Biostatistics Department, Harvard School of Public Health, Boston, MA, USA.
Am J Epidemiol. 2012 Oct 1;176(7):642-8. doi: 10.1093/aje/kws267. Epub 2012 Sep 17.
Restrictions on smoking in public places have become increasingly widespread in the United States, particularly since the year 2005. National-scale studies in Europe and local-scale studies in the United States have found decreases in hospital admissions for acute myocardial infarction (AMI) following smoking bans. The authors analyzed AMI admission rates for the years 1999-2008 in 387 US counties that enacted comprehensive smoking bans across 9 US states, using a study population of approximately 6 million Medicare enrollees aged 65 years or older. Effects of smoking bans on AMI admissions were estimated by using Poisson regression with linear and nonlinear adjustment for secular trend and random effects at the county level. Under the assumption of linearity in the secular trend of declining AMI, smoking bans were associated with a statistically significant ban-associated decrease in admissions for AMI in the 12 months following the ban. However, the estimated effect was attenuated to nearly zero when the assumption of linearity in the underlying trend was relaxed. This analysis demonstrates that estimation of potential health benefits associated with comprehensive smoking bans is challenged by the need to adjust for nonlinearity in secular trend.
在美国，公共场所的吸烟限制越来越普遍，尤其是自 2005 年以来。欧洲的国家规模研究和美国的地方规模研究都发现，在实施禁烟令后，急性心肌梗死（AMI）的住院人数有所减少。作者分析了 1999 年至 2008 年间美国 9 个州的 387 个县实施全面禁烟令后 AMI 入院率，研究人群约为 600 万 Medicare 参保者，年龄在 65 岁或以上。采用泊松回归，对季节性趋势进行线性和非线性调整，并对县级的随机效应进行调整，以估计禁烟令对 AMI 入院率的影响。在假设 AMI 呈下降趋势的季节性趋势具有线性的情况下，禁烟令与禁令实施后 12 个月内 AMI 入院率的显著下降相关。然而，当放宽对潜在趋势的线性假设时，估计效果几乎降为零。这项分析表明，全面禁烟令可能带来的健康益处的估计受到需要调整季节性趋势非线性的挑战。
