Understanding the Link Between Psychological Distress and Dementia

Dementia is a broad term for many neurodegenerative diseases that can impair cognition and memory. The WHO notes that approximately 55 million people in the world have dementia, with the number expected to double every 20 years. Understanding risk factors for dementia can help improve the diagnostic pathway, speed up interventions, and improve prognosis. A recent study published in JAMA Network Open identified psychological distress as a dementia risk factor after analyzing the link between the two.

The study was a population-based cohort study looking at 67,688 people in Finland. Researchers collected data from the National FINRISK Study from 1972, 1977, 19822, 1987, 1992, 1997, 2002, and 2007.

Patient stress levels were assessed based on their response to a question asking them to reflect on whether they experienced tension, stress, or strain in the past month. Responses were scored from one to four, with one indicating that they have, and their life is “almost unbearable” and four suggesting that they haven’t experienced any stress. Respondents were grouped with those responding one or two in one group and those responding three or four in another group.

Additional assessments of depressive mood, nervousness, and exhaustion were conducted, in which patients were questioned on the frequency of feelings of depression, tension, nervousness, and exhaustion. Patients answered on a scale of one to three, with one indicating often and three indicating never.

Researchers then conducted a statistical analysis using a Poisson and Fine–Gray model. Across both models, psychological distress was associated with an increased incidence of dementia. Based on the Poisson model, high exhaustion rates were associated with a 17% increase in dementia prevalence. Additionally, stress was linked with a 24% increase in dementia incidence. In the Fine–Gray model, increased dementia incidence varied from 8–12%.

Based on this, the authors of the study note, “After considering these phenomena, we suggest that symptoms of psychological distress are etiological risk factors for dementia but only weakly increase the incidence of dementia in the presence of competing risk of death.”