(601) Blood-based clinical biomarkers of nutrition and inflammation and preterm birth (PTB) risk

The prognostic nutritional index (PNI) and hemoglobin-albumin-lymphocyte-platelet (HALP) indices are novel, peripheral blood measures of overall nutritional status and inflammation. The PNI and HALP are independent prognostic factors for cancer, overall survival, and other outcomes. Limited studies have evaluated PNI and/or HALP in the prediction of inflammatory-mediated obstetric outcomes such as preterm birth (PTB).


Study Design:

Retrospective, observational cohort of patients with singleton gestations and a BMP or CMP and CBC w/diff drawn < 20 wks’ as part of clinical care at a Univ. Hospital, 2014-2021. Serum albumin (alb), absolute peripheral lymphocyte (L), hemoglobin (hgb), and platelet (P) counts were used to calculate the PNI [(alb * 10) + (L * 0.005)] and HALP [hgb * alb * (L/P)]. The primary outcome was PTB < 37 wks, regardless of indication. PNI and HALP were evaluated continuously and then dichotomized using quartiles; those with values in Q1 (lowest, indicating the worst nutritional & inflammation status) were compared to those with higher values (Q2, Q3, Q4). Data were analyzed by chi-square and t-test. Regression models estimated the relationship between PTB and PNI and HALP; all initial models controlled for pregest. DM, chronic HTN, and history of PTB.


Results:

784 patients met inclusion criteria; 125 (16%) delivered preterm < 37 weeks. Cohort characteristics are shown in Table 1. Low-PNI was < 36.0 (mean 33.3) vs. higher-PNI (range 36.0-51.1, mean 41.0); low-HALP was < 0.28 (mean 0.20) vs. higher-HALP (range 0.28-5.26, mean 0.79). PNI values (mean 38.4 vs. 39.2, p=0.109) and HALP values (median 0.35 vs. 0.39, p=0.076) were similar among those with PTB and term birth, respectively. In regression models, neither low-PNI (aOR 0.98, 95% CI 0.58-1.66) nor low-HALP (aOR 1.29, 95% CI 0.77-2.14) were associated with PTB.


Conclusion:

Peripheral blood inflammatory indices can be calculated from readily available clinic labs; in this cohort, neither the PNI nor HALP were associated with PTB when evaluated early in pregnancy.