Late-life depression, subjective cognitive decline, and their additive risk in incidence of dementia: A nationwide longitudinal study

Abstract

Objective Late-life depression and subjective cognitive decline (SCD) are significant risk factors for dementia. However, studies with a large sample size are needed to clarify their independent and combined risks for subsequent dementia. Methods This nationwide population-based cohort study included all individuals aged 66 years who participated in the National Screening Program between 2009 and 2013 (N = 939,099). Subjects were followed from the day they underwent screening to the diagnosis of dementia, death, or the last follow-up day (December 31, 2017). Results Depressive symptom presentation, recent depressive disorder, and SCD independently increased dementia incidence with adjusted hazard ratio (aHR) of 1.286 (95% CI:1.255–1.318), 1.697 (95% CI:1.621–1.776), and 1.748 (95% CI: 689–1.808) respectively. Subjects having both SCD and depression had a higher risk (aHR = 2.466, 95% CI:2.383–2.551) of dementia than having depression (aHR = 1.402, 95% CI:1.364–1.441) or SCD (aHR = 1.748, 95% CI:1.689–1.808) alone. Conclusions Depressive symptoms, depressive disorder, and SCD are independent risk factors for dementia. Co-occurring depression and SCD have an additive effect on the risk of dementia; thus, early intervention and close follow up are necessary for patients with co-occurring SCD and depression.

The impact of social isolation from COVID-19-related public health measures on cognitive function and mental health among older adults: A systematic review and meta-analysis

“…Worsening depression was the most reported symptom (32.76%) compared to other symptoms, which is higher than the previous global estimation of approximately 15% of older adults with depression before the pandemic by WHO ( World Health Organization, 2017 ). Although depressive symptoms and SCD can be seen as independent factors of cognitive decline, co-occurrence of SCD and depression has a combined effect on the risk of dementia ( Jessen et al, 2020 , Wang et al, 2021 ). Clinically, depression often masks and mimics dementia, leading to more complicated care needs and increased caregiver burden.…”

The intricate connection between depression and dementia as a major challenge for clinicians

“…In a prospective study of over 5,500 subjects with normal cognition and 2,500 subjects with MCI at 30 US Alzheimer's Disease Centers, Steenland et al (2012) 46 found that at base line depression was associated in normal individuals as well as in individuals with MCI; a diagnosis of depression within 2 years, but not past depression, was a strong relative risk (RR = 2.35; 95% CI 1.93-3.08) for progression for normal to MCI versus never depressed, and a borderline-significant risk for progression from MCI to AD. More recently, Wang et al (2021) 47 in a nationwide population-based cohort study (n = 939,099 individuals aged 66 years who participated in the South Korea-National Screening Program between 2009 and 2013) found that depressive symptoms, recent depressive disorder and subjective cognition decline (SCD) independently increased dementia incidence with adjusted hazard ratio (aHR) of 1.286 (95% CI: 1.255-1.318), 1.697 (95% CI: 1.621-1.776), and 1.748 (95% CI: 689-1.808) respectively. Results of this study well demonstrate that depressive symptoms and depressive disorder are relevant risk factors for dementia.…”

Subjective cognitive decline and anxious/depressive symptoms during the COVID-19 pandemic: what is the role of stress perception, stress resilience, and β-amyloid?

“…Several studies reported that anxiety, depression, and worries are among the most common concurrent affective symptoms with SCD in older adults [24][25][26]. Moreover, the co-occurrence of SCD with these symptoms has been linked with an increased likelihood of cognitive decline [27][28][29][30][31].…”