Summary: Background and objectives: Adherence to a Mediterranean diet may link to a better preserved kidney function in the community as well as a favorable cardiometabolic profile and reduced mortality risk in individuals with manifest CKD. Design, setting, participants, & measurements: Dietary habits were determined by 7-day dietary records in a population-based cohort of 1110 Swedish men (age 70 years) from 1991 to 1995, 506 of whom were considered to have CKD because of a GFR<60 ml/min per 1.73 m². A Mediterranean Diet Score was calculated, and participants were categorized as having low, medium, or high adherence. Adequate dietary reporters were identified with Goldberg cutoffs (n=597). Deaths were registered during a median follow-up of 9.9 years. Results: Compared with low adherents, medium and high adherents were 23% and 42% less likely to have CKD, respectively (adjusted odds ratio [95% confidence interval]=0.77 [0.57 to 1.05] and 0.58 [0.38 to 0.87], respectively, P for trend=0.04). Among those individuals with CKD, phosphate intake and net endogenous acid production were progressively lower across increasing adherence groups. No differences were observed regarding other cardiometabolic risk factors across adherence groups. As many as 168 (33%) CKD individuals died during follow-up. Compared with low adherents, proportional hazards regression associated medium and high adherents to a 25% and 23% lower mortality risk, respectively (adjusted hazard ratio [95% confidence interval]=0.75 [0.52 to 1.06] and 0.77 [0.44 to 1.36], respectively, P for trend=0.10). Sensitivity analyses showed significant and stronger associations when only adequate dietary reporters were considered. Conclusions: Adherence to a Mediterranean dietary pattern is associated with lower likelihood of CKD in elderly men. A greater adherence to this diet independently predicted survival in those patients with manifest CKD. Clinical trials are warranted to test the hypothesis that following such a diet could improve outcomes (independent of other healthy lifestyles) in CKD patients.

In the United States population, high dietary fiber intake has been associated with a lower risk of inflammation and mortality in individuals with kidney dysfunction. This study aimed to expand such findings to a Northern European population. Dietary fiber intake was calculated from 7-day dietary records in 1110 participants aged 70-71 years from the Uppsala Longitudinal Study of Adult Men (examinations performed during 1991-1995). Dietary fiber was adjusted for total energy intake by the residual method. Renal function was estimated from the concentration of serum cystatin C, and deaths were registered prospectively during a median follow-up of 10.0 years. Dietary fiber independently and directly associated with eGFR (adjusted difference, 2.6 ml/min per 1.73 m(2) per 10 g/d higher; 95% confidence interval [95% CI], 0.3 to 4.9). The odds of C-reactive protein >3 mg/L were lower (linear trend, P=0.002) with higher fiber quartiles. During follow-up, 300 participants died (incidence rate of 2.87 per 100 person-years at risk). Multiplicative interactions were observed between dietary fiber intake and kidney dysfunction in the prediction of mortality. Higher dietary fiber was associated with lower mortality in unadjusted analysis. These associations were stronger in participants with kidney dysfunction (eGFR<60 ml/min per 1.73 m(2)) (hazard ratio [HR], 0.58; 95% CI, 0.35 to 0.98) than in those without (HR, 1.30; 95% CI, 0.76 to 2.22; P value for interaction, P=0.04), and were mainly explained by a lower incidence of cancer-related deaths (0.25; 95% CI, 0.10 to 0.65) in individuals with kidney dysfunction versus individuals with an eGFR≥60 ml/min per 1.73 m(2) (1.61; 95% CI, 0.69 to 3.74; P value for interaction, P=0.01). High dietary fiber was associated with better kidney function and lower inflammation in community-dwelling elderly men from Sweden. High dietary fiber was also associated with lower (cancer) mortality risk, especially in individuals with kidney dysfunction.

Background and objectives Insulin resistance participates in the pathogenesis of multiple metabolic and cardiovascular diseases. CKD patients have impaired insulin sensitivity, but the clinical correlates and outcome associations of impaired insulin sensitivity in this vulnerable population are not well defined. Design, setting, participants, & measurements The prospective cohort study was from the third examination cycle of the Uppsala Longitudinal Study of Adult Men, a population-based survey of elderly men ages 70–71 years; insulin sensitivity was assessed by glucose disposal rate as measured with euglycemic clamps. Inclusion criterion was eGFR<60 ml/min per 1.73 m² (n=543). Exclusion criteria were incomplete data on euglycemic clamp and diabetes (n=97), leaving 446 men with CKD stages 3 and 4 (eGFR median=51.9 ml/min per 1.73 m²; range=20.2–59.5 ml/min per 1.73 m²). Results The mean of glucose disposal rate was 5.4±1.9 mg/kg per minute. In multivariable analysis, the independent clinical correlates of glucose disposal rate were eGFR (slope, 0.02; 95% confidence interval, 0.01 to 0.04), hypertension (−0.48; 95% confidence interval, −0.86 to −0.11), hyperlipidemia (−0.51; 95% confidence interval, −0.84 to −0.18), and body mass index (−0.32; 95% confidence interval, −0.37 to −0.27). During follow-up (median=10.0 years; interquartile range=8.7–11.0 years), 149 participants died. In Cox regression models, glucose disposal rate was not associated with all-cause or cardiovascular mortality. Multiplicative interactions (P<0.05) were observed between glucose disposal rate and physical activity or smoking in total mortality association. After subsequent stratification, glucose disposal rate was an independent correlate of all-cause mortality in smokers (adjusted hazard ratio, 0.72; 95% confidence interval, 0.54 to 0.96 per 1 mg/kg per minute glucose disposal rate increase) and physically inactive individuals (hazard ratio, 0.77; 95% confidence interval, 0.61 to 0.97) but not their counterparts. Conclusion eGFR, together with various components of the metabolic syndrome, contributed to explain the variance of insulin sensitivity in men with CKD stages 3 and 4. Insulin sensitivity was associated with a lower mortality risk in individuals who smoked and individuals who were physically inactive.

Polyunsaturated fatty acids (PUFA) are essential nutrients with anti-inflammatory and cardioprotective properties. We investigated the association of essential dietary PUFA intake, reflected by plasma fatty acid composition, with inflammation and mortality in dialysis patients. We recruited 222 Swedish dialysis subjects (39% women) with median age of 57 years and average 12 months of dialysis vintage. Plasma phospholipid PUFA were assessed by gas–liquid chromatography. Overall mortality was assessed after 18.4 (10th–90th percentiles: 2.3–60) months of follow-up. Linoleic acid (LA), Mead acid (MA), α-linolenic acid (ALA) and long-chain n-3 PUFA (LC n-3; the sum of eicosapentaenoic, docosapentaenoic and docosahexaenoic acids) represented 19.7, 0.26, 0.26 and 7.64% of all fatty acids in plasma, respectively. This may reflect an adequate n-3 PUFA intake. LA was negatively (β = − 0.21, P = 0.004) but MA positively (β = 0.25, P < 0.001) associated with interleukin (IL)-6 in multivariate analyses. Neither ALA nor LC n-3 were independently associated with IL-6. During follow-up, 61 deaths and 115 kidney transplants occurred. Fully adjusted competing risk models showed that every percent increase in the proportion of plasma LA was associated with 12% reduction in mortality risk before transplantation (hazard ratio 0.88, 95% confidence interval 0.79–0.99). MA was directly associated with mortality. Neither ALA nor LC n-3 predicted outcome. The proportion of plasma phospholipid LA is inversely associated with IL-6 and all-cause mortality in Swedish dialysis patients. We raise the hypothesis that dialysis patients could benefit from increased intake of vegetable oils, the primary source of LA in the Western-type diet.

Replacement of dietary saturated fat with unsaturated fat has been recommended for prevention of cardiovascular disease (CVD) in the general population. Less is known of the health risks in individuals with chronic kidney disease (CKD), of a diet with an unhealthy fat profile, in general characterized by insufficient polyunsaturated fatty acids (PUFA) and excess satu-rated fatty acids (SFA). The dietary intake of PUFA, both the n-3 and n-6 subfamilies, is increasingly gaining attention in CKD, owing to its broad cardioprotective effects. Conversely, dietary SFA may promote CVD in this vulnerable population. This review discusses the potential benefits of dietary fat modification in CKD patients, including plausible effects on renal function, albuminuria, lipoproteins, nutritional status, inflammation, thrombosis and clinical outcomes. Increasing evidence supports the concept that n-3 PUFA might have therapeutic potential in reducing proteinuria in CKD and reducing triglycerides and inflammation in dialysis patients. In addition, emerging evidence suggests that linoleic acid, a major n-6 PUFA derived from vegetable oils, may be beneficial for a number of CVD risk factors. Increased consumption of oily fish as part of plant-based diets with low content of SFA is likely to benefit patients who have CKD, or are at risk of developing CKD. Such recommendations are in line with the concept of a healthy "Mediterranean diet" and are in line with current dietary recommendations for CVD prevention in the community.