There is evidence from large long-term randomized controlled
trials that quality of life of chronically ill patients slowly
deteriorates over time, especially in the placebo groups but
sometimes also in the intervention groups [36,37]. Although
physical quality of life also deteriorated among patients in our
study, we expect that improvements in health behavior (physical
activity and smoking) will prevent or slow down the deterioration
of physical quality of life normally seen in a chronic illness
population. Qualitative research indicated many of the aspects of
DMPs targeted at improving health behavior are expected to have
a longer-term impact on quality of life. In a meta-analysis of
interventions based on the CCM to improve care for chronic
illnesses Tsai and colleagues [23] found that the evidence on
quality of life outcomes was mixed. Condition-specific quality of
life scales are known to be more sensitive to changes in clinical
status compared to generic measures of quality of life such as the
SF-36. However, we have chosen the latter, because the generic
quality of life measures can be used in a wide variety of diseases, as
was the case in our project. Moreover, generic quality of life
measures may be more sensitive to long-term benefits of chronic
care interventions, especially when life style improvements
impact multiple morbidities simultaneously. The sustained
ability of practices to ‘‘offer more’’ by incorporating aspects
associated with DMPs into regular practice and by expanding
activities beyond the care setting and into the community is
important in this regard as is the focus on patient-led communication.