A frequent treatment recommendation during acute respiratory infection is to increase fluid intake.

The purpose of a study published in Multidisciplinary Respiratory Medicine was to investigate whether upper respiratory tract infections (URTIs), such as common cold, can lead to dehydration—as per the common belief.

This was an exploratory, noninterventional, observational, single-center pilot study, wherein subjects made two visits each, to a UK study center for the assessments of dehydration—once during URTI and then two-to-three weeks later when fully recovered. The primary endpoint was a comparison of serum osmolality during versus after URTI. Complete blood count, serum urea, serum electrolytes, urine parameters, body weight/BMI, subjective assessment of thirst and physician assessment of dehydration were additional outcomes. Only descriptive statistics and shift tables were used.

Overall, 55 adults with moderate-to-severe URTI of < 120 hours in duration were enrolled. There was no evidence of dehydration based on serum osmolality. With only a few exceptions, complete blood count, serum urea, serum electrolytes, urine specific gravity, urine colorand physician ratings of hydration were stable in all participants. Body weight decreased > 1% in 34% of the subjects and increased > 1% in 17% between visits, with similar changes in BMI. On the other hand, urine osmolality varied – 14 subjects showed a decrease and fivre showed an increase, resulting in a higher mean [SD] urine osmolality during URTI. In addition, subjects perceived greater thirst during URTI.

The findings showed no evidence that URTIs, such as common cold, are associated with anincreased risk of dehydration.However, the results do not rule out the potential for dehydration during febrile illness associated with URTIs. Additional studies are needed to confirm these findings and build a body of evidence.

Source: Multidisciplinary Respiratory Medicine. 2019 Oct 31;14:36. doi: 10.1186/s40248-019-0200-9.