Short duration of focal onset awareness and impaired awareness seizure are characteristic features of epilepsy in elderly patients

Figures & data

Table 1 Clinical information

	Age (years)	Sex	Diagnosis (n, %)	Treatment for epilepsy (n, %)	Outcome (n, %)	Cognitive impairment n=58 (38.24%)	Psychiatric symptoms n=47 (30.9%)	Driving (MVA+/−)	Transient amnesia
Epilepsy n=84	Median 71, SD 6.9	Males – 50, females – 34	TLE (63, 75.0%)	AED (64, 76.2%), cranial surgery (2, 2.3%), VNS (1, 1.2%), WAS (17, 20.2%)	Free (45, 53.6%) ≥80% (23, 27.4%) ≥50 (5, 6.0%), no change (11, 13.1%)	MCI (23, 27.4%), AD (7, 8.33%), DLB (4, 4.8%), VD (3, 3.6%), mixed (2, 2.4%), not examined (45, 53.6%)	n=28, 33.3%, BPSD (9, 32.1%), non-BPSD (19, 67.9%)	n=28 (MVA 8)	TEA: n=4 (4.8%)
			FLE (12, 14.3%) OLE (2, 2.3%) TLE/FLE (1, 1.1%) Epileptic convulsion (5, 6.0%) Focal onset epilepsy (1, 1.2%)
Nonepilepsy n=68	Median 71, SD 7.5	Males – 34, females – 34	Nonepileptic event (39, 58.8%) Syncope (10, 14.7%) BPSD (7, 10.3%) Postprandial hypotension (3, 4.4%) PNES (3, 4.4%) Hypoglycemia (2, 2.9%) PD (2, 2.9%) PHT toxicity (1, 1.4%) TGA (1, 1.4%)		MCI (12, 17.6%), DLB (4, 5.9%), AD (2, 2.9%), VD (1, 1.5%), not examined (49, 72.1%) n=19, 27.9% BPSD (13, 68.4%), non-BPSD (6, 31.6%) n=24 (MVA 2) TGA: n=1 (1.5%)

Abbreviations: AED, antiepilepsy drug; BPSD, behavior psychiatric symptoms of dementia; DLB, dementia of Lewy body; FLE, frontal lobe epilepsy; MCI, mild cognitive impairment; MVA, motor vehicle accident; n, number; OLE, occipital lobe epilepsy; PD, Parkinson’s disease; PHT, phenytoin toxicity; PN, psychogenic nonepileptic symptoms; TEA, transient epileptic amnesia; TGA, transient global amnesia; TLE, temporal lobe epilepsy; VD, vascular dementia; VNS, vagus nerve stimulation; WAS, wait-and-see approach.

Table 2 Conscious level, duration of symptoms and convulsions

Conscious level I
Epilepsy n=6	Nonepilepsy n=14	P<0.028
Motor onset (n=4)	Motor symptom (n=8)
Hand/leg twitching (n=3)
Aphasia with motor (n=1)
Non-motor (n=2)	Non-motor symptom (n=5)
Sensory onset (n=2)
	Motor + sensory (n=1)
Duration
Range: 2–3, median: 2, mean: 2.167, SD: 0.408	Range: 1–6, median: 5.5, mean: 4.857, SD: 1.610	P<0.006
Conscious level II
Epilepsy n=57	Nonepilepsy n=32	P=0.015
Focal impaired awareness	Abnormal behavior
Duration
Range: 1–6, median: 5, mean: 2.09, SD: 1.005	Range: 1–6, median: 5, mean: 4.59, SD: 1.60	P<0.001
Conscious level III
Epilepsy n=22	Nonepilepsy n=28	P=0.075
Duration
Range: 1–5, median: 2.000, mean: 2.045, SD: 0.950	Range: 1–5, median: 2.000, mean: 2.286, SD: 1.560	P=0.748
Convulsions	n=8	P=0.044
n=22

Notes: In consciousness level I, there were 6 patients who exhibited clinical manifestations under wakefulness (3 motor, 2 sensory, and 1 aphasia with motor manifestation) in the epilepsy group while there were 14 patients in the nonepilepsy group. There were more patients in the nonepilepsy group than the epilepsy group (P<0.028). In consciousness level II, there were 57 patients who showed loss of awareness in the epilepsy group and 32 patients who exhibited attention, concentration and performance impairment, etc, in the nonepilepsy group. This difference was statistically significant between the groups (P=0.015). Impaired awareness was more commonly seen in the epilepsy vs the nonepilepsy group. The duration was shorter in the epilepsy vs the nonepilepsy group (P<0.001). In consciousness level III, there were 22 patients in the epilepsy group and 28 patients in nonepilepsy group who lost consciousness. There was no significant difference between these two groups (P=0.075). There was also no statistically significant difference for the duration between the two groups (P=0.748). In terms of convulsion, there were 22 patients in the epilepsy and 8 in the nonepilepsy group who exhibited generalized convulsions. The difference between the groups was statistically significant (P=0.044).

Figure 1 Consciousness level and duration of symptoms.

Notes: The two main components of consciousness are: wakefulness and awareness. In the full wakeful level (level I), there were more patients in the nonepilepsy group (non-Epi G) than the epilepsy group (Epi G). The lack of a definitive description of the aura by elderly might lead to a missed diagnosis. During level II of impaired awareness (level II), there were more patients in the Epi G than the non-Epi G. The duration of the epileptic seizure was <1 minute for both the level I and II levels. Conversely, in elderly patients who exhibited a loss of consciousness, neither the consciousness level nor the duration of symptoms could be used to determine the difference between epilepsy and nonepilepsy. Thus, at this level, convulsions might be the feature that needs to be observed in order to determine Epi G.

Figure 2 Etiology of epilepsy.

Notes: This figure presents the etiology of epilepsy. A total of 61% of these patients exhibited epilepsy of an unknown etiology followed by AD. Lacunar infarction (lacunar), major vessel infarction (major inf), hemorrhagic infarction (hemorrhagic inf), SAH, AVM.
Abbreviations: AD, Alzheimer’s disease; AVM, arteriovenous malformation; SAH, subarachanoid hemorrhage.