Spending time online has the potential to ward off depression among retirees, particularly among those who live alone, according to research published online in The Journals of Gerontology, Series B: Psychological Sciences and Social Sciences. In the article "Internet Use and Depression Among Retired Older Adults in the United States: A Longitudinal Analysis," the authors report that Internet use reduced the probability of a depressed state by 33 percent among their study sample.

Late-life depression affects between 5 and 10 million Americans age 50 and older. This new study shows that the Internet offers older Americans a chance to overcome the social and spatial boundaries that are believed to fuel depression.

The research was conducted by Shelia R. Cotten, PhD, of Michigan State University; George Ford, PhD, of the Phoenix Center for Advanced Legal & Economic Public Policy Studies; Sherry Ford, PhD, of the University of Montevallo; and Timothy M. Hale, PhD, of the Center for Connected Health and Harvard Medical School.

"Retired persons are a population of interest, particularly because one mechanism by which Internet use may affect depression is to counter the effects of isolation and loneliness, which are more common among older adults," the authors stated. "Also, working individuals may be required to use the Internet rather than choosing to, and may use the technology for different reasons than those not working."

The data were obtained from four waves of the Health and Retirement Study, a longitudinal survey collecting information from more than 22,000 older Americans every two years. The current study sample included 3,075 community-dwelling respondents observed over 4 waves of data, from 2002 to 2008, yielding a total of 12,300 observations.

The measurement of Internet use was based on a question asking participants, "Do you regularly use the World Wide Web, or the Internet, for sending and receiving e-mail or for any other purpose?" Depression was measured using an eight-item version of the Center for Epidemiologic Studies Depression Scale.

With other factors constant, the authors found that Internet users had an average predicted probability of depression of .07, whereas that probability for nonusers was .105. Based on the difference, Internet use led to a 33 percent reduction in the probability of depression.

"Number of people in the household partially mediates this relationship, with the reduction in depression largest for people living alone," the authors wrote. "This provides some evidence that the mechanism linking Internet use to depression is the remediation of social isolation and loneliness. Encouraging older adults to use the Internet may help decrease isolation, loneliness, and depression."