Undernutrition drives up hospitalizations for older Singaporeans

New research points to undernutrition as a key factor contributing to increases in emergency department (ED) visits and inpatient admissions among older adults in Singapore.

In a cohort of 1,703 community-dwelling adults enrolled in the Population Health Index (PHI) study, undernourished individuals had an average of 0.35 more ED visits and 0.42 more inpatient admissions compared with their well-nourished peers. The corresponding incidence rate ratios (IRRs) were 1.41 (95 percent confidence interval [CI], 1.09–1.84) for ED visits (p=0.010) and 1.52 (95 percent CI, 1.11–2.10) for inpatient admissions (p=0.011).  [Nutrients 202;17:1781]

Notably, the association between nutritional status and healthcare utilization varied significantly by age, according to the investigators.

Among older adults, undernutrition was linked to a substantially higher number of ED visits (average marginal effect, 0.49; p=0.001) and inpatient admissions (average marginal effect, 0.47; p=0.008) but significantly fewer visits to primary care (IRR, 0.72, 95 percent CI, 0.52–0.99; p=0.042) and specialist outpatient clinics (IRR, 0.57, 95 percent CI, 0.40–0.80; p=0.001).

On the other hand, among younger adults, undernutrition had no notable effect on ED visits and inpatient admissions (p>0.05 for both) but was associated with significantly more specialist outpatient clinic visits (average marginal effect, 0.46; p=0.005).

No significant differences were observed for primary care visits or day surgery procedures.

Undernutrition prevalence

In this study, nutritional status was assessed using the 18-item full Mini Nutritional Assessment, with undernutrition defined as a total nutritional score of below 24 out of 30 points. A total of 165 participants (9.7 percent) were classified as undernourished, with a significantly greater prevalence among older than younger adults (15.0 percent vs 6.7 percent; p<0.001).

Compared with well-nourished participants, those who were undernourished were more likely to have a higher age (mean age, 59.1 vs 51.8 years; p<0.001), be female (64.9 percent vs 52.9 percent; p=0.003), have lower educational attainment (no formal education: 35.2 percent vs 12.6 percent; p<0.001), be unemployed (67.3 percent vs 33.9 percent; p<0.001), have multimorbidity (61.8 percent vs 34.7 percent; p<0.001), and have inadequate financial resources (30.3 percent vs 13.2 percent; p<0.001).

Factors strongly associated with undernutrition included female sex (odds ratio [OR], 2.20, 95 percent CI, 1.40–3.44), being unemployed/retired/inactive (OR, 2.91, 95 percent CI, 1.94–4.38), financial inadequacy (OR, 1.94, 95 percent CI, 1.28–2.95), and current smoking (OR, 2.70, 95 percent CI, 1.56–4.67).

“To the best of our knowledge, this is the first study investigating the dynamic association between undernutrition and healthcare utilization across different care settings among community-dwelling adults in Singapore,” the investigators said.

They noted that the patterns of healthcare utilization observed in the local cohort align with global evidence and may reflect delayed care-seeking among undernourished individuals.

“Undernourished older adults living in the community face systemic barriers to accessing primary and specialist care due to multiple reasons (eg, mobility limitations, under-recognition of undernutrition symptoms, or transport challenges), leading to delayed care-seeking until acute crises necessitate emergency care or hospitalisations,” the investigators explained.

“Notably, the observed reduction in primary and specialist outpatient clinic visits among older undernourished adults contrasted with the increased specialist outpatient clinic utilization among younger undernourished adults. This paradox [indicates that] younger adults might proactively seek specialist care for early symptoms, while older adults delay care until conditions escalate,” they added.

Public health implications

Considering the study’s implications for public health in Singapore, the investigators proposed recommendations for public health initiatives.

First is the integration of routine nutritional screening into primary care and community settings, particularly for high-risk subgroups such as women, individuals without formal education, those who are unemployed, retired, or economically inactive, current smokers, and individuals with multiple chronic conditions.

“Early identification of undernutrition in these vulnerable populations may enable timely intervention and reduce downstream burden on healthcare services,” the investigators said.

Another is the implementation of tailored intervention strategies to address specific access barriers.

“For instance, older adults facing mobility limitations or transportation challenges could benefit from mobile health clinics or home-based nutritional services that deliver personalised support while improving reach and adherence. Financially vulnerable individuals who struggle to access healthy food due to limited income or social support could benefit from targeted food assistance and community nutrition programmes, such as Share-A-Pot, which offer both nutritional and social support,” they continued.

The investigators emphasized that their recommendations align well with Singapore’s population health management strategy, which focuses on preventive care and integrated chronic disease management within the community. “By embedding nutritional care as a foundational component of these efforts, public health systems can better address the modifiable risk of undernutrition and reduce avoidable hospital admissions.”