A systematic review of morbidities suggestive of the multiple sclerosis prodrome

The association between multiple sclerosis and early psychiatric background

BACKGROUND

The exact cause of Multiple Sclerosis (MS) is unclear. Since its definition in the late 19th century, researchers have repeatedly suggested a connection between the disease and mental state. Studies have shown that mental symptoms tend to precede the initiation of the disease by up to ten years. However, the hypothesis that psychiatric issues might precede MS onset by longer periods has not been empirically established. This study seeks to fill this research gap. The current matched cohort study investigated the possibility that psychiatric conditions may precede the initiation of multiple sclerosis by 15 years or more METHODS: A retrospective analysis utilizing the electronic database of Clalit Health Services (CHS), Israel's largest HMO, compared a group of 9,533 MS-diagnosed female and male individuals with 28,599 non-MS matched controls RESULTS: Logistic regression analysis revealed a significant association (p < 0.001) between MS diagnosis and prior psychiatric conditions, indicating a 93% increased likelihood of psychiatric history among those later diagnosed with MS compared with those who were not CONCLUSIONS: The heightened probability of mental health issues preceding the onset of MS by extended durations suggests a potential etiological role in the development of MS, rather than solely representing a component of the prodromal stage of the disease. Limitations include the retrospective design and the need for prospective studies to validate these associations.

From progression to progress: The future of multiple sclerosis

Significant advances have been made in the diagnosis and treatment of multiple sclerosis in recent years yet challenges remain. The current classification of MS phenotypes according to disease activity and progression, for example, does not adequately reflect the underlying pathophysiological mechanisms that may be acting in an individual with MS at different time points. Thus, there is a need for clinicians to transition to a management approach based on the underlying pathophysiological mechanisms that drive disability in MS. A Canadian expert panel convened in January 2023 to discuss priorities for clinical discovery and scientific exploration that would help advance the field. Five key areas of focus included: identifying a mechanism-based disease classification system; developing biomarkers (imaging, fluid, digital) to identify pathologic processes; implementing a data-driven approach to integrate genetic/environmental risk factors, clinical findings, imaging and biomarker data, and patient-reported outcomes to better characterize the many factors associated with disability progression; utilizing precision-based treatment strategies to target different disease processes; and potentially preventing disease through Epstein-Barr virus (EBV) vaccination, counselling about environmental risk factors (e.g. obesity, exercise, vitamin D/sun exposure, smoking) and other measures. Many of the tools needed to meet these needs are currently available. Further work is required to validate emerging biomarkers and tailor treatment strategies to the needs of individual patients. The hope is that a more complete view of the individual's pathobiology will enable clinicians to usher in an era of truly personalized medicine, in which more informed treatment decisions throughout the disease course achieve better long-term outcomes.

[Imaging in headache]

Headache is worldwide one of the leading reasons to consult a general practitioner or a neurologist. In addition to the medical history and results of laboratory parameters, imaging represents one of the most important diagnostic steps. As there is a myriad of possible causes, it is nearly impossible to cover the whole spectrum of this topic. This article summarizes the most important morphological imaging findings and their pitfalls.

Identification and management of subclinical disease activity in early multiple sclerosis: a review

IMPORTANCE

Early treatment initiation in multiple sclerosis (MS) is crucial in preventing irreversible neurological damage and disability progression. The current assessment of disease activity relies on relapse rates and magnetic resonance imaging (MRI) lesion activity, but inclusion of other early, often "hidden," indicators of disease activity may describe a more comprehensive picture of MS.

OBSERVATIONS

Early indicators of MS disease activity other than relapses and MRI activity, such as cognitive impairment, brain atrophy, and fatigue, are not typically captured by routine disease monitoring. Furthermore, silent progression (neurological decline not clearly captured by standard methods) may occur undetected by relapse and MRI lesion activity monitoring. Consequently, patients considered to have no disease activity actually may have worsening disease, suggesting a need to revise MS management strategies with respect to timely initiation and escalation of disease-modifying therapy (DMT). Traditionally, first-line MS treatment starts with low- or moderate-efficacy therapies, before escalating to high-efficacy therapies (HETs) after evidence of breakthrough disease activity. However, multiple observational studies have shown that early initiation of HETs can prevent or reduce disability progression. Ongoing randomized clinical trials are comparing escalation and early HET approaches.

CONCLUSIONS AND RELEVANCE

There is an urgent need to reassess how MS disease activity and worsening are measured. A greater awareness of "hidden" indicators, potentially combined with biomarkers to reveal silent disease activity and neurodegeneration underlying MS, would provide a more complete picture of MS and allow for timely therapeutic intervention with HET or switching DMTs to address suboptimal treatment responses.

Prodromes in demyelinating disorders, amyotrophic lateral sclerosis, Parkinson disease, and Alzheimer's dementia

A prodrome is an early set of symptoms, which indicates the onset of a disease; these symptoms are often non-specific. Prodromal phases are now recognized in multiple central nervous system diseases. The depth of understanding of the prodromal phase varies across diseases, being more nascent for multiple sclerosis for example, than for Parkinson disease or Alzheimer's disease. Key challenges when identifying the prodromal phase of a disease include the lack of specificity of prodromal symptoms, and consequent need for accessible and informative biomarkers. Further, heterogeneity of the prodromal phase may be influenced by age, sex, genetics and other poorly understood factors. Nonetheless, recognition that an individual is in the prodromal phase of disease offers the opportunity for earlier diagnosis and with it the opportunity for earlier intervention.

Health, Wellness, and the Effect of Comorbidities on the Multiple Sclerosis Disease Course: Tackling the Modifiable

Multiple sclerosis (MS) is a disease of the central nervous system characterized by inflammatory demyelination and neurodegeneration. Numerous disease-modifying therapies for MS exist but are only partially effective, making it essential to optimize all factors that may influence the course of the disease. This includes conscientious management of both mental and physical comorbidities, as well as a comprehensive strategy for promoting wellness in patients with MS. Thoughtful engagement of those living with MS through shared decision making and involvement of a multidisciplinary team that includes primary care, relevant specialists, psychology, and rehabilitation is likely to lead to better outcomes.

Gastrointestinal conditions in the multiple sclerosis prodrome

OBJECTIVE

To investigate gastrointestinal (GI)-related physician visits and drug dispensations in the 5 years preceding a first recorded demyelinating event or multiple sclerosis (MS) onset.

METHODS

Using linked administrative and clinical data from British Columbia (1996-2013), Canada, we identified an administrative cohort via a validated algorithm (n = 6863), a clinical cohort diagnosed at a MS clinic (n = 966), and matched controls (administrative cohort: n = 31,865; clinical cohort: n = 4534). In each cohort, the 5 years before a first demyelinating event or MS symptom onset (i.e., index date) were examined. We compared rates of GI-related physician visits and risk of ≥1 GI-related dispensation between MS cases and controls using negative binomial and robust Poisson models. Sex differences were tested using interaction terms.

RESULTS

The administrative cohort MS cases had higher rates of physician visits related to gastritis and duodenitis (adjusted rate/risk ratio (aRR):1.42, 95% CI: 1.10-1.83) and diseases of the esophagus (aRR: 1.46, 95% CI: 1.06-2.02) prior to the index date. MS cases also had greater risk of at least one dispensation for several drug classes, including constipation-related (aRR: 1.82, 95% CI: 1.50-2.22), antiemetics/antinauseants (aRR: 1.64, 95% CI: 1.43-1.89), and propulsives (promotility drugs; aRR: 1.62, 95% CI: 1.47-1.79). Men had a disproportionally higher relative risk for propulsives than women (aRR: men = 2.32, 95% CI: 1.79-3.00; women = 1.54, 95% CI: 1.36-1.72). Several findings were similar in the smaller clinical cohort though none reached statistical significance.

INTERPRETATION

GI-related physician visits and drug dispensations were more common in the 5 years before the first demyelinating event versus matched controls. GI symptoms are a measurable feature of the prodromal or early phase of MS, with a sex difference evident.

Additive interaction between dietary inflammatory index and some key risk factors of multiple sclerosis: a population-based incident case-control study

BACKGROUND

Recently, dietary inflammatory index (DII) has been introduced as a significant risk factor for MS. We examined the interaction between dietary inflammatory index and some formerly demonstrated key risk factors of multiple sclerosis (MS).

MATERIAL AND METHODS

We conducted a population-based incident case-control study of 547 MS cases and 1057 controls. Multiplicative and additive interaction were assessed using interaction term in the logistic regression model and synergy index (SI), respectively.

RESULTS

Additive interaction was detected between DII and drug abuse (SI = 2.58; 95% CI: 1.14-5.82), gender (SI = 2.00; 95% CI: 1.39-2.87) and history of depression (SI = 1.68; 95% CI: 1.04-2.72) on the risk scale. The risk of MS in drug abusers with DII ≥ 0 was 10.4-times higher than that in non-drug abusers with DII < 0 (OR = 10.4, 95% CI: 5.12-21.02, P < 0.001). We also found that women with DII ≥ 0 had a 9.2 times larger risk compared with the men with DII < 0(OR = 9.2, 95% CI: 6.3-13.5, P < 0.001). Similarly, the risk of MS was remarkably higher in those with a history of depression and DII >0 (OR = 7.6, 95% CI: 5.1-11.5, P < 0.001). There was no evidence of multiplicative interaction between DII and the other risk factors of MS on the risk scale.

CONCLUSIONS

We identified additive interaction between DII and drug abuse, gender and history of depression on MS. Further studies are needed to understand the underlying mechanisms of these detected interactions.

Psychiatric Comorbidity During the Prodromal Period in Patients With Multiple Sclerosis

BACKGROUND AND OBJECTIVES

Psychiatric morbidity is common after a multiple sclerosis (MS) diagnosis. However, little is known about psychiatric comorbidity during the prodromal phase (before MS onset). To compare the prevalence and relative burden of psychiatric morbidity in individuals with MS with matched controls before MS onset.

METHODS

Using linked administrative and clinical data from British Columbia, Canada, we identified cases with MS through a validated algorithm or from neurologist-diagnosed MS clinic attendees. Cases were matched by age, sex, and geographical location with up to 5 general population controls. We identified psychiatric morbidity through a validated definition and determined its prevalence in cases/controls in the 5 years before the first demyelinating claim of cases with MS ("administrative cohort") or symptom onset ("clinical cohort") and estimated case/control prevalence ratios with 95% CIs. We also compared the yearly number of physician visits for psychiatric morbidity, visits to psychiatrists, psychiatric-related admissions, and psychotropic dispensations pre-MS onset in cases/controls regardless of whether psychiatric morbidity algorithm was fulfilled using negative binomial regression fitted through generalized estimating equations; results were reported as adjusted rate ratios with 95% CIs. We assessed yearly trends through interaction terms between cases/controls and each year pre-MS onset.

RESULTS

The administrative cohort comprised 6,863/31,865 cases/controls; the clinical cohort comprised 966/4,534 cases/controls. Over the entire 5-year period pre-MS onset, 28.0% (1,920/6,863) of cases and 14.9% (4,738/31,865) of controls (administrative cohort) had psychiatric morbidity, as did 22.0% (213/966) of clinical cases and 14.1% (638/4,534) controls. Psychiatric morbidity prevalence ratios ranged from 1.58; 95% CI 1.38-1.81 (clinical cohort) to 1.91; 95% CI 1.83-2.00 (administrative cohort). In the administrative cohort, health care use was higher for cases in each year pre-MS onset (all 95% CIs >1); physician visits were 78% higher in year 5 pre-MS onset and 124% 1 year before; visits to psychiatrists were 132% higher in year 5 and 146% in year 1; hospitalizations were 129% higher in year 5 and 197% in year 1; and prescription dispensations were 72% higher in year 5 and 100% in year 1. Results were not significant in the clinical cohort.

DISCUSSION

Psychiatric morbidity represents a significant burden before MS onset and may be a feature of the MS prodrome.

Adverse childhood experiences in early life increase the odds of depression among adults with multiple sclerosis

Background

Adverse childhood experiences are demonstrated risk factors for depression, a common co-morbidity of multiple sclerosis, but are understudied among people with multiple sclerosis.

Objective

Estimate the association between adverse childhood experiences and depression among 1,990 adults with multiple sclerosis.

Methods

Participants were members of Kaiser Permanente Northern California from two studies between 2006 and 2021 and were diagnosed with multiple sclerosis by a neurologist. Adverse childhood experiences were assessed using two instruments, including the Behavioral Risk Factor Surveillance System. Participants self-reported ever experiencing a major depressive episode. Meta-analysis random effects models and logistic regression were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) to assess the relationship between adverse childhood experiences and a history of depression across study samples. Adverse childhood experiences were expressed as any/none, individual events, and counts. Models adjusted for sex, birth year, race, and ethnicity.

Results

Exposure to any adverse childhood experiences increased the odds of depression in people with multiple sclerosis (OR: 1.71, 95% CI: 1.21-2.42). Several individual adverse childhood experiences were also strongly associated with depression, including "significant abuse or neglect" (OR: 2.79, 95% CI: 2.11-3.68).

Conclusion

Findings suggest that adverse childhood experiences are associated with depression among people with multiple sclerosis. Screening for depression should be done regularly, especially among people with multiple sclerosis with a history of adverse childhood experiences.

Patient-reported outcomes in multiple sclerosis: a prospective registry cohort study

Registries have the potential to tackle some of the current limitations in determining the long-term impact of multiple sclerosis. Online assessments using patient-reported outcomes can streamline follow-up enabling large-scale, long-term, cost-effective, home-based, and patient-focused data collection. However, registry data are sparsely sampled and the sensitivity of patient-reported outcomes relative to clinician-reported scales is unknown, making it hard to fully leverage their unique scope and scale to derive insights. This retrospective and prospective cohort study over 11 years involved 15 976 patients with multiple sclerosis from the United Kingdom Multiples Sclerosis Register. Primary outcomes were changes in two patient-reported outcomes: Multiple Sclerosis Impact Scale motor component, and Multiple Sclerosis Walking Scale. First, we investigated their validity in measuring the impact of physical disability in multiple sclerosis, by looking at their sensitivity to disease subtype and duration. We grouped the available records (91 351 for Multiple Sclerosis Impact Scale motor and 68 092 for Multiple Sclerosis Walking Scale) by these two factors, and statistically compared the resulting groups using a novel approach based on Monte Carlo permutation analysis that was designed to cope with the intrinsic sparsity of registry data. Next, we used the patient-reported outcomes to draw novel insights into the developmental time course of subtypes; in particular, the period preceding the transition from relapsing to progressive forms. We report a robust main effect of disease subtype on the patient-reported outcomes and interactions of disease subtype with duration (all P < 0.0001). Specifically, patient-reported outcomes worsen with disease duration for all subtypes (all P < 0.0001) apart from benign multiple sclerosis (Multiple Sclerosis Impact Scale motor: P = 0.796; Multiple Sclerosis Walking Scale: P = 0.983). Furthermore, the patient-reported outcomes of each subtype are statistically different from those of the other subtypes at all time bins (Multiple Sclerosis Impact Scale motor: all P < 0.05; Multiple Sclerosis Walking Scale: all P < 0.01) except when comparing relapsing-remitting multiple sclerosis with benign multiple sclerosis and primary progressive multiple sclerosis with secondary progressive multiple sclerosis. Notably, there were statistically significant differences between relapsing-remitting and progressive subtypes at disease onset. Critically, the patient-reported outcomes are sensitive to future transitions to progressive subtypes, with individuals who transition presenting with higher patient-reported outcomes in their relapsing-remitting phase compared to individuals who don't transition since onset (all P < 0.0001). Patient-reported outcomes capture different patterns of physical worsening over disease length and across subtypes; therefore, they are a valid tool to measure the physical impact of multiple sclerosis over the long-term and cost-effectively. Furthermore, more advanced physical disability manifests years before clinical detection of progressive subtypes, adding evidence to the presence of a multiple sclerosis prodrome.

Radiologically Isolated Syndrome and the Multiple Sclerosis Prodrome in Pediatrics: Early Features of the Spectrum of Demyelination

Radiologically isolated syndrome refers to the clinical scenario in which individuals have imaging concerning for multiple sclerosis and would otherwise satisfy radiographic dissemination in space criteria, but do not have any attributable signs or symptoms. Radiologically isolated syndrome has been increasingly recognized in the pediatric population and it is understood certain individuals will transition to a formal diagnosis of multiple sclerosis over time. This review aims to outline the available data within this unique population including the diagnostic criteria, epidemiology, risk factors associated with transitioning to multiple sclerosis, and the current therapeutic landscape. Radiologically isolated syndrome will also be positioned within a broader spectrum of demyelinating disease as recent data has pointed towards a likely prodromal phase that precedes a first clinical event and diagnosis of multiple sclerosis. Characterizing the radiographic features, clinical symptoms, and biomarkers that constitute this prodromal phase of multiple sclerosis would help identify patients who may most benefit from early intervention in the future.

Loss of Tyro3 causes anxiety-relevant behavioural changes in female mice

White-matter brain abnormalities have been found across a variety of psychiatric disorders. The extent of white matter pathology is proposed to be predictive of the severity of anxiety disorders. However, it is still unknown whether disruptions of white matter integrity precede, and are sufficient to give rise to, the behavioural symptoms. Interestingly, mood disturbances feature prominently in central demyelinating diseases such as multiple sclerosis. It is unclear whether the greater frequency of neuropsychiatric symptoms is linked to underlying neuropathology. In this study, we characterised male and female Tyro3 knockout (KO) mice using a variety of behavioural paradigms. Anxiety-related behaviours were assessed with the elevated-plus maze and light-dark box. Fear memory processing was assessed using fear conditioning and extinction paradigms. Finally, we assessed immobility time in the Porsolt swim test as a measure of depression-related behavioural despair. Surprisingly, loss of Tyro3 did not lead to manifestation of major shifts in baseline behaviour. We noted significant differences in habituation to novel environments and post-conditioning freezing levels of female Tyro3 KO mice, which are consistent with the female bias in anxiety disorders and could be indicative of maladaptive stress-responses. This study has demonstrated that white matter pathology related to a loss of Tyro3 is associated with pro-anxiety behavioural responses of female mice. Future studies could probe their contribution to increased risk for neuropsychiatric disorders when combined with stressful triggering events.

Prevalence of depression in amyotrophic lateral sclerosis/motor neuron disease: multi-attribute ascertainment and trajectories over 30 months

Objective: Evidence is equivocal about the prevalence of depression in amyotrophic lateral sclerosis (ALS). This study uses a multi-attribute ascertainment of the prevalence of depression and examines this prevalence over time. Methods: Patients with ALS were recruited into the Trajectories of Outcome in Neurological Conditions (TONiC-ALS) study. Caseness was identified by the Modified-Hospital Anxiety and Depression Scale (M-HADS). In addition, participants provided data on co-morbidities and medication use. A combination of the three was used to derive the estimate for the prevalence of depression, treated or untreated. Longitudinal data were analyzed by trajectory analysis of interval level M-HADS-Depression data. Results: Among 1120 participants, the mean age was 65.0 years (SD 10.7), 60.4% male, and the median duration since diagnosis was 9 months (IQR 4-24). Caseness of probable depression at baseline, defined by M-HADS-Depression, was 6.45% (95%CI: 5.1-8.0). Taken together with antidepressant medication and co-morbidity data, the prevalence of depression was 23.1% (95%CI: 20.7-25.6). Of those with depression, 17.8% were untreated. Trajectory analysis identified three groups, one of which contained the most cases; the level of depression for each group remained almost constant over time. Conclusion: Depression affects almost a quarter of those with ALS, largely confined to a single trajectory group. Prevalence estimates based on screening for current depressive symptoms substantially under-estimate the population experiencing depression. Future prevalence studies should differentiate data based on current symptoms from those including treated patients. Both have their place in assessing depression and the response by the health care system, including medication, depending upon the hypothesis under test.

Multiple sclerosis and migraine: Links, management and implications

Multiple sclerosis (MS) is a chronic inflammatory disease leading to multifocal neuronal demyelination and axonal damage in the central nervous system (CNS). MS symptoms vary widely but typically do not include headaches. A large spectrum of headaches manifestations was reported as comorbidities in MS and results in additional disability. Migraine, tension-type headache and cluster headache are the most frequently reported primary headache syndromes in patients with MS (pwMS). Secondary causes of headache should be excluded (cerebral vein thrombosis, CNS or systemic infection, cervical and/or cranial trauma, headaches associated with psychiatric disorders, medication overuse headache, etc.) in this particular population. A careful medical history and general and neurological examinations and sometimes further investigations may be needed to rule out secondary headache syndromes. In pwMS, the headache could be an adverse effect of the disease-modifying therapies or a complication of pain medication overuse prescribed to relieve other causes of pain related to MS (neuropathic pain, mechanical pain, pain associated with spasticity, etc.). Migraine-type headache occurs in pwMS more frequently than in the general population. It can precede the disease onset, be associated with relapses, or appear during the MS course. A predominance of brainstem inflammatory lesions is described on magnetic resonance imaging (MRI) in MS patients with migraine. The relationship between both conditions remains unclear. Migraine and MS occur in the same demographic groups with similar background factors, including gender, hormonal status, and psychological features (anxiety, depression, stress). An early diagnosis and adequate treatment of migraine in MS patients are important to improve their quality of life. In this review, we focus on the relationship between MS and Migraine, discuss the differential diagnoses of migraine in pwMS, and describe its management in this particular context.

Sex and age differences in the Multiple Sclerosis prodrome

Background and objectives

Little is known of the potential sex and age differences in the MS prodrome. We investigated sex and age differences in healthcare utilization during the MS prodrome.

Methods

This was a population-based matched cohort study linking administrative and clinical data from British Columbia, Canada (population = 5 million). MS cases in the 5 years preceding a first demyelinating event ("administrative cohort;" n = 6,863) or MS symptom onset ("clinical cohort;" n = 966) were compared to age-, sex- and geographically-matched controls (n = 31,865/4,534). Negative binomial and modified Poisson models were used to compare the rates of physician visits and hospitalizations per international classification of diseases chapter, and prescriptions filled per drug class, between MS cases and controls across sex and age-groups (< 30, 30-49, ≥50 years).

Results

In the administrative cohort, males with MS had a higher relative rate for genitourinary-related visits (males: adjusted Rate Ratio (aRR) = 1.65, females: aRR = 1.19, likelihood ratio test P = 0.02) and antivertigo prescriptions (males: aRR = 4.72, females: aRR = 3.01 P < 0.01). Injury and infection-related hospitalizations were relatively more frequent for ≥50-year-olds (injuries < 30/30-49/≥50: aRR = 1.16/1.39/2.12, P < 0.01; infections 30-49/≥50: aRR = 1.43/2.72, P = 0.03), while sensory-related visits and cardiovascular prescriptions were relatively more common in younger persons (sensory 30-49/≥50: aRR = 1.67/1.45, P = 0.03; cardiovascular < 30/30-49/≥50: aRR = 1.56/1.39/1.18, P < 0.01). General practitioner visits were relatively more frequent in males (males: aRR = 1.63, females: aRR = 1.40, P < 0.01) and ≥50-year-olds (< 30/≥50: aRR = 1.32/1.55, P = 0.02), while differences in ophthalmologist visits were disproportionally larger among younger persons, < 50-years-old (< 30/30-49/≥50: aRR = 2.25/2.20/1.55, P < 0.01). None of the sex and age-related differences in the smaller clinical cohort reached significance (P ≥ 0.05).

Discussion

Sex and age-specific differences in healthcare use were observed in the 5 years before MS onset. Findings demonstrate fundamental heterogeneity in the MS prodromal presentation.

From the prodromal stage of multiple sclerosis to disease prevention

A prodrome is an early set of signs or symptoms that indicate the onset of a disease before more typical symptoms develop. Prodromal stages are well recognized in some neurological and immune-mediated diseases such as Parkinson disease, schizophrenia, type 1 diabetes mellitus and rheumatoid arthritis. Emerging evidence indicates that a prodromal stage exists in multiple sclerosis (MS), raising the possibility of intervention at this stage to delay or prevent the development of classical MS. However, much remains unclear about the prodromal stage of MS and considerable research is needed to fully characterize the prodrome and develop standardized criteria to reliably identify individuals with prodromal MS who are at high risk of progressing to a diagnosis of MS. In this Roadmap, we draw on work in other diseases to propose a disease framework for MS that incorporates the prodromal stage, and set out key steps and considerations needed in future research to fully characterize the MS prodrome, identify early disease markers and develop standardized criteria that will enable reliable identification of individuals with prodromal MS, thereby facilitating trials of interventions to slow or stop progression beyond the prodrome.

Association of pregnancies with risk of multiple sclerosis

Background:

Pregnancies have an impact on the disease course of multiple sclerosis (MS), but their relationship with MS risk is yet unclear.

Objective:

To determine the relationships of pregnancies and gynecological diagnoses with MS risk.

Methods:

In this retrospective case–control study, we assessed differences in gynecological International Classification of Diseases, 10th Revision (ICD-10) code recording rates between women with MS (n = 5720), Crohn’s disease (n = 6280), or psoriasis (n = 40,555) and women without these autoimmune diseases (n = 26,729) in the 5 years before diagnosis.

Results:

Twenty-eight ICD-10 codes were recorded less frequently for women with MS as compared to women without autoimmune disease, 18 of which are pregnancy-related. After adjustment for pregnancies, all codes unrelated to pregnancies were still negatively associated with MS. In a sensitivity analysis excluding women with evidence for possible demyelinating events before diagnosis, all associations were more pronounced. In comparison to women with psoriasis, most associations could be confirmed; that was not true in comparison to women with Crohn’s disease.

Conclusion:

Our findings provide evidence for a possible protective effect of pregnancies on MS risk likely independent of or in addition to a previously suggested reversed causality. The negative associations of gynecological disorders with disease risk need further investigation. The associations might be shared by different autoimmune diseases.

The Multiple Sclerosis Prodrome: Evidence to Action

A growing body of work points toward the existence of a clinically symptomatic prodromal phase in multiple sclerosis (MS) that might span 5–10 years or more. A prodrome is an early set of signs or symptoms predating the onset of classical disease, which in turn predates a definitive diagnosis. Evidence for a prodromal phase in MS could have major implications for prevention, earlier recognition and treatment, as well as an improved disease course or prognosis. This Perspective provides a succinct overview of the recent advances in our understanding of the MS prodrome and current key challenges. Many of the MS prodromal features characterized thus far are non-specific and are common in the general population; no single feature alone is sufficient to identify an individual with prodromal MS. Biomarkers may increase specificity and accuracy for detecting individuals in the MS prodromal phase, but are yet to be discovered or formally validated. Progress made in the elucidation of prodromal phases in other neurological and immune-mediated diseases suggests that these barriers can be overcome. Therefore, while knowledge of a prodromal phase in MS remains nascent, how best to move from the rapidly growing evidence to research-related action is critical. Immediate implications include refining the concept of the MS continuum to include a prodromal phase. This will help inform the true “at risk” period when considering exposures that might cause MS. Major long-term implications include the earlier recognition of MS, improved prognosis, through earlier disease management, and the future possibility of MS disease prevention.

The multiple sclerosis prodrome

A prodrome is an early set of signs, symptoms or other findings that occur before the onset of typical symptoms of a disease. Prodromal phases are well recognized in several neurological and inflammatory diseases, but the possibility of a prodrome in multiple sclerosis (MS) has received relatively little attention until the past few years. In this Perspective, we summarize what is currently known about the MS prodrome, including its possible duration, clinical features and potential biomarkers. We also consider what insights and lessons can be learned from knowledge of and research into the prodromal phases of other diseases. A better understanding of the MS prodrome could have profound clinical implications as it could enable earlier recognition of MS and earlier initiation of treatments that reduce relapse rates and long-term disability. Knowledge of the MS prodrome could also affect research into the causes of MS, and putative risk factors must be re-evaluated in light of the MS prodrome. We conclude by outlining the major knowledge gaps and propose future initiatives.

Defining the prodromal phase of multiple sclerosis based on healthcare access in a Portuguese population - ProdMS study

BACKGROUND

Multiple sclerosis (MS) is a chronic immune-mediated disease of the central nervous system. Prodromal symptoms and higher healthcare use have been suggested in patients who later develop MS.

OBJECTIVES

Assess the healthcare utilization pattern of relapsing-remitting MS (RRMS) patients in the five years prior to MS diagnosis.

METHODS

Retrospective, multicentric study. Demographic and clinical data, drug prescriptions and diagnostic tests were collected from electronic health records five-years previous to MS diagnosis and compared with national data.

RESULTS

Included 168 patients, 112 (66.7%) female, median age 34±11 years. The mean number of healthcare use per patient per year was 3.14±2,69, most of them in primary healthcare (47%). Most frequent symptoms were musculoskeletal (22%), gastrointestinal (17%), sensitive (14%) and sensory organs (14%). Median number of diagnostic tests per patient was 6 (IQR 7), and drug prescriptions per patient was 6 (IQR 9). Most frequently prescribed drugs were analgesic/anti-inflammatories, antibiotics and anxiolytics and there was a high request rate of MRIs.

CONCLUSION

RRMS patients had a high frequency of healthcare utilization when compared to national data. This supports the current evidence showing a prodromal phase in MS.

Systematic Assessment of Medical Diagnoses Preceding the First Diagnosis of Multiple Sclerosis

OBJECTIVE

To explore the occurrence of diseases and symptoms in the 5 years before diagnosis in patients with multiple sclerosis (MS) in a case-control study.

METHODS

Using ambulatory claims data, we systematically assessed differences in the occurrence of diseases and symptoms in the 5 years before first diagnosis in patients with MS (n = 10,262) compared to patients with 2 other autoimmune diseases, Crohn disease (n = 15,502) and psoriasis (n = 98,432), and individuals without these diseases (n = 73,430).

RESULTS

Forty-three ICD-10 codes were recorded more frequently for patients with MS before diagnosis compared to controls without autoimmune disease. Many of these findings were confirmed in a comparison to the other control groups. A high proportion of these ICD-10 codes represent symptoms suggestive of demyelinating events or other neurologic diagnoses. In a sensitivity analysis excluding patients with such recordings before first diagnosis, no association remained significant. Seven ICD-10 codes were associated with lower odds ratios of MS, 4 of which represent upper respiratory tract infections. Here, the relations with MS were even more pronounced in the sensitivity analysis.

CONCLUSIONS

Our analyses suggest that patients with MS are frequently not diagnosed at their first demyelinating event but often years later. Symptoms and physician encounters before MS diagnosis seem to be related to already ongoing disease rather than a prodrome. The observed association of upper respiratory tract infections with lower odds ratios of MS diagnosis suggests a link between protection from infection and MS that, however, needs to be validated and further investigated.

Insights into the Pathophysiology of Psychiatric Symptoms in Central Nervous System Disorders: Implications for Early and Differential Diagnosis

Different psychopathological manifestations, such as affective, psychotic, obsessive-compulsive symptoms, and impulse control disturbances, may occur in most central nervous system (CNS) disorders including neurodegenerative and neuroinflammatory diseases. Psychiatric symptoms often represent the clinical onset of such disorders, thus potentially leading to misdiagnosis, delay in treatment, and a worse outcome. In this review, psychiatric symptoms observed along the course of several neurological diseases, namely Alzheimer’s disease, fronto-temporal dementia, Parkinson’s disease, Huntington’s disease, and multiple sclerosis, are discussed, as well as the involved brain circuits and molecular/synaptic alterations. Special attention has been paid to the emerging role of fluid biomarkers in early detection of these neurodegenerative diseases. The frequent occurrence of psychiatric symptoms in neurological diseases, even as the first clinical manifestations, should prompt neurologists and psychiatrists to share a common clinico-biological background and a coordinated diagnostic approach.