Christensen J H, Aarøe J, Knudsen N, Dideriksen K, Kornerup H J, Dyerberg J, Schmidt E B
Department of Endocrinology, Aalborg Hospital, Denmark.
Clin Nephrol. 1998 Feb;49(2):102-6.
Patients with chronic renal failure (CRF) often have autonomic cardiac dysfunction, which can be assessed by measuring heart rate variability (HRV). This dysfunction prediposes the patients to sudden cardiac death. This study describes 24-hour HRV in patients with CRF compared to HRV in patients with a previous myocardial infarction (MI). Furthermore, associations between HRV in patients with CRF and the content of n-3 polyunsaturated fatty acids (PUFA) in cell membranes were examined, because n-3 PUFA may improve HRV. Twenty-nine patients with CRF treated with dialysis were enrolled. A 24-hour Holter recording was obtained at baseline and the HRV variables, RR (= mean of all normal RR intervals during the 24-hour recording) and SDNN (= standard deviation of all normal RR intervals in the entire 24-hour recording) were analyzed. Also, granulocyte fatty acid composition was determined. The patients were allocated to dietary supplementation with either 5.2 g of n-3 PUFA or a placebo oil (olive oil) daily for 12 weeks in a double-blind design. At the end of the supplementation period the Holter recording and blood sampling were repeated. At baseline the CRF patients' mean SDNN ws 86 ms compared to 118 ms (p < 0.01) in patients with a previous MI. After supplementation with either n-3 PUFA or placebo a highly significant correlation was observed between the content of n-3 PUFA in cell membranes and HRV (r = 0.71, p < 0.01). Furthermore, when the patients were dichotomized according to their mean SDNN, it was found, that those with the highest SDNN had a higher content of n-3 PUFA in cell membranes compared to those with the lowest SDNN (7.8% vs 4.2%, p < 0.05). In conclusion, HRV was decreased in CRF patients indicating a cardiovascular autonomic dysfunction. The positive correlation between the n-3 PUFA content in cell membranes and HRV suggests that the effects of an increased intake of n-3 PUFA in CRF patients should be further studied.
慢性肾衰竭（CRF）患者常伴有自主神经心脏功能障碍，可通过测量心率变异性（HRV）进行评估。这种功能障碍使患者易发生心源性猝死。本研究描述了CRF患者的24小时HRV，并与既往有心肌梗死（MI）患者的HRV进行比较。此外，还研究了CRF患者HRV与细胞膜中n-3多不饱和脂肪酸（PUFA）含量之间的关联，因为n-3 PUFA可能改善HRV。招募了29例接受透析治疗的CRF患者。在基线时进行24小时动态心电图记录，并分析HRV变量RR（=24小时记录期间所有正常RR间期的平均值）和SDNN（=整个24小时记录中所有正常RR间期的标准差）。同时，测定粒细胞脂肪酸组成。患者被随机分为两组，采用双盲设计，一组每天补充5.2 g n-3 PUFA，另一组补充安慰剂油（橄榄油），为期12周。在补充期结束时，重复进行动态心电图记录和血液采样。基线时，CRF患者的平均SDNN为86 ms，而既往有MI的患者为118 ms（p<0.01）。补充n-3 PUFA或安慰剂后，观察到细胞膜中n-3 PUFA含量与HRV之间存在高度显著的相关性（r=0.71，p<0.01）。此外，根据患者的平均SDNN进行二分法分析时发现，SDNN最高的患者细胞膜中n-3 PUFA含量高于SDNN最低的患者（7.8%对4.2%，p<0.05）。总之，CRF患者的HRV降低，表明存在心血管自主神经功能障碍。细胞膜中n-3 PUFA含量与HRV之间的正相关表明，应进一步研究增加CRF患者n-3 PUFA摄入量的效果。
