Lower phosphate levels tied to more severe stroke in young people

Young adults with lower serum phosphate levels tend to have more severe stroke compared with their counterparts who have normal phosphate levels, a study reports.

Researchers reviewed the medical records of 687 patients with acute ischaemic stroke and transient ischaemic attack (TIA; mean age 36.8 years) to examine the association between serum phosphate and stroke severity and prognosis.

The primary outcome was 90-day poor functional outcome (modified Rankin Scale score of 2–6), while the secondary outcomes included stroke severity (National Institutes of Health Stroke Scale [NIHSS] ≥5 defined as moderate to severe stroke) and poor functional outcome at hospital discharge.

Results showed that patients with lower serum phosphate levels experienced more severe stoke (p_trend=0.017). The first vs fourth quartile of serum phosphate levels was associated with 85-percent greater odds of having moderate-to-severe stroke (odds ratio [OR], 1.85, 95 percent confidence interval [CI], 1.19–3.22).

In an analysis controlled for confounders other than stroke severity, patients in the first vs fourth quartile of serum phosphate levels had higher odds of poor functional outcome at hospital discharge (OR, 1.74, 95 percent CI, 1.06–2.86) and at the 90-day follow-up (OR, 1.90, 95 percent CI, 1.09–3.31).

However, the association between serum phosphate and poor functional outcomes was attenuated after stroke severity was further adjusted.

The findings indicate that serum phosphate acts as a marker of stroke severity rather than a contributing factor to poor functional outcomes following ischaemic stroke and TIA in young adults.