The Mental Health of Older People Living in Nursing Homes in Northern Portugal: A Cross-Sectional Study Protocol.

: In Portugal, evidence regarding the mental health of institutionalized older people is limited, leaving this area poorly described and the mental health needs of this population largely unknown. This research aims to describe the mental health of older persons residing in nursing homes in Northern Portugal. : A cross-sectional study will be conducted. We estimate that 567 participants will be recruited through convenience sampling. Potential participants must live in nursing homes in Northern Portugal, be aged 65 years or older, and exhibit cognitive impairment at an initial or intermediate stage. Ten web survey questionnaires will be administered to the participants, including one sociodemographic and health questionnaire and nine mental health assessment instruments evaluating fear of falling; sleep quality; frailty; anxiety, depression, and stress; loneliness and social isolation; risk of acute confusion; cognition; emotional literacy; and perceived hope. Data will be analyzed by employing descriptive, cluster, inferential, and bivariate analyses, with multiple regression models included. The study and the research protocol were submitted to and approved by the Ethics Committee of a major public university in Northern Portugal (CEICVS 007/2025). This is a pioneering study in Portugal, representing the first attempt to assess the mental health of older nursing home residents. Our study will enhance the understanding of the mental and multifactorial health needs of this population through a comprehensive description of their mental health, and sociodemographic and health characteristics.