The association between depression, anxiety, and cognitive function in the elderly general population--the Hordaland Health Study.
Biringer E., Mykletun A., Dahl AA., Smith AD., Engedal K., Nygaard HA., Lund A.
OBJECTIVES: To examine the association between depression and/or anxiety and cognitive function in the elderly general population. SUBJECTS: Non-demented participants from the general population (n = 1,930) aged 72-74 years. METHODS: Symptoms and caseness of depression and anxiety disorder were assessed using the Hospital Anxiety and Depression Scale (HADS). Cognitive function was assessed by the Digit Symbol Test (modified version), the Kendrick Object Learning Test, and the 'S'-task from the Controlled Oral Word Association Test. RESULTS: There was a significant association between depression and reduced cognitive function. The inverse association between anxiety and reduced cognitive performance was explained by adjustment for co-morbid depression. The inverse association between depressive symptoms and cognitive function was found to be close to linear, and was also present in the sub-clinical symptom range. Males were more affected cognitively by depressive symptoms than females. CONCLUSION: The inverse association between depression and cognitive function is not only a finding restricted to severely ill patient samples, but it can also be found in the elderly general population.