Nutritional status, knowledge, attitude and practices of patients receiving maintenance hemodialysis in Bloemfontein, South Africa
Background: Internationally, the nutritional management of patients on maintenance hemodialysis (MHD) poses a challenge. This is the first Sub-Saharan study to focus on knowledge, attitudes and practices (KAP) regarding the renal diet required for patients on MHD. Methods: A descriptive, cross sectional study was performed during 2017 on 75 participants receiving MHD in Bloemfontein, a mid-sized city in central South Africa. Questionnaires were administered during structured interviews, and anthropometry, pre-dialysis biochemistry and information from the patient files were documented. Results: The participants were mostly men (70.7); median age, 50.5 years; median education level, Grade 12. The etiology of renal failure included hypertension (37.3 %), diabetes mellitus (DM) (6.7 %), or both (10.7 %). Home-languages were mostly Sesotho (46.7 %) and Afrikaans (4 %), and second languages, English (61.4 %) and Sesotho (18.7 %). Most (64 %) lived in overcrowded conditions, 38.7 % received a social grant, and only 24 % were employed full-time. Furthermore, 41.7 % had an income <R1 500 per month (pm); the median percentage of income available for food per person (pp) pm, was 27.3 % (the suggested in 2017 was 40 %), and 78.9 % were spending <40 % of income pp/pm on food. Median body mass index (BMI) was 26.4 kg/m2, with 23 % overweight (<25.0 - <30.0 kg/m2), 33.8 % obese (>30 kg/m2) and only 5.3 % underweight (<18.5 - >17.0 kg/m2). Most (66.2 %) had a weight-to-height-ratio (WHtR) >0.5, indicating increased risk for metabolic comorbidities. Body fat (BF) percentages were above normal (>85th percentile) for 25.4 %. Yet, 56 % had arm muscle areas (AMA) < 15th percentile and 29.3 % had body fat (BF) percentages <5th percentile. In fact, of those with AMA <15th percentile, 31 % (n= 13) had BMI >25 kg/m2 (indicating overweight), and 57 % (n= 24) had a normal BMI (>18.5 kg/m2 to < 24.9 kg/m2). Without C-reactive protein (CRP) testing, the low serum albumin levels (<35 g/L) in 49.3 % of participants, as well as hypocholesterolemia (53.3 %, n= 8 out of 15) and low white blood cell counts (WBC) (26.4 %, n= 14), cannot be ascribed to malnutrition with certainty. Yet, pre-dialysis low serum urea levels (<21 mmol/L) in 52.5 % (n= 32) in the presence of low protein intakes (particularly low high biological value (HBV) protein), could point to malnutrition. Overall, 28 % (n= 21) had low hemoglobin levels (<10 g/dL) and 18.9 % (n= 14), had low TSAT values (<20 %), possibly indicating iron shortage. Serum phosphate (PO4) levels were >1.8 mmol/L for 25.3 %, and above 1.42 mmol/L for 49.3 %. Compared to NKF-K/DOQI guidelines, 44.6 % of participants had energy intakes <30 kcal/kg (dry weight/adjusted edema-free body weight [aBWef]), whilst 46 % consumed >35 kcal/kg. Similarly, 48.6 % had total protein (TP) intakes <1.2 g/kg (dry weight/aBWef), and 43.2 % consumed >1.3 g/kg. Overall, 40 % had consumed inadequate amounts of HBV protein (<50% of TP). Those participants with inadequate HBV protein intake (<50 % of TP) had statistically significantly lower pp income than those with above adequate intakes of HBV protein (>75 % of TP) (95 % CI [R4 416.70 ; R19 000.00]), and spent statistically significantly less pp on food (95 % CI [R216.70 ; R1 309.50]). Overall, 49.4 % had poor combined knowledge (<50 %) of restricted foods, mineral content of food, and phosphate binder medication. Participants with tertiary education (28 %) had statistically significantly better knowledge than those with only primary school education (6.7 %) (95 % CI [3.9 % ; 73.5 %]), and to those who had only partially completed secondary school (17.3 %) (95 % CI [6.3 % ; 64.0 %]). Only, 21 % had received written and 30.7 % verbal, nutrition education (NE) in their home language. Overall, 24 % had not received NE in their home and/or second language. Having received NE in a home language and/or second language was associated with statistically significantly higher overall knowledge scores (95 % CI [3.7 % ; 49.5 %]. In addition, participants with lower phosphate intakes (<10 mg PO4/g protein) (23 %), scored statistically significantly better on knowledge regarding phosphate binders, than those (60.8 %) with a higher phosphate intake (>12 mg PO4/g protein) (95 % CI [2.9 % ; 52.5 %]). Most (60 %) felt negative about the renal diet, and (61.4 %) reported poor adherence practices. Most (77.3 %) reported ≤1 consultation with a dietitian per MHD year (NKF-K/DOQI recommendation: >3). Conclusion: This sub-Saharan population on MHD presented with substantial overweight and obesity, indicating high risk for cardiovascular complications; yet, excessive body fat levels, masked muscle wasting. Protein intake, particularly, HBV protein intake were below recommendations, and significantly associated with lower income levels. Most participants showed inadequate knowledge (significantly associated with education level and receiving NE in a first or second language), negative attitudes, and poor compliance practices regarding the renal diet and dietitians were inadequately involved in the treatment of these patients.