Patients who were optimistic two weeks after an acute coronary syndrome were more likely to be physically active and less likely to be readmitted to a hospital for cardiovascular reasons, according to a prospective, observational study.
The researchers also found that gratitude following an acute coronary syndrome was not associated with improvements in physical activity or readmissions.
Lead author Jeff C. Huffman, MD, of Harvard Medical School, and colleagues published their results online in Circulation: Cardiovascular Quality and Outcomes on Dec. 8.
Each year, more than 2.5 million people worldwide are hospitalized for an acute coronary syndrome such as MI or unstable angina. Approximately 20 percent will be later hospitalized for ischemic heart disease or suffer mortality within a year, according to the researchers.
In this study, they evaluated 164 participants who were hospitalized for an acute coronary syndrome between September 2012 and January 2014 at one of three cardiac units at an urban academic medical center.
After enrolling in the hospital, participants completed a detailed measure of their preadmission physical activity using the 7-day Physical Activity Recall Scale, which has been used for 30 years. At two weeks, they completed self-report measures and had their blood collected. They then wore accelerometers to measure their physical activity. At six months, they had their biomarkers collected and completed another self-report.
The primary outcome was physical activity at six months as measured by an accelerometer.
The researchers defined optimism as “a general expectation that the future will be favorable” and gratitude as “a disposition toward appreciating and being thankful for people, events, and experiences in one’s life.”
They measured optimism using the 6-item Life Orientation Test-Revised and gratitude using the Gratitude Questionnaire-6.
Of the 164 participants, 153 had adequate physical activity data and 152 had biomarker data available at six months. The mean age was 61.5 years old, while 84 percent of participants were men and 84 percent were white.
Participants took a mean of 5,147 steps per day. After controlling for social and medical variables, the researchers noted that optimism at two weeks was significantly associated with greater physical activity at six months.
Meanwhile, gratitude (GQ-6) was not associated with an increase in physical activity. There were also no significant differences between men and women or between white and non-white participants when it came to the association between gratitude or optimism and physical activity.
During the six months of follow-up, 21.3 percent of participant were readmitted to the hospital for any cause and 17.1 percent had a nonelective cardiac readmission. The researchers noted optimism was marginally associated with nonelective cardiac readmissions.
The researchers mentioned that the study occurred at a single academic center and enrolled a majority of white men, so the results may be generalizable to a larger population. They also said that they measured steps per day instead of overall observed activity and that they did not obtain data on other health behaviors. Further, they said that the six month follow-up period was short and may have limited analytic power.
“Despite these limitations, this study suggests a distinct contribution of optimism to increased physical activity and readmission reduction during the critical post-[acute coronary syndrome] period,” the researchers wrote. “The effects of optimism on physical activity were above and beyond the adverse effects of depression and anxiety, and were in contrast to gratitude, which was not linked to outcomes. These findings suggest that optimism, if measured shortly after an [acute coronary syndrome], could be used as a novel predictor of reduced physical activity or readmissions.”