Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, CA 94720, USA.
Institute for Social and Environmental Research-Nepal (ISER-N), Field Office, Amarsingh Chowk, Pokhara, Kaski, Nepal.
Environ Res. 2019 Jun;173:69-76. doi: 10.1016/j.envres.2019.03.024. Epub 2019 Mar 14.
The risk of developing latent tuberculosis infection (LTBI) associated with cooking with solid fuels is unknown. This study examined the relationship between household fuel uses and LTBI in adults living in Nepal, a country with a high incidence of tuberculosis.
Participants were 1088 adults aged 18-70 years, members of the control group of a population-based case-control study of pulmonary TB (PTB) in people without previous TB, living in Kaski and neighboring districts of Nepal. Participants were interviewed in their homes with a standardized questionnaire. Blood samples were tested for LTBI using an interferon-gamma release assay. Multivariate unconditional logistic regression was used to examine associations between household fuel sources and LTBI.
The overall prevalence of LTBI in the study population was 36%. Using liquefied petroleum gas (LPG) as the baseline cooking fuel type, the adjusted odds ratio (aOR) for using a primary wood cookstove was 1.13 (95%CI: 0.73,1.77) for all participants and, in women only, 1.14 (0.62, 2.09). Corresponding figures for biogas stoves were 0.64 (0.34,1.20) and 0.59 (0.24,1.45), respectively. Household sources of air pollution positively associated with LTBI included traditional oil lamps (diyos) used during power outages, for which the aOR in all participants was 2.53 (1.20, 5.31), although the number of users was small. Use of candles for lighting was also associated with increased risk of LTBI among men (aOR = 1.61, 95% CI:1.01, 2.56).
No association was found between use of wood for cooking and LTBI. However, there was some evidence that biogas cookstoves were associated with reduced odds of LTBI. Some exposures at the time of actual infection will have been different than the current exposures used in the analysis, biasing results towards the null. Results are sufficient for the use of diyos to be discouraged for lighting purposes. Overall, results suggest that household cooking fuel use is likely to have more effect on moving from the infected state to PTB than on becoming infected with the M. tuberculosis complex. Further research, including longitudinal studies with serial LTBI testing would be useful to more accurately assess the relationships between exposures and infection.
使用固体燃料烹饪与潜伏性结核感染（LTBI）的风险尚不清楚。本研究在一个结核病发病率较高的国家尼泊尔，调查了家庭燃料使用与成年人 LTBI 之间的关系。
研究对象为 1088 名年龄在 18-70 岁之间的成年人，他们是一项基于人群的肺结核病例对照研究（PTB）中未患过结核病的对照组成员，居住在尼泊尔卡斯基和邻近地区。研究人员使用标准化问卷在参与者家中对其进行了访谈。使用干扰素 - γ释放试验检测血液样本中 LTBI 的存在。使用多变量非条件逻辑回归分析家庭燃料来源与 LTBI 之间的关联。
研究人群中 LTBI 的总体患病率为 36%。以液化石油气（LPG）为基础烹饪燃料类型，在所有参与者中，使用主要木质炉灶的调整比值比（aOR）为 1.13（95%CI：0.73，1.77），仅在女性中为 1.14（0.62，2.09）。沼气炉的相应数字分别为 0.64（0.34，1.20）和 0.59（0.24，1.45）。与 LTBI 呈正相关的家庭空气污染来源包括在停电期间使用的传统油灯（diyos），所有参与者的 aOR 为 2.53（1.20，5.31），尽管使用者数量较少。使用蜡烛照明也与男性 LTBI 风险增加有关（aOR=1.61，95%CI：1.01，2.56）。
未发现烹饪用木材与 LTBI 之间存在关联。然而，有一些证据表明沼气炉灶与 LTBI 的几率降低有关。在实际感染时的一些暴露情况与分析中当前的暴露情况不同，这使结果偏向于零。这些结果足以说明不应鼓励使用 diyos 来照明。总体而言，结果表明，家庭烹饪燃料的使用可能对从感染状态发展为肺结核的影响更大，而不是对感染结核分枝杆菌复合体的影响更大。进一步的研究，包括具有连续 LTBI 检测的纵向研究，将有助于更准确地评估暴露与感染之间的关系。
