Affiliations: [a] Amen Clinics, Costa Mesa, CA, USA
| [b]
Thomas Jefferson University School of Medicine, Philadelphia, PA, USA
| [c]
UCLA Medical Center, Los Angeles, CA, USA
| [d]
UCSF Medical Center, San Francisco, CA, USA
Correspondence:
[*]
Correspondence to: Daniel G. Amen, MD, Amen Clinics Inc., Costa Mesa, CA, USA. Tel.: +1 949 266 3771; Fax: +1 949 266 3743; E-mail: [email protected].
Abstract: Background: Depression and cognitive disorders (CDs) are two common co-morbid afflictions that commonly present with overlapping symptoms. Objective: To evaluate if perfusion neuroimaging with brain SPECT can distinguish persons with depression from those with CDs or both conditions. Methods: Inclusion criteria were DSM-IV defined depression or CDs (Alzheimer’s disease, vascular dementia, dementia not otherwise specified, and amnestic disorders not otherwise specified) including persons with both (total n = 4,541; 847 CDs, 3,269 depression, 425 with both). Perfusion differences between the groups were calculated using two-sampled t-tests corrected for multiple comparisons. Diagnostic separation was determined with discriminant analysis. Feature selection revealed predictive regions in delineating depression from CDs and comorbid cases. Results: Persons with CDs had lower cerebral perfusion compared to depression. In co-morbid persons, cerebral hypoperfusion was additive, with regions showing lower regional cerebral blood flow compared to either diagnosis alone. Both baseline and concentration SPECT regions yielded correct classification of 86% and leave one out cross-validation of 83%. AUC analysis for SPECT regions showed 86% accuracy, 80% sensitivity and 75% specificity. Discriminant analysis separated depression and CDs from comorbid cases with correct classification of 90.8% and cross validated accuracy of 88.6%. Area under the curve was 83% with sensitivity of 80% and specificity of 70%. Feature selection identified the most predictive regions in left hippocampus, right insula, cerebellar, and frontal lobe regions. Conclusion: Quantitative perfusion SPECT neuroimaging distinguishes depression from dementia and those with both co-morbidities. Perfusion brain SPECT can be utilized clinically to delineate between these two disorders.
