Plasma 25-Hydroxyvitamin D Levels and Risk of Incident Hypertension Among Young Women

Abstract

Abstract-Numerous 5 and various locations in the kidney. 6 -9 Experimental studies demonstrate that 1,25(OH) 2 D inhibits renin expression, 4,10 enhances insulin secretion and sensitivity, 11,12 and blocks proliferation of VSMCs. 13 Although cross-sectional studies demonstrate that 25(OH)D levels, and skin exposure to UVB radiation (the major source of vitamin D), 14,15 are associated with lower blood pressure, 16 -22 prospective data are limited. An interventional study conducted in 148 vitamin D-deficient elderly women demonstrated a 9% decrease in systolic blood pressure with supplemental vitamin D and calcium compared with calcium alone. 23 In a previous prospective study of older women (first Nurses' Health Study) and men (Health Professionals Follow-up Study), we demonstrated an association between deficient levels of 25(OH)D and risk of incident hypertension after adjusting for age, race, body mass index (BMI), and physical activity. However, that study had limited statistical power (190 incident cases), 24 and we did not measure plasma parathyroid hormone (PTH), calcium, or creatinine, factors that are associated with 25(OH)D and that may influence the risk of hypertension. [25][26][27][28] To determine the independent association between plasma 25(OH)D levels and risk of incident hypertension, we conducted a prospective nested case-control study of 1484 young, healthy women from the second Nurses' Health Study. Methods Study PopulationThe Nurses' Health Study 2 is an ongoing prospective cohort study of 116 671 female registered nurses that began in 1989. Participants are followed via biennial questionnaires that gather information on health-related behaviors and medical events. Follow-up of participants was Ͼ90% through 2005. During the years 1997 to 1999, 29 616 participants contributed blood samples that were stored in liquid nitrogen (Ϫ130°C). We conducted a nested case-control study of incident hypertension among those women who contributed blood samples and who did not have prevalent hypertension at the time of blood collection. The institutional review board at Brigham and Women's Hospital reviewed and approved this study.We selected cases and controls from among those who met the following criteria at the time of blood collection: (1) fasting for Ն8 hours; (2) no diagnosis of hypertension; (3) no use of antihypertensive medications; (4) no diagnosis of cancer (except nonmelanoma skin cancer); (5) no diagnosis of either coronary heart disease or diabetes; and (6) BMI Ͻ30 kg/m 2 . This last eligibility criterion is important, because high BMI is a powerful predictor of hypertension 29,30 and of 25(OH)D levels. 22,31 Using risk-set sampling, we selected 750 cases who subsequently developed hypertension and 750 controls who did not develop hypertension. Controls were matched to cases on the following

Serum 25-hydroxyvitamin D and parathyroid hormone levels in relation to blood pressure in a cross-sectional study in older Chinese men

“…One study reported no association between serum 25OHD and future hypertension or change in blood pressure, 17 whereas other studies demonstrated a positive association between plasma 25OHD and risk of developing hypertension. 36,37 The lack of association between vitamin D status and blood pressure might be attributable to the relatively high baseline levels of serum 25OHD among the participants in these studies, as in our study. 18 To our knowledge, only one study has been conducted to examine the association between plasma 25OHD and blood pressure in Chinese.…”

Dietary and Lifestyle Factors and Medical Conditions Associated with Urinary Citrate Excretion

“…History of kidney stones, hypertension, diabetes mellitus, gout, or thiazide use was obtained from the biennial questionnaires. The validity of self-reported history of kidney stones, hypertension, diabetes mellitus, and gout has been documented previously (24)(25)(26)(27)(28)(29)(30)(31).…”

Association Between Elevated Serum Uric Acid and Vitamin D Insufficiency Among the Middle-Aged and Elderly Population

“…In a nested case-control study, in which basal 25(OH) vitamin D and development of incident hypertension were investigated, Forman et al (16) found that among women who developed hypertension, serum uric acid and PTH were higher and 25(OH) vitamin D levels were lower compared with those women who remained normotensive. The latter two studies only recruited women.…”