One should beware when not getting enough shut-eye: a new study linked shorter sleep duration with a more rapid decline in kidney function.

According to new research headed by Dr. Ciaran Joseph McMullan of Brigham and Women’s Hospital in Boston, kidney function may be compromised with disrupted sleep as many bodily processes follow the circadian clock, or a natural daily rhythm based on regular sleeping and waking cycles.

The researchers analyzed data on 4,238 subjects from the Nurses’ Health Study and found that shorter sleep was significantly connected with a more rapid deterioration in renal function. Women who slept less than five hours per night had a 65 percent increased risk of experiencing this decline compared to those getting seven to eight hours of sleep.

McMullan said that their study is the first to make the link between sleep and renal function. Sleep disruption has been researched expansively in previous studies in cardiovascular and metabolic conditions but not in chronic kidney illness.

“The findings of this paper coupled with research from others suggest that renal physiology may be adversely affected by disruption in sleep, including sleep restriction,” he explained.

McMullan found the results a matter of great concern, as the general American population has been getting less sleep over the last two decades. While they used to sleep eight hours an average per night, the rate has dropped to about 6.5 hours and dipping even more.

It is unclear if sleeping longer improves kidney function or reverses the damage brought about by sleeplessness. More research, according to McMullan, is needed to know how less sleep directly impacts renal decline.

The circadian clock is believed to play a role, as the kidney is programmed to work differently at night than during daytime due to varying demands on the body.

"Maybe short sleep changes the physiology of the kidney over the daily cycle, and these changes might damage the kidney," proposed McMullan.

Poor sleep has been associated with heart disease and other conditions, which makes it possible that the diminished kidney function found in this study could have resulted from health issues affecting the organ, such as hypertension and diabetes.

Thus as more people age and suffer from these medical conditions, kidney diseases will also be on the rise – and too little sleep may be the culprit.

The findings are presented at the American Society of Nephrology Kidney Week from Nov. 3 to 8 in San Diego, California.

Photo: Rachel Calamusa | Flickr