Increases in pre-hospitalization serum 25(OH)D concentrations are associated with improved 30-day mortality after hospital admission: A cohort study.
BACKGROUND
Pre-hospital vitamin D status may be a modifiable risk factor for all-cause mortality among hospitalized patients.


OBJECTIVE
To examine the association between increases in serum 25-hydroxyvitamin D [25(OH)D] levels during the year before hospitalization and risk of 30-day all-cause mortality after hospital admission.


METHODS
Retrospective cohort study.


METHODS
Two Boston teaching hospitals.


METHODS
We studied 4344 adults hospitalized between 1993 and 2011 who had serum 25(OH)D concentrations measured at least twice within 7-365 days before the index hospitalization.


METHODS
None.


METHODS
The exposure of interest was change in pre-hospital serum 25(OH)D concentrations. The main outcome was 30-day all-cause mortality. We used mixed-effects logistic regression to describe how 30-day mortality differed with changes in pre-hospital 25(OH)D concentrations. Additionally, the odds of 30-day mortality in patients with pre-hospital 25(OH)D increases of ≥10 ng/mL was compared to that of patients with increases of <10 ng/mL.


RESULTS
In a mixed-effect logistic regression model adjusted for age, gender, race, type (medical/surgical), Deyo-Charlson Index, creatinine and hematocrit, 30-day all-cause mortality rate was 8% (95%CI: 1-15) lower for each 10 ng/mL increase in pre-hospital 25(OH)D (P = 0.025) compared with the 30-day all-cause mortality rate in the entire cohort. In an adjusted logistic regression model, absolute changes of ≥10 ng/mL in patients with initial 25(OH)D concentrations < 20 ng/mL (n = 1944) decreased the odds of 30-day all-cause mortality by 48% (adjusted OR 0.52; 95%CI 0.30-0.93; P = 0.026) compared to patients with changes of <10 ng/mL.


CONCLUSIONS
In patients with initial 25(OH)D < 20 ng/mL, subsequent improvements in vitamin D status before hospitalization are associated with decreased odds of 30-day all-cause mortality after hospital admission. A causal relation may not be inferred from this observational study.
Department of Internal Medicine, Division of Endocrinology and Metabolism, Medical University of Graz, Austria.
Karin
K
Amrein
Channing Division of Network Medicine and Pulmonary and Critical Care Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
Augusto A
AA
Litonjua
Department of Medicine, Okinawa Hokubu Prefectural Hospital, Okinawa, Japan.
Takuhiro
T
Moromizato
Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA.
Sadeq A
SA
Quraishi
Pulmonary and Critical Care Medicine, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA.
Fiona K
FK
Gibbons
Department of Internal Medicine, Division of Endocrinology and Metabolism, Medical University of Graz, Austria.
Thomas R
TR
Pieber
Department of Emergency Medicine, Massachusetts General Hospital, Boston, MA, USA.
Carlos A
CA
Camargo
Departments of Nutrition and Epidemiology, Harvard School of Public Health, Boston, MA, USA.
Edward
E
Giovannucci
The Nathan E. Hellman Memorial Laboratory, Renal Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA. Electronic address: kbchristopher@partners.org.
Kenneth B
KB
Christopher
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001900:Boston; D023381:Endpoint Determination; D005260:Female; D017052:Hospital Mortality; D006760:Hospitalization; D006784:Hospitals, Teaching; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D014807:Vitamin D / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000188:drug therapy
D014807:Vitamin D; C104450:25-hydroxyvitamin D
25-Hydroxy vitamin D; Hospitalization; Mortality