Prevalence and cognitive underpinnings of isolated apathy in young healthy subjects

Apathy is well described in neurodegenerative conditions, however to date there is no evidence of significant isolated apathy in subjects free from other neurological and psychiatric co-morbidites. Identifying isolated apathy in subjects free from neuropsychiatric conditions could contribute to refining current concepts of apathy and reevaluate its nosological classification as an independent clinical syndrome.

We assessed apathy and perceived quality of life in a group of 2751 adults (age 19-40 years) free from neuropsychiatric or medical conditions. Subjects with and without elevated apathy were compared on measures of depression, self-efficacy, behavioral inhibition, and behavioral activation.

Observed prevalence of isolated elevated apathy was 1.45%. Subjects with apathy presented with reduced quality of life and lower behavioral activation compared to apathy-free subjects, while there was no difference between the two groups on measures of depression, self-efficacy, and perceived social skills.

The main limitation of this study is the use of self-report questionnaires.

Isolated, ecologically-relevant apathy can be found in adults independently from the presence of subclinical depression or of concurrent medical conditions. Apathy screening should be considered in the evaluation of young non-depressed subjects with reduced perceived quality of life.