CU Medicine finds benign prostatic hyperplasia patients suffer from up to five times the risk of urological complications after COVID-19 infection
COVID-19 infection affects many extra-respiratory systems, including the urinary system. The Chinese University of Hong Kong (CUHK)’s Faculty of Medicine (CU Medicine) has conducted analysis using data from around 18,000 benign prostatic hyperplasia (BPH) patients in the local public healthcare system. Results showed that BPH patients infected with COVID-19 suffer from incidence rates of complications 2.9 to 5.31 times those of patients without COVID-19 infection, regardless of COVID-19 severity, among which the relative risk of urinary retention occurrence is the highest, followed by bacteriuria and haematuria. It is the largest cohort study in the world demonstrating that COVID-19 infection is associated with an increased incidence of BPH complications. Details of the study have been published in the Journal of Internal Medicine.
BPH is a common health problem among middle-aged and older men
The prostate is a male sex gland which produces thick fluid that forms part of the semen. BPH is a non-malignant enlargement of the prostate gland, which may gradually progress to a compression of the urethral canal. This causes obstruction of the urethra and interferes with normal urine flow. An international literature shows that prevalence of BPH is more than 80% in males older than 70.
CU Medicine has conducted analysis using data from around 18,000 benign prostatic hyperplasia (BPH) patients in the local public healthcare system. Results showed that BPH patients infected with COVID-19 suffer from higher risk of complications than patients without COVID-19 infection, regardless of COVID-19 severity. Among the complications, the relative risk of urinary retention of the COVID-19 group is 5 times of that of the control subjects. (From left) Dr Jeremy Teoh, Associate Professor, Division of Urology; Professor Ng Chi-fai, Tzu Leung Ho Professor of Urology, Department of Surgery at CU Medicine; and Dr Alex Liu, Resident, Division of Urology, Department of Surgery at the Prince of Wales Hospital.
Professor Ng Chi-fai, Tzu Leung Ho Professor of Urology, Department of Surgery, CU Medicine, said, “BPH affects not only patients’ quality of life, but its complications such as retention of urine, urinary tract infection, haematuria and bladder stone formation can also cause patients’ clinical conditions to deteriorate. Acute hospital care is needed in severe cases. As prostate epithelial cells are known from previous studies to be a target of the COVID-19 virus, we hypothesised that the risk of BPH complications increases in people infected with the virus, and so we conducted this large-scale research.”
Largest cohort study in the world to demonstrate the association between COVID-19 infection and incidence of BPH complications
CU Medicine has conducted the largest cohort study in the world demonstrating COVID-19 infection’s association with the incidence of BPH complications. Its analysis examined data from all BPH patients receiving therapeutic treatment in Hospital Authority hospitals in 2021. 8,993 BPH patients with COVID-19 infection were included in the subject group (COVID-19 group), while the same number of BPH patients without COVID-19 infection were included in the control group. The two groups demonstrated statistically significant differences in incidence rates of complications, with the COVID-19 group showing a higher incidence of urinary retention, haematuria, and urinary tract infection. COVID-19 group also had a much higher incidence of the need for combination therapy, implied worsen of their symptom after the infection. Details can be found in table 1.
Table 1: Comparison of incidence rates of complications and clinical outcomes between BPH patients with and without COVID-19 infection
Incidence rate of complication and clinical outcomes | BPH patients with COVID-19 infection (COVID-19 group, 8,993 patients) | BPH patients without COVID-19 infection (control group, 8,993 patients) | Relative risk of complication in COVID-19 group compared with control group |
Retention of urine | 4.55% | 0.86% | 5.31 |
Haematuria | 1.36% | 0.41% | 3.3 |
Urinary tract infection | 4.31% | 1.49% | 2.9 |
Bacteriuria | 9.02% | 1.97% | 4.58 |
Addition of combination therapy due to clinical condition deterioration | 0.5% | 0.02% | 25 |
Dr Jeremy Teoh says that there was a 70-year-old BPH patient had to be admitted to the hospital due to acute urinary retention after COVID-19 infection. He needed to cut the prostate tissue through surgery in order to resume normal urination.
Professor Ng Chi-fai reminds patients with BPH that if they find symptoms such as difficulty in urinating, frequent urination, or lower abdominal distension and pain worsening after being infected with COVID-19, they should seek medical treatment as soon as possible.
Dr Alex Liu Qinyang, Resident, Division of Urology, Department of Surgery, Prince of Wales Hospital, stated, “It is worth noting that we found no differences in the incidence of urinary retention or haematuria across different COVID-19 severities. This suggests that even patients with asymptomatic or mild COVID-19 infection can still be affected urologically and suffer from BPH complications.”
Dr Alex Liu states that it is known from previous studies that prostate epidermal cells have two important proteins related to COVID-19 infection. Therefore, BPH patients are at an increased risk of urological complications after being infected with the virus.
Instead of COVID-19 severity, older age is correlated to a higher incidence of urological complications. For example, the study showed that the incidence rate of patients aged 90 or above in the COVID-19 group was 5.9%, while that of patients aged between 60 and 69 was 3.4%. Dr Jeremy Teoh Yuen-chun, Associate Professor, Division of Urology, Department of Surgery, CU Medicine, explained, “This study further shows that older BPH patients are more susceptible to the urological complications of COVID-19 than younger patients once infected. We believe that this is due to this benign condition displaying longitudinal progression with age, meaning patients present with enlarging prostate size and worsening symptoms.”
Dr Teoh added, “The higher risk of urological complications in BPH patients with COVID-19 infection represents a significant clinical burden that clinicians and urologists should be aware of.”
