Table 4.

Association of Calcium and Vitamin D Supplementation With Measures of Depression at Year 3, According to Vitamin D and Calcium Intake at Baseline, Women’s Health Initiative Calcium and Vitamin D Trial, 1995–2003

	Depressive Symptoms (Burnam Score ≥0.06)				Use of Antidepressant Medication
	No. of Cases	Total No.	ORa for Supplementation vs. Placebo	95% CI	No. of Users	Total No.	ORa for Supplementation vs. Placebo	95% CI
Total vitamin D intake, IU/dayb
<100	46	418	0.61	0.30, 1.22	350	4,965	0.89	0.68, 1.16
100–<200	49	487	2.84	1.38, 5.83	550	7,570	1.20	0.96, 1.49
200–<400	34	390	1.80	0.82, 3.97	509	6,382	0.96	0.76, 1.21
400–<600	53	520	0.91	0.49, 1.70	683	8,018	0.92	0.76, 1.13
≥600	37	379	0.99	0.47, 2.05	574	6,468	1.09	0.87, 1.36
Pinteraction				0.03				0.32
Dietary vitamin D intake, IU/day
<100	70	687	0.88	0.51, 1.52	668	8,989	0.91	0.75, 1.11
100–<200	76	876	1.46	0.87, 2.44	1,127	14,039	1.10	0.94, 1.28
200–<400	59	529	1.39	0.76, 2.53	725	8,782	0.96	0.79, 1.17
≥400	14	102	0.99	0.29, 3.35	146	1,593	1.13	0.73, 1.76
Pinteraction				0.55				0.45
Supplemental vitamin D intake, IU/day
None	127	1,201	1.38	0.91, 2.07	1,296	17,367	1.02	0.89, 1.18
<400	20	207	1.15	0.43, 3.11	272	3,383	1.04	0.76, 1.43
400–<800	68	733	1.04	0.61, 1.78	1,038	11,882	0.99	0.84, 1.17
≥800	4	53	0.22	0.02, 2.63	60	771	0.86	0.44, 1.69
Pinteraction				0.48				0.96
Total calcium intake, mg/dayb
<400	29	221	0.50	0.20, 1.24	146	2,358	0.87	0.58, 1.31
400–<800	65	655	1.76	0.98, 3.17	661	8,831	1.00	0.82, 1.22
800–<1,000	24	293	1.81	0.73, 4.48	403	4,682	1.24	0.96, 1.61
1,000–<1,200	19	244	1.16	0.43, 3.19	301	4,154	0.98	0.73, 1.32
≥1,200	82	781	1.05	0.63, 1.73	1,155	13,378	0.97	0.83, 1.14
Pinteraction				0.18				0.52
Dietary calcium intake, mg/day
<400	39	380	0.61	0.29, 1.29	318	4,429	0.94	0.71, 1.25
400–<800	96	932	1.28	0.80, 2.04	1,098	14,298	0.98	0.84, 1.14
800–<1,000	24	328	2.57	1.01, 6.55	450	5,448	1.15	0.90, 1.47
1,000–<1,200	24	231	1.03	0.41, 2.60	270	3,526	1.26	0.92, 1.73
≥1,200	36	323	1.27	0.59, 2.73	530	5,702	0.90	0.71, 1.13
Pinteraction				0.21				0.37
Supplemental calcium intake, mg/day
None	114	1,024	1.28	0.83, 1.99	1,070	14,334	1.00	0.85, 1.17
<400	47	528	1.47	0.77, 2.82	697	7,987	1.13	0.92, 1.38
400–<800	29	382	0.97	0.43, 2.19	516	6,342	0.93	0.74, 1.17
≥800	29	260	0.80	0.34, 1.88	383	4,740	0.96	0.74, 1.26
Pinteraction				0.66				0.63

Abbreviations: AD, antidepressant; CI, confidence interval; OR, odds ratio.

^aMultivariable models adjusted for age, race/ethnicity, WHI Hormone Trial intervention, and WHI Dietary Modification Trial intervention. The analysis of risk of depressive symptoms above the threshold level (Burnam score ≥0.06) included adjustment for this variable at year 1. The analysis of risk of antidepressant use included adjustment for antidepressant use at year 1.

^bTotal nutrient intake = dietary nutrient intake (assessed at year 0) + supplemental nutrient intake (assessed at year 1).