Vitamin D deficiency and course of frailty in a depressed older population

Abstract

Objective: To study the association between vitamin D levels and frailty, its components and course in a depressed sample.

Methods: Baseline and two-year follow-up data from the depressed sample of the Netherlands Study of Depression in Older persons (NESDO), a prospective observational cohort study, were analyzed. The 378 participants (aged 60–93) had a diagnosis of depression according to DSM-IV criteria. Frailty was defined according to Fried’s physical phenotype. 25-OH vitamin D measurement was performed by liquid chromatography – tandem mass spectrometry. Linear and logistic regression analyses were performed, adjusted for covariates.

Results: Higher vitamin D levels were cross-sectionally associated with lower prevalence of frailty (OR 0.64 [95%-CI 0.45 – 0.90], p = .010), predicted a lower incidence of frailty among non-frail depressed patients (OR 0.51 [95%-CI 0.26 – 1.00], p=.050), and, surprisingly, the persistence of frailty among frail depressed patients (OR 2.82 [95%-CI 1.23 – 6.49], p=.015).

Conclusions: In a depressed population, higher vitamin D levels were associated with lower prevalence and incidence of frailty. Future studies should examine whether the favorable effect of low vitamin D levels on the course of frailty can be explained by confounding or whether unknown pathophysiological mechanisms may exert protective effects.

Keywords:

• Vitamin D
• frailty
• depression
• prevalence
• course
• old age

Additional information

Funding

The infrastructure for the Netherlands Study of Depression in Older people is funded through the Fonds NutsOhra, Stichting tot Steun VCVGZ, NARSAD The Brain and Behaviour Research Fund and the participating universities and mental health care organisations (VU University Medical Center, Leiden University Medical Center, University Medical Center Groningen, Radboud University Nijmegen Medical Center, and GGZ inGeest, GGNet, GGZ Nijmegen, and Parnassia). The funding sources had no involvement in the conduction of the study.