Evaluation of the effect of dipper and nondipper blood pressure patterns on clinical and laboratory data in patients diagnosed with stage 3-4 chronic kidney disease and hypertension

Objective: This study was designed to evaluate and compare the clinical and laboratory findings of patients with dipper and nondipper blood pressure patterns, as assessed by 24-hour ambulatory blood pressure monitoring, among individuals with chronic kidney disease (CKD) and hypertension (HT). Materials and Methods: A total of 213 patients who met the inclusion criteria and were diagnosed with stage 3–4 chronic kidney disease (CKD) and hypertension (HT) between 2020 and 2025 at the Outpatient Clinics of Internal Medicine, Karadeniz Technical University Faculty of Medicine, were enrolled in the study. The included patients were divided into nondipper hypertension (NDHT) and dipper hypertension (DHT) groups based on 24-hour ambulatory blood pressure monitoring (ABPM), and data regarding age, sex, height, body weight, body mass index, laboratory parameters, comorbidities, and the use of antihypertensive drugs were evaluated. This was a single-center, retrospective chart review study. Results: In our study population, nondipper hypertension (NDHT) was detected in 70.4% (n=150) of the patients, while dipper hypertension (DHT) was observed in 29.6% (n=63). Among the NDHT patients, 64.7% (n=97) were male, compared to 69.8% (n=44) of the DHT patients, with no statistically significant difference between the groups (p=0.569). The mean age of NDHT patients was 64.4 ± 14 years, whereas that of DHT patients was 59.6 ± 14.3 years, and the age was significantly lower in the DHT group compared to the NDHT group (p=0.024). The mean body mass index (BMI) was 28.4 ± 4.8 in the NDHT group and 29.1 ± 5.8 in the DHT group, with no statistically significant difference between them (p=0.330). No statistically significant differences were found between NDHT and DHT patients regarding the prevalence of diabetes mellitus (DM), coronary artery disease (CAD), or hyperlipidemia. However, the frequency of cerebrovascular events (CVE) was significantly higher in the NDHT group (p=0.012). When comorbidities were compared between stage 3 and stage 4 CKD groups, the prevalence of congestive heart failure (CHF) was significantly higher in stage 4 CKD patients (p=0.022). Evaluation of hypertensive retinopathy (HTRP) prevalence revealed no significant differences between the NDHT and DHT groups. Similarly, no statistically significant differences were observed between NDHT and DHT groups in terms of the use of antihypertensive drug classes. However, beta-blocker use was significantly more frequent in stage 4 CKD patients compared to stage 3 CKD patients (p=0.037). When laboratory parameters were analyzed, mean hemoglobin, estimated glomerular filtration rate (eGFR) , and 24-hour urinary creatinine clearance (CrCl) levels were significantly lower in NDHT patients. Stage 4 CKD was present in 40% (n=60) of NDHT patients and in 19% (n=12) of DHT patients, with a significantly higher prevalence in the NDHT group (p=0.005). Mean creatinine and parathyroid hormone (PTH) levels were also significantly higher in NDHT patients (p<0.005). No significant differences were found in lipid profile, potassium, sodium, phosphorus, calcium, or albumin values between the groups. Analysis of 24-hour urine samples showed significantly lower sodium excretion in the NDHT group. However, no significant differences were observed in albuminuria or proteinuria levels between NDHT and DHT patients. Conclusion: Our study demonstrates that the nondipper blood pressure pattern may be a risk factor for the progression of chronic kidney disease (CKD) and the development of comorbidities. In particular, the importance of 24-hour ambulatory blood pressure monitoring as a cost-effective, easily accessible, and rapid diagnostic tool has been highlighted. It has been suggested that early identification of the nondipper blood pressure pattern may help prevent progression to end-stage renal disease (ESRD) and reduce the development of comorbid conditions as well as target organ damage. Keywords: Nondipper, Dipper, Chronic kidney disease, Hypertension, 24-hour ambulatory blood pressure measurement