Prevalence of vitamin D deficiency in seniors - A retrospective study

Background & aims: Vitamin D deficiency is a condition with different causes. It is associated with numerous comorbidities such as autoimmune diseases, bone diseases, cancer, cardiovascular diseases, neurodegenerative diseases, psychiatric diseases, and respiratory infections like COVID-19. Due to its high prevalence all over the world, it is a major task for health care systems worldwide. Through a combination of low sunlight exposure, insufficient nutrition, and age-related changes in skin, liver, and kidney function, especially seniors and nursing home residents, in particular, have a significantly increased risk of developing a vitamin D deficiency.Methods: This retrospective study analyzed the prevalence of vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] < 12 ng/ml) amongst selected Austrian nursing home seniors. It also examined whether demographic data and other laboratory values like calcium correlate with vitamin D levels by using the Pearson correlation coefficient. This correlation was graphically illustrated with a scatter plot and regression line. A total of 478 patients admitted to a nursing home in Vienna between January 3, 2017, and August 31, 2020, were included.Results: A total of 106 seniors (22,2%) suffered from a manifest vitamin D deficiency. The vitamin D level of the men was significantly lower than the level of the women (22.9 +/- 12.6 ng/ml vs. 26.2 +/- 14.8 ng/ml, p = 0.027). The vitamin D serum levels significantly correlated with the serum calcium levels of the participants (r = 0.19, p < 0.001). 39.5% (189 out of 478) of the nursing home residents had inadequate serum vitamin D levels.Conclusions: In summary, it can be said that the prevalence of vitamin D deficiency among nursing home residents is considerably high. Inadequate vitamin D levels were often associated with reduced calcium levels. Given the high prevalence, the numerous negative health consequences of inadequate levels, and the large therapeutic index, this risk group should get a general supplementation with a dose of 25 mg (1000 IU) vitamin D3 per day. In addition, a blood examination should be performed as early as three months after the start of the supplementation therapy. If some residents do not achieve an adequate vitamin D concentration, the substitution has to be adapted to the individual needs to treat them as precisely as possible.(c) 2023 The Author(s). Published by Elsevier Ltd on behalf of European Society for Clinical Nutrition and Metabolism. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).