Table 4

OR for cognitive impairment in 93 men by estimated duration of taking benzodiazepine

Estimated duration of benzodiazepine taking	All dementia	‘Vascular’ dementia	‘Non-vascular’ dementia
Estimated duration of benzodiazepine taking	93 men	44 men	49 men
4 years or less	10 men	4 men	6 men
OR (95% CI), p	4.38 (1.15 to 16.75), 0.03	2.96 (0.25 to 35.71), 0.39	6.61 (1.42 to 30.83), 0.02
>4 years	12 men	8 men	4 men
OR (95% CI), p	2.31 (0.74 to 7.20), 0.15	3.83 (0.86 to 17.11), 0.08	1.86 (0.31 to 10.96), 0.50

ORs have been adjusted for age, social class, education, smoking, alcohol intake, body mass index, angina, IHD, cognitive function (NART, CAMCOG, AH4, MMSE, CRT), distress, anxiety and daytime sleepiness.
NART, National Adult Reading Test; MMSE, Mini-Mental State Examination; CAMCOG, Cambridge Cognitive Examination; CRT, Choice Reaction Time; IHD, Ischaemic Heart Disease.