This longitudinal study examines changes to speech production and speech breathing in older adults with Parkinson's disease (PD) and older adults without PD. Eight participants with PD and eight age- and sex-matched older adults participated in two data collection sessions, separated by 3.7 years on average. Speech severity and speech rate increased for people with PD. Vital capacity decreased for both groups. Older adult control participants displayed significant increases in lung volume initiation and excursion and percent vital capacity expended per syllable. These changes allow older adults to utilize higher recoil pressures to generate subglottal pressure for speech production, potentially reducing work of breathing. Participants with PD displayed significant decreases in lung volume initiation and termination. Thus, unlike older adults, people with PD exert more expiratory muscle pressure during speech production, leading to increased effort. Speech-language pathologists need to consider direct treatment of respiratory patterns for speech to reduce effort and fatigue.