On-admission serum 25(OH)D level and mortality within one year in older patients

Mounting evidence suggests that vitamin D deficiency is associated with a higher risk of many chronic non-skeletal, age-associated diseases as well as mortality.

To determine, in older patients aged ≥ 80, the prevalence of vitamin D deficiency and its association with comorbidity, laboratory tests, length of stay and mortality within one year from blood withdrawal on admission to acute geriatrics ward.

We retrospectively surveyed electronic hospital health records of 830 older patients. The recorded data included patient demographics (e.g., age, sex, stay duration, readmissions number, death within one year from blood withdrawal on admission), medical diagnoses, laboratory results, including 25-hydroxyvitamin D [25(OH)D], and medications. We compared the characteristics of the patients who survived to those who died within one year.

On admission, in 53.6% patients, vitamin D levels were lower than 50 nmol/L, and in 32%, the levels were ≤ 35 nmol/L. Persons who died were likely to be older, of male sex, were likely to be admitted for pneumonia or CHF, were likely to have lower level of albumin or hemoglobin, lower level of vitamin D or higher vitamin B12 and higher level of creatinine, were also likely to have had a lengthier hospitalization stay, a greater number of hospitalizations in the last year, a higher number of comorbidities, to have consumption of ≥5 drugs or likely to being treated with insulin, diuretics, antipsychotics, anticoagulants or benzodiazepines. Higher age, male sex, on-admission CHF, higher number of drugs, lower albumin, higher vitamin B12, vitamin D < 50 nmol/L, and consumption of antipsychotics and anticoagulants - were predictors of mortality.

Hypovitaminosis D is predictive of mortality in older patients within one year from hospitalization in the acute geriatric ward, but a causal relationship cannot be deduced. Nevertheless, older patients in acute care settings, because of their health vulnerability, should be considered for vitamin D testing. In the acutely ill patients, early intervention with vitamin D might improve outcomes. Accurate evaluation of mortality predictors in this age group patients may be more challenging and require variables that were not included in our study.