Ethnic groups, geographical regions and MS
Non-parametric analysis of seasonality in birth and MS risk in second generation of migrants in Kuwait(26/08 14)
There are inconsistent reports about multiple sclerosis (MS) risk among migrants from low to high MS risk geographical regions. This study assessed the overall MS incidence and evaluated seasonality in birth and subsequent MS risk later in the life in second generation of migrants born and lived in Kuwait.
Methods: We assessed the overall and gender-specific MS risk in second generation of migrants born and lived in Kuwait between January 1, 1950 and April 30, 2013.
Data on migrant MS patients diagnosed and registered in Kuwait National MS Registry were used. Hewitt's non-parametric test was carried out to evaluate the seasonality in migrant MS births in comparison with the second generation migrant births in general population.
Results: During the study period, an overall risk of migrant MS births (per 100,000 non-Kuwaiti births in general population) as 23.8 (95% CI: 20.8 - 27.0).
Gender-specific MS risk showed that non-Kuwaiti female had statistically significant (p=0.003) higher risk (28.6; 95% CI: 24.2 - 33.7) than non-Kuwaiti males (18.7; 95% CI: 15.1-23.0). The month-specific distribution of migrant MS births compared with migrant births in general population did not differ significantly (2 goodness-of-fit test statistic=9.51, p=0.575).
Hewitt's non-parametric test revealed an evidence of slight but statistically non-significant (p=0.090) increased tendency of migrant MS births during September through February.
Conclusions: The proportion of migrant MS births (per 100,000 migrant births in general population) over the study period was 23.8 (95% CI: 20.8 - 27.0), which was statistically significantly higher than the previously reported Kuwaiti national MS births (16.2; 95% CI: 15.1-17.4) in Kuwait. Non-parametric analysis showed slight but statistically non-significant increased tendency of migrant MS births from September through February.
Knowledge of MS risk factors and how and when they act among genetically vulnerable individuals from gestation to early adulthood will help design prevention strategies.
Author: Saeed AkhtarRaed AlroughaniAhmad Al-ShammariJarrah Al-AbkalYasser Ayad
Credits/Source: BMC Neurology 2014, 14:170
Source: 7thSpace Interactive © 2014 7thSpace Interactive (26/08 14)
Clinical features and disability progression in multiple sclerosis in Tunisia: Do we really have a more aggressive disease course?
Sidhom Y, Damak M, Riahi A, Hizem Y, Mrissa R, Mhiri C, Gouider R.
BACKGROUND: Few epidemiological data are available on multiple sclerosis (MS) patients in North Africa (NA). Studies of immigrants from NA showed a more aggressive course compared to European patients.
OBJECTIVE: The aim of this study is to describe clinical and long term course characteristics of MS in Tunisia and to compare it to European cohorts.
METHOD: A total of 437 MS patients from three hospital based cohorts in Tunisia and having prospective follow up between 2010 and 2012 were analyzed. We considered as endpoints the time to reach EDSS scores of 3, 4 and 6 in the different clinical forms of MS and the beginning of a secondary progressive (SP) phase.
RESULTS: Sex ratio was 2.34. Mean age of onset was 30.3years. The course was relapsing-remitting (RR) in 91% of patients and primary progressive (PP) in 9%. The most frequent isolated onset symptoms were respectively motor (28%), optic neuritis (20%) and sensory (16%) dysfunction. Median time to SP onset was 19.1years. Median times from onset of multiple sclerosis to assignment of a score of 3, 4 and 6 were 8, 10.7 and 15years respectively. Benign form of MS represented 31.5%. Median interval from the onset of the disease to EDSS score of 3, 4 and 6 was shorter in PP-MS than in RR-MS. However, there was no difference between these two groups for the median time from the assignment of EDSS 4 to the assignment EDSS 6.
CONCLUSIONS: Our study shows that Tunisian MS patients have a quite similar clinical feature to European patients. Still, larger MS multicenter cohort studies in NA with longer follow-up duration could clearly respond to the issue.
Source: J Neurol Sci. 2014 Aug 15;343(1-2):110-4. doi: 10.1016/j.jns.2014.05.049. Epub 2014 Jun 2 & Pubmed PMID: 24980939 (25/07/14)
The purpose of this study was to determine the incidence of clinically isolated syndrome (CIS), a potential precursor of multiple sclerosis (MS), and whether it varies by race/ethnicity in a multi-ethnic, population-based cohort. We conducted a retrospective cohort study of over 9 million person-years of observation from the multi-ethnic, community-dwelling members of Kaiser Permanente Southern California Health Plan from January 1, 2008 to December 31, 2010.
Incidence of CIS and risk ratios comparing incidence rates between racial/ethnic groups were calculated using Poisson regression. We identified 468 newly diagnosed CIS cases that did not meet McDonald criteria for MS.
The average age at diagnosis was 39.0 years (range 2.7-85.8) and 68.8 % were women. The female preponderance was more pronounced among black (75.7 %) and Hispanics (70.5 %) than in white and Asian individuals with CIS (66.5 and 54.5 %, respectively; P = 0.14).
The most common presenting symptom in Hispanics was optic neuritis (P = 0.008), and in blacks, transverse myelitis (P = 0.07). Incidence of CIS was lower in Hispanics (3.8, 95 % CI 3.2-4.4, P < 0.0001) and Asians (2.4, 95 % CI 1.5-3.6, P < 0.0001) and similar in blacks (6.8, 95 % CI 5.3-8.5, P = 0.30) compared with whites (5.9, 95 % CI 5.1-6.7).
The incidence of CIS varies by race/ethnicity and sex in a similar pattern to MS. In addition, the clinical presentation of CIS varies by race/ethnicity. These findings strengthen the probability that the old belief that blacks have a decreased risk of MS is no longer true.
These findings highlight that studies that include minorities are likely to lead to important insights into the etiology and prognosis of CIS and MS.
Langer-Gould A, Brara SM, Beaber BE, Zhang JL.
Sources: J Neurol. 2014 Apr 29. [Epub ahead of print] & Pubmed PMID: 24777692 (02/05/14)
It's a disease that strikes down adults at their prime -- and it's found Ground Zero in Canada.
Multiple sclerosis afflicts Canadians at a rate that far outpaces any place else in the world, a new survey has found.
"It's really shocking … It is almost like a Canadian disease," said Karen Lee, of the Multiple Sclerosis Society of Canada.
Nearly 100,000 Canadians have the disease, a rate that's 28% higher than the country with the second-highest mark, Denmark, and nine times higher than the global average, according to the survey by the Multiple Sclerosis International Federation.
While Canadians are the most likely in the world to get the disease, they're waiting longer than most to get diagnosed, and no wonder -- Canada lags behind most developed countries when it comes to the number of neurologists and MRI machines.
There's no doubt speedy diagnosis and treatment play a big role in how many patients fare, said Lee, a neuroscientist who tracks research so the society can choose how to allocate the money it raises -- $12 million in 2013.
"The earlier the treatment, the better the prognosis, generally," she said.
In people with MS, their immune system attacks the sheath that insulates the body's central nervous system, causing damage that can leave victims unable to walk and suffering from physical and cognitive deficits.
Most MS sufferers can be treated with a range of medications that suppress the immune system, but doctors often have to try several to find which one works best for a patient.
When doctors quickly diagnose the disease and find the best treatment, patients fare better, experts say.
Just why Canadians are so afflicted has been the subject of debate and research has uncovered several theories. Among them: Canadians live so far from the equator, the sun is too low in the sky much of the year to cause our skin to make vitamin D; we may have earlier exposure to viruses that might play a role in triggering MS; Canadians may share a genetic predisposition to the disease; those who smoke appear at higher risk.
"We don't have an answer," said Dr. Christine Wolford, a professor of epidemiology and biostatistics at McGill University. She studied the prevalence of MS in the Americas in a study published last year in the journal Neuroepidemiology.
The search for answers has become more challenging because many factors are at play, both genetic and environmental, she said.
The Multiple Sclerosis International Federation first published a survey of MS rates in 2008 and Canada topped the list. Since then, the rate here has jumped another 18%.
Canadians shouldn't put too much stock in those exact numbers, since both here and across the globe, no one has done an adequate job precisely tracking MS, Wolford said.
But there's no doubt Canadians are more afflicted than others.
"Canada keeps coming up on top," she said.
THE MS TOP 10
(Disease prevalence per 100,000 population)
Czech Rep.: 160
-- Source: Multiple Sclerosis International Federation, World Health Organization
Source: THE TORONTO SUN COPYRIGHT © 2014 THE TORONTO SUN (02/01/14)
Multiple sclerosis is most often found in northern Europe, north America, Australia and New Zealand, all populated by European colonists.
In Britain, the numbers affected are highest in Scotland, far higher than they are in England or Wales, while the further north one goes in Scotland the more the figures rise: 229 per 100,000 in Aberdeen, 295 in Shetland, but 402 in Orkney.
“It has been suggested that the origins can be traced back to the Vikings who colonised those parts of northern Europe where MS is most pronounced and that ‘Viking genes’ can make people particularly susceptible to multiple sclerosis,” says the MS Society in Britain.
Today, however, the society is investigating another population group: the black Caribbeans who came to Britain after the second World War and their descendants, some of whom are displaying particular troubles coping with the often-crippling condition.
The disease progressed more quickly among a group of black Caribbeans compared with a white British group. Equally, the former group was also “more likely to experience higher levels of cognitive problems”, say researchers from King’s College and King’s College Hospital in London.
Multiple sclerosis is a neurological condition that affects the central nervous system. Globally, the numbers of sufferers is put at 2.5 million. In the UK, 100,000 people are affected, living with problems with balance and mobility, sight, along with fatigue.
“In interviews, black Caribbean people also more commonly spoke of being less able to deal with feelings of unresolved loss and confusion as a result of their rapidly advancing symptoms,” the researchers say.
Memory problems are mentioned again and again. “I always used to have a very good memory, now my memory’s very, very poor. Long-term memory’s fine, but my short- term memory is really, really bad,” said one 36-year-old man.
“I could have a talk with a friend today and arrange something for tomorrow and if I haven’t written it down, it will go straight out of my head.”
For now, possible explanations are few. “The reasons for the differences were not explored in this study, but could possibly include later perceptions of symptom onset, a genetic predisposition to more severe disease or less exposure to vitamin D,” says the research.
However, it has been known for decades that first-generation black Caribbeans – the so- called “Windies” – faced a relatively low risk from MS, while their children did “not seem to have a higher risk” than those who migrated as adults.
The findings though began to change in the late 1990s. Then, a study reported that living for 20 years in Britain raised the risk, which was “broadly consistent” with a belief that environment plays a key role.
The possible reasons to explain the numbers include lower socioeconomic status, a genetic predisposition to get a worse version of MS, should it come, and evidence that some black Caribbeans with MS are diagnosed later than other sections of the population.
Then there is vitamin D, with a belief that black Caribbeans suffer more than others from the shortage of sunlight in northern climes such as Britain between November and April – even though supplements can fill some of the gaps.
If the problems are clear, the solutions are not yet evident.
“Our findings demonstrated more aggressive MS disease among black Caribbeans despite a number of them being in receipt of disease-modifying therapy,” the team says in a study that was funded by the MS Society.
“More rapid disease progression leads to marked difficulties with ambulation, physical function and distress as a result of multiple losses.” The rising figures for black Caribbean MS sufferers poses issues about culturally sensitive care for the National Health Service, just as in the same way rising dementia rates do so among the elderly Irish community in Britain.
However, a distrustful attitude from minorities in general, not just black Caribbeans, to ethnic-based research can delay the discovery of problems. And some research can be skewed from the off because it is based upon “racially-based stereotypes”.
Last year, a study published by the British Medical Journal noted the cultural differences that exist between some, but not all, white British and black Caribbeans, with the latter more inclined to blame “fate or destiny” for their illness.
Urging officialdom to remember to “be mindful” of cultural differences, researchers call for appropriate investment in multi-ethnic services.If anything, the drift in Britain is away from that, not towards it.
Source: The Irish Times © 2013 THE IRISH TIMES (08/11/13)