Table 1.

Distribution of demographic characteristics, morbidity status, medication use, and crude matched odds ratios for all injurious road traffic crashes among older adult drivers in Sweden (case–control analysis)

Characteristics	Categories	Casesa (N = 27,096)	Controlsa (N = 108,384)	Crude matched OR
Sex	Male	69.7	69.7	Matched
	Female	30.3	30.3
Age group	50–64 years	69.7	69.7	Matched
	65–80 years	30.3	30.3
Area of residence	North	9.5	9.5	Matched
	Central	43.1	43.1
	South	47.2	47.2
Marital status	Married	55.3	62.9	1.00
	Never married	14.9	14.5	1.17 (1.13–1.22)
	Divorced	23.2	17.5	1.51 (1.46–1.56)
	Widowed	6.3	4.7	1.57 (1.48–1.67)
Occupation	Professional	21.2	23.6	1.00
	Technician	31.7	34.7	1.00 (0.97–1.04)
	Skilled worker	33.2	28.5	1.32 (1.27–1.37)
CCI scoreb	0	96.9	97.8	1.00
	≥1	3.1	2.2	1.44 (1.33–1.56)
Number of different medications dispensedc	0	65.8	68.6	1.00
	1–2	21.4	20.2	1.11 (1.08–1.15)
	3–4	7.4	6.9	1.12 (1.06–1.18)
	≥5	5.5	4.3	1.35 (1.27–1.43)
Benzodiazepinesd	No	95.5	93.6	1.00
	Yes	4.5	3.2	1.34 (1.25–1.43)
Opioid analgesicsd	No	95.8	97.8	1.00
	Yes	4.2	2.2	1.96 (1.82–2.10)
Zolpidem or zopiclone usee	No medications	27.6	31.0	0.93 (0.89–0.97)
	Non-zolpidem or non-zopiclone users (1–2 other medications)	21.7	22.8	1.00
	Non-zolpidem or non-zopiclone users (3–4 other medications)	14.3	14.4	1.05 (1.00–1.10)
	Non-zolpidem or non-zopiclone users (≥5 other medications)	28.6	25.7	1.19 (1.15–1.24)
	Zolpidem only users	3.7	2.8	1.39 (1.28–1.50)
	Zopiclone only users	3.8	3.1	1.33 (1.23–1.43)
	Both zolpidem and zopiclone users	0.4	0.2	1.91 (1.53–2.40)

Data are presented as percentages or as OR (95% confidence interval)

CCI Charlson Comorbidity Index, OR odds ratio

^aTotal might not add up to 100% due to missing data

^bWeighted CCI

^cWithin 1–30 days prior to index date excluding zolpidem, zopiclone, benzodiazepines, opioid analgesics

^dExposure to at least one medication dispensed within 1–30 days prior to the index date

^eWithin 1–180 days prior to index date