Based on self-determination theory and adaptation theories, the study aim was to investigate the relationship between need fulfillment (of autonomy, relatedness, and competence), need importance, and depressive symptoms during the first months of living in a nursing home.

Eight-month longitudinal questionnaire study in which 75 persons newly admitted to units for physically frail residents participated at baseline. Twenty-three longitudinal participants were remaining at the third and final measurement wave.

The results show a main effect of need fulfillment and an interaction effect of need fulfillment and need importance on depressive symptoms over time. A prototypical plot shows that residents with low need fulfillment had higher initial levels of depressive symptoms that decreased modestly over time, regardless of their need importance. Residents with high need fulfillment had lower initial levels of depressive symptoms, but their trajectories differed for participants with low and high need importance. Residents with low need importance started with lower levels of depressive symptoms but remained stable over time, whereas residents with high need importance had more depressive symptoms at T1 that decreased slightly over time.

In general, depressive symptoms do not change over time. However, individual trajectories of depressive symptoms seem to depend on individual need fulfillment and need importance. The residents that consider need fulfillment to be highly important but experience low need fulfillment had higher initial levels of depressive symptoms that decreased modestly over time, although the level of depressive symptoms remained higher as compared to the other residents.