# Dysmagnesemia Incidence in Hospitalized Dogs and Cats: A Retrospective Study

## TL;DR

This study found that low magnesium levels are common in hospitalized dogs but not linked to worse outcomes, while high magnesium levels in cats are rare but more deadly.

## Contribution

The study is the first to focus on ionized magnesium levels in hospitalized dogs and cats, revealing species-specific clinical implications.

## Key findings

- Hypomagnesemia occurred in 35.5% of dogs but did not increase mortality or hospitalization time.
- Hypermagnesemia in cats was rare (8%) but associated with a 2.3 times higher mortality rate.
- Neurological, neoplastic, and endocrine diseases were most linked to hypomagnesemia in dogs.

## Abstract

Few studies have investigated magnesium disorders in veterinary medicine, and most have focused on total magnesium. The aim of the present study was to assess the incidence of dysmagnesemia in hospitalized dogs and cats by focusing on the ionized fraction, which is the biologically active form. Our results showed that hypomagnesemia was common in dogs, even if it was not associated with increased mortality or prolonged hospitalization. In contrast, magnesium disorders were uncommon in cats; however, when hypermagnesemia occurred, the mortality rate increased.

Magnesium plays a vital role in the body. This retrospective study aimed to evaluate dysmagnesemia incidence in hospitalized patients. Medical records of 430 dogs and 310 cats were reviewed, including patients with at least one venous blood gas analysis upon admission. Normal ionized magnesium values were considered 0.5–1 mmol/L for both species, according to the machine range. Data collected included patient demographics, hospitalization details, and outcome. In dogs, hypomagnesemia occurred in 35.5%, hypermagnesemia in 1.1%, and normomagnesemia in 62.2%. No survival differences were observed, but males showed a higher hypomagnesemia incidence. Neurological (51%), neoplastic (50%), and endocrine (42%) diseases were most associated with hypomagnesemia. In cats, hypomagnesemia was found in 6.8%, hypermagnesemia in 8%, and normomagnesemia in 85.2%. Hypermagnesemic cats had 2.3 times higher mortality. Endocrine (28.6%), systemic (13.6%), and urinary (12.9%) disorders had a higher incidence of hypermagnesemia. Dysmagnesemia was not linked to hospitalization length or blood pressure changes. In conclusion, dogs showed a high incidence of hypomagnesemia that was not associated with increased mortality. In contrast, although hypermagnesemia had a low incidence in cats, it was associated with increased mortality.