Epidemiology of Multiple sclerosis in Saudi Arabia, a Descriptive study

doi:10.21203/rs.2.17183/v1

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Epidemiology of Multiple sclerosis in Saudi Arabia, a Descriptive study

https://doi.org/10.21203/rs.2.17183/v1

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Introduction In 2015, the first nationwide, multi-center MS registry was initiated in the Kingdom of Saudi Arabia with an objective to describe current epidemiology, disease patterns, and clinical characteristics of MS in Saudi Arabia. This article aims to report initial findings of the registry and report regional prevalence of MS.

Method The registry included all MS patients with confirmed MS diagnosis according to 2010 McDonald Criteria. It aimed to identify and recruit all healthcare institutions treating MS patients in the Kingdom, and collect data such as demographics, clinical characteristics (disease onset, diagnosis, disease course, relapse rate, and disability measures), family history, and treatments. All the included sites have obtained IRB/EC approvals for participating in the registry.

Results As of September 2018, the registry has included 20 hospitals from the different regions across the Kingdom and has collected comprehensive data on 2,516 patients from those hospitals, with mean age 33.42 (SD: 9.70) and 66.5% being females. The reported prevalence of MS for those hospitals is estimated to be 7.70/100,000 total population and 11.80/100,000 Saudi nationals. Assuming that the prevalence is the same across all the hospitals in the particular region, we projected the prevalence for total hospitals capable of diagnosing and treating MS and accordingly projected the total prevalence of MS as 40.40/100,000 total population and 61.95/100,000 Saudi nationals. The prevalence was reported 77.5% among people age <40 and below. The female to male ratio was 2:1. The prevalence was higher among female, young and educated individuals across all five regions of Saudi Arabia.

Conclusion The prevalence of MS has significantly increased in Saudi Arabia but is still much lower than western and other neighboring countries like Kuwait, Qatar, and the UAE. However, compared to the past rates, Saudi Arabia’s projected prevalence of MS through this national study is 40.40/100,000population, putting them above the low risk zone as per Kurtzke classification. The projected prevalence is estimated to be much higher among Saudi nationals only (61.95/100,000Saudi-nationals). The prevalence was higher among female, younger, and educated individuals. Further studies are needed to asses the risk factors associated with increased prevalence in Saudi Arabia.

Neurology

Epidemiology

Prevalence

Multiple Sclerosis

registry

Saudi Arabia

Multiple sclerosis is one of the most common inflammatory neurological disorders with the global prevalence of 33/100,000. Prevalence has increased substantially in many regions since 1990, especially in various low and middle income countries across the globe imposing a significant economical and health care burden. (1–3) MS is potentially a progressive disease of central nervous system that leads to life-long disabilities and impacting the productivity of individuals affected and patient and family quality of life. Many patients with multiple sclerosis enter a progressive phase of the disease one to two decades after onset. Common neurological manifestations include vision impairment, loss of co-ordination and balance, fatigue, pain, bladder dysfunction, cognitive dysfunction, numbness, weakness and mood changes. (4–5)

Pathophysiology of MS is complex and is considered as an autoimmune disease triggered by auto-reactive CD4 and helper T cells causing demyelination. However genetic and infectious factors have been reported by many studies (6–7). Genetic disposition is also reported for MS, females being more affected compared to males. (8) With respect to age, prevalence of MS increased after adolescence, reaching a peak between 25 and 35 years. Other environmental factors such as vitamin D levels, obesity, and certain early childhood exposure to infectious agents, smoking, and certain other modifiable risk factors are associated with increased risk of MS. (9)

As per Kurtzke classification, prevalence of MS in the Gulf region is marked as low-risk zone, however recent data have shown marked increased in the prevalence of MS, nearly 31–55 MS per 100,0000 individuals. (10) The increased prevalence in the Gulf region could be associated with change in lifestyle conditions, vitamin D deficiency and parental consanguinity as reported by few studies. (11, 12) However, the lack of a central MS registry and long term follow-up epidemiological studies, make it difficult to understand the actual prevalence and associated factors related to the increasing number of MS cases in the region.

Unlike neighboring Gulf countries (ex. UAE, Qatar, & Kuwait), the prevalence of MS was not as high in Saudi Arabia, and MS was not considered as a significant concern in the Kingdom compared to western and other gulf countries, mainly because the lack of data and underreporting of the cases. (11) In the period of 2015–2018, the first nationwide, multicenter MS registry was initiated in the Kingdom mainly with the objective to describe current epidemiology, disease patterns, and clinical characteristics of MS in Saudi Arabia. The data reported an increased prevalence of MS in the Kingdom, which in turn is alarming and warrants a public health action. (13)

This article aims to report initial findings of the national MS registry in Saudi Arabia with regards to the prevalence of MS which in turn would be a valuable repository of information on the characteristics and long term course of MS in the Kingdom. Reporting the actual burden of MS by using these cross sectional and longitudinal databases aim to offer significant information that can promote a better understanding of the prognosis and risk-factors, as well as serve as an essential guide for both socioeconomic and clinical decision-making. It offers insights into the progression and process of the disease, together with its effect on the morbidity, quality of life and functional status of the patients. Patients’ registries are, in general, a valuable source of information as they provide significant data about a disease/disorder that cannot be otherwise captured.

In 2015, a national MS registry was launched in Saudi Arabia to register all patients confirmed with Multiple Sclerosis diagnosis according 2010 McDonald Criteria. The registry managed by a steering committee (consisting of three main investigators) and a scientific committee (consisting of 10 neurologists from different sites across the different regions in the Kingdom). The study was carried out as a cross-sectional study, with an aim to identify and recruit all healthcare facilities in the Kingdom and collect disease-related data. All the sites included in the registry to date have obtained IRB/EC approvals for participating in the registry. Currently, 20 hospitals across the kingdom are participating in the registry (table 1).

Table 1: Total hospital across the KSA, hospital that treats MS and hospital participating in MS registry, Saudi Arabia

Regions	Total population (%)	Hospital treating MS patients	Hospitals included in registry
Western Region	10690445	30	7
Central Region	9640219	36	7
Eastern Region	4900325	22	4
Southern Region	4837837	9	2
Northern Region	2483510	8	0
Total “2017”	32552336	105	20

Data Collection:

The data was directly entered by participating physicians into a Web-based Application accessible through the internet in participating sites. Variables included in the registry were structured, discussed and approved by the two registry committees and workgroups (Steering and Scientific). Data collected include but not limited to demographics, clinical characteristics (disease onset, diagnosis, presentation of symptoms at onset, disease course, relapse rate, and disability measures), family history, and treatments.

Data Management and Cleaning:

Validation of different data was conducted at each of the sites. Missing data were checked, identified with appropriates codes during the analysis and have been indicated in the tables appropriately. Missing data was categorized for mandatory variables and non-mandatory variables. However, for applying test of significance, missing data was excluded.

Statistical Analysis:

The following is a general description of the planned statistical methods used for analysis of the data collected until 2018:

Frequency distribution tables are generated according to the regions. Continuous and discreet quantitative variables (age, time duration, etc.) are summarized in terms of descriptive statistics such as mean (Standard deviation) and Median (Inter quartile range) as per normality test. Categorical variables such as gender, educational status, and marital status are described as the total number and relative percentage of patients per response category. To evaluate the association between different categorical variables, bivariate analyses are also performed. To test for differences in the mean values (when the data followed normal distribution) between different strata, one way analysis of variance (ANOVA) is employed. If the data revealed statistical significance further inter comparisons amongst the groups is carried out and P-values is corrected by post hoc Bonferroni Method. Similarly, to compare the difference in the mean values between different strata, student t-test is employed. Chi square and Fisher exact test are reported for categorical variables. Data analysis was performed with statistics software SPSS 22.0. Statistical significance was set at p-value < 0.05. For estimating prevalence population for year 2017 has used.

As of September 2018, the registry has included 20 hospitals from the different regions across the Kingdom and has collected comprehensive disease-related data on 2,516 patients from those hospitals, with mean age 33.42(SD: 9.70) and 66.5% being female. The reported prevalence of MS in the included hospitals is 7.70/100,000 population. Assuming that the prevalence is the same across all the hospitals in each particular region, we estimated the prevalence for the total hospitals capable of diagnosing and treating MS. Finally, we projected the total prevalence of MS by keeping in consideration the population size in the particular region and total number of hospitals treating MS in that region, accordingly, the estimated overall prevalence was found to be 40.4/100,000 population. (Table 2) Prevalence of MS was higher for western region followed by central, eastern, northern and southern. A different trend of projected prevalence has been noticed with respect to regions, highest for central region followed by eastern, western, northern and southern.

Table 2: MS prevalence for Saudi Arabia

Regions	Total hospital (MS)	Included hospitals	MS patients from 20 hospital	Prevalence/ 100000 population	Projected prevalence/100000 population
Western Region	30	7	990	9.3	39.9
Central Region	36	7	866	9.0	46.3
Eastern Region	22	4	378	7.7	42.4
Southern Region	9	2	173	3.6	16.2
Northern Region*	8	0	109	4.4	35.2
Total “2017”	105	20	2516	7.7	40.4

Among Saudi nationals, the total prevalence of MS is estimated to be 11.80/100,000 per Saudi nationals, and the projected prevalence is estimated to be 61.95/100,000 per Saudi nationals. The prevalence was higher in western region followed by central, eastern, northern and southern regions. However, projected prevalence is estimated to be higher in central region followed by western, eastern, northern and southern regions. (Table 3)

Table3: Prevalence of MS among Saudi Nationals

Regions	Saudi nationals	MS patients from 20 hospital (Saudi Nationals)	Prevalence/ 100000 population	Projected prevalence/100000 population
Western Region	5892821	931	15.8	67.7
Central Region	5667865	833	14.7	75.6
Eastern Region	5892821	371	7.6	64.9
Southern Region	3777879	173	3.6	20.7
Northern Region*	1929435	107	5.5	44.0
Total “2017”	20408362	2415	11.8	61.95

The prevalence of MS was higher among females across all the regions (p value: 0.746). Of total 2516 patients’ information as per region was available for 2507 patients with some missing information, therefore, the analysis was done on available data only. 77.5% of the patients were 40 years of age or younger and the variance in age was significantly different among the regions with p value of 0.006. With respect to the educational level, majority were University graduates and post-graduates (57.4%) followed by high school (31.9%), primary school (9.4%) and illiterate only 1.3%. This trend in educational level was seen among all the regions. With respect to the employment, it was observed that 41.6% of the total cases were employed, 48.2% were unemployed, and 10.2% were students. Of all cases, majority were married (60.0%), followed by singles (36.3 %) and 3.6% divorced/widow(er). Level of education and occupation significantly differed across the regions with p value <0.001for both. (Table 4) Across all the regions, nearly 86.9% of the patients got education material at the time of diagnosis. Among the total referrals, more than half of the patients (54.2%) were referred by Government/public hospitals, private referrals were 28.2%, and personal referrals were the least and made 17.6%. The referral pattern, however, varied between the regions with p value <0.001 for all. The mean age of 1^st attack was 27.82(SD: 8.86) with significant difference between western and eastern and western and central regions with p value for Bonferroni 0.044 and 0.045 respectively. The mean number of previous relapse was 1.10(SD: 1.41). Lowest numbers were reported in east region compared to other regions with p value for Bonferroni of <0.001, and also a significant difference was found between the central and south regions with p value 0.023. The most common presenting symptom at first attack included muscle weakness (57.1%), followed by visual symptoms (48.2%) and sensory symptoms (47.3%) among all the cases in all the regions. Similar distribution was observed between the regions where majority had muscle weakness followed by visual symptoms. Among the total, majority of MS had undergone MRI investigation (98.4%) followed by Evoked potential (46.9%) and CSF (37.7%). Majority of the patients were diagnosed with relapsing remitting form of MS (92.6%), it varied between the regions from 90.3-94.4%. the Median EDS score was 1 (IQR 0-2.5) indicating that majority had no or minimal disability.

Table 4: Distribution of baseline characteristics among the patients across all the regions of KSA (n=2507)

Variable

Total

Western Region

Central Region

Eastern Region

Southern Region

Northern Region

Gender

Male

Female

839(33.5)

1668(66.5)

125(33.3)

250(66.7)

287(33.3)

575(66.7)

325(32.9)

663(67.1)

59(34.1)

114(65.9)

43(39.4)

66(60.6)

Age*

</=40

>40

1941(77.5)

565(22.5)

728(73.8)

259(26.2)

698(81.0)

164(19.0)

294(78.4)

81(21.6)

137(79.2)

36(20.8)

84(77.1)

25(22.9)

Education*

Illiterate

Primary

High school

University and above

32(1.3)

235(9.4)

798(31.9)

1434(57.4)

20(2.0)

106(9.4)

284(28.8)

577(58.5)

5(0.6)

68(7.9)

257(30.0)

527(61.5)

4(1.1)

27(7.2)

166(44.5)

176(47.2)

3(1.7)

21(12.1)

53(30.6)

96(55.5)

0(0.0)

13(11.9)

38(34.9)

58(53.2)

Occupation*

Employed

Unemployed

Student

1040(41.6)

1203(48.2)

56(10.2)

380(38.5)

516(52.3)

91(9.2)

382(44.6)

363(42.4)

112(13.1)

155(41.4)

189(50.6)

30(8.0)

72(41.6)

82(47.4)

19(11.0)

51(47.2)

53(49.1)

4(3.7)

Marital status*

Single

Divorced/widow(er)

Married

910(36.3)

91(3.6)

1504(60.0)

334(33.8)

35(3.5)

619(62.7)

327(38.0)

35(4.1)

498(57.9)

146(38.9)

11(2.9)

218(58.1)

72(41.6)

5(2.9)

96(55.5)

31(28.4)

5(4.6)

498(57.9)

Education Material*

Given

Not Given

1963(86.9)

297(13.1)

742(93.8)

49(6.2)

645(77.9)

183(22.1)

355(95.7)

16(4.3)

126(76.8)

38(23.2)

95(89.6)

11(10.4)

Age at 1^st attack (Mean SD)

27.82(8.86)

28.50(9.39)

27.29(8.22)

26.93(8.81)

27.54(8.81)

29.50(8.64)

No of previous relapse (Mean SD)

1.10(1.41)

1.20(1.45)

1.05(1.47)

0.70(1.09)

1.41(1.53)

1.32(1.13)

*Indicating missing data

* Patients referred to other regions. For calculating projected prevalence for northern region we assumed 109 patients were referred from a single hospital of northern region to other regions

Multiple sclerosis (MS) is one of the most commonly found autoimmune diseases that affect the central nervous system (CNS), and tends to affect adults during their most productive years. Generation of a disease registry is a systematic procedure for gathering data related to patients with certain conditions and diagnosis, or individuals who underwent certain procedures to help in tracking clinical care and outcomes. These registries are a valuable source for both, clinicians and policy makers. The registry provides real-world evidence on the actual burden of the disease, the quality and effectiveness of clinical practices, patient outcomes, and health care services utilization. It also allows patients’ identification, enhances care coordination and disease management.

Previously, the Gulf region was thought to have a low prevalence of MS, but recent data from the last few years have shown increased cases of MS in the region in general, including Saudi Arabia, with prevalence rates of MS cases ≥30/100,000. There are still no National or regional registries in the region to help understand the actual burden of the disease and reach an accurate estimate of the prevalence. In 2015, the first nationwide, multicenter MS registry was initiated in the Saudi Arabia with the objective to describe current epidemiology, disease patterns, and clinical characteristics of MS in Saudi Arabia. Through this article, we are reflecting the current prevalence of MS which is estimated as 7.70/100,000 population by using the registry data for 20 hospitals. However, by projecting the estimation on total Saudi population, the prevalence of MS is estimated as 40.40/100,000 Saudi population. The prevalence is estimated higher for central region followed by eastern, western, northern and southern. Moreover prevalence was higher among females, among young individuals, among educated and employed individual and among married across western, eastern, central, southern and northern region of Saudi Arabia.

The estimated prevalence in Saudi Arabia is lower than reported in the studies conducted in Kuwait (104.88 per 100,000 persons), Qatar (64.57 per 100, 00), UAE (57.09 per 100,000) and Iran (54.51 per 100,000). However, the prevalence among Saudi nationals only is comparable to prevalence reported in the above-mentioned studies (15–18) Moreover comparing to other western regions the prevalence in Saudi Arabia is low. The prevalence in other western countries is reported as high as 98.4 per 100,000, 106.6 per 100,000, 170.9 per 100,000 and 179.9 per 100,000 in central Italy, Italy, France, Columbia and Canada respectively.(19–22) The variation in the prevalence could be related to many factors for example genetic variation, certain environmental factors, role of ethnicity and certain variation in the methods followed in different studies. However the increased prevalence is consistently reported across different studies conducted globally and in neighboring countries. The female to male ratio in our study is 2:1 nearly similar to the two recent studies conducted in the MENA region, R. Alroughani et al. and Hamdiet. Al the female to male ratio was reported as 1.84:1 and 2.14: 1 respectively. (15, 23) The mean age at disease onset was 27.8years, similar to the reported overall estimate in a meta-analysis of 52 studies in the MENA region of 28.54 years (27.61–29.48 years). (24)

The prevalence reported in this paper should be concluded cautiously as the prevalence has been projected by assuming that the prevalence is same across all the hospitals this could have under or overestimated the projected prevalence as the actual rates are not known. This registry is able to collect data from 20 hospitals out of 105 hospitals treating MS population covering only 19% of hospitals. On discussing these data with the Ministry of Health (MOH) there is a work on progress to lunch a new longitudinal registry in 2020 with the support of MOH involving all hospitals in KSA. Moreover with the advancement in the diagnostic techniques and increase awareness the reporting of MS differs with time and that might affect the true prevalence of MS. However since the advent of this registry the diagnosis of MS remained standardized across the KSA thus it is highly unlikely that the rates of MS have been fluctuated drastically in the past years.

To conclude, the current/new Multiple sclerosis database (registry) in Saudi Arabia has been able to provide vital information on MS to inform the health care providers, healthcare planners, patients and the scientific community. The registry has been able to establish baseline epidemiological data on MS. The registry has scope to link up with population database and arrive at incidence and prevalence of the disease. The data obtained from a registry provides a foundation for understanding and evaluating the clustering and geography of MS, gender history and variances in the gender ratio of the disorder allowing future healthcare planning, and promotion of advocacy as well as support a wide array of research initiatives.

This article is the first step of reporting the current prevalence of MS in Saudi Arabia by reporting the findings of the MS registry. With the available data we can conclude that the projected prevalence of MS is 40.40/100,000 total population putting them above the low risk zone as per Kurtzke classification. However, the projected prevalence is much higher among Saudi nationals only that is 61.95/100,000 Saudi nationals only. The prevalence was higher among female, young individuals and educated individuals across all five regions of Saudi Arabia. Further studies are needed to study the risk factors associated with increased prevalence in Saudi Arabia.

Corresponding Authors

Aljumah, M.

Ethics approval and consent to participate:

The study was approved by the Ministry of Health and by Ethics Committee in each of the participating and included hospitals in the registry

Consent for publication

Also, individual participants in the study has provided a signed informed consent to participate in the study with the potential to publish research papers based on the aggregated and anonymous data collected by the registry.

Availability of data and materials

Data and relevant material is available upon request. However, access to the data is restricted to public and require appropriate approvals from the authorized and participating parties.

Conflict of Interest:

The authors declare that they have no conflict of interest related to this topic.

Funding:

This study was supported by grants from King Abdulaziz City for Science and Technology, grant # AT–34–438

Authors’ contributions

Authors have made significant contributions to the study design, data acquisition, analysis, and interpretation. They have read and approved the submitted version.

Acknowledgements

Not Applicable

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Epidemiology of Multiple sclerosis in Saudi Arabia, a Descriptive study

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Abstract

Introduction

Method

Data Collection:

Results

Discussion

Conclusion

Declarations

Corresponding Authors

Ethics approval and consent to participate:

Consent for publication

Availability of data and materials

Conflict of Interest:

Funding:

Authors’ contributions

Acknowledgements

References

Status:

Journal Publication

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