Relationship Between Serum Vitamin D Levels and Acute Pneumonia in Children Aged 1–59 Months in Nigeria
Authors: Akeredolu Festus Dele , Akuse R M , Mado S M , Yusuf R 
Published: October 2020

Abstract

Introduction
Acute pneumonia is a leading infectious cause of death among children under 5 years globally and in Nigeria. Despite various existing strategies and interventions, pneumonia mortality remains unacceptably high. Novel interventions like improving vitamin D status may be needed as optimal vitamin D status may facilitate the ability of immune cells to fight against infections like pneumonia. We investigated the relationship between serum vitamin D [25(OH)D] levels and acute pneumonia in children younger than 5 years in Nigeria.

Subjects and methods
This cross-sectional study involved 135 children with pneumonia and 135 apparently healthy controls. Acute pneumonia was diagnosed using the revised World Health Organization criteria (2012) and chest radiological signs. Serum 25(OH)D concentrations were determined using a vitamin D ELISA kit. The mean serum 25(OH)D levels in both groups were compared and also determined odds ratio (OR) of pneumonia.

Results
The mean serum 25(OH)D level of children with pneumonia (52.14 ± 21.87 nmol/l) was significantly lower than that of controls (60.91 ± 32.65 nmol/l), p = 0.010. The proportion of children with low serum vitamin D levels (≤75.0 nmol/l) was significantly higher in the pneumonia group (n = 123, 91.1%) than the control group (n = 97, 71.9%), p &lt; 0.001. After adjusting for confounders, serum 25(OH)D levels of greater than 75 nmol/l was associated with decreased odds of acute pneumonia (adjusted OR = 0.33, p = 0.007).

Conclusion
A low vitamin D level was associated with increased risk of acute pneumonia.
Lay summary

Introduction
Chest infection (pneumonia) is a leading cause of death in children younger than 5 years of age globally and also in Nigeria. Pneumonia death is still very high despite all the existing efforts at reducing it. New methods may still be needed to drastically reduce this problem. One of these new methods may include improving the vitamin D status of an individual because optimal vitamin D levels may help the body to fight against infections like pneumonia. We investigated the relationship between blood levels of vitamin D and pneumonia in children younger than 5 years.

Subjects and methods
Vitamin D levels of 135 children with pneumonia were measured and compared with vitamin D levels of another 135 healthy children without pneumonia. We diagnosed pneumonia by using both revised World Health Organization criteria (2012) and chest X-rays signs. Blood levels of vitamin D were measured using a vitamin D ELISA kit.

Results
The average blood vitamin D level of children with pneumonia (52.14 ± 21.87 nmol/l) was low compared with that of children without pneumonia (60.91 ± 32.65 nmol/l), p = 0.010. The number of children with low blood vitamin D levels (≤75.0 nmol/l) was more in the pneumonia group (n = 123, 91.1%) than in children without pneumonia (n = 97, 71.9%), p &lt; 0.001. After adjusting for other potential risk factors, blood level of vitamin D &gt;75 nmol/l was associated with lower risk of having pneumonia, (adjusted OR = 0.33, p = 0.007).

Conclusion
A low vitamin D level was associated with increased risk of acute pneumonia.