Table 3.

 Association between smoking and AMD causing visual impairment

Risk factor	Controls	Cases	Odds ratio adjusted for age and sex			Odds ratio adjusted for confounders
			OR	95% CI	Wald test	OR	95% CI	Wald test
Never smoked	1698	233	1			1
Ex-smoker	2281	220	1.13	0.88 to 1.44	0.382	1.13	0.86 to 1.47	0.376
Current smoker	378	60	2.33	1.61 to 3.37	<0.001	2.15	1.42 to 3.26	0.001
Never smoked	1698	233	1			1
<20 pack years	1286	143	1.18	0.90 to 1.55	0.214	1.17	0.86 to 1.58	0.303
20–<40 pack years	619	57	1.31	0.90 to 1.92	0.160	1.37	0.93 to 2.01	0.108
40 + pack years	627	59	1.41	0.96 to 2.05	0.075	1.24	0.80 to 1.93	0.336
Never smoked	1602	229	1			1
Stopped 20+ years	1588	140	0.89	0.69 to 1.17	0.399	0.86	0.65 to 1.14	0.295
Stopped 15–<20 years	273	25	1.33	0.85 to 12.08	0.213	1.33	0.82 to 2.14	0.241
Stopped 10–<15 years	223	20	1.42	0.87 to 2.34	0.160	1.41	0.80 to 2.48	0.233
Stopped 5–<10 years	135	16	2.39	1.29 to 5.00	0.015	2.46	1.28 to 4.72	0.008
Stopped <5 years	92	16	2.54	1.55 to 3.20	0.008	2.24	1.01 to 4.96	0.047
Current smoker	388	61	2.37	1.63 to 3.45	<0.001	2.02	1.36 to 2.99	0.001

Data from 4364 controls and 516 cases in the 49 practices taking part in the vision add-on study in the MRC Trial of the Assessment and Management of Older People in the Community. Confidence intervals adjusted for clustered design of the study. Confounders: age (75–79, 80–84, 85–89, and 90+), sex, housing (owner, non-owner, sheltered), body mass index (quintiles), alcohol consumption (never, ex, current below median, current above median), cardiovascular disease (reported heart attack or stroke or angina as assessed by Rose questionnaire), hypertension (reported high blood pressure or current systolic>160 mm Hg or current diastolic >90 mm Hg).