community-dwelling-based survey in China to explore determinants for undetected dementia and depression in older adults. Method

people over the age of 60 years. At present, around 50 million people in the world are living with dementia, and an estimated 30 million older adults are living with depression. They represent two of the world’s biggest health problems and are increasingly a major public health challenge given that the world’s population is ageing. Both disorders are associated with poorer overall health, social function and healthcare outcomes, and increased mortality. However, these mental illnesses can be difficult to identify and often remain undetected, and possibly form barriers to care. Undetected dementia and depression levels vary among countries depending on social and cultural characteristics and health service provision. In the UK, O’Connor et al examined 208 patients aged over 75 years and observed that general practitioners (GPs) failed to identify 42% of those assessed as having dementia using the Cambridge Mental Disorders of the Elderly Examination. In Canada, Worrall & Moulton found that among 20 individuals with dementia (identified by the Canadian Mental Status Questionnaire) in rural community-dwelling residents aged 470 years, 15 patients (75%) were undetected in medical records. In Finland, Arve et al 9 found that GPs failed to detect depression in 58% of 109 patients aged 70 years. A failure to detect dementia and depression can cause delays in starting treatment, leading to patient suffering, disability and worsening of the prognosis. Despite the high risk of non-detection of dementia and depression in older adults, related risk factors are not well known. Knowledge relating to levels of underdetection is mainly derived from studies undertaken in high-income countries, with consequential problems in generalising findings to lowand middle-income countries (LMICs) across the world. There are few studies examining undetected dementia and depression in older adults in LMICs, where the majority of dementia and depression occurs. Studying an older population in LMICs may offer internationally applicable insights into the level and determinants of undetected dementia and depression and aid earlier diagnosis. In this paper we examine data from a large-scale community-dwelling-based survey in China to explore determinants for undetected dementia and depression in older adults.