German scientists characterized the features of the cardiovascular system in patients with phenylketonuria

Scientists know that patients with phenylketonuria (PKU) are prone to many cardiovascular risk factors, but so far, their clinical significance has remained unclear. Researchers at the University Medical Center in Berlin found out what disorders are characterized by problems in patients with phenylketonuria.

Phenylketonuria (PKU) is an autosomal recessive congenital metabolic disorder of phenylalanine (Phe) caused by a deficiency of the phenylalanine hydroxylase enzyme. Without treatment, the accumulation of Phe and its metabolites leads to mental retardation and other neurological symptoms. The goal of treating PKU is to reduce the concentration of Phe in the blood. Thus, early diagnosis, usually through newborn screening, and the immediate start of a strict, lifelong low phenylalanine diet are recommended. According to neonatal screening, the frequency of phenylketonuria in Russia is 1: 7000. Previous studies have shown a high prevalence of cardiovascular risk factors in young patients with PKU. Among the risk factors, the most common are dyslipidemia (an imbalance in the good and bad lipoproteins), obesity and hypertension.

German scientists studied the performance of 23 patients with PKU and 28 healthy people of the same age. It turned out that in patients with PKU, the average BMI is outside the normal range in accordance with WHO criteria; In 48% of patients, the weight was within normal limits, 19% were with increased body weight and 33% were obese. BMI was significantly higher compared to healthy people whose average BMI was in the normal range. In addition, patients with PKU had significantly higher systolic and diastolic blood pressure and an increased resting heart rate. Levels of total cholesterol and low density lipoproteins (pro-atherogenic) were significantly increased. The concentration of serum inflammatory response markers was 2-3 times higher in patients with PKU compared with the control group and significantly correlated with BMI, which indicates the effect of increased weight on the patient's inflammatory processes. Arterial stiffness was significantly increased in patients with PKU compared with the control group.

According to scientists, these measurements can detect various vascular changes at an early age and, together with clinical data and selected biochemical markers, improve the assessment of the risk of cardiovascular disease in patients with PKU.

The study was published in the Orphanet Journal of Rare Diseases.