Validity and reproducibility of a short food frequency questionnaire among patients with chronic kidney disease

Abstract

BackgroundA balanced diet is essential to slowing the progression of chronic kidney disease (CKD) and managing the symptoms. Currently, no tool is available to easily and quickly assess energy and macronutrient intake in patients with non end-stage CKD.We aimed to develop and evaluate the validity and reproducibility of a new short 49-item food frequency questionnaire (SFFQ) adapted to patients with CKD.MethodsThe CKD-REIN study is a prospective cohort that enrolled 3033 patients with moderate or advanced CKD from a national sample of nephrology clinics. A sub-sample of 201 patients completed the SFFQ twice, at a one-year interval and were included in the reproducibility study. During this interval, 127 patients also completed six 24-h recalls and were included in the validity study. Main nutrient and dietary intakes were computed. Validity was evaluated by calculating crude, energy-adjusted and de-attenuated correlation coefficients (CC) between FFQ and the mean of the 24-h recall results. Bland-Altman plots were performed and cross-classification into quintiles of consumption of each nutrient and food group was computed. Reproducibility between the two SFFQs was evaluated by intraclass CC (ICC).ResultsRegarding validity, CC ranged from 0.05 to 0.79 (unadjusted CC, median: 0.40) and 0.10 to 0.59 (de-attenuated CC, median: 0.35) for food group and nutrient intakes, respectively. Five of the most important nutrients of interest in CKD, i.e. protein, calcium, phosphorus, potassium, and sodium had de-attenuated CC of 0.46, 0.43, 0.39, 0.32, and 0.12, respectively. The median of classification into the same or adjacent quintiles was 68% and 65% for food and nutrient intakes, respectively, and ranged from 63% to 69% for the five nutrients mentioned before. Bland-Altman plots showed good agreement across the range of intakes. ICC ranged from 0.18 to 0.66 (median: 0.46).ConclusionsThe CKD-REIN SFFQ showed acceptable validity and reproducibility in a sample of patients with CKD, notably for CKD nutrients of importance. It can now be used in large-scale epidemiological studies to easily assess the relations between diet and CKD outcomes as well as in clinical routine. It may also serve as a basis for the development of FFQs in international CKD cohort networks.Electronic supplementary materialThe online version of this article (10.1186/s12882-017-0695-2) contains supplementary material, which is available to authorized users.

Relative Validity and Reproducibility of a New 44-Item Diet and Food Frequency Questionnaire Among Adults: Online Assessment (Preprint)

“…As previously described (8), a consortium of 6 cohort studies (E3N(9), E4N(10), CKD-REIN(11), iShare (12), Elfe (13) and Psy-COH) was set up to create a unique Short Food Frequency Questionnaire (SFFQ) that could quickly assess the habitual diet in several populations: adults, the elderly, adolescents, students, patients with mental disorders, and patients with chronic kidney disease.…”

“…In a pilot study, a paper version of the consortium SFFQ has already been validated in a sample of patients with chronic kidney disease (CKD) (8) and showed acceptable validity and reproducibility in this specific population, notably for CKD nutrients of importance. The aim of the present study was to study the reproducibility of the online version of the newly developed SFFQ (SFFeQ), and evaluate its validity against 24-hour recalls in a sample of French adults.…”

Potential applications of a new short food frequency questionnaire for CKD patients

“…In BMC Nephrology , Affret et al report on their study of the reproducibility of a newly developed short 49-item food frequency questionnaire (SFFQ) adapted to patients with CKD [ 4 ]. They evaluated the feasibility and validity of the SFFQ in the CKD-REIN (CKD-Renal Epidemiology and Information Network) which is a prospective cohort of adults with moderate or advanced CKD (stages 3 to 4) drawn from a nationally representative sample of nephrology facilities in France [ 5 ].…”

“…Elucidating these patterns could advance our understanding of potential nutritional intervention targets in CKD. For example, in the report by Affret et al, a total of 37.8% and 39.3% of participants in the validity and reproducibility studies, respectively, had diabetes [biopsy-proven causes of kidney disease in the study were not noted] [ 4 ]. Their hemoglobin A1C values were controlled, at 6.3% in both groups.…”

“…sodium < 1500 mg/day) used to define a heart healthy diet not being comparably relevant for kidney disease risk [ 10 ]. Notably, Affret et al found significant differences between sodium intakes as estimated by 24-h recalls (5058.4 mg/day) as compared to the second SFFQ (2319.3 mg/day) [ 4 ]. The relative contribution of sodium intake as compared to other health behaviors among persons with CKD, would be an interesting investigation, for which a SFFQ might be applied.…”