The Prevalence and Determinants of Vitamin D Status among Older Adults: Data from a Longitudinal Aging Study

Abstract

Background: Aging is identified as a risk factor for vitamin D deficiency (VDD) therefore this investigation was designed to determine the prevalence of VDD and its determinants in a sample of older adults. Methods: The data of this study were obtained from the baseline wave of the Longitudinal Aging Study (LAS). Demographic, past medical history, medication history, and smoking behavior were collected using an interview approach. The physical activity and nutritional status of the participants were assessed using a standard questionnaire. Anthropometric indices were measured according to a standard protocol then body mass index (BMI) was calculated. Serum vitamin D and calcium levels were measured by autoanalyzers. Univariate and multiple logistic regression models were applied to detect the associated factors with VDD. Results: Mean age of the participants was 71.82 (SD = 7.63) years. A total of 1319 people participated in our study, and 51.16% (n = 688) were female. A total of 8.42% (n = 111) of the participants had VDD and 17.06% of them (n = 225) had insufficient vitamin D levels. In the multivariable logistic regression model, the age group of 70–79 years in comparison with the age group of 60–69 years had a 43% less chance of VDD. Furthermore, being overweight (OR = 0.36, P = 0.01) and obese (OR = 0.35, P = 0.02), and taking vitamin D supplements (OR = 0.31, P = 0.04) were significantly associated with VDD. Conclusions: Our results showed that 25% of older adults had vitamin D deficiency or insufficiency. In addition, some modifiable lifestyle factors were associated with VDD. Given that, old age is considered a risk factor for VDD. Therefore, detection and improvement of VDD may be a preventive measure in at-risk subjects.

Association between vitamin D status, physical performance, sex, and lifestyle factors: a cross-sectional study of community-dwelling Kosovar adults aged 40 years and older

“…However, it has been shown [ 39 ] that studies providing plausible data on vitamin D status data are lacking for almost two-thirds of low- and middle-income countries (LMICs). Some of these countries reported very high prevalence of vitamin D deficiency, such as 80.1% and 99.6% (< 50 nmol/L and < 75 nmol/L, respectively) in Mongolian women (46.8°N, winter season) [ 40 ], 53.5% in Pakistani men and women combined (< 50 nmol/L, 34.0°N, all seasons) [ 41 ], 54.1% in Iranian women and 46% in men (< 50 nmol/L, 32.4°N, [ 42 ]), and 40.8% in Russian men and women (< 50 nmol/L, 61.5°N, all seasons) [ 43 ].…”