Perubahan pengambilan garam pemakanan bagi pencegahan dan rawatan penyakit buah pinggang kencing manis
Abstract
Background
There is strong evidence that our current consumption of salt is a major factor for increased blood pressure (BP) and a modest reduction in salt intake lowers BP whether BP levels are normal or raised. Tight control of BP in diabetics lowers the risk of strokes, heart attacks and heart failure and slows the progression of diabetic kidney disease (DKD). Currently there is no consensus in restricting salt intake in diabetic patients.
Objectives
To evaluate the effect of altered salt intake on BP and markers of cardiovascular disease and DKD.
Search methods
In January 2010, we searched the Cochrane Renal Group's Specialised Register, CENTRAL (in The Cochrane Library), MEDLINE (from 1966) and EMBASE (from 1980) to identify appropriate articles.
Selection criteria
We included all randomised controlled trials of salt reduction in individuals with type 1 and type 2 diabetes.
Data collection and analysis
Two authors independently assessed studies and resolved differences by discussion with a third independent author. We calculated mean effect sizes using both the fixed‐effect and random‐effects models.
Main results
Thirteen studies (254 individuals) met our inclusion criteria. These included 75 individuals with type 1 diabetes and 158 individuals with type 2 diabetes. The median reduction in urinary sodium was 203 mmol/24 h (11.9 g/day) in type 1 diabetes and 125 mmol/24 h (7.3 g/day) in type 2 diabetes. The median duration of salt restriction was one week in both type 1 and type 2 diabetes. BP was reduced in both type 1 and type 2 diabetes. In type 1 diabetes (56 individuals), salt restriction reduced BP by ‐7.11/‐3.13 mm Hg (systolic/diastolic); 95% CI: systolic BP (SBP) ‐9.13 to ‐5.10; diastolic BP (DBP) ‐4.28 to ‐1.98). In type 2 diabetes (56 individuals), salt restriction reduced BP by ‐6.90/‐2.87 mm Hg (95% CI: SBP ‐9.84 to ‐3.95; DBP ‐4.39 to ‐1.35). There was a greater reduction in BP in normotensive patients, possibly due to a larger decrease in salt intake in this group.
Authors' conclusions
Although the studies are not extensive, this meta‐analysis shows a large fall in BP with salt restriction, similar to that of single drug therapy. All diabetics should consider reducing salt intake at least to less than 5‐6 g/day in keeping with current recommendations for the general population and may consider lowering salt intake to lower levels, although further studies are needed.
PICOs
Plain language summary
Adakah perubahan pengambilan garam pemakanan membantu dalam pencegahan dan rawatan penyakit buah pinggang kencing manis?
Terdapat bukti kukuh pengambilan garam semasa kita adalah faktor utama dalam peningkatan tekanan darah (BP), samada paras BP adalah normal ataupun tinggi. Kencing manis menjadikannya lebih cenderung untuk mengalami BP yang tinggi, dan ini menambahkan risiko strok, serangan sakit jantung dan mempercepatkan perkembangan penyakit buah pinggang kencing manis. Ulasan ini mendapati 13 kajian yang melibatkan 254 pesakit yang mempunyai kencing manis jenis 1 dan 2. Pengurangan pengambilan garam sebanyak 8.5 g/sehari merendahkan BP sebanyak 7/3 mm Hg. Garis panduan kesihatan awam mengesyorkan pengurangan garam pemakanan kepada kurang dari 5‐6 g/sehari dan pesakit kencing manis akan mendapat manfaat daripada pengurangan garam dalam pemakanan mereka sekurang‐kurangnya kepada paras ini.
