Hypomagnesemia in hospitalized horses.

The research paper analyses the prevalence and potential causes of hypomagnesemia, a below-normal level of magnesium in the blood, in horses treated at the North Carolina State University’s veterinary hospital between January 1999 and May 2001. It suggests that certain diseases are associated with a higher incidence of hypomagnesemia and that this condition may influence the duration of hospitalization and mortality in cases of colic.

Rationale and Methodology

• The research was sparked by the need to understand the factors that might be associated with hypomagnesemia — low levels of magnesium in the blood — in horses.
• For this study, the researchers utilized data from horses evaluated at the North Carolina State University, College of Veterinary Medicine’s veterinary teaching hospital between January 1999 and May 2001.
• A nested case-control study was carried out. This form of study is used when researchers wish to investigate a possible association between an outcome and an exposure or factor of interest within a defined cohort.
• The team examined potential relationships between hypomagnesemia and several variables including the characteristics of the horse (signalment), serum chemistry panel, number of hospitalization days, discharge status, and diagnosis.

Findings

• Out of the 823 horses evaluated, 401 or about half exhibited hypomagnesemia. The affected horses had serum total magnesium concentrations below the normal reference range.
• The research shows that hypomagnesemia is more likely to occur in horses who are older than a month.
• Several health conditions, including colic, acute diarrhea, other gastrointestinal diseases, infectious respiratory diseases, and multiorgan system diseases, were found to be associated with hypomagnesemia in adult horses.
• Foals with diarrhea, excluding those with sepsis, were found less likely to have hypomagnesemia.
• No direct relationship was found between hypomagnesemia and overall mortality. However, the study showed that horses with colic that also had hypomagnesemia were less likely to die than those with colic and normal or high total magnesium levels.

Implications

• The study shows that hypomagnesemia is a common condition in hospitalized horses and is associated with a range of health conditions.
• The condition could possibly be used as a diagnostic and even prognostic indicator, particularly in cases of colic.
• The findings also suggest that hypomagnesemia at admission is associated with a longer hospital stay. Further studies could explore why this is the case and how this information could be used to improve horse health and treatment outcomes.