School of Public Health, The University of Hong Kong, Hong Kong, Hong Kong SAR, China.
School of Nursing and Health Studies, Hong Kong Metropolitan University, Hong Kong, Hong Kong SAR, China.
Front Public Health. 2023 Jul 13;11:1136621. doi: 10.3389/fpubh.2023.1136621. eCollection 2023.
Mask-wearing in outdoor public places in Hong Kong was mandated on 29 July 2020, amid the COVID-19 pandemic. We aimed to evaluate the impact of mandatory masking with no exemption for smoking on outdoor smoking.
We conducted 253 unobtrusive observations at 10 outdoor smoking hotspots in 33 months from July 2019 to March 2022 and counted smokers and non-smoking pedestrians in fixed boundaries. We conducted interrupted time-series analyses on the monthly mean volume of smokers (persons per hour) using generalized linear models. The independent variables were as follows: time since the first observation, implementation of the mask regulation, time since the regulation, seasonality, and waves 1-5 outbreaks. We checked the robustness of the association using the daily mean volume of smokers as the dependent variable. Two sensitivity analyses were conducted to include the hotspot location or the number of all pedestrians as an offset.
Monthly outdoor smoking decreased immediately after the regulation (incidence rate ratio [IRR]: 0.505, 95% confidence interval [CI]: 0.374 to 0.680, < 0.001). Daily smoking analysis and the two sensitivity analyses supported the results. However, monthly outdoor smoking increased by 11% since the regulation (IRR: 1.110, 95% CI: 1.074 to 1.147, < 0.001). An exception was observed at the most severe wave 5 outbreak when monthly outdoor smoking decreased (IRR: 0.415, 95% CI: 0.327 to 0.525, < 0.001).
Outdoor smoking fell immediately after mandatory masking, rebounded to pre-pandemic levels, and decreased again at the most severe wave 5.
2020 年 7 月 29 日，香港新冠疫情期间，户外公共场所强制佩戴口罩。我们旨在评估无吸烟豁免的户外强制戴口罩对户外吸烟的影响。
我们在 2019 年 7 月至 2022 年 3 月的 33 个月内，在 10 个户外吸烟热点进行了 253 次非干扰性观察，在固定边界内计算吸烟者和非吸烟行人人数。我们使用广义线性模型对每月平均吸烟者人数（每小时人数）进行了中断时间序列分析。自变量如下：第一次观察以来的时间、口罩规定的实施、规定以来的时间、季节性和第 1-5 波爆发。我们使用每日平均吸烟者人数作为因变量进行了稳健性检查。进行了两项敏感性分析，包括将热点位置或所有行人人数作为偏移量。
规定出台后，户外吸烟立即减少（发病率比 [IRR]：0.505，95%置信区间 [CI]：0.374 至 0.680，<0.001）。每日吸烟分析和两项敏感性分析支持这一结果。然而，自规定出台以来，户外吸烟每月增加 11%（IRR：1.110，95% CI：1.074 至 1.147，<0.001）。在最严重的第 5 波爆发期间，观察到例外情况，户外吸烟减少（IRR：0.415，95% CI：0.327 至 0.525，<0.001）。
户外强制戴口罩后，吸烟立即减少，反弹至疫情前水平，在最严重的第 5 波时再次下降。
