Vitamin D Supplementation And Varicella Zoster Virus Vaccine Responsiveness In Older Long-Term Care Residents

Objectives

1. To determine the increase in Varicella-zoster virus (VZV)-specific cell-mediated immune
response from pre-zoster vaccination to 3 weeks post-vaccination in nursing home
residents after 4 months of high dose vs. standard dose vitamin D3 supplementation.

2. In the same participants as Aim 1, to measure the association between pre-zoster
vaccination 25-hydroxyvitamin D [25(OH)D] levels and the increase in VZV-specific
cell-mediated immune response from pre- vaccination to 3 weeks post-vaccination.

3. Characterize the phenotypic and functional VZV-specific T cell responses to Zostavax,
including memory, effector, Th1/Th2, and homing receptor-bearing T cells in the high
compared to low ELISPOT responders.

Hypotheses

1. At baseline, higher serum 25(OH)D levels will be associated with higher levels of
VZV-specific cell-mediated immunity (cross-sectional).

2. At baseline, higher serum 25(OH)D levels, independent of vitamin D supplementation dose,
will be associated with greater increases in VZV-specific cell-mediated immune responses
to Zostavax, as measured by the interferon (IFN)-γ ELISPOT assay.

3. Compared to standard dose, high dose vitamin D3 supplementation will enhance
VZV-specific cell-mediated immune response to vaccination independent of baseline serum
25(OH)D levels.

Inclusion Criteria:

1. Aged ≥ 60 years;

2. Residing in a long-term care facility;

3. Have not yet received VZV vaccine

Exclusion Criteria:

1. terminal illness (expected survival <6 months);

2. anticipated discharge within 12 months;

3. unable to take whole or crushed tablets;

4. active cancer, except squamous/basal cell carcinoma;

5. severe malnutrition (body mass index <18 kg/m2);

6. current immunosuppressive medications (including corticosteroids);

7. renal failure (eGFR<15 mL/min/1.73m2);

8. currently taking >800 IU/d vitamin D supplementation;

9. history (or strong family history) of kidney stones;

10. history of sarcoidosis or other granulomatous disorders associated with hypercalcemia;

11. elevated baseline hypercalcemia (albumin-adjusted serum calcium >10.5 mg/dL);

12. serum 25 (OH)D level ≥40 ngl/ml at baseline;

13. inability to provide informed consent and no available healthcare proxy;

14. inability of participant or proxy to speak/understand English.

15. previous receipt of the Zostavax (anticipate <10% of trial;

16. known allergy to gelatin, neomycin, or any other component of the vaccine.