Adherence to the Mediterranean diet and its effects on the onset and progression of diabetic nephropathy: a systematic review.
Higher adherence to the Mediterranean diet may reduce the risk of diabetic nephropathy, but current evidence is insufficient to establish causality.
Where it sits
this study against the rest of the liraglutide corpusSummary and findings
This systematic review examined the association between adherence to the Mediterranean diet and the onset and progression of diabetic nephropathy in adults with diabetes or hyperglycemia. Six studies were included, with most showing a lower risk of diabetic nephropathy associated with higher adherence to the diet. However, two studies found no statistically significant associations.
Abstract
Background Diabetic nephropathy (DN) is the primary microvascular complication of diabetes mellitus (DM), contributing to chronic kidney disease, and end-stage renal failure. More than 247,000 individuals develop renal failure due to DM. Mediterranean diet (MD) associated with cardiometabolic benefits and potential renal protective effects, however, its relationship on the onset and progression of DN remains unclear. Objective To examine the association between adherence to the MD and the onset and progression of DN. Methods This systematic review was conducted in accordance with PRISMA 2020 guidelines. A comprehensive search was performed in PUBMED, EBSCO host and SCOPUS databases. Studies including adults with hyperglycemia, DM, or DN, regardless of comorbidities, examining adherence to the MD and renal outcomes. Methodological integrity was evaluated using the Newcastle-Ottawa Scale (NOS) and Jadad Scale. Due to heterogeneity across studies, results were synthesized narratively. Results Six studies met the inclusion criteria. Most studies demonstrated that higher adherence to the MD was associated with a lower risk or odds of DN, particularly among individuals with DM. Reported associations ranged from 21% to 86%, depending on adherence level and study design. Two studies found no statistically significant associations (p > 0.05). Limitations The small number of studies, their predominantly observational design, and geographic concentration limit the generalizability and preclude causal inference. Conclusion Higher adherence to the MD appears to be associated with a lower risk of DN; however, current evidence remains limited and insufficient to draw conclusions regarding causality or disease progression. Further high-quality studies are required.
Background
Diabetic nephropathy is a major complication of diabetes mellitus, leading to chronic kidney disease and end-stage renal failure. With over 247,000 individuals developing renal failure due to diabetes, understanding potential protective dietary factors is crucial. The Mediterranean diet is known for its cardiometabolic benefits, but its specific impact on diabetic nephropathy is not well established.
Methods
This systematic review followed PRISMA 2020 guidelines and included studies from PUBMED, EBSCO host, and SCOPUS databases. It focused on adults with hyperglycemia, diabetes, or diabetic nephropathy, assessing adherence to the Mediterranean diet and renal outcomes. Methodological quality was evaluated using the Newcastle-Ottawa Scale and Jadad Scale, with results synthesized narratively due to study heterogeneity.
Results
Six studies were included, showing a range of 21% to 86% reduction in the risk of diabetic nephropathy with higher adherence to the Mediterranean diet. However, two studies did not find statistically significant associations, with p-values greater than 0.05.
Interpretation
While the review suggests a potential protective effect of the Mediterranean diet against diabetic nephropathy, the evidence is limited by the observational nature of the studies and their geographic concentration. The effect sizes reported are statistically significant but may not be clinically significant without further high-quality research. The findings align with the known cardiometabolic benefits of the Mediterranean diet but require cautious interpretation.
Key findings
- 21% to 86% reduction in risk of DN with higher MD adherence.
- Two studies reported no significant associations (p > 0.05).
- Six studies met inclusion criteria.
- Predominantly observational design.
- Geographic concentration limits generalizability.
Limitations
- small number of studies
- predominantly observational design
- geographic concentration
- limited generalizability
- causal inference precluded