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R A Marrie

Publications and source records attributed to R A Marrie.

8 recordsLinked to original sources
PubMed2006

Does multiple sclerosis-associated disability differ between races?

OBJECTIVE: To investigate differences in disability between African American and Caucasian patients with multiple sclerosis (MS) by comparing the relationship between current age and disability between races and by assessing the effect of adjustment for socioeconomic status (SES) on the associations. METHODS: The authors selected US participants from the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry with an age at symptom onset of 10 to 60 years, who reported their race as Caucasian or African American (n = 21,557). They classified participants as having mild, moderate, or severe disability in the domains of mobility, hand function, cognition, and vision using Patient Determined Disease Steps and Performance Scales and assessed the association of disability with race using polytomous logistic regression. RESULTS: Disability increased more rapidly with increasing disease duration in older patients, but there was no interaction between race and age. African Americans had increased odds of severe vs mild disability in all four domains (odds ratio [OR] [95% CI]: hand 1.35 [1.10 to 1.64]; vision 1.75 [1.37 to 2.27]; cognition 1.32 [1.04 to 1.67]; mobility 1.32 [1.11 to 1.56]). Adjustment for all covariates, including SES, attenuated these associations (OR [95% CI]: hand 1.27 [1.00 to 1.61]; vision 1.59 [1.19 to 2.08]; cognition 0.98 [0.74 to 1.30]; mobility 1.37 [1.11 to 1.67]). Lack of adjustment for SES produced stronger associations. After enrollment in NARCOMS, disability progression did not differ between the groups. CONCLUSIONS: African Americans experience greater multiple sclerosis-associated disability than Caucasians. Failure to account for socioeconomic status leads to overestimation of these differences. Disease progression is similar in African Americans and Caucasians after diagnosis.

Adolescent↗
PubMed2005

Changes in the ascertainment of multiple sclerosis.

OBJECTIVE: With diagnostic criteria alterations, increased MRI availability, and awareness of therapies, temporal changes in incidence and prevalence rates may occur, with an increase in the proportion of mildly affected persons diagnosed with multiple sclerosis (MS). The authors assessed temporal trends in the delay from symptom onset to diagnosis (DONDX), and determined whether the degree of disability at diagnosis differs by year of symptom onset (YONSET), using the NARCOMS Registry. METHODS: The authors selected US participants with an age at symptom onset of 10 to 60 years, and YONSET > or = 1980 (n = 16,581). The authors divided YONSET into 5-year groups and compared DONDX between groups using multivariate Cox regression. The authors classified participants enrolled within 2 years of diagnosis (n = 5,548) as having mild, moderate, or severe disability using Patient Determined Disease Steps, and assessed the association of disability with YONSET using polytomous logistic regression. RESULTS: DONDX decreased with later YONSET (r = -0.43, p < 0.0001). This association remained after adjustment for demographic factors in a multivariate Cox model. Later YONSET was associated with increased odds of having mild disability at diagnosis as compared to severe disability (OR = 1.10 per year; 1.09 to 1.11). CONCLUSION: The delay from symptom onset to diagnosis is steadily decreasing in MS. An increasing proportion of patients with MS have mild disability at diagnosis after accounting for confounders. As the effectiveness of therapies is influenced by disease duration, this has implications for comparison of treatment effects in modern clinical trials to earlier study results.

Adolescent↗
PubMed2004

Clinical characteristics of African Americans vs Caucasian Americans with multiple sclerosis.

BACKGROUND: African American (AA) individuals are thought to develop multiple sclerosis (MS) less frequently than Caucasian American (CA) individuals. OBJECTIVE: To compare the clinical characteristics of AA and CA patients with MS. METHODS: The clinical features of MS were compared in a large retrospective cohort of AA (n = 375) and CA (n = 427) subjects. RESULTS: The proportion of women to men was similar in AA and CA subjects (81% [AA] vs 77% [CA]; p = 0.122). There were no differences in the proportions of subjects with relapsing-remitting, secondary progressive, primary progressive, and progressive relapsing MS. The median time to diagnosis was 1 year after symptom onset in AA subjects and 2 years after symptom onset in CA subjects (p = 0.0013). The age at onset was approximately 2.5 years later in AA than CA subjects (33.7 vs 31.1 years; p = 0.0001). AA subjects presented with multisite signs and symptoms at disease onset more often than CA subjects (p = 0.018). Clinical involvement restricted to the optic nerves and spinal cord (opticospinal MS) occurred in 16.8% of AA patients compared with 7.9% of CA patients (p < 0.001). Transverse myelitis also occurred more frequently in AA subjects (28 vs 18%; p = 0.001). Survival analysis revealed that AA subjects were at higher risk for development of ambulatory disability than CA subjects. After adjusting for baseline variations and differences in therapeutic interventions, AAs were at 1.67-fold greater risk for requiring a cane to ambulate than CA patients (p < 0.001). There was a trend suggesting that AAs were also at greater risk for development of wheelchair dependency (p = 0.099). Adjusted Cox proportional hazard models showed that this effect was in part attributable to the older age at onset in AAs (p < 0.001). CONCLUSIONS: Compared with multiple sclerosis (MS) in Caucasian Americans, African American patients with MS have a greater likelihood of developing opticospinal MS and transverse myelitis and have a more aggressive disease course.

Adult↗
PubMed2001

Multiple sclerosis and varicella zoster virus infection: a review.

We have evaluated the epidemiological evidence for an aetiological role of varicella zoster virus (VZV) infection in the development of multiple sclerosis (MS). A MEDLINE search of the English language literature for 1965-99 identified 40 studies. These studies were categorized as seroepidemiological (13), case-control (23), historical cohort (2) or ecological (2). One study used both case-control and historical cohort methodologies. Studies were then classified according to methodological rigour, using criteria derived from published guidelines for the epidemiological study of MS. There was a large variability in the quality of evidence. The five studies with the best methodology failed to show an increased risk of MS associated with varicella or zoster infections. At the present time there is insufficient evidence to support an important aetiological role of VZV infection in the development of MS.

Adolescent↗
PubMed2001

Unusual imaging findings in progressive myoclonus epilepsy.

We describe a patient with progressive myoclonus epilepsy (PME), white matter hyperintensities in the corpus callosum, cerebral hemispheres, and left cerebral peduncle on magnetic resonance imaging (MRI), and positive oligoclonal bands. A phosphorus magnetic resonance spectrum was compatible with mitochondrial dysfunction. Abnormal white matter signals are not a feature of the known PME syndromes, although they occur in Leber's hereditary optic neuropathy (LHON). These abnormalities oriented the diagnosis toward mitochondrial disease.

Adult↗
PubMed2000

Multiple sclerosis and antecedent infections: a case-control study.

OBJECTIVES: To determine whether there is an excess of respiratory tract infections in the 5-week, 3-month, and 12-month periods before MS symptom onset and if there is an association between MS and a history of infectious mononucleosis (IM). BACKGROUND: The etiology of MS remains unknown, but infection is frequently suggested as a putative etiologic agent. Epidemiologic studies have produced inconsistent evidence for an etiologic role of respiratory tract infections (RTI) and IM in MS. METHODS: The authors performed a case-control study using the General Practice Research Database from the United Kingdom. There were 225 subjects with definite or probable MS, and 900 controls matched for age, sex, and physician practice. Using computerized patient records, the authors compared the mean rates of RTI per patient in the 5-week, 3-month, and 12-month periods before the date of onset of the first symptoms compatible with MS (index date). They also compared histories of IM. RESULTS: In all periods, an increased frequency of RTI was associated with a significantly increased risk of MS. A history of IM was associated with greater than five times the risk of MS (OR = 5.5 [95% CI 1.5 to 19.7]). CONCLUSIONS: These results support an association between a history of IM and subsequent MS. Respiratory tract infections may precipitate disease onset.

Adult↗
PubMed2000

Familial autoimmune myastenia gravis: four patients involving three generations.

BACKGROUND: Familial autoimmune myasthenia gravis (MG) is rare, although a genetic role for the development of autoimmune MG is suggested by concordance in monozygotic twins and the increased frequency of other autoimmune diseases in family members of myasthenics. METHODS: A patient with a family history of MG was evaluated in hospital. Relatives were interviewed and medical records examined for details regarding the diagnosis of MG in three other family members. RESULTS: The index case first experienced symptoms of MG at age 75 years. She developed generalized MG and required corticosteroids and immunosuppressive therapy to control her disease. Her father developed predominantly bulbar symptoms of MG at age 75 years. He died of complications experienced following a gastrostomy placed for continued difficulty swallowing. His brother developed similar symptoms of MG in his early 60s and died shortly after thymectomy. A 46-year-old nephew of the index case is also beginning to exhibit signs of generalized MG. Acetylcholine receptor antibodies were strongly positive in the index case and her nephew. (The assay was not available for her father and uncle). CONCLUSIONS: Four individuals in three successive generations had diagnoses of autoimmune MG. Study of familial cases such as these may clarify the contribution of genetic factors to the development of this disease.

Aged↗