Prevalence and uptake of HIV services among men who have sex with men in Northern Nigeria.

Chronic pain (CP), which is defined as persistent or recurrent pain over three months [], exerts an enormous personal and economic burden worldwide, affecting approximately 30% of the world’s population []. About half of these individuals experience multisite chronic pain (MCP), which involves two or more body sites [,]. Research has demonstrated that pain originating from a single site is frequently interrelated with pain in other sites, often evolving into MCP []. MCP is associated with a wide range of adverse physical, psychological, and functional outcomes and imposes substantial healthcare and societal burdens []. Targeted interventions are critical to mitigate the public health burden of MCP. Although previous research has revealed that pain most commonly co-occurred in mirrored contralateral sites [], studies on the pain patterns of MCP are still limited. It remains unclear whether pain patterns differ across populations, despite the established disparities in MCP prevalence among women [], older adults [], ethnic minorities [], and low-income groups []. Consequently, further investigation into pain co-occurrence patterns in MCP is warranted to improve our understanding of the distribution and interrelationships of pain sites. Nationally, CHARLS data from 2018 showed a 60.02% prevalence of CP among Chinese adults aged ≥45, rising to 66.84% in western China and 65.07% among ethnic minorities []. Notably, 90% of older CP patients in ethnic minority areas experienced MCP [], underscoring its high burden in western China’s ethnic minority regions. Yunnan Province, a less-developed region in western China characterized by substantial ethnic diversity, a large population residing in remote mountainous areas, limited healthcare access, and a high burden of musculoskeletal pain, provides a particularly relevant context for studying MCP among middle-aged and older adults [,]. Understanding MCP co-occurrence patterns in this population may help inform pain management strategies in similar underserved and low-resource settings.