Sex-specific 25-hydroxyvitamin D threshold concentrations for functional outcomes in older adults: PRoject on Optimal VItamin D in Older adults (PROVIDO)
Am J Clin Nutr . 2021 Apr 7;nqab025. doi: 10.1093/ajcn/nqab025
Michelle Shardell 1 2, Anne R Cappola 3, Jack M Guralnik 2, Gregory E Hicks 4, Stephen B Kritchevsky 5, Eleanor M Simonsick 6, Luigi Ferrucci 6, Richard D Semba 7, Nancy Chiles Shaffer 6, Tamara Harris 6, Gudny Eiriksdottir 8, Vilmundur Gudnason 8, Mary Frances Cotch 9, Eric Orwoll 10, Kristine E Ensrud 11, Peggy M Cawthon 12
Items in both categories Women and Seniors are listed here:
- Senior women need slightly more Vitamin D than senior men (24 ng vs 21 ng) – April 2021
- Coronary Artery Disease 2.9 X more likely in postmenopausal women if Vitamin D deficient – March 2020
- Less cognitive decline in women consuming more Magnesium (and vitamins) – Nov 2019
- Dairy improved bones of senior women – if they also had enough vitamin D – Jan 2019
- Metabolic Syndrome 3.5 X more likely if both Vitamin D and Estrogen are low (senior women)– June 2019
- Majority of postmenopausal women have less than 30 ng of Vitamin D - Review June 2019
- Postmenopausal women need Vitamin D, protein and exercise to prevent loss of muscle and bone – Aug 2018
- All older women need vitamin D supplementation to get to even 20 ng (results of modeling) – May 2018
- Half of Women Over 50 Desperately Need This Potent Nutrient (Vitamin D) – April 2018
- Nordic Walking and 4,000 IU of vitamin D lowered cholesterol, fat, weight, and lipids (senior women) – RCT Feb 2018
- Overweight senior women with low vitamin D were 12X more likely to be weak – Feb 2018
- Vitamin D In Older Women - Fractures, Frailty and Mortality – Buchebner thesis 2017
- Metabolic syndrome 1.9 X more likely if senior women had less than 30 ng of Vitamin D – Oct 2017
- Muscle strength of senior women increased 25 percent with vitamin D, decreased 6 percent with placebo – Oct 2016
- Improved muscle function in postmenopausal women with just 1,000 IU of vitamin D daily – RCT May 2015
- Senior Korean women have much less vitamin D than men (possible reasons) Jan 2014
- Metabolic syndrome 2.4 X more likely if senior women had low vitamin D – Nov 2013
- Women very low on vitamin D were 56 percent more likely to die in nursing home – Feb 2012
- Menopause group advises too little vitamin D supplementation etc. – Jan 2012
- Low vitamin D in elderly women associated with being heavier and less active – Jan 2010
- 2X less urinary incontinence in senior women when vitamin D greater than 30 ng– April 2010
Background: Threshold serum 25-hydroxyvitamin D [25(OH)D] concentrations for extraskeletal outcomes are uncertain and could differ from recommendations (20-30 ng/mL) for skeletal health.
Objectives: We aimed to identify and validate sex-specific threshold 25(OH)D concentrations for older adults' physical function.
Methods: Using 5 large prospective, population-based studies-Age, Gene/Environment Susceptibility-Reykjavik (n = 4858, Iceland); Health, Aging, and Body Composition (n = 2494, United States); Invecchiare in Chianti (n = 873, Italy); Osteoporotic Fractures in Men (n = 2301, United States); and Study of Osteoporotic Fractures (n = 5862, United States)-we assessed 16,388 community-dwelling adults (10,376 women, 6012 men) aged ≥65 y. We analyzed 25(OH)D concentrations with the primary outcome (incident slow gait: women <0.8 m/s; men <0.825 m/s) and secondary outcomes (gait speed, incident self-reported mobility, and stair climb impairment) at median 3.0-y follow-up. We identified sex-specific 25(OH)D thresholds that best discriminated incident slow gait using machine learning in training data (2/3 cohort-stratified random sample) and validated using the remaining (validation) data and secondary outcomes.
Results: Mean age in the cohorts ranged from 74.4 to 76.5 y in women and from 73.3 to 76.6 y in men. Overall, 1112/6123 women (18.2%) and 494/3937 men (12.5%) experienced incident slow gait, 1098/7011 women (15.7%) and 474/3962 men (12.0%) experienced incident mobility impairment, and 1044/6941 women (15.0%) and 432/3993 men (10.8%) experienced incident stair climb impairment. Slow gait was best discriminated by 25(OH)D <24.0 ng/mL compared with 25(OH)D ≥24.0 ng/mL in women (RR: 1.29; 95% CI: 1.10, 1.50) and 25(OH)D <21.0 ng/mL compared with 25(OH)D ≥21.0 ng/mL in men (RR: 1.43; 95% CI: 1.01, 2.02). Most associations between 25(OH)D and secondary outcomes were modest; estimates were similar between validation and training datasets.
Conclusions: Empirically identified and validated sex-specific threshold 25(OH)D concentrations for physical function for older adults, 24.0 ng/mL for women and 21.0 ng/mL for men, may inform candidate reference concentrations or the design of vitamin D intervention trials.