Daily Heart Rate in Relation to Cardiorespiratory Fitness and Metabolic Syndrome in HIV+ Hispanic Adults

Abstract

Daily heart rate (HR) is usually higher among HIV+ compared with HIV- adults, a possible aspect of chronotropic incompetence (CI) in this population. Low cardiorespiratory fitness (CRF) and metabolic syndrome (MetSyn) are prevalent among HIV+ adults, possibly influencing CI. However, information regarding 24-hr HR as an index of CI, and its association with CRF and MetSyn in this population is nonexistent. PURPOSE: To describe the association between CRF, MetSyn, and daily HR in a group of HIV+ and HIV- Hispanic adults in Puerto Rico. METHODS: Eighty-Nine adults (59-HIV+ and 30 HIV-) completed measurements of CRF (VO2 peak), 24-hr blood pressure and HR, and metabolic syndrome (fasting glucose and lipid profile, resting BP, waist circumference). T-tests were used to detect differences between groups, and correlation analyses to evaluate associations between variables. RESULTS: The proportion of low CRF based on age and sex, and MetSyn was not different between HIV+ and HIV-participants (56 vs. 40%; and 53 vs. 37%; P=0.2, respectively). However, 24-hr HR, daytime HR, and night-time HR were all significantly higher in HIV+ compared with HIV- participants (78.3±9.4 vs. 67.4±8.4, 81.9±9.9 vs. 69.7±8.6, 70.7±9.4 vs. 62.7±9.0 bpm, respectively, P<0.05 for all). VO2 peak was inversely correlated with 24-hr HR, daytime HR, and night-time HR in both groups (ρ= -0.40, -0.36, -0.49, P<0.05 for all). Considering CRF classification in each group, all HR measures were significantly lower among those with high CRF vs. low CRF regardless of HIV status (HIV+: 24-hr HR by CRF: low= 81.1±8.2 vs. high= 74.8±9.7 bpm, P=0.009; daytime HR: low=85.0±8.7 vs. high=78.0±10.2 bpm, P=0.006; night-time HR: low=72.8±8.7 vs. high=68.0±9.8 bpm, P=0.02) (HIV-: 24-hr HR by CRF: low= 72.1±4.4 vs. high= 64.2±9. bpm, P=0.009; daytime HR: low=74.1±4.9 vs. high=66.8±9.4 bpm, P=0.02; night-time HR: low=67.8±6.1 vs. high=59.2±9.1 bpm, P=0.008). No HR differences were observed by MetSyn in the HIV+ group, but HR measures in the HIV- group were lower in those without MetSyn. CONCLUSION: These results suggest that CRF but not MetSyn, influence daily HR in HIV+ participants, with potential impact on CI correction. Intervention studies must be conducted to confirm these results. Supported by: NIH/CTSA KL2-RR024151, NIH/NIMHHD 8U54MD 007587-03.