The Effects of an Acute Stressor on Depressive Symptoms among Older Adults: The Moderating Effects of Social Support and Age

This study uses longitudinal data to examine the potential moderating effects of social support and age among older adults exposed to an acute stressor. Using a sample of 651 older persons, data were gathered in the spring of 1992 and in the fall of 1993, approximately 60 days after the peak impact of flooding in the Midwest. Results indicate a positive association between preand post-flood depression and a negative association between social support and post-flood depression. For the youngest of the two older age groups, there is also a positive association between flood exposure and post-flood depression, controlling for prior levels of depression. Age interactions reveal that social support moderates the effects of flood exposure on depression only for the younger age group. Research has demonstrated the negative effects that acute stressors, such as natural disasters, have on mental health. Some of these negative outcomes include anxiety, depression, and post-traumatic stress disorder (Canino et al. 1990; Phifer 1990; Phifer and Norris 143 An earlier version of this article was presented at the International Conference on Personal Relationships in Banff, Canada, August 1996. This article is based on research supported by the National Institute of Mental Health (MH48165). Corresponding author — Kimberly A. Tyler. 144 Ty l e r & Ho y T i n Re s e a R c h o n ag i n g 22 (2000) 1989). Although the level of exposure and the severity of the event influence the magnitude of effects, natural disasters have been found to influence mental health (Bravo et al. 1990; Phifer and Norris 1989). Compared with other acute stressors, exposure to flooding has been found to be a major life stressor with persistent effects. In general, exposure to natural disasters has global and long-lasting effects on social and economic resources (Phifer and Norris 1989). This article takes advantage of a unique set of circumstances to permit a longitudinal investigation of the impact of these types of stressors among an older population. In the spring of 1992, the Iowa Health Poll, which examined mental health and health needs and services in rural and urban Iowa, was administered to respondents. During the summer of 1993, Iowa residents experienced extensive flooding. This was one of the worst floods in the state’s history, and Iowa was declared a disaster area in July 1993. Immediately following the floods, funding was secured to conduct a follow-up survey whereby respondents of the first survey were contacted and requested to participate in a second interview, which provided for a prospective study of the effects of an acute stressor in a population survey. Using these data, we were able to control for prior levels of symptoms and stressors, which is important when making projections about the effects of an acute stressor on current depressive levels. Floods are not equal opportunity disasters. Persons exposed to floods are more likely to live in low-income areas or neighborhoods in flood-prone regions. Thus, post-flood depression could reflect prior economic stress and related problems. A prospective study design permits us to control for this possibility. This approach is also beneficial because research indicates that levels of depression may vary by age. Controlling for previous depression levels allows us to look at change in depression rather than the level of depression, which may reflect age or cohort differences (Mirowsky and Ross 1992).