2.3. Geriatric nutritional risk index

The GNRI was calculated using the following formula: GNRI = (1.489 × serum albumin [g/L]) + (41.7 × weight [kg]/ideal body weight [kg]). Ideal body weight was determined as 22 × the square of height, as previously described (20, 24, 26). The variables used in this formula were assessed during the baseline visit to KoGES. Previously, GNRI values were divided into three categories: < 82, < 92, 92–98, and > 98 for major, moderate, low and no “nutrition-related risk,” respectively (21), and into two categories: GNRI <98 and GNRI >98, indicating malnutrition and adequate nutrition, respectively (20). Because the number of participants categorized as 92 < GNRI ≤98, and GNRI <92 was small (less than 5% of total participants) in this study, the presence of malnutrition risk based on GNRI was categorized into two levels: GNRI ≤98; and GNRI >98. Recent studies have shown that the GNRI is applicable to participants regardless of their body fluid status or disease type. Hence, this study did not limit the study participants owing to the presence of disease status.