1. Collard R.M., Boter H., Schoevers R.A., Oude Voshaar R.C. Prevalence of frailty in community-dwelling older persons: a systematic review. J Am Geriatr Soc. 2012; 60 (8): 1487-1492. doi:10.1111/j.1532-5415.2012.04054.x
2. Bock J.O., Konig H.H., Brenner H., Haefeli W.E., Quinzler R., Matschinger H., et al. Associations of frailty with health care costs–results of the ESTHER cohort study. BMC Health Serv Res. 2016; 16: 128. doi:10.1186/s12913-016-1360-3
3. Fried L.P., Tangen C.M., Walston J., Newman A.B., Hirsch C., Gottdiener J., et al. Cardiovascular Health Study Collaborative Research G Frailty in older adults: evidence for a phenotype. J Gerontol A Biol Sci Med Sci. 2001; 56 (3): M146-156. doi:10.1093/gerona/56.3.m146
4. Bollen S.E., Bass J.J., Fujita S., Wilkinson D., Hewison M., Atherton P.J. The Vitamin D/Vitamin D receptor (VDR) axis in muscle atrophy and sarcopenia. Cellular signalling. 2022; 96: 110355. doi:10.1016/j.cellsig.2022.110355
5. Lelli D., Pérez Bazan L.M., Calle Egusquiza A., Onder G., Morandi A., Ortolani E., et al. 25(OH) vitamin D and functional outcomes in older adults admitted to rehabilitation units: the safari study. Osteoporos Int. 2019; 30 (4): 887-895. doi:10.1007/s00198-019-04845-7
6. Gunton J.E., Girgis C.M., Baldock P.A., Lips P. Bone muscle interactions and vitamin D. Bone. 2015; 80: 89-94. doi:10.1016/j.bone.2015.02.029
7. Yang N., Chang N., Zhang G., Li M., Wu L., Dong W., et al. Analysis of the relationship between frailty index and 25(OH) vitamin D in elderly inpatients. Pakistan journal of pharmaceutical sciences. 2021; 34 (6): 2297-2301
8. Kammeyer A., Luiten R.M. Oxidation events and skin aging. Ageing research reviews. 2015; 21: 16-29. doi:10.1016/j.arr.2015.01.001
9. Marcos-Pérez D., Sánchez-Flores M., Proietti S., Bonassi S., Costa S., Teixeira J.P., et al. Low Vitamin D Levels and Frailty Status in Older Adults: A Systematic Review and Meta-Analysis. Nutrients. 2020; 12 (8): 2286. doi:10.3390/nu12082286
10. Knuuti J., Wijns W., Saraste A., Capodanno D., Barbato E., Funck-Brentano C., et al. ESC Guidelines for the diagnosis and management of chronic coronary syndromes. European heart journal. 2019; 41: 407-477. doi:10.1093/eurheartj/ehz425
11. Ткачева О.Н., Котовская Ю.В., Рунихина Н.К., Фролова Е.В., Наумов А.В., Воробьева Н.М., и др. Клинические рекомендации «Старческая астения». Российский журнал гериатрической медицины. 2025; (1): 6-48. doi:10.37586/2686-8636-1-2025-6-48
12. Schöttker B., Herder C., Rothenbacher D., Perna L., Müller H., Brenner H. Serum 25-hydroxyvitamin D levels and incident diabetes mellitus type 2: a competing risk analysis in a large population-based cohort of older adults. European journal of epidemiology. 2013; 28 (3): 267-275. doi:10.1007/s10654-013-9769-z
13. Liu L., Chen C., Lo K., Huang J., Yu Y., Huang Y., et al. Serum 25-hydroxyvitamin D, frailty, and mortality among the Chinese oldest old: Results from the CLHLS study. Nutrition, metabolism, and cardiovascular diseases: NMCD. 2021; 31 (9): 2707-2715. doi:10.1016/j.numecd.2021.05.033
14. Wang Y., Yan N., Luo Y., Liu K., Wang J., Zhang J., et al. The serum vitamin D levels alleviate the influence of dietary inflammation on frailty: A cross-sectional analysis in the U.S. older adults. PloS one. 2025; 20 (6): e0327251. doi:10.1371/journal.pone.0327251
15. van den Berg K.S., Arts M.H.L., Collard R.M., van den Brink R.H.S., Comijs H.C., Marijnissen R.M., et al. Vitamin D deficiency and course of frailty in a depressed older population. Aging & mental health. 2020; 24 (1): 49-55. doi:10.1080/13607863.2018.1515885
16. Krams T., Cesari M., Guyonnet S., Abellan van Kan G., Cantet C., Vellas B., et al. Is the 25-hydroxy-vitamin D serum concentration a good marker of frailty? J Nutr Health Aging. 2016; 20: 1034-1039. doi:10.1007/s12603-016-0714-1
17. Schoufour J.D., Echteld M.A., Boonstra A., Groothuismink Z.M., Evenhuis H.M. Biochemical measures and frailty in people with intellectual disabilities. Age and ageing. 2016; 45 (1): 142-148. doi:10.1093/ageing/afv152
18. Marcos-Pérez D., Sánchez-Flores M., Proietti S., Bonassi S., Costa S., Teixeira J.P., et al. Low Vitamin D Levels and Frailty Status in Older Adults: A Systematic Review and Meta-Analysis. Nutrients. 2020; 12 (8): 2286. doi:10.3390/nu12082286
19. Vaes A.M.M., Brouwer-Brolsma E.M., Toussaint N., de Regt M., Tieland M., van Loon L.J.C., et al. The association between 25-hydroxyvitamin D concentration, physical performance and frailty status in older adults. European journal of nutrition. 2019; 58 (3): 1173-1181. doi:10.1007/s00394-018-1634-0
20. Xiao Q., Wu M., Cui J., Yuan M., Chen Y., Zeng T. Plasma 25-hydroxyvitamin D level and the risk of frailty among Chinese community-based oldest-old: evidence from the CLHLS study. BMC geriatrics. 2020; 20 (1): 126. doi:10.1186/s12877-020-01523-w
21. Dwimartutie N., Setiati S., Tamin T.Z., Prijanti A.R., Harahap A.R., Purnamasari D., et al. Vitamin D Levels in Pre-frail Older Adults and Its Correlation with Hand Grip Strength. Acta medica Indonesiana. 2023; 55 (2): 172-179
22. Saeki C., Kanai T., Nakano M., Oikawa T., Torisu Y., Saruta M., et al. Low Serum 25-Hydroxyvitamin D Levels Are Related to Frailty and Sarcopenia in Patients with Chronic Liver Disease. Nutrients. 2020; 12 (12): 3810. doi:10.3390/nu12123810
23. Shi Z., Shi K., Zhang Z., Lin J., Fang Y. Mediating Effect of Physical Activity in the Association between Low 25-Hydroxyvitamin D and Frailty Trajectories: The English Longitudinal Study of Ageing. Nutrients. 2022; 14 (11): 2292. doi:10.3390/nu14112292
24. Dai M., Yue J., Zhang J., Wang H., Wu C. Functional dentition is a modifier of the association between vitamin D and the frailty index among Chinese older adults: a population-based longitudinal study. BMC geriatrics. 2022; 22 (1): 159. doi:10.1186/s12877-022-02857-3
25. Gerdhem P., Ringsberg K.A.M., Obrant K.J., Akesson K. Association between 25-hydroxy vitamin D levels, physical activity, muscle strength and fractures in the prospective population-based OPRA Study of Elderly Women. Osteoporos Int. 2005; 16: 1425-1431. doi:10.1007/s00198-005-1860-1
26. Bischoff H.A., Borchers M., Gudat F., Duermueller U., Theiler R., Stähelin H.B., et al. In situ detection of 1,25-dihydroxyvitamin D3 receptor in human skeletal muscle tissue. The Histochemical journal. 2001; 33 (1): 19-24. doi:10.1023/a:1017535728844
27. Dirks-Naylor A.J., Lennon-Edwards S. The effects of vitamin D on skeletal muscle function and cellular signaling. The Journal of steroid biochemistry and molecular biology. 2011; 125 (3-5): 159-168. doi:10.1016/j.jsbmb.2011.03.003