Current and Desired Quality of Life in People with Parkinson’s Disease: The Calman Gap Increases with Depression

Hopes and expectations often differ from current experiences. This so-called Calman gap influences quality of life (QoL). We investigated this gap in 77 elderly patients with Parkinson’s disease (PD), 25 patients with epilepsy, and 39 age-matched healthy older adults using a novel QoL questionnaire, where current and desired states were marked on a visual analogue scale. We studied the relationships between (1) epidemiological factors, (2) current and desired QoL, as well as the difference between the latter two. Current QoL was determined by depression, education level, living situation, and condition (PD, epilepsy, control). In contrast, desired QoL was essentially determined by the presence of a disease (condition), education level, and age, but not by depression. In particular, the presence of PD, lower education level, and higher age was correlated with lower expectations. In patients with PD, the gap between the current and desired QoL was largest for pain and physical functions. Accordingly, the significant effects of depression were observed only for mean current QoL, but not for desired QoL. Therefore, depression mainly influences current but not desired QoL in patients with PD. Depressed patients with PD had significantly worse QoL than PD patients without depression, although they both had almost the same desired QoL and hence, depressed PD patients had a larger Calman gap between current and desired QoL.