Demographic characteristics.

***<p>p<0.001 compared with normal controls.</p><p>Abbreviations: AD, Alzheimer's disease; DLB, dementia with Lewy body; AF-GP, the atrophic form of general paresis; NC, normal control.</p

Correlations between CSF CysC and CSF Αβ40 and Αβ42 levels.

<p>Abbreviations: AD, Alzheimer's disease; DLB, dementia with Lewy body; AF-GP, the atrophic form of general paresis; NC, normal control; CysC, cystatin C; Αβ, amyloid-β.</p

The CSF and serum CysC levels in AD, DLB, AF-GP and normal control subjects.

<p>(A) The levels of CSF CysC were significantly lower in patients with AD, DLB and AF-GP compared to normal controls. (B) The levels of serum CysC were significantly lower in patients with AF-GP compared to normal controls. (C) The CSF/serum CysC ratios were significantly lower in patients with AD and DLB compared to normal controls. Statistically significant difference was calculated using one-way ANOVA, followed by Bonferroni's post hoc test. Data are means ± SD. Abbreviations: CysC, cystatin C; AD, Alzheimer's disease; DLB, dementia with Lewy body; AF-GP, the atrophic form of general paresis; NC, normal control. (*p<0.05, **p<0.01, ***p<0.001).</p

Scatter plots of the correlations between CSF CysC and CSF Αβ40 and Αβ42 levels.

<p>(A) (C) (D) The CSF CysC levels were positively correlated with CSF Αβ40 levels in AD (r = 0.312, p = 0.026), AF-GP (r = 0.441, p = 0.003) and normal control (r = 0.388, p = 0.034) subjects. (E) (G) (H) The CSF CysC levels were positively correlated with CSF Αβ42 levels in AD (r = 0.306, p = 0.029), AF-GP (r = 0.657, p<0.001) and normal control (r = 0.507, p = 0.004) subjects. (B) (F) No significant correlations were found between CSF CysC and CSF Αβ40 or Αβ42 in patients with DLB (r = 0.021, p = 0.919, and r = 0.037, p = 0.859, respectively). The correlations of the measured values were examined using the Pearson correlation coefficient. Abbreviations: CysC, cystatin C; Αβ, amyloid-β protein; AD, Alzheimer's disease; DLB, dementia with Lewy body; AF-GP, the atrophic form of general paresis; NC, normal control.</p

The serum and CSF CysC levels of dementia patients divided by CDR scores.

<p>No significant differences in serum or CSF CysC levels were observed in patients with AD (A and D), DLB (B and E) and AF-GP (C and F). Statistically significant difference was calculated using one-way ANOVA. Data are means ± SD. Abbreviations: CysC, cystatin C; CDR, Clinical Dementia Rating Scale; AD, Alzheimer's disease; DLB, dementia with Lewy body; AF-GP, the atrophic form of general paresis.</p

The CSF Αβ40 and Αβ42 levels in AD, DLB, AF-GP and normal control subjects.

<p>(A) The levels of CSFΑβ40 were significantly lower in patients with AD and DLB compared to normal controls. There was a trend towards decreased CSF Αβ40 levels in patients with AF-GP compared to normal controls (p = 0.075). (B) The levels of CSF Αβ42 were significantly lower in patients with AD, DLB and AF-GP compared to normal controls. Statistically significant difference was calculated using one-way ANOVA, followed by Bonferroni's post hoc test. Data are means ± SD. Abbreviations: Αβ, amyloid-β protein; AD, Alzheimer's disease; DLB, dementia with Lewy body; AF-GP, the atrophic form of general paresis; NC, normal control. (**p<0.01, ***p<0.001).</p

Clinical data.

***<p>p<0.001 compared with normal controls.</p><p>Abbreviations: AD, Alzheimer's disease; DLB, dementia with Lewy body; AF-GP, the atrophic form of general paresis; NC, normal control; MMSE, Mini Mental State Examination; MoCA, Montreal Cognitive Assessment; ADAS-cog, Alzheimer's Disease Assessment Scale-cognitive subscale; GDS, Geriatric Depression Scale; NPI, Neuropsychiatric Inventory; CDR, Clinical Dementia Rating Scale; GFR, glomerular filtration rate; na, not applicable.</p