INTRODUCTION: Outpatient appointment nonattendance (NA) represents a public health problem, increasing the risk of unfavorable health-related outcomes. Although NA is significant among older adults, little is known regarding its correlates. This study aimed to identify the correlates (including several domains from the geriatric assessment) of single and repeated NA episodes in a geriatric medicine outpatient clinic, in general and in the context of specific comorbidities. METHODS: This is a cross-sectional study including data from 3,034 older adults aged ≥60 years with ≥1 scheduled appointments between January 1, 2016, and December 31, 2016. Appointment characteristics as well as sociodemographic, geographical, and environmental information were obtained. Univariate and multivariate multinomial regression analyses were carried out. RESULTS: The mean age was 81.8 years (SD 7.19). Over a third (37.4%) of participants missed one scheduled appointment, and 14.4% missed ≥2. Participants with a history of stroke (OR 1.336, p = 0.041) and those with a greater number of scheduled appointments during the study time frame (OR 1.182, p < 0.001) were more likely to miss one appointment, while those with Parkinson's disease (OR 0.346, p < 0.001), other pulmonary diseases (OR 0.686, p = 0.008), and better functioning for activities of daily living (ADL) (OR 0.883, p < 0.001) were less likely to do so. High socioeconomic level (OR 2.235, p < 0.001), not having a partner (OR 1.410, p = 0.006), a history of fractures (OR 1.492, p = 0.031), and a greater number of scheduled appointments (OR 1.668, p < 0.001) increased the risk of repeated NA, while osteoarthritis (OR 0.599, p = 0.001) and hypertension (OR 0.680, p = 0.002) decreased it. In specific comorbidity populations (hypertension, type 2 diabetes mellitus, and cancer), better ADL functioning protected from a single NA, while better mobility functioning protected from repeated NA in older patients with hypertension and cancer. DISCUSSION/CONCLUSION: Identifying geriatric factors linked to an increased probability of NA may allow one to anticipate its likelihood and lead to the design and implementation of preventive strategies and to an optimization of the use of available health resources. The impact of these factors on adherence to clinical visits requires further investigation.