ABSTRACT
BACKGROUND: Patients with end-stage kidney disease on hemodialysis (HD) have an increased risk of death due to the high prevalence of cardiovascular disease. Vascular calcification (VC) is predictive of cardiovascular disease and mortality. We conducted a study to evaluate the prevalence and risk factors for VC in dialysis patients in Qatar. METHODS: This is a retrospective nationwide study including all chronic ambulatory dialysis patients in Qatar from 2020 to 2022. We used our national electronic medical record to track demographics, clinical characteristics, comorbidities, laboratory values, and diagnostic data for each patient. Calcifications were assessed by echocardiography (routinely done for all our dialysis population per national protocol), computed tomography, X-ray, and ultrasound. The study protocol was approved by the local medical research ethics committee (MRC-01-20-377). RESULTS: 842 HD patients were included in this study. Vascular calcifications (VC) were prevalent in 52.6% of patients. The main site of VC was Mitral valve calcifications in 55.5% of patients. Patients with VC were significantly older and had more prevalence of diabetes mellitus (p = 0.001 and p = 0.006, respectively). There was no statistically significant difference between patients with calcifications and patients without calcifications regarding serum calcium, phosphorus, and PTH level. In multivariate analysis, age and diabetes significantly increased the risk factor for calcification (95% CI 1.033-1.065, p < 0.0001, and 95% CI 1.128-2.272, p < 0001, respectively). Moreover, higher vitamin D levels and higher doses of IV Alfacalcidol were significant risk factors for calcifications (95% CI 1.005-1.030, p < 0.007, and 95% CI 1.092-1.270, p < 0.0001, respectively). CONCLUSION: Our study found that vascular calcification was widespread among our dialysis population in Qatar. Implementing the practice of echocardiography in dialysis patients was extremely helpful and the most productive in detecting vascular calcification. Diabetes mellitus almost doubles the risk for vascular calcifications in dialysis patients. These results are beneficial in identifying risk factors for vascular calcification, which can help stratify dialysis patients' risk of cardiovascular disease and optimize prevention efforts.
ABSTRACT
CONTEXT: Patients on maintenance dialysis are more susceptible to COVID-19 and its severe form. We studied the mortality and associated risks of COVID-19 infection in dialysis patients in the state of Qatar. METHODS: This was an observational, analytical, retrospective, nationwide study. We included all adult patients on maintenance dialysis therapy who tested positive for COVID-19 (PCR assay of the nasopharyngeal swab) during the period from February 1, 2020, to July 19, 2020. Our primary outcome was to study the mortality of COVID-19 in dialysis patients in Qatar and risk factors associated with it. Our secondary objectives were to study incidence and severity of COVID-19 in dialysis patients and comparing outcomes between hemodialysis and peritoneal dialysis patients. Patient demographics and clinical features were collected from a national electronic medical record. Univariate Cox regression analysis was performed to evaluate potential risk factors for mortality in our cohort. RESULTS: 76 out of 1064 dialysis patients were diagnosed with COVID-19 (age 56±13.6, 56 hemodialysis and 20 peritoneal dialysis, 56 males). During the study period, 7.1% of all dialysis patients contracted COVID-19. Male dialysis patients had double the incidence of COVID-19 than females (9% versus 4.5% respectively; p<0.01). The most common symptoms on presentation were fever (57.9%), cough (56.6%), and shortness of breath (25%). Pneumonia was diagnosed in 72% of dialysis patients with COVID-19. High severity manifested as 25% of patients requiring admission to the intensive care unit, 18.4% had ARDS, 17.1% required mechanical ventilation, and 14.5% required inotropes. The mean length of hospital stay was 19.2 ± -12 days. Mortality due to COVID-19 among our dialysis cohort was 15%. Univariate Cox regression analysis for risk factors associated with COVID-19-related death in dialysis patients showed significant increases in risks with age (OR 1.077, CI 95%(1.018-1.139), p = 0.01), CHF and COPD (both same OR 8.974, CI 95% (1.039-77.5), p = 0.046), history of DVT (OR 5.762, CI 95% (1.227-27.057), p = 0.026), Atrial fibrillation (OR 7.285, CI 95%(2.029-26.150), p = 0.002), hypoxia (OR: 16.6; CI 95%(3.574-77.715), p = <0.001), ICU admission (HR30.8, CI 95% (3.9-241.2), p = 0.001), Mechanical ventilation (HR 50.07 CI 95% (6.4-391.2)), p<0.001) and using inotropes(HR 19.17, CI 95% (11.57-718.5), p<0.001). In a multivariate analysis, only ICU admission was found to be significantly associated with death [OR = 32.8 (3.5-305.4), p = 0.002)]. CONCLUSION: This is the first study to be conducted at a national level in Qatar exploring COVID-19 in a dialysis population. Dialysis patients had a high incidence of COVID-19 infection and related mortality compared to previous reports of the general population in the state of Qatar (7.1% versus 4% and 15% versus 0.15% respectively). We also observed a strong association between death related to COVID-19 infection in dialysis patients and admission to ICU.