Table 1.

Distribution of cases (at diagnosis) with Alzheimer’s dementia and matched^a controls and odds ratios for disease according to residential distance from the high-voltage overhead power grid, Italian deprivation index and residential distance from the high-traffic road network, metropolitan area of Milan, Italy, 2011–2016

		No. of cases (%)	No. of controls (%)	ORb	95% CI
Sex
	Females	6496 (66.05%)	25 984 (66.05%)
	Males	3339 (33.95%)	13 356 (33.95%)
Age group (years)
	66–75	3358 (34.14%)	13 425 (34.13%)
	76 − 85	4943 (50.26%)	19 852 (50.46%)
	>85	1534 (15.60%)	6063 (15.41%)
Deprivation indexc
	1	527 (5.36%)	2051 (5.21%)	1.00	Referent
	2	1364 (13.87%)	5567 (14.15%)	0.95	0.85, 1.07
	3	2859 (29.07%)	11 849 (30.12%)	0.93	0.83, 1.05
	4	3156 (32.09%)	12 425 (31.58%)	0.99	0.89, 1.11
	5	1929 (19.61%)	7448 (18.93%)	1.02	0.91, 1.15
Distance from roads (m)
	<50	704 (7.16%)	2709 (6.89%)	1.05	0.95, 1.15
	50–99	569 (5.79%)	2426 (6.17%)	0.94	0.85, 1.05
	100–199	1227 (12.48%)	4766 (12.11%)	1.04	0.96, 1.12
	200–299	1001 (10.18%)	4002 (10.17%)	1.00	0.93, 1.09
	≥300	6334 (64.40%)	25 437 (64.66%)	1.00	Referent
Distance from power lines (m)
	<50	241 (2.45%)	875 (2.22%)	1.11	0.95, 1.30
	50–199	1076 (10.94%)	4325 (10.99%)	1.00	0.92, 1.09
	200–599	3767 (38.30%)	15 059 (38.28%)	1.01	0.95, 1.07
	≥600	4751 (48.31%)	19 081 (48.50%)	1.00	Referent
Total
		9835 (100.00%)	39 340 (100.00%)

^aEach case was matched with four controls by sex, year of birth, and municipality of residence.

^bOdds ratios and corresponding 95% confidence intervals were calculated from a conditional multivariate logistic model including the distance from the nearest high-voltage overhead power line, the distance from the nearest high-traffic road and the deprivation index as independent variables.

^cThe ‘referent’ level (1) is the least deprived one.

CI, confidence interval; OR, odds ratio.