Pulmonary and physical function limitations in aging men with and without HIV from the Multicenter AIDS Cohort Study (MACS)

Purpose: We examined the associations between pulmonary impairments and physical function and whether age, HIV serostatus, or smoking modified these relationships. Methods: Using Multicenter AIDS Cohort Study data, we examined associations between pulmonary function (diffusing capacity for carbon monoxide [DL_CO], one-second forced expiratory volume [FEV₁]) and subsequent physical outcomes (gait speed, grip strength, frailty [non-frail, pre-frail, frail]) using mixed models. Results: Of 1,048 men, 55% were living with HIV, median age was 57(IQR=48,64) and median cumulative pack-years was 1.2(IQR = 0,18.1); 33% and 13% had impaired DL_CO and FEV₁(<80% predicted), respectively. Participants with impaired DL_CO had 3.5 kg (95%CI: -4.6, -2.4) weaker grip strength, 0.04 m/sec (95%CI: -0.06, -0.02) slower gait speed and 4.44-fold (95%CI: 1.81, 10.93) greater odds of frailty compared to participants with normal DL_CO. Participants with impaired FEV₁ had 3.1 kg (95%CI: -4.8, -1.4) weaker grip strength, similar gait speed (-0.001 m/sec [95%CI: -0.04, 0.03]) and 5.72-fold (95%CI: 1.90, 17.19) greater odds of frailty compared to participants with normal FEV₁. Age, but not smoking or HIV, significantly modified the DL_CO effect on gait speed and grip strength. Conclusions: Pulmonary impairment and decreased physical function were associated. Preserving pulmonary function may help preserve physical function in aging men with and without HIV.