The Association Between Pay-as-you-go LPG Consumption and Respiratory Health Symptoms in an Informal Urban Settlement in Nairobi, Kenya

In sub-Saharan Africa, approximately 85% of individuals use biomass fuels (e.g., charcoal, wood) for cooking. While replacing biomass fuels with cleaner cooking fuels (e.g., liquefied petroleum gas (LPG)) can benefit respiratory health, the difference in respiratory symptom prevalence between exclusive and partial LPG use is uncertain. Smart meter data from 621 households using pay-as-you-go (PAYG) LPG in an informal settlement in Nairobi, Kenya, was linked to survey data (September-October 2022) detailing weekly biomass cooking fuel use. Multivariable Poisson regression with robust error variance examined the association between the proportion of weekly cooking with PAYG LPG (100% PAYG LPG, PAYG LPG used for 50-99% or 0-49% of weekly cooking) and self-reported presence of at least one respiratory symptom (cough, wheezing, chest tightness, shortness of breath, flu-like symptoms) during the previous 6 months. The model was adjusted for sociodemographic and cooking environment characteristics. In the final model, a dose-response increase in odds of at least one respiratory symptom existed among those using PAYG LPG for 50-99% of weekly cooking (1.19; 95% CI, 0.94-1.52) and 0-49% of cooking time (1.30; 95% CI, 1.11-1.51) compared with exclusive PAYG LPG users. Participants not concerned about the health effects of smoke exposure from cooking had significantly higher odds (1.44; 95% CI, 1.25-1.65) of respiratory symptoms than those who reported being concerned. Transitioning from partial to exclusive LPG use may improve primary cooks' respiratory health in urban settings. Educating individuals about the risks of biomass smoke exposure may modify behaviors to subsequently reduce respiratory symptom risk; this pathway requires further investigation.