Table 1.

Clinicodemographic features of progressive supranuclear palsy (PSP) cases with the SMPD1 variant p.P332R

	Case 1	Case 2	Case 3
Diagnostic classification	PSP-RS*	PSP-RS*	PSP-RS†
Age at symptom onset (yr)	67	60	57
Ancestry; sex	Chinese (Malaysia); female	Chinese (Malaysia); female	Chinese (Singapore); male
Family history	Negative (note: patient was a single child)	Negative	Negative
Main clinical features	Recurrent falls due to imbalance, starting from ~1.5 y after symptom onset; slurred speech; vertical > horizontal supranuclear gaze palsy; mildly impaired cognition	Recurrent falls due to imbalance within 1st year of symptom onset; dragging speech; slowing of up-saccades; cognitive including memory dysfunction; depressive symptoms; insomnia (but no RBD symptoms)	Typical features presenting with recurrent falls (further records N/A as already deceased)
Brain MRI features	Cerebral atrophy; mild hummingbird sign	Unremarkable (but mid-sagittal image not available)	Generalized cerebral atrophy

Case 1 is reported in detail within the text. Diagnosed by ^*S.Y.L. or ^†E.K.T., applying the Movement Disorder Society clinical diagnostic criteria for progressive supranuclear palsy. [1,2]

N/A, not available; PSP-RS, progressive supranuclear palsy, Richardson syndrome subtype; RBD, rapid eye movement sleep behavior disorder; MRI, magnetic resonance imaging.