Table 4.

Effect modification of the associations between 10-y mean road traffic noise [per 10 dB(a)] and filled prescriptions for antihypertensive medication.

Covariates	Cases (n)	Most exposed façade		Least exposed façade
		IRR (95% CI)	$p_{\text{interaction}}$	IRR (95% CI)	$p_{\text{interaction}}$
Sex			0.198		0.204
Males	10,425	1.012 (0.985, 1.040)		1.017 (0.983, 1.051)
Females	10,816	0.987 (0.961, 1.014)		0.987 (0.955, 1.020)
Age (y)			0.354		0.193
$<65$	7,606	1.011 (0.980, 1.044)		0.980 (0.941, 1.021)
$\ge 65$	13,635	0.993 (0.969, 1.017)		1.013 (0.983, 1.043)
Education			0.465		0.163
Basic	6,001	1.008 (0.973, 1.045)		1.032 (0.989, 1.078)
Vocational	9,784	1.006 (0.978, 1.034)		0.998 (0.964, 1.033)
Higher	5,456	0.980 (0.944, 1.017)		0.972 (0.928, 1.019)
Smoking status			0.903		0.051
Never	7,325	1.000 (0.968, 1.033)		0.997 (0.958, 1.037)
Former	5,828	0.993 (0.958, 1.030)		0.963 (0.921, 1.006)
Current	8,088	1.004 (0.974, 1.036)		1.033 (0.995, 1.073)
BMI ($\mathrm{kg}/{\mathrm{m}}^2$)			0.374		0.077
Normal and underweight ($<25\mathrm{kg}/{\mathrm{m}}^2$)	8,346	1.002 (0.972, 1.033)		0.984 (0.948, 1.021)
Overweight ($25–30\mathrm{kg}/{\mathrm{m}}^2$)	9,525	0.976 (0.949, 1.004)		0.988 (0.955, 1.023)
Obese ($\ge 30\mathrm{kg}/{\mathrm{m}}^2$)	3,370	1.004 (0.957, 1.053)		1.059 (1.000, 1.122)
Calendar year			0.753		0.902
Before 2005	8,168	0.996 (0.966, 1.027)		1.003 (0.965, 1.043)
After 2005	13,073	1.002 (0.978, 1.027)		1.000 (0.971, 1.030)

Note: Model was adjusted for sex, calendar year, level of education, disposable income, cohabitation, area-level proportion of low income, basic education and unemployment, smoking status, smoking duration, smoking intensity, alcohol intake, abstainers, sport during leisure time (yes/no), sport (hours/week), vegetable intake, and fruit intake. BMI, body mass index; CI, confidence interval; IRR, incidence rate ratio.