A proinflammatory diet may increase the risk for new-onset end-stage kidney disease (ESKD) in postmenopausal women initially free from chronic kidney disease (CKD), according to investigators of a new study presented at the American Society of Nephrology’s Kidney Week 2021.
Among 15,722 participants in the 1993-1998 Women’s Health Initiative (WHI) study, ESKD developed in 515 women over a mean follow-up period of 11.5 years. At baseline, kidney function was normal: Mean serum creatinine was 0.74 mg/dL and mean estimated glomerular filtration rate (eGFR) was 89 mL/min/1.73 m2. Hypertension affected 40%, and diabetes 9%.
Based on food frequency questionnaire responses, the investigators scored the inflammatory potential of each woman’s diet using the dietary inflammatory index (DII). The index evaluates the effects of 45 food parameters on 6 markers of inflammation (hs-CRP, tumor necrosis factor alpha, and interleukins 1β, 4, 6, and 10). The DII also rewards consumption of bioactive component such as herbs, spices (eg, ginger, turmeric), and flavonoids. Quartile 4 reflected a diet with the highest inflammatory potential, such as excess saturated fats from meat and very few fruits and vegetables. Quartile 1 had the lowest inflammatory potential.
Women with dietary scores in quartile 4 vs quartile 1 had a significant 20% increased risk for ESKD, even after adjusting for age, ethnicity, hypertension, diabetes, cardiovascular disease, body mass index, education, medications, and region, Tanya Johns, MD, MHS, of Albert Einstein College of Medicine in the Bronx, New York, reported for her team. Compared with White women, Black and Hispanic women were 30% and 19% more likely to consume foods with scores in quartile 4. Women who did not complete high school or had an annual family income less than $10,000 also were more likely to have a diet in quartile 4.
In an interview with Renal & Urology News, Dr Johns noted that food insecurity and neighborhood factors, such as more fast-foods chains and fewer grocery stores, can limit access to healthier foods. Food traditions, social circles, and social setting also influence eating habits.
Women with the most pro-inflammatory dietary patterns were more likely to have a history of hypertension and a higher body mass index. They were also more likely to be smokers.
“Inflammation may be another pathway whereby certain dietary patterns influence CKD progression and may be a potentially modifiable risk factor or target for intervention,” Dr Johns said. “If our findings are replicated in dietary trials, eating a healthier, less inflammatory diet may delay progression of kidney disease.”
An anti-inflammatory dietary pattern is rich in whole grains, n-3 long chain polyunsaturated fatty acids, fish, fruits, vegetables, and certain bioactive components. The DASH diet or a Mediterranean diet are 2 well-known examples.
Johns TS, Mossavar-Rahmani Y, Hebert JR, Franceschini N, Melamed ML. Dietary inflammatory potential and the risk of incident ESKD in the Women’s Health Initiative. Presented at: Kidney Week 2021; November 2-7, 2021. Presentation: PO2242.