Summary 
background Inactivity is a major problem in long-stay patients with severe mental illness. Very little research has been done into the variables that can predict and explain this inactivity.
aim To find associations between inactivity and the variables (psychiatric, pharmacological, lifestyle and comorbidity) of patients with severe mental health illness.methods A cross-sectional study was performed at ‘Zon en Schild’, a centre for mental health care in Amersfoort in the Netherlands. The study included 100 long-stay psychiatric patients hospitalized throughout the period February 2011 till July 2011. All of these patients were being treated with antipsychotics and were long-term inpatients at a psychiatric clinic. At the out-patient clinic of ‘Zon en Schild’ they were screened for inactivity via a subscale of the Nurses’ Observation Scale for Inpatient Evaluation (NOSIE-30). Data were collected and analysed by means of a validated questionnaire, physical examination and patient records. Simple and multiple regression analyses were performed in order to find associated factors associated with inactivity.
results We found that 31.3% of the variance predicted by the multiple regression analysis model for inactivity was associated with the variables parkinsonism, negative symptoms, metabolic syndrome, diabetes, body-mass index (BMI), first-generation antipsychotics and combination of first- and second-generation antipsychotics. Age (β=0.235, p=0.04) and a combination therapy involving traditional and atypical antipsychotics (β=0.317, p=0.04) were significantly associated with inactivity.
conclusion Age and the combination of first- and second-generation antipsychotics were associated with inactivity. Cross-sectional studies do not demonstrate any causal links, but can generate a hypothesis. One possible hypothesis for the surprising link between inactivity and the combination of traditional and atypical antipsychotics is that the combination of antipsychotics promotes and fosters inactivity.key words clinical, epidemiology, inactivity, long-term care, schizophrenia