25 OH-Vitamin D Levels in Healthy Swiss Elderly. Results from the Seniorlabor Study.

16.03.2012 / Medina Escobar P, Risch M, Nydegger U, Risch L
25 OH-Vitamin D Levels in Healthy Swiss Elderly. Results from the Seniorlabor Study.

Kurzbeschrieb für Probanden

Vitamin D-Mangel kommt bei Senioren relativ häufig vor. Gesunde Senioren wurden bisher in der Schweiz nur selten untersucht. Diese Analyse untersuchte den Zusammenhang von Alter und Vitamin D-Spiegel und konnte zeigen, dass die Spiegel bei fortgeschrittenem Alter weiter sinken. Zudem zeigte sich, dass Vitamin D-Konzentrationen aufgrund tieferer Sonnenexposition in den Wintermonaten tiefer liegen. Die Resultate dieser Analyse wurden am nationalen Kongress für Labormedizin Swissmedlab, welcher vom 12. – 14. Juni 2012 in Bern stattgefunden hat, vorgestellt.

Kurzbeschrieb für Fachpersonen

Introduction:

The European population is known for lower 25-OH Vitamin D serum levels during winter months, an observation particularly prominent in the elderly.

Methods:

A study (www.seniorlabor.ch) initiated in 2008 (KEK Berne- Study Nr 166/08) has so far recruited over 1400 apparently healthy Caucasian citizens >60 yrs of age. The serum bank derived from 12 h fasting morning blood samples of healthy elderly subjects was used to quantitate 25 OH-Vitamin D levels. Here we report our results obtained with 1030 60 – 94 yrs old (60-69: 434, M/F 244/190, 70-79: 447, 250/197 and > 80: 149, 81/68) subjects. 25 OH-Vitamin D levels were measured using the HPLC assay featuring cutoffs of 30 ug/L (75 nmol/L) as lower limit of sufficiency. We compared the data from the senior labor population with those on file from clinical samples sent for 25 OH-Vitamin D level determination in a 20 to 60 yrs age group.

Results:

We found 20.87% of elderly subjects with normal levels (M: 14.6%, F: 25.87%) whereas insufficient levels, i.e. those diminishing from 30 to 6 ug/L, were seen in 77.49% (M: 83.88%, F: 72.4%) subjects. Severe deficiency, i.e.levels < 6 ug/L, were seen in 1.16% (M: 0.65%, F: 1.56%) of the elderly. When the levels were averaged, we found mean values of 24 ug/L in all subjects (M: 22.7 ug/L, F: 25 ug/L) in the age group 60-69, slightly lower at 22.9 ug/L in the age group 70-79 (M:22.9 ug/L, F:24 ug/L) and falling to 18.7 ug/L in the very old >80 yrs of age (M:18.6 ug/L, F 18.8 ug/L). A seasonal variation revealed lowest levels in spring and highest late in summer. The elderly population had consistently lower 25 OH Vitamin D levels than those retracted from clinical samples on fi le.

Conclusions:

A majority (3/4) of the elderly subjectively healthy Swiss population presents with Vitamin D insufficiency. There is a progressive decline with age, probably due to lower sunlight exposure and deteriorating dietary supply. Vitamin D insufficiency causes a substantial burden of disease (e.g. falls, osteoporosis, cardiovascular, autoimmune and infections disease, neoplasia). Dietary supplementation to reach serum concentrations up to 60 nmol/L is beneficial.