Depression and loneliness may predict work inefficiency among professionally active adults

PURPOSE: Both depression and loneliness have been recognized as major public health issues, yet investigation into their role among young and middle-aged, professionally active persons is still required. The aim of the present study was to evaluate whether depression and loneliness may independently predict inefficiency at work among professionally active adults. METHODS: This is a cross-sectional study on a representative, nationwide sample. 1795 questionnaires were gathered from among professionally active adults from Poland from 1 to 31 July 2018 with a direct pen-and-paper interview. The sample was chosen by means of the stratified random method. The survey included a Patient Health Questionnaire (PHQ-9) to measure depression and questions, devised by the authors, relating to loneliness and inefficiency at work. Regression models were constructed with depression and loneliness as predictors of inefficiency at work, unadjusted and adjusted for selected sociodemographic, health- and work-related factors. RESULTS: In the unadjusted models, both depression and loneliness were independently associated with an increase of work inefficiency and absence from work, with effect sizes being higher for loneliness than for depression. After accounting for the control variables (i.e., sociodemographic, work- and health-related factors), the PHQ-9 score, but not the loneliness score, was associated with an increased probability of frequent thoughts about changing or leaving a job. CONCLUSION: Depression and loneliness independently predicted occupational functioning and differentially affect its various aspects. Counteracting depression and loneliness among employees should be regarded as a public health priority. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00420-022-01869-1.