Mitochondrial DNA variants and pulmonary function in older persons

Abstract Background We provide the first examination of mitochondrial DNA (mtDNA) variants and pulmonary function in older persons. Methods Cross-sectional associations between mtDNA variants and pulmonary function were evaluated as a combined p -values meta-analysis, using data from two independent cohorts of older persons. The latter included white and black participants, aged ≥70 years, from the Lifestyle Interventions and Independence for Elders study (LIFE) ( N  = 1247) and the Health, Aging and Body Composition study (Health ABC) ( N  = 731), respectively. Pulmonary function included the forced expiratory volume in one-second as a Z -score (FEV1z) and the maximal inspiratory pressure (MIP) in cm of water. Results In black participants, significant associations were found between mtDNA variants and MIP: m.7146A > G, COI ( p  = 3E-5); m.7389 T > C, COI ( p  = 2E-4); m.15301G > A, CYB ( p  = 9E-5); m.16265A > G, HV1 (p = 9E-5); meta-analytical p -values p  = 0.004), complex V ( p  = 0.0007), and hypervariable ( p  = 0.003) regions. The individual and aggregate variant results were significant after adjustment for multiple comparisons. Otherwise, no significant associations were detected for MIP in whites or for FEV1z in whites or blacks. Conclusions We have shown that mtDNA variants of African origin are cross-sectionally associated with MIP, a measure of respiratory muscle strength. Thus, our results establish the rationale for longitudinal studies to evaluate whether mtDNA variants of African origin identify those at risk of subsequently developing a respiratory muscle impairment (lower MIP values).