CKD is a public health problem that affects > 10% of the general population worldwide (15). ADPKD is the main hereditary cause (16) and is responsible for up to 10% of patients with kidney disease on RRT (10, 17). In Colombia, in 2019, more than 925,996 people with CKD were reported, with a sub estimated prevalence of 1.8%, of which 4.9% had stage 5 CKD (18).
Our study documented an ADPKD period prevalence of 9.81 cases per 100,000 people. This prevalence is far from that reported in the majority of high-income countries, such as in Europe, where the prevalence is 39.6 per 100,000 people (7), or in the US, which has a prevalence of 42.6 per 100,000 people (11). On the other hand, in Colombia, the prevalence of ADPKD among patients who undergo dialysis or kidney transplant was 4.35 cases per 100,000 people, which can be compared with data from other regions. Although it is a much lower value than that reported by the ERA-EDTA Registry on RRT from 12 European countries with 208 million inhabitants for 5-year periods (1991–2010), it shows an increasing ADPKD prevalence from 56.8 to 91.1 per million population (pmp) (4).
In Colombia, every 29 patients out of 1,000 on RRT have ADPKD. This prevalence is comparable to Alves EF et al. that showed a prevalence of 10 per 1,000 patients on hemodialysis. Likewise, in Africa, the frequency in the University Clinic of Nephrology and Hemodialysis of Cotonou was estimated at 18 per 1,000 people (19), and in Taiwan, it was estimated at 19 per 1,000 people on dialysis (20). Moreover, in 2020 in the US, ~ 50 per 1,000 patients were on RRT, 56% were on hemodialysis, 27% were on peritoneal dialysis, and 17% had functional kidney transplantation (21).
The ADPKD patients in Colombia started RRT at an average age of 52.8 years, and these patients were more likely to be women, with ~ 50% on hemodialysis, 18% on peritoneal dialysis and 32% who had kidney transplantation, similar to the US for the same year. For the US, the median age at the start of RRT between 2001 and 2010 was 55.6 years without changes, but RRT was more frequent among males (3). For Europe, the mean age at the start of RRT increased from 56.6 to 58.0 years (p < 0.01) between 1991 and 2010. The increased age at onset of RRT is most likely due to increased access for elderly ADPKD patients or lower competing risks prior to the start of RRT (4).
Our study showed that there is a wide epidemiological variability in the different geographical regions of our country, with a high prevalence in the states and main cities of the periphery, probably related to the effect of georeferenced family clusters and the centralization of RRT in Colombia. This regional difference coincides with observations in other latitudes, where similar studies have been carried out (22, 23). The lowest prevalence was found in Quindío and Caquetá, with 0.57 and 0.08 cases per 100,000 people, respectively. Interestingly, Quindío showed one of the lowest prevalence rates compared to Risaralda, which was the department with the second highest prevalence rate (6.48 cases per 100,000 people). These two departments have minimal geographical separation, and their cultures are similar, but it is likely that migration during the colonial period explains such a markedly different distribution. This hypothesis can be clarified with a genetic study, which allows the description of the prevalence of mutations.
Some strengths of this study is the data based on a nationwide registry with audited medical records, estimated prevalence by states and cities; and in the future, it will allow monitoring and even genotyping to group patients and families according to the risk of disease progression, taking into account the mutational profile and establishing primary and secondary prevention measures and early therapies to prevent progression to dialysis or kidney transplantation (24).
Limitations
Given the secondary source of data, a standardized diagnosis of the disease is lacking. For NRCKD the diagnosis was based on nephrologist clinical judgment. Additionally, we lack information on approximately 3% of the population, which is not affiliated to the health care system.