Table 4.

Cognitive indices in clinical frontotemporal degeneration (FTD) subtypes, stratified by exposure to TBI-ext^a.

Cognition Z scores		bvFTD	nb	P	PNFA	nb	P	SD	nb	P
MMSE	−TBI	−6.491	581	.113	−6.989	125	.640	−8.804	115	.901
	+TBI	−4.435	25		−5.518	5		−−8.352	10
Logical memory IA	−TBI	−1.818	491	.289	−1.866	96	.859	−2.626	85	.845
	+TBI	−1.524	23		−1.752	4		−2.702	6
Logical memory IIA	−TBI	−1.642	487	.176	−1.358	91	.720	−2.185	83	.539
	+TBI	−1.306	23		−1.149	4		−2.383	6
Forward digit span	−TBI	−1.200	520	.182	−2.280	103	.988	−1.443	98	.869
	+TBI	−0.790	23		−2.292	5		−1.551	9
Reverse digit span	−TBI	−1.362	515	.021	−1.689	100	.368	−0.999	95	.434
	+TBI	−0.709	23		−2.278	4		−1.377	9
Category fluency-animals	−TBI	−2.168	515	.064	−2.208	106	.595	−2.964	103	.635
	+TBI	−1.703	24		−2.491	5		−2.827	9
Category fluency-vegetables	−TBI	−1.598	497	.398	−1.260	100	.724	−2.151	86	.929
	+TBI	−1.390	23		−1.456	5		−2.106	6
Boston naming test	−TBI	−2.738	503	.330	−3.021	101	.301	−7.226	92	.177
	+TBI	−2.134	23		−1.605	5		−8.457	6
Trail making test Part A	−TBI	−2.688	458	.852	−2.588	100	.546	−1.751	91	.552
	+TBI	−2.808	22		−3.388	5		−1.143	6
Trail making test Part B	−TBI	−2.301	347	.142	−2.802	86	.803	−1.521	79	.561
	+TBI	−1.574	18		−2.578	5		−1.982	6
WAIS-R digit symbol	−TBI	−1.799	441	.667	−1.684	99	.714	−0.924	86	.948
	+TBI	−1.947	21		−1.929	5		−0.963	6

Behavioral variant frontotemporal dementia (bvFTD); progressive nonfluent aphasia (PNFA); semantic dementia (SD)

^aTBI-ext: remote traumatic brain injury without chronic neurologic deficit with extended LOC (≥ 5 minutes). Patients with recent TBI or TBI that resulted in chronic neurologic deficit were excluded;

^bIsolated test data were missing from a small proportion of participants; For cognitive Z scores, higher scores represent better performance.