Diagnostic accuracy of ¹²³I-FP-CIT (DaTSCAN) in dementia with Lewy bodies: a meta-analysis of published studies

Purpose: A systematic meta-analysis of published studies on the diagnostic accuracy of presynaptic dopaminergic imaging with ¹²³I-FP-CIT (DaTSCAN) in dementia with Lewy bodies (DLB).

Methods: We included (a) studies in which DaTSCAN was performed in cases of diagnostic uncertainty to differentiate between DLB and non-DLB dementia and (b) studies of patients with already established diagnoses of DLB, non-DLB dementia, or normalcy, against which the diagnostic accuracy of DaTSCAN was tested. We applied fixed-effects Mantel-Haenszel and hierarchical logistic regression models for meta-analysis of the diagnostic test's accuracy. The pooled sensitivity, specificity and diagnostic odds ratio (DOR) were estimated. Heterogeneity among studies was estimated by calculating the corresponding I² statistic. We tested for publication or other bias by creating the respective funnel plot.

Results: Four studies, with a total of 419 subjects, were judged to be suitable for meta-analysis. According to hierarchical models, the estimated pooled sensitivity of DaTSCAN in differentiating DLB versus no DLB was 86.5% [95% Confidence Intervals (CI): 72-94.1%], the specificity was 93.6% (95% CI: 88.5-96.6%), and the DOR was 94.2 (95% CI: 25.7-345). The Mantel-Haenszel estimate of overall DOR was calculated at 48.95 (95% CI: 26.16-91.59). There was some heterogeneity among studies (I² = 45%), but this was not found statistically significant (χ² test for heterogeneity p value = 0.142). Funnel plot analysis showed no significant bias.

Conclusion: Allowing for the small number of studies in the meta-analysis, our results showed high diagnostic accuracy of DaTSCAN in DLB diagnosis, especially in terms of specificity.