The mean change in PDCRS frontosubcotical in "ApoE [epsilon]4 carrier/or MAPT H1/H1" group was 2.45 [+ or -] 3.41 points, while in the "ApoE [epsilon]4 carrier and MAPT H1/H1" it was 6.14 [+ or -] 3.13 points (p=0.019).
The mean change in PDCRS total in "ApoE [epsilon]4 carrier/or MAPT H1/H1" group was 4.05 [+ or -] 4.74 points, while in the "ApoE [epsilon]4 carrier and MAPT H1/H1" group, it was 7.8 [+ or -] 3.72 (p=0.031).
There was no statistical significant correlation between duration of illness and both UPDRS and PDCRS, as illustrated in Table 5.
In our study, the mean PDCRS frontosubcortical change was 2.12 points compared to the mean PDCRS posteriorcortical change which was 0.96 points in all patients after 3 months of follow-up.
In the current study, a negative correlation is observed between the age of onset of PD symptoms and PDCRS in group I (r = -0.368, p = 0.195) and Group II (r = -0.188, p = 0.273).
In this study, the decline in cognition after 3 months in Group I patients was 4.14 points (in PDCRS) in relation to worsening of motor symptoms by 1.85 points (in UPDRS III) and in Group II patients where decline in cognition was 2.67 points (in PDCRS) in relation to worsening of motor symptoms by 0.75 points (in UPDRS III); an inverse relationship is observed between UPDRS III (motor) and PDCRS (total), as the UPDRS III score increases (motor symptoms worsen) the PDCRS score decreases (cognitive symptoms worsen).
We also concluded that the changes in PDCRS frontosubcortical, PDCRS posterior-cortical, PDCRS total were worse in the MAPT H1/H1 haplotype compared to other haplotypes as measured by PDCRS without statistical significance.
We found that worsening of cognition was more with ApoE [epsilon]4 carrier than with [epsilon]4 noncarrier where a statistical significance was found between change in PDCRS and ApoE [epsilon]4 carrier/noncarrier as the mean PDCRS total change by 7.43 (in Group I) and 6 (in Group II) points in [epsilon]4 carrier and by 0.86 (in Group I) and 0.29 (in Group II) points in [epsilon]4 noncarrier.
In conclusion, patients in Group I with no cognitive dysfunction showed statistically significant worsening in PDCRS frontosubcortical but not in PDCRS posterior-cortical, while patients in Group II with cognitive dysfunction showed significant worsening in PDCRS frontosubcortical and PDCRS posterior-cortical, and this result of early involvement of the frontosubcortical tests rather than posterior-cortical which is affected later in the disease with development of dementia.
Caption: Figure 5: Group I mean PDCRS change in ApoE [epsilon]4 carrier/noncarrier group.
Caption: Figure 6: Group II mean PDCRS change in ApoE [epsilon]4 carrier/noncarrier.