Association of Frailty and Malnutrition With Long-term Functional and Mortality Outcomes Among Community-Dwelling Older Adults: Results From the Singapore Longitudinal Aging Study 1

Abstract

Importance: Physical frailty and malnutrition are prevalent among older adults and may be associated with functional and mortality outcomes.

Objective: To assess the health outcomes associated with physical frailty and malnutrition singly and in combination among older adults.

Design, setting, and participants: Population-based cohort study (Singapore Longitudinal Aging Study 1). Included were 2804 community-dwelling adults in Singapore aged 55 years or older at baseline (September 1, 2003, to December 23, 2005), with 2 follow-ups at 2- to 3-year intervals (from March 7, 2005, to September 10, 2007, and from November 13, 2007, to December 12, 2009) and a 12-year mortality follow-up to March 31, 2017. Data analysis was from July 1 to September 28, 2017.

Main outcomes and measures: Baseline physical frailty (Fried criteria) with participants categorized according to the total score as frail (3-5 points), prefrail (1-2 points), or robust (0 point), and nutritional status (Nutrition Screening Initiative DETERMINE Your Nutritional Health Checklist and Mini Nutritional Assessment Short-Form [MNA-SF]). Baseline (prevalent) and follow-up (incident) instrumental/basic activities of daily living (IADL/ADL) disability, poor quality of life (QOL), and mortality were measured. Estimates of association were by odds ratios (ORs) and hazard ratios (HRs) and their 95% CIs.

Results: The participants (mean [SD] age, 66.0 [7.7] years; 1033 [36.8%] male; 2611 [93.1%] Chinese) included 1021 (37.6%) categorized as robust with MNA-SF normal nutrition (R-NN), 330 (12.2%) robust with MNA-SF at risk/malnourished (R-ARM), 734 (27.0%) prefrail/frail with MNA-SF normal nutrition (PFF-NN), and 631 (23.2%) prefrail/frail with MNA-SF at risk/malnourished (PFF-ARM). Among these 2804 participants, 44 had missing frailty status, and 78 had missing MNA-SF nutritional status; therefore, 88 participants in total had missing frailty-nutritional status. In cross-sectional analyses, the prevalence of IADL/ADL disability was lowest among the R-NN group (169 [16.9%]) and increased substantially only among the PFF-ARM group (249 [40.2%]) (OR, 1.88; 95% CI, 1.40-2.53). Poor QOL prevalence was lowest among the R-NN group (142 [14.1%]), and the increase in other frailty and nutritional status groups was highest in the PFF-ARM group (255 [41.3%]) (OR, 2.61; 95% CI, 1.96-3.49). In longitudinal analyses, significant association with only incident poor QOL across frailty and nutritional status groups was highest in the PFF-ARM group (89 [34.8%]) compared with the R-NN group (132 [19.2%]) (OR, 1.70; 95% CI, 1.17-2.48). The mortality rate was lowest in the R-NN group (0.54 per 100 person-years) and highest in the PFF-ARM group (3.04 per 100 person-years) (HR, 1.72; 95% CI, 1.01-2.92). The results based on the Nutrition Screening Initiative measure of nutritional status were similar.

Conclusions and relevance: Reported adverse health outcomes attributed to poor nutrition often appear more likely to be associated with physical frailty. Prefrail/frail older persons with poor nutrition might be targeted for interventions to prevent or delay adverse functional and mortality outcomes.

Figure 1.. Prevalence and Incidence of Adverse Health Outcomes According to Baseline Frailty-Nutritional Status

A, Prevalence of instrumental/basic activities of daily living (IADL/ADL) disability and poor quality of life (QOL) according to baseline frailty and nutritional status (Mini Nutritional Assessment Short-Form [MNA-SF]). B, Prevalence of IADL/ADL disability and poor QOL according to baseline frailty and nutritional status (Nutrition Screening Initiative [NSI]). C, Incidence of IADL/ADL disability and poor QOL according to baseline frailty and nutritional status (MNA-SF). D, Incidence of IADL/ADL disability and poor QOL according to baseline frailty and nutritional status (NSI).

Figure 2.. Kaplan-Meier Survival Curves of Older Adults in the Singapore Longitudinal Aging Study 1 Cohort

Kaplan-Meier survival curves were plotted to compare the survival rates up until March 31, 2017, according to baseline frailty and nutritional status. A, Kaplan-Meier survival curve according to baseline frailty and nutritional status (MNA-SF, n = 2500; P < .001). B, Kaplan-Meier survival curve according to baseline frailty and nutritional status (NSI, n = 2533; P < .001).