Changes in self-regulatory driving among older drivers over time.

Objectives: The primary goal of the study was to identify to what extent older people modify their driving, what influences them to do so, and how self-regulatory behavior changes over time in relation to changes in perceived impairments and lifestyle characteristics.

Methods: Participants 65 and older (n = 2650) were recruited while renewing their driver's licenses in Connecticut, Kentucky, and Rhode Island and were interviewed by telephone about current driving patterns, recent changes in driving, functional abilities related to driving (i.e., vision, memory, physical mobility, diagnosed medical conditions), crash involvements, and lifestyle characteristics. Participants were called annually to participate in follow-up telephone interviews; 2057 completed a second interview, 1698 completed 3 interviews, and 1437 completed all 4 interviews. Stepwise regression analyses examined how changes in impairments and life events (i.e., retiring, becoming widowed or divorced) related to changes in the number of miles driven during a typical week and in the number of driving situations avoided.

Results: Based on information provided in the initial survey, participants who completed all 4 surveys were slightly younger, more likely to be married, slightly less impaired in terms of physical mobility and medical conditions, and drove more weekly miles and avoided fewer driving situations compared with those who dropped out. Participants who completed all 4 interviews reported driving an average of 94 miles per week in year 1 compared with 78 miles in year 4. Reported impairments generally were low to moderate and changed little. Analyses comparing years 1 and 4 indicated that drivers drove 35 fewer miles per week if they retired or lost their job and 61 fewer miles if they moved from a retirement home to a private home or assisted living. They drove 25 more miles per week on average if they became widowed or divorced. Small increases in the number of driving situations avoided were associated with increasing impairments in memory and mobility.

Conclusions: Lifestyle changes such as becoming widowed or divorced or retiring were associated with changes in mileages. Older drivers with worsening memory and physical mobility regulated their driving to some extent by avoiding more driving situations, confirming the hypothesis that some older drivers do take steps to compensate for increases in some perceived impairments. However, during the 3-year study period, reported changes were not large, perhaps because older drivers with larger changes were among those who dropped out (46% of those who took the first survey).