Heart Rate Variability: Are We Ignoring a Harbinger of Health

Long ago, tests like the "sed rate" (erythrocyte sedimentation rate) and later, the C-reactive protein (CRP) test, were commonly used to detect infectious or inflammatory diseases. These tests were simple, quick, and cost-effective, offering high sensitivity but low specificity. They could indicate the presence of a disease, but not its specific type.

Heart Rate Variability (HRV) might be emerging as a similar sensitivity indicator, but for nervous system and cardiovascular malfunctions. HRV measures the variation in time between heartbeats and is influenced by the autonomic nervous system. Existing literature links changes in HRV to various conditions, including PTSD, sleep disorders, depression, and cardiac arrhythmias.

With over 100 million Americans using smartwatches or fitness monitors, a significant portion of these devices measure HRV. However, there's a notable gap in credible research on the vast data these wearables collect. While these devices offer insights into HRV, they also caution against using the data for medical purposes, emphasizing the need for further understanding and research.