Abstract Body (Do not enter title and authors here): Introduction: Natriuretic peptides (NPs) are hormones produced by the heart in response to cardiac wall stress, stimulating natriuresis and vasodilation. NP levels vary by age, sex, and ethnicity, and their deficiency has been associated with adverse metabolic health among Caucasian and Black adults. South Asians have distinct cardio-metabolic profiles; however, the reference range of NPs and NP deficiency among older South Asian adults is not established.
Method: Participants of the Longitudinal Aging Study in India who were part of the ancillary study on diagnostic assessment of dementia (LASI-DAD) and were free of CVD and CKD at baseline were included. NT-ProBNP was measured using a one-step immunoassay sandwich method (mini VIDAS platform, bioMèrieux, France). Median NT-ProBNP levels were compared across different age, sex, and BMI groups. Generalized Additive Models accounting was used to fit the quantiles of NT-proBNP according to age among males and females separately. The association of NP deficiency (<2.5th percentile for age and sex) with different cardiometabolic traits was assessed using linear models adjusted for age, sex, and BMI.
Result: The study included 2,450 South Asian participants (45.4% male, age 67 y [IQR 63-72]). NT-ProBNP levels increased linearly across increasing age groups, with females (vs. males) having modestly higher NT-proBNP levels in the age groups of 60 – 69 y (119 vs 95 pg/mL)and 70 – 79 y (164 vs 151.5 pg/mL). NT-ProBNP levels decreased linearly across BMI categories among females (Figure). In contrast, among males, the NT-ProBNP levels had a U-shaped distribution across BMI categories, with the lowest level noted in overweight males (Figure). In adjusted analysis accounting for age, sex, and BMI, NP-deficiency was associated with hypertriglyceridemia (OR[95%CI]:1.78[ 1.18, 2.68]) and hyperlipidemia (OR[95%CI]: 2.01[1.22, 3.31]) but not hypertension (OR[95%CI]:0.73[ 0.50, 1.06])
Conclusion: This study establishes the normative values of NT-proBNP across different age and sex groups for South Asian older adults. NP deficiency was associated with hyperlipidemia and hypertriglyceridemia and may contribute to adverse cardiometabolic health in South Asians.