Impaired awareness may be associated with increased neuropsychiatric symptoms in moderate to severe Alzheimer's disease, but relatively little is known about the association in early Alzheimer's disease. The aim of this study was to investigate if impaired awareness was associated with a higher frequency of neuropsychiatric symptoms in early Alzheimer's disease. In a Danish multicenter study, 321 patients with MMSE score > or =20 were evaluated. Patients with poor insight had significantly more neuropsychiatric symptoms than patients with full insight. When patients had increasing neuropsychiatric symptoms, caregivers reported higher levels of distress.