Poverty and health-related quality of life of people living in Hong Kong: comparison of individuals from low-income families and the general population.

Background: To assess health-related quality of life (HRQOL) among Chinese adults from low-income households in Hong Kong, and to explore any threshold of household income that impaired HRQOL.
Methods: A cross-sectional analysis was conducted on 298 adults from low-income families when they enrolled into a cohort study between 2012 and 2014. HRQOL was measured by the 12-item Short-Form Health Survey-version 2 (SF-12v2). Their mean SF-12v2 subscale and summary scores were compared with those of 596 age-sex-matched subjects randomly selected from a database of 2763 adults from the Hong Kong general population (ratio = 1:2). Multiple linear regressions were conducted to determine any association between monthly household income and HRQOL.
Results: Subjects from low-income households had significantly lower SF-12v2 bodily pain, general health, vitality and physical component summary (PCS) scores than the age-sex matched subjects from the general population. Subgroup analysis showed that a household income <50% of the median monthly household income in Hong Kong (HK$10 000 ≈ US$1290, i.e. poverty line in Hong Kong) was independently associated with poorer PCS and mental component summary (MCS) scores after adjustment for socio-demographics and co-morbidities.
Conclusion: Chinese adults from low-income households had poorer HRQOL, and <50% of the median monthly household income seems to be the threshold for impairment of both physical and mental HRQOL. The findings support the current definition of the poverty line.