Loss of Nocturnal Dipping in Type 2 Diabetes Mellitus According to Diabetic Kidney Disease: The Role of Vitamin D Levels
Year: 2026
Type: article
Study design: Observational Study
Abstract: Background/Objectives: Abnormal nocturnal dipping (ND) in diabetes mellitus is linked to adverse outcomes. Its association with vitamin D (VD), cardiovascular autonomic neuropathy (CAN), and diabetic kidney disease (DKD) remains unclear. We aim to evaluate the association of VD status with ND loss as well as CAN in type 2 diabetes mellitus (T2DM) across different DKD stages. Methods: 83 T2DM patients were included in this cross-sectional study: 36 with early-stage DKD (urine albumin-to-creatinine ratio [UACR] 30–299 mg/g; Group 1) as well as 47 with advanced-stage DKD (UACR ≥ 300 mg/g; Group 2). Results: Patients with advanced DKD exhibited higher CAN prevalence (72.70% vs. 52.80%; p < 0.05), lower 25(OH)D (26.90 ± 9.90 vs. 29.60 ± 8.00 ng/mL; p = 0.05), and lower systolic ND (0.82 ± 8.40 vs. 4.50 ± 7%; p < 0.05). Among patients with advanced DKD, lower 25(OH)D levels, classified according to the Institute of Medicine (IOM) criteria (normal ≥ 20 ng/mL), were associated with reduced systolic ND (1.90 ± 7.80 vs. −5.60 ± 9.30%; p < 0.05), while the Endocrine Society criteria showed a progressive reduction in systolic ND across VD classification (insufficiency 20–29.9, deficiency <20, and sufficiency ≥30 ng/mL), (−5.60 ± 9.30 vs. −0.20 ± 7.30 vs. 3.30 ± 8%, respectively; p < 0.05). Patients with definite/severe CAN exhibited lower systolic ND (−4.38 ± 7.41 vs. 3.34 ± 8.00%; p < 0.01) than those with absent/early CAN. In addition, lower VD levels were associated with greater CAN severity according to both the Endocrine Society criteria (p < 0.01, r = 0.40), and the IOM criteria (p < 0.05, r = 0.30). In the regression model, VD remained an independent predictor of absence of diastolic ND (Rsqr = 0.393; p < 0.05). Conclusions: These findings suggest a potential link between vitamin D status, autonomic dysfunction, and ND in patients with T2DM and advanced DKD.
Source: Nutrients
DOI: 10.3390/nu18172807
Authors: João Soares Felício, Isabel Jacob Fernandes, Marina Izabel Monteiro de Oliveira, Beatriz Dias Lobo, Maria Eduarda Nunes Avelar do Carmo, Alessandra Pitanga Cardoso Costa, Isabella Almeida Santos, Karem Mileo Felício, Priscila Boaventura Barbosa De Figueiredo, Lilian de Souza D’Albuquerque Silva, Franciane Trindade Cunha de Melo, Ana Carolina Contente Braga de Souza, Márcia Costa dos Santos, Lorena Vilhena De Moraes, Mayana Batista Barros, Paula Gabriella Costa da Penha, Ana Clara Fleury da Fonseca Rodrigues, Fábio Feijó, Pedro Paulo Piani, Valéria Suênya Leal, Melissa de Sá Oliveira dos Reis, Ana Regina Bastos Motta, Natércia Neves Marques De Queiroz
Institution: Universidade Federal do Pará
Language: English
Topic: Vitamin D Research Studies
Subfield: Pathology and Forensic Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,499
OpenAlex ID: W7204452125