Clock drawing test as a screening test for dementia in bipolar patients

  • Mr Rodolfo Ladeira, Laboratory of Neuroscience - LIM 27, Institute of Psychiatry, Faculdade de Medicina da Universidade de São Paulo - São Paulo/SP, Brazil
  • Mr Ivan Aprahamian, Laboratory of Neuroscience - LIM 27, Institute of Psychiatry, Faculdade de Medicina da Universidade de São Paulo - São Paulo/SP, Brazil
  • Mrs Monica Yassuda, Universidade de São Paulo - São Paulo/SP, Brazil
  • Mr Breno Diniz, Laboratory of Neuroscience - LIM 27, Institute of Psychiatry, Faculdade de Medicina da Universidade de São Paulo - São Paulo/SP, Brazil
  • Mr Orestes Forlenza, Laboratory of Neuroscience - LIM 27, Institute of Psychiatry, Faculdade de Medicina da Universidade de São Paulo - São Paulo/SP, Brazil
  • Mrs Paula Nunes, Universidade de São Paulo, Brazil

Background: The Clock Drawing Test (CDT) is a useful test for the screening of dementia. The CDT can be negatively affected by mood disorders and there is insufficient evidence of its screening utility for dementia in bipolar patients who have an increased risk for dementia.
Objectives: The study aimed to evaluate if the CDT can be used as a screening test for dementia in bipolar patients.
Methods: The patients were divided into two groups: controls and patients with bipolar disorder. Diagnosis of bipolar disorder was made according to the DSM-IV criteria. Inclusion criteria were: (1) 60 years of age or more; (2) absence of MCI or dementia; (3) subjects currently euthymic in the last month. Ninety-eight patients fulfilled the criteria above (45 controls and 53 bipolar patients). Cognitive state was evaluated with the CAMCOG that yields the MMSE, the Verbal Fluency Test and the CDT. The CDT was additionally scored by Shulman, Mendez, Sunderland and Lessing scales. The two groups were then matched in relation to age, years of schooling and total CAMCOG score, 35 subjects remained in each group.
Results: No difference was found between controls and bipolar patients in all 4 CDT scoring methods: Shulman (4.23 and 4.23 p=1.00), Mendez (19.2 and 19.2 p=0.311), Sunderland (9.7 and 9.5 p=0,353), and Lessing (8.6% and 14.3% p=0,710).
Conclusion: The CDT can be used as a screening test for dementia in euthymic bipolar patients as well as in patients without bipolar disease, a population with increased risk for dementia.