Cysts in kidney may signal stroke risk
Presence of fluid sacs in the kidneys may be indicative of an increased risk of stroke, suggest preliminary data from a study presented at the International Stroke Conference (ISC) 2018 in Los Angeles, California, US.
“This data questions the general consensus that renal cysts are of no clinical significance as they might signal higher degrees of vascular damages in the brain circulation,” said lead author Dr Sanaz Sedaghat from Erasmus University Medical Center in Rotterdam, the Netherlands, who added that renal cysts are common in older people and have generally been regarded as benign.
The population-based study involved 2,984 participants (mean age 71.9 years, 57 percent females) in the Rotterdam Study who underwent a renal ultrasound between 2009–2014. Stroke and transient ischaemic attacks (TIAs) were identified from digital medical records. Seventeen percent of the participants presented with a single cyst and 6.6 percent showed multiple cysts. [ISC 2018, abstract P145 Session A25]
Sedaghat and team found that the more cysts a participant carried, the higher the risk of having stroke. Compared with participants without cyst, participants with a single renal cyst had a 63 percent increased risk of stroke (odds ratio [OR], 1.63, 95 percent confidence interval [CI], 1.01–2.64), while those with multiple renal cysts were more than twice as likely to experience a stroke (OR, 2.14, 95 percent CI, 1.20–3.82).
The associations were independent of known risk factors for stroke such as age, history of cardiovascular disease, high blood pressure, diabetes, and smoking status.
No significant association was found between renal cysts, regardless of single or multiple, and the risk of TIAs (OR, 1.06, 95 percent CI, 0.70–1.59 and 1.29, 95 percent CI, 0.74–2.23, respectively).
According to the researchers, renal cysts usually cause no symptoms and are often discovered during an ultrasound or CT scan that is done for another purpose. Although conventionally considered as benign kidney structural changes, the researchers said recent studies have suggested that renal cysts might be indicative of early-stage kidney damage.
“In this large population-based study, we show that there is a dose-dependent association between renal cysts and prevalent stroke,” said Sedaghat.