Sitting time not associated with heart disease
In mid-aged women, sitting time does not appear to be associated with the risk of heart disease. These findings are contrary to expectations, given the growing evidence of a relationship between sitting time and heart disease. Research in this area is scarce and additional studies are needed to confirm or refute these findings.
What is this research about?
In Westernised societies, adults are increasingly spending long periods in sedentary behaviours such as sitting. Although there is growing evidence on the relationship between television/ screen time and increased risk of heart disease, very little is known about the association between total sitting time (in different domains) and heart disease.
A recent review showed people engaged in sedentary behaviors have a 90 per cent increased risk of dying from heart disease. Three studies found a significant association between TV viewing time and heart disease risk, while one study found heart disease risk higher in women who sat for 16 hours per day compared with those who sat for less than four hours.
What did the researchers do?
This study investigated the association of sitting time and heart disease rates among mid-aged Australian women. Researchers collected data from 6154 women (born 1946-51) in the Australian Longitudinal Study on Women’s Health who were free of heart disease in 2001.
The women answered questions about their total time spent sitting, including watching TV, driving, working at a desk and visiting with friends in surveys completed at three-yearly intervals from 1998 to 2010. Other factors investigated were demographics and lifestyle factors including alcohol consumption, physical activity and smoking.
What did the research find?
Researchers found no significant association between sitting time and heart disease among mid-aged women. These findings were contrary to those expected, given the growing evidence of a relationship between sitting time and heart disease.
This contradiction may be because the participants in this study were less sedentary than in some other study populations, with an average sitting time of 5.4 hours per day (highest sitting time 8.4 hours per day) which may be too low to detect a significant effect on heart disease. Despite the women being followed for nine years (2001-2010), sitting time may take longer to impact on heart disease.
How can you use this research?
This research did not find an association between sitting time and heart disease. Research in this area is scarce and additional large, population-based studies in different settings, age-groups and study populations are needed to confirm or refute our findings.
Citation:
Herber-Gast et al. International Journal of Behavioral Nutrition and Physical Activity 2013, 10:55 doi:10.1186/1479-5868-10-55