Background: Poor appetite could be indicative of protein energy wasting (PEW) and experts recommend assessing appetite in dialysis patients. Our study aims to determine the relationship between PEW and appetite in haemodialysis (HD) patients.
Methods: HD patients (n=205) self-rated their appetite on a scale of 1 to 5 as very good (1), good (2), fair (3), poor (4) or very poor (5). Nutritional markers were compared against appetite ratings. Using logistic regression analysis associations between dichotomized appetite with PEW diagnosis were determined as per the International Society of Renal Nutrition and Metabolism (ISRNM) criteria and alternate objective measures. Data was adjusted for socioeconomic and demographic characteristics.
Results: Poorer appetite ratings were significantly associated with lower income (P = 0.021), lower measurements (P < 0.05) for mid-arm muscle circumference, mid-arm muscle area and lean tissue mass (LTM), serum urea (P = 0.007) and creatinine (P = 0.005). The highest hsCRP (P = 0.016) levels occurred in patients reporting the poorest appetite. Serum albumin did not differ significantly across appetite ratings. Poor oral intake represented by underreporting (EI/BMR < 1.2) was evident for all appetite ratings. PEW was prevalent irrespective of appetite ratings (very good: 17.6 %, good: 40.2 %, fair: 42.3 % and poor: 83.3 %). After dichotomizing appetite ratings into normal and diminished categories, there was a marginal positive association between diminished appetite and overall PEW diagnosis (OR adj: 1.71; 95 % CI: 0.94-3.10, P = 0.079). Amongst individual ISRNM criteria, only BMI < 23 kg/m2 was positively associated with diminished appetite (OR adj: 2.17; 95 % CI: 1.18-3.99). However, patients reporting diminished appetite were more likely to have lower LTM (OR adj: 2.86; 95 % CI: 1.31-6.24) and fat mass (OR adj: 1.91; 95 % CI: 1.03-3.53), lower levels of serum urea (OR adj: 2.74; 95 % CI: 1.49-5.06) and creatinine (OR adj: 1.99; 95 % CI: 1.01-3.92), higher Dialysis Malnutrition Score (OR adj: 2.75; 95 % CI: 1.50-5.03), Malnutrition Inflammation Score (OR adj: 2.15; 95 % CI: 1.17-3.94), and poorer physical (OR adj: 3.49; 95 % CI: 1.89-6.47) and mental (OR adj: 5.75; 95 % CI: 3.02-10.95) scores.
Conclusions: A graded but non-significant increase in the proportion of PEW patients occurred as appetite became poorer. However, after dichotomization, a positive but marginally significant association was observed between diminished appetite and PEW diagnosis.