Association between mid-upper arm circumference and weight for height with long-term survival in South Kivu, eastern Democratic Republic of Congo: Lwiro cohort

INTRODUCTION: Little information is available on the relationship between mid-upper arm circumference (MUAC) and weight-for-height Z-score (WHZ) with long-term survival. This study explores the association between MUAC and WHZ of former children hospitalized for severe acute malnutrition (SAM) with their long-term survival after nutritional rehabilitation. METHODS: This was a cohort of adults followed in childhood for SAM between 1988 and 2007 at the Lwiro Pediatric Hospital (HPL) and traced 11 to 30 years after their nutritional rehabilitation in South Kivu, DRC. Childhood data included anthropometry, clinical characteristics, and nutritional edema. Anthropometric indicators (WHZ, MUAC, HAZ, and WAZ) were classified according to WHO thresholds. The dependent variable was long-term survival. Associations between admission WHZ, MUAC, and survival were assessed using Cox regression, with indicators analyzed separately and in combination. Reference groups were defined based on WHO thresholds (MUAC ≥ 125 mm, WHZ ≥ -2, and, for combined analyses, absence of both WHZ < -3 and MUAC < 115 mm). RESULTS: We sampled 670 participants, 461 of whom were traced to adulthood, of whom 12.2% had died. The median age of living participants was 26 years, with a mean age at admission of 32 months during childhood. Among them, 71.1% had nutritional edema, 88.5% had stunting, 14.5% had WHZ < -3, and 22.3% had MUAC < 115 mm. Children with MUAC < 115 mm or WHZ < -3 had a higher, although non-significant, risk of long-term death compared to those without SAM as defined by these criteria. In univariate analyses, children with edema, including those with concurrent anthropometric deficits, showed an increased but non-significant risk of mortality. After adjustment for multiple factors, only WHZ < -3, when analyzed independently, was significantly associated with long-term mortality [adjusted HR (95% CI) = 2.7 (1.1-6.8), p = 0.03]. CONCLUSION: WHZ < -3 was associated with increased long-term mortality. These findings highlight the need to strengthen post-discharge follow-up and long-term care strategies to improve survival in this high-risk group.