biostudies-literatureSluyter JDMedical Research CouncilNational Institute for Health Research (NIHR)e006802https://www.ebi.ac.uk/biostudies/studies/S-EPMC5721873biostudies-literatureUnknown6(10)<h4>Background</h4>The effects of monthly, high-dose, long-term (≥1-year) vitamin D supplementation on central blood pressure (BP) parameters are unknown.<h4>Methods and results</h4>A total of 517 adults (58% male, aged 50-84 years) were recruited into a double-blinded, placebo-controlled trial substudy and randomized to receive, for 1.1 years (median; range: 0.9-1.5 years), either (1) vitamin D₃ 200 000 IU (initial dose) followed 1 month later by monthly 100 000-IU doses (n=256) or (2) placebo monthly (n=261). At baseline (n=517) and follow-up (n=380), suprasystolic oscillometry was undertaken, yielding aortic BP waveforms and hemodynamic parameters. Mean deseasonalized 25-hydroxyvitamin D increased from 66 nmol/L (SD: 24) at baseline to 122 nmol/L (SD: 42) at follow-up in the Journal of the American Heart AssociationEffect of Monthly, High-Dose, Long-Term Vitamin D Supplementation on Central Blood Pressure Parameters: A Randomized Controlled Trial Substudy.PMC5721873G1000143NF-SI-0512-10114Hametner BHughes ADSluyter JDStewart AWScragg RKhaw KTToop LWaayer DParker KHLawes CMMThom SAMWassertheurer SCamargo CAfalseEffect of Monthly, High-Dose, Long-Term Vitamin D Supplementation on Central Blood Pressure Parameters: A Randomized Controlled Trial Substudy.<h4>Background</h4>The effects of monthly, high-dose, long-term (≥1-year) vitamin D supplementation on central blood pressure (BP) parameters are unknown.<h4>Methods and results</h4>A total of 517 adults (58% male, aged 50-84 years) were recruited into a double-blinded, placebo-controlled trial substudy and randomized to receive, for 1.1 years (median; range: 0.9-1.5 years), either (1) vitamin D₃ 200 000 IU (initial dose) followed 1 month later by monthly 100 000-IU doses (n=256) or (2) placebo monthly (n=261). At baseline (n=517) and follow-up (n=380), suprasystolic oscillometry was undertaken, yielding aortic BP waveforms and hemodynamic parameters. Mean deseasonalized 25-hydroxyvitamin D increased from 66 nmol/L (SD: 24) at baseline to 122 nmol/L (SD: 42) at follow-up in the 2017-01-01T00:00:00Z2017 Oct2025-04-05T09:44:48.679Z2019-03-27T03:04:15ZS-EPMC57218732906644410.1161/JAHA.117.006802