Multimorbidity in minority ethnic groups: A scoping review of the literature

Problem

Our understanding of the relationship between ethnicity and multimorbidity lags behind that of multimorbidity and socioeconomic status. Ethnicity, however, is likely to be as important a contributor to multimorbidity-related health inequalities as deprivation. To date, the evidence base for multimorbidity in minority ethnic populations is small. However, with increasing ethnic diversity and long-established ethnic populations ageing, we need evidence to ensure primary care services are appropriate to need.

Approach

We searched Medline and EMBASE, from 1996 to October 2019. Search terms included ethnicity, minority ethnic groups, multimorbidity. We also searched the reference lists of two previous reviews and the Academy of Medical Sciences multimorbidity report. A total of 531 papers were identified. These were double-screened and included if their principal focus was reporting on multimorbidity in ethnic/racial populations. Data extraction focused on: year of study; country of study; study design; number of participants; aim; key findings; definitions used for ethnicity/race; definitions for multimorbidity.

Findings

We identified 18 papers, all published since 2011. Of these, 12 were located in the US, 3 in the UK, 2 in Europe, 1 in New Zealand. In general, ethnicity/race was self-reported, although some US studies used computer algorithms to assign race. Multimorbidity was usually based on a count of conditions and defined as ≥2 long-term conditions, usually taken from a longer list of physical and mental health conditions. Most focused on multimorbidity prevalence in ethnic/racial populations, with little or no attention to condition clusters or health-related outcomes. US-based studies also focused on different communities to that in the UK, in particular Hispanic and Latino populations. Compared to the White majority population, the adjusted prevalence of multimorbidity was higher for Black populations and, in US studies, lower for Hispanic populations. In the US, the prevalence tended to be lower for Asian populations. In the UK, compared to the White population, multimorbidity prevalence was higher for South Asians. Two related US studies reported that multimorbidity starts earlier in minority ethnic groups than in White groups. One UK study suggested that disease clusters were different for White and non-White populations, with diabetes the most dominant condition in clusters in the White population, whereas depression and cancer dominated the cluster in the non-White population.

Consequences

There is little literature to draw on to understand the impact of multimorbidity in ethnic minority populations. Most of the published papers reported on prevalence, comparing it to the majority White population. Populations were often reported as a homogenous entity, e.g South Asians. There is almost no literature on onset or disease clusters, nor the impact on ethnic minority populations. In an increasingly diverse UK, primary care practitioners need much more information about multimorbidity in their minority ethnic patient populations.