A recent study by Mirza et al (2016) published in The Lancet Psychiatry with an accompany editorial (Reppermund, 2016) suggests that older people whose depression symptoms increase over time are at increased risk of developing dementia. According to the authors of this study, they come closer to establishing whether depression is a risk factor for dementia, or vice versa, because they follow a group of people with depressive symptoms over time, rather than assessing them at one time point.