TABLE 2.

Relative risk (95% CI) of sudden cardiac death by quartile (Q) of magnesium intake¹

	Magnesium intake (mg/d)
	Q1	Q2	Q3	Q4	P for trend2
Median magnesium intake (mg/d)	235	281	321	383
No. of cases	124	96	146	139
Person-years	568,020	567,696	567,670	566,412
Age-adjusted model	1.0 (ref)	0.61 (0.47, 0.80)	0.81 (0.64, 1.03)	0.62 (0.48, 0.79)	0.003
Multivariate model 1	1.0 (ref)	0.63 (0.47, 0.86)	0.82 (0.60, 1.13)	0.63 (0.44, 0.91)	0.06
Multivariate model 2	1.0 (ref)	0.64 (0.47, 0.87)	0.85 (0.62, 1.17)	0.66 (0.46, 0.95)	0.09

¹ref, reference. Multivariate model 1 was a Cox proportional hazards model adjusted for age; history of cardiovascular disease (yes or no); total calories; smoking; BMI (in kg/m²; <25, 25–29.9, or ≥30); parental history of myocardial infarction before age 60 y (yes or no); alcohol intake (<0.1, 0.1–14.9, 15–29.9, or ≥30 g/d); physical activity (quintiles of metabolic equivalent task hours/wk); use of postmenopausal hormones, thiazide diuretics, and aspirin >22 d/mo (yes or no); and intakes of long-chain omega-3 fatty acid (% of energy), calcium (mg/d), potassium (mg/d), and vitamin D (IU/d) (all in quartiles). Multivariate model 2 was adjusted as for model 1 plus hypertension, hypercholesterolemia, and diabetes.

²P for linear trend estimated by assigning the median value of plasma magnesium in each quartile and modeling this as a continuous variable in Cox proportional hazards models.