Skalická Věra, Ringdal Kristen, Witvliet Margot I
Department of Sociology and Political Science, Norwegian University of Science and Technology, Trondheim, Norway.
PLoS One. 2015 Apr 8;10(4):e0124690. doi: 10.1371/journal.pone.0124690. eCollection 2015.
Socioeconomic inequalities in mortality can be explained by different groups of risk factors. However, little is known whether repeated measurement of risk factors can provide better explanation of socioeconomic inequalities in health. Our study examines the extent to which relative educational and income inequalities in mortality might be explained by explanatory risk factors (behavioral, psychosocial, biomedical risk factors and employment) measured at two points in time, as compared to one measurement at baseline.
From the Norwegian total county population-based HUNT Study (years 1984-86 and 1995-1997, respectively) 61 513 men and women aged 25-80 (82.5% of all enrolled) were followed-up for mortality in 25 years until 2009, employing a discrete time survival analysis. Socioeconomic inequalities in mortality were observed. As compared to their highest socioeconomic counterparts, the lowest educated men had an OR (odds ratio) of 1.41 (95% CI 1.29-1.55) and for the lowest income quartile OR = 1.59 (1.48-1.571), for women OR = 1.35 (1.17-1.55), and OR = 1.40 (1.28-1.52), respectively. Baseline explanatory variables attenuated the association between education and income with mortality by 54% and 54% in men, respectively, and by 69% and 18% in women. After entering time-varying variables, this attainment increased to 63% and 59% in men, respectively, and to 25% (income) in women, with no improvement in regard to education in women. Change in biomedical factors and employment did not amend the explanation.
Addition of a second measurement for risk factors provided only a modest improvement in explaining educational and income inequalities in mortality in Norwegian men and women. Accounting for change in behavior provided the largest improvement in explained inequalities in mortality for both men and women, as compared to measurement at baseline. Psychosocial factors explained the largest share of income inequalities in mortality for men, but repeated measurement of these factors contributed only to modest improvement in explanation. Further comparative research on the relative importance of explanatory pathways assessed over time is needed.
死亡率方面的社会经济不平等可由不同类别的风险因素来解释。然而，对于重复测量风险因素是否能更好地解释健康方面的社会经济不平等，人们知之甚少。我们的研究考察了与在基线时进行一次测量相比，在两个时间点测量的解释性风险因素（行为、心理社会、生物医学风险因素及就业情况）能在多大程度上解释死亡率方面的相对教育和收入不平等。
从挪威基于全国郡县人口的HUNT研究（分别为1984 - 1986年和1995 - 1997年）中选取了61513名年龄在25 - 80岁的男性和女性（占所有登记人员的82.5%），采用离散时间生存分析对其进行长达25年直至2009年的死亡率随访。观察到了死亡率方面的社会经济不平等现象。与社会经济地位最高的人群相比，受教育程度最低的男性的优势比（OR）为1.41（95%置信区间1.29 - 1.55），收入处于最低四分位数的男性的OR = 1.59（1.48 - 1.571），女性的OR分别为1.35（1.17 - 1.55）和1.40（1.28 - 1.52）。基线解释变量使男性中教育和收入与死亡率之间的关联分别减弱了54%和54%，女性中分别减弱了69%和18%。纳入随时间变化的变量后，男性的这一比例分别增至63%和59%，女性中收入方面增至25%，而女性在教育方面并无改善。生物医学因素和就业情况的变化并未改变解释效果。
对风险因素进行第二次测量在解释挪威男性和女性死亡率方面的教育和收入不平等时，仅带来了适度的改善。与在基线时测量相比，考虑行为变化在解释男性和女性死亡率不平等方面带来的改善最大。心理社会因素在解释男性死亡率方面的收入不平等中占比最大，但对这些因素进行重复测量仅在解释方面带来了适度的改善。需要对随时间评估的解释途径的相对重要性进行进一步的比较研究。
