Latest trends in cancer incidence among UK South Asians in Leicester

Abstract

Using cancer registry data, we show that although South Asians have lower rates of cancer than the rest of the population, this is changing with age and time. Younger South Asians, particularly children, are at increased risk. While generally cancer rates have fallen over the last decade, they are increasing among South Asians. Cancer incidence rates in the UK have been reported to be much lower for South Asians (Indian, Pakistani and Bangladeshi) than the rest of the population (Winter et al, 1999). However, there has been little report on recent trends in cancer among South Asians in the UK. In order to explore recent cancer incidence trends, we used 1990 -1999 cancer registry data for Leicester, UK, a city where 22% of residents classified themselves as South Asian in the 1991 census. MATERIALS AND METHODSData were obtained from Trent Cancer Registry on all registrations of cancer diagnosed between 1 January 1990 and 31 December 1999, where the patient was a Leicester resident at diagnosis. Since routine ethnicity data were not available for all patients, individuals were classified as South Asian or non-South Asian based on forename and surname. Software was used to do this (Cummins et al, 1999), but accuracy was increased by visual inspection of the data. Deprivation is often a confounder in studies of ethnicity since they are closely related. There have been shown to be trends in incidence with deprivation for various cancer sites (Pollock and Vickers, 1997) so it was important to take account of deprivation in the analyses of cancer incidence. Therefore, the Townsend Index (Townsend et al, 1988) was used to assess the level of deprivation of the patient's area of residence. The local research ethics committee approved the study.Data were analysed for all cancers combined (all ages) and then for five common cancer sites (patients age 30 years and over): colorectal, head and neck, breast, lung and prostate. Electoral ward level population estimates were obtained from the 1991 census (by sex, ethnicity and 5-year age bands) and aggregated by deprivation tertile in order to calculate incidence rates. Variation in incidence rates by ethnicity, deprivation tertile, age and year of diagnosis (and any interactions between them) was explored using Poisson regression, separately for men and women. Firstly, a model was fitted to estimate the incidence rate ratio (IRR) for South Asians compared with non-South Asians for each age group, adjusting for deprivation tertile, and an interaction between ethnicity and age group was fitted to explore differential trends with age (Table 1). An interaction between time period (1990 -1994 and 1995 -1999) and ethnicity was then included to compare changes in incidence over time between South Asians and non-South Asians (Table 2). Interactions with deprivation were also explored. RESULTSOut of 12 128 cancer cases identified, 862 were classified as occurring in South Asians (7%). South Asians (median age 61.5 years) were younger than non-South Asians (median age 71.9 years).Overa...

Breast cancer outcomes in South Asian population of West Yorkshire

“…Over the period 1986 -1994, there was an increase in the number of registered South Asian patients with breast cancer. These results are consistent with other studies, showing increased incidence rates of breast cancer in South Asian women over time, while the rates decreased among non-Asian population Dos Santos Silva et al, 2003;Smith et al, 2003). These changes could be explained by the ageing population of South Asians, increased proportion of secondgeneration immigrants and significant differences in lifestyle and other exposures occurring in South Asian minority population in the UK.…”

“…This finding is likely to reflect the generally younger age of ethnic minorities in Britain (Office for National Statistics, 1996). It is consistent with observations in ethnic minority groups both in the UK and the USA (African-American women) (Coates et al, 1992;Elmore et al, 1998;Joslyn and West, 2000;Dos Santos Silva et al, 2003;Smith et al, 2003).…”

“…Nevertheless, it is our belief that this approach was the only feasible way of identifying South Asian patients in order to conduct this study. As an external validation of this approach, the standardised Incidence Rate Ratio was calculated 0.56 (95% CI 0.46 -0.66), which was found to be similar to the rate, reported by Smith et al (2003) The use of retrospective Registry data had the advantage of a large population-based database, but the disadvantage of not having complete staging information on all cases and no records of prognostic information, such as hormone receptor status. When examining survival, hormone receptor status is an important prognostic factor and the lack of that information may potentially lead to erroneous conclusions.…”

Information needs of Asian and White British cancer patients and their families in Leicestershire: a cross-sectional survey

“…The biggest minority population (25.7%) was described in the census as Indian, although some of these people would use a different name such as African/Asian to describe their origin. It has been predicted that by 2011, 50% of the population of Leicester will be of Asian origin (Rex, 1999).Cancer registration statistics collected between the start of 1990 and the end of 1999 for the city of Leicester showed that South Asian patients had a lower cancer incidence than non-South Asians (Smith et al, 2003a). When adjusted for age and socioeconomic deprivation, incidence rate ratio (IRR) was 0.61 for male and 0.75 for female population.…”

“…Cancer registration statistics collected between the start of 1990 and the end of 1999 for the city of Leicester showed that South Asian patients had a lower cancer incidence than non-South Asians (Smith et al, 2003a). When adjusted for age and socioeconomic deprivation, incidence rate ratio (IRR) was 0.61 for male and 0.75 for female population.…”