a significant risk to human health in Dar es Salaam, even though the city does not reach extreme temperature conditions, because informal settlement residents have high exposure, high sensitivity and low adaptive capacity to heat, and because the heat-health relationship is currently an under-prioritized policy issue. While numerous urban planning approaches can play a key role in increasing the resilience of citizens to heat, Dar es Salaam's past and current growth and development patterns greatly complicate the implementation and enforcement of such approaches. For African cities, the findings highlight an urgent need for more research on the vulnerability and resilience of residents to heat-health impacts, because many African cities are likely to present similar characteristics to those in Dar es Salaam that increase resident's vulnerability.