OSAS.MAP10 and all-cause mortality risk in hypertensive patients: a retrospective cohort analysis of NHANES.

Abstract

Background and research question: Hypertension and obstructive sleep apnoea (OSA) commonly coexist in older adults. OSAS.MAP10 is a symptom-based screening score estimating OSA risk, not a polysomnographic severity measure. We examined its association with all-cause mortality, and explored nonlinear patterns among hypertensive adults.

Methods: We analysed 6930 hypertensive adults from NHANES 2005-2008 and 2015-2018. The primary outcome was all-cause mortality; cardiovascular and cancer mortality were secondary outcomes. We used survey-weighted Cox models and restricted cubic splines adjusting for age, sex, race and ethnicity, BMI, education, family poverty income ratio, smoking status, diabetes, baseline cardiovascular disease, current antihypertensive medication use, and survey period. In adults aged ≥60 years, the age-stratified model without continuous age was primary, and additional continuous-age adjustment was evaluated as a sensitivity analysis.

Results: Among 6930 hypertensive adults, 1199 deaths occurred. In the complete-case analysis of participants aged ≥60 years (n = 3982; 1006 deaths), the OSAS.MAP10-mortality association was nonlinear (P for nonlinearity <0.001). In the age-stratified model without continuous age, each 1-point increase at or above 6.19 was associated with higher mortality (HR 1.21; 95% CI 1.02-1.44; p = 0.029). After age additional adjustment , the association was attenuated (HR 0.96; 95% CI 0.83-1.12; p = 0.643). Cardiovascular mortality showed no significant nonlinearity.

Conclusions: Higher OSAS.MAP10 scores showed a nonlinear association with all-cause mortality among hypertensive adults aged ≥60 years. The increase above approximately 6.2 was observed only without continuous age adjustment and was attenuated thereafter. This inflection point is hypothesis-generating and requires validation in an independent cohort.