Journal of Disease and Global Health

Nigeria is undergoing a rapid demographic transition, with a growing proportion of its population entering old age. Despite this trend, the mental health needs of older adults remain significantly under-addressed. Among the most pressing challenges are loneliness, social isolation, and depression—interrelated but distinct psychosocial conditions that contribute profoundly to morbidity, diminished quality of life, and premature mortality in later life. Loneliness refers to the subjective perception of inadequate social relationships, while social isolation is defined by a lack of actual social contact; both are potent risk factors for late-life depression, which is often underdiagnosed and untreated in Nigeria. This review synthesizes current evidence on the prevalence, determinants, and consequences of these conditions among older Nigerians. Key risk factors include the erosion of extended family networks, economic insecurity, chronic illness, and the absence of age-friendly environments. The impacts extend beyond individual health, contributing to increased healthcare utilization, caregiver burden, and societal costs. Notably, there is a paucity of longitudinal data, culturally validated screening tools, and locally tested interventions. The public health implications are substantial, especially in a country where geriatric mental health is marginalized within national policy frameworks. The review calls for the development of a national aging policy that incorporates mental health, investment in primary care-based screening and support systems, community-based participatory interventions, and stigma-reduction campaigns. It also underscores the need for regionally tailored and gender-sensitive research. Addressing the mental health needs of Nigeria’s older adults is both a moral imperative and a developmental necessity.