The effect of detecting undetected common mental disorders on psychological distress and quality of life in long-term sickness absence: a randomised controlled trial.
BACKGROUND
The burden imposed by common mental disorders on individuals and society calls for interventions aimed at reducing psychological distress and improving quality of life.


OBJECTIVE
To study whether detection of mental disorders plus feedback to individuals and caregivers reduces psychological distress and improves quality of life in long-term sickness absence (LSA), defined as continuous sick-leave for more than 8 weeks. Mental disorders were detected by Present State Examination.


METHODS
The study population comprised 118,000 inhabitants. During 1 year, all incident individuals on LSA were identified from public registers regarding sickness transfer income. Common Mental Disorders Screening Questionnaire (CMD-SQ) (psychological distress) and SF-36 (quality of life) were sent to 2414 incident individuals on LSA, response rate 46.7%. In a randomised controlled trial for individuals with a certain level of psychological distress, 420 participants were allocated to an intervention group and 416 to a control group. The dropout at 12-months follow-up was 22.4% in the intervention group and 13.9% in the control group.


RESULTS
There were no significant effects for individuals sick-listed with a psychiatric sick-leave diagnosis. For individuals without a psychiatric sick-leave diagnosis, significant effects were seen in the subscales of CMD-SQ (effect sizes: 0.20-0.28) and in more subscales of SF-36 (effect sizes: 0.12-0.22). The effects varied according to socio-demographic characteristics and somatic sick-leave diagnoses.


CONCLUSIONS
The intervention was most effective for individuals without a psychiatric sick-leave diagnosis sick-listed from full-time work. Thus, despite small effect sizes, the intervention may be efficient for large subgroups on LSA.
Søgaard
Hans Jørgen
HJ
Research Unit West, Centre for Psychiatric Research, Herning, Denmark. Hans-Joergen.Soegaard@ps.rm.dk
Bech
Per
P
D000328:Adult; D015897:Comorbidity; D017281:Cost of Illness; D003718:Denmark; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000150:complications / Q000175:diagnosis / Q000523:psychology*; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011788:Quality of Life; D012050:Rehabilitation, Vocational; D018582:Sick Leave; D012959:Socioeconomic Factors; D013315:Stress, Psychological; D011795:Surveys and Questionnaires