Bradyphrenia and Tachyphrenia in Idiopathic Parkinsonism Appear, in Part, Iatrogenic: An Observational Study with Systematic Review Background

We question whether bradyphrenia, slowing of cognitive processing not explained by depression or a global cognitive assessment, is a nosological entity in idiopathic parkinsonism (IP). The time taken to break contact of an index finger with a touch-sensitive plate was measured, with and without a warning in the alerting signal as to which side the imperative would indicate, in 77 people diagnosed with IP and in 124 people without an IP diagnosis. The ability to utilise a warning, measured by the difference between loge-transformed reaction times (unwarned minus warned), was termed 'cognitive efficiency'. It was approximately normally distributed. A questionnaire on self- and partner perception of proband's bradyphrenia was applied. A multivariable model showed that those prescribed levodopa were less cognitively efficient (mean -5.2 (CI -9.5, -1.0)% per 300 mg/day, p = 0.02), but those prescribed the anti-muscarinic trihexyphenidyl were more efficient (14.7 (0.2, 31.3)% per 4 mg/day, p < 0.05) and those prescribed monoamine oxidase-B inhibitor (MAOBI) tended to be more efficient (8.3 (0.0, 17.4)%, p = 0.07). The variance in efficiency was greater within IP (F-test, p = 0.01 adjusted for any demographic covariates: coefficient of variation, with and without IP, 0.68 and 0.46, respectively), but not so after adjustment for anti-parkinsonian medication (p = 0.13: coefficient of variation 0.62). The within-participant follow-up time, a median of 4.8 (interquartile range 3.1, 5.5) years (101 participants), did not influence efficiency, irrespective of IP status. Perception of bradyphrenia did not usefully predict efficiency. We conclude that both bradyphrenia and 'tachyphrenia' in IP appear to have iatrogenic components, of clinically important size, related to the dose of antiparkinsonian medication. Levodopa is the most commonly prescribed first-line medication: co-prescribing a MAOBI may circumvent its associated bradyphrenia. The previously reported greater efficiency associated with (low-dose) anti-muscarinic was confirmed.

Faecal metabolite deficit, gut inflammation and diet in Parkinson's disease: Integrative analysis indicates inflammatory response syndrome

BACKGROUND

Gut-brain axis is widely implicated in the pathophysiology of Parkinson's disease (PD). We take an integrated approach to considering the gut as a target for disease-modifying intervention, using continuous measurements of disease facets irrespective of diagnostic divide.

METHODS

We characterised 77 participants with diagnosed-PD, 113 without, by dietary/exogenous substance intake, faecal metabolome, intestinal inflammation, serum cytokines/chemokines, clinical phenotype including colonic transit time. Complete-linkage hierarchical cluster analysis of metabolites discriminant for PD-status was performed.

RESULTS

Longer colonic transit was linked to deficits in faecal short-chain-fatty acids outside PD, to a 'tryptophan-containing metabolite cluster' overall. Phenotypic cluster analysis aggregated colonic transit with brady/hypokinesia, tremor, sleep disorder and dysosmia, each individually associated with tryptophan-cluster deficit. Overall, a faster pulse was associated with deficits in a metabolite cluster including benzoic acid and an imidazole-ring compound (anti-fungals) and vitamin B3 (anti-inflammatory) and with higher serum CCL20 (chemotactic for lymphocytes/dendritic cells towards mucosal epithelium). The faster pulse in PD was irrespective of postural hypotension. The benzoic acid-cluster deficit was linked to (well-recognised) lower caffeine and alcohol intakes, tryptophan-cluster deficit to higher maltose intake. Free-sugar intake was increased in PD, maltose intake being 63% higher (p = .001). Faecal calprotectin was 44% (95% CI 5%, 98%) greater in PD [p = .001, adjusted for proton-pump inhibitors (p = .001)], with 16% of PD-probands exceeding a cut-point for clinically significant inflammation compatible with inflammatory bowel disease. Higher maltose intake was associated with exceeding this calprotectin cut-point.

CONCLUSIONS

Emerging picture is of (i) clinical phenotype being described by deficits in microbial metabolites essential to gut health; (ii) intestinal inflammation; (iii) a systemic inflammatory response syndrome.

Role of Helicobacters in Neuropsychiatric Disease: A Systematic Review in Idiopathic Parkinsonism

Interest in an aetiopathogenic role for Helicobacter in neuropsychiatric diseases started with idiopathic parkinsonism (IP), where the cardinal signs can be assessed objectively. This systematic review, using an EMBASE database search, addresses Oxford Centre for Evidence-Based Medicine based questions on the inter-relationship of Helicobacter and IP, the benefits of eradicating Helicobacter in IP and the outcome of not treating. The search strategy was based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines: 21 of 204 articles met the inclusion criteria. The results show that the assumption that any benefit of Helicobacter eradication results from improved levodopa bioavailability is unjustified. The inter-relationship between Helicobacter and IP is well-established. H. pylori virulence markers (associated with autoimmunity and immune tolerance) influence the risk, severity and progression of IP. The birth cohort effect for virulence marker antibodies, seen in controls, is obliterated in IP, suggesting causality. Successful H. pylori eradication in IP is disease-modifying (even in anti-parkinsonian treatment-naïve patients) but not preventive. Hypokinesia regresses with eradication and overall motor severity lessens. Eradication may influence gastrointestinal microbiota adversely, unlocking the next stage in the natural history, the development of rigidity. Failed eradication worsens hypokinesia, as does the presence/persistence of H. pylori at molecular level only. Adequate prognostic assessment of the consequences of not treating Helicobacter, for IP, is prevented by a short follow-up. We conclude that Helicobacter is a pathophysiological driver of IP.

Helicobacter suis Is Associated With Mortality in Parkinson's Disease

Helicobacter pylori has been implicated in the pathogenesis of Parkinson's disease (PD). Its eradication, in a randomized placebo-controlled trial, improved PD hypokinesia. Helicobacter species zoonosis might explain excess mortality from PD and non-Hodgkin lymphoma in livestock, but not arable, farmers. Indeed, Helicobacter is causally-associated with gastric lymphoma. We have previously shown that the relative-frequency, H. suis to H. pylori, was 10-times greater in 60 PD-patients than in 256 controls. We now go on to evaluate the pathological significance of H. suis, detected in gastric-biopsy DNA-extracts by ureA-based species-specific qPCR, validated by amplicon sequencing. The methodology had been cross-validated by a carR-based PCR. The pathological significance is put in context of H. pylori detection [urea-breath-test (UBT) with biopsy-culture, and, if negative, PCR], and the potential reservoir in pigs. Here, we explore, in these 60 PD-patients, associations of H. suis status with all-cause-mortality, and with orthostatic cardiovascular and blood profiling. H. suis had been detected in 19 of the 60 PD-patients on one or more occasion, only two (with co-existent H. pylori) being UBT positive. We found that the hazard-of-death (age-at-diagnosis- and gender-adjusted) was 12 (95% CI 1,103) times greater (likelihood-ratio test, P = 0.005) with H. suis-positivity (6/19) than with negativity (2/40: one lost to follow-up). UBT-values did not influence the hazard. H. suis-positivity was associated with lower standing mean-arterial-pressure [6 (1, 11) mmHg], H. pylori-positivity having no effect. The lower total lymphocyte count with H. pylori-positivity [-8 (-1, -14) %] was not seen with H. suis, where T-cell counts were higher [24 (2, 52) %]. Regarding the potential zoonotic reservoir in the UK, Helicobacter-like-organism frequency was determined in freshly-slaughtered pigs, nature ascertained by sequencing. Organisms immunostaining for Helicobacter, with corkscrew morphology typical of non-H. pylori Helicobacter, were seen in 47% of 111 pig-antra. We conclude that H. suis is associated with all-cause-mortality in PD and has a potential zoonotic reservoir.

Performance testing in rehabilitation: influence of context and cognitive function on mobility

The accuracy of routine information on the response of a patient to rehabilitation was questioned. At the multidisciplinary ward round there may be on the one hand an inhibitory effect on the patient's performance due to the presence of a large team, but on the other reluctance of nurses and therapists to concede that all their efforts may only have maintained status quo. We present a randomised, controlled, crossover study of the effect of the ward round on a test of the ability to stand, walk a fixed distance, turn and sit down. Surprisingly, performance was not inhibited by the round: the 20 patients studied performed the test with equal skill, but greater speed, on the round than in a more private context. Cognitive function had a greater influence on the amount of help needed in standing and sitting safely, than on ability to walk and turn independently.

Quantifying rigidity of Parkinson's disease in relation to laxative treatment: a service evaluation

Aim

To estimate whether laxatives prescribed for constipation in Parkinson's disease (PD) could moderate rigidity. Constipation predates diagnosis of PD by decades. Deposition of misfolded protein may begin in the gut, driven by dysbiosis. Successive antimicrobial exposures are associated with cumulative increase in rigidity, and rigidity has biological gradients on circulating leukocyte‐subset counts.

Methods

Retrospective service evaluation, in a gut/brain axis clinic, yielded an interrupted time series, relating maintenance laxative and other medication to rigidity, in consecutive outpatients identified by inclusion and exclusion criteria. Objective assessment of rigidity was used to bring greater sensitivity to change, validated against subjective gold standard (UPDRS).

Results

There were 1493 measurements of torque required to extend (flexor rigidity) and flex (extensor rigidity) the forearm in 79 PD patients over 374 person‐years. Both were strongly associated with UPDRS (P < 0.001 and P = 0.008, respectively). Before exhibition of laxative, flexor rigidity increased by 6% (95% CI 1, 10) per year, plateauing at −2% (−4, 1) per year after, with no shift at initiation. Change in slope was significant (P = 0.002), and manifest in those naïve to antiparkinsonian medication. The change was replicated for individual laxative classes (bulk, osmotic, enterokinetic). There was no temporal change in extensor rigidity. Limited experience with a quanylate cyclase‐C receptor agonist (17 patients, 6 person‐years) indicated a large and significant step down in flexor and extensor rigidity, of 19% (1, 34) and 16% (6, 24) respectively (P = 0.04 and <0.001).

Conclusions

Maintenance laxative usage was associated with apparent stemming of the temporal increase in rigidity in PD, adding to indicative evidence of a continuing role of gastrointestinal dysbiosis in pathogenesis.

Peripheral aetiopathogenic drivers and mediators of Parkinson's disease and co-morbidities: role of gastrointestinal microbiota

We seek an aetiopathogenic model for the spectrum of Parkinson's disease (PD), functional bowel disease, depression and cognitive impairment. The adopted concept is that systemic immuno-inflammatory processes mediate neuro-inflammation. The model would be based on phenotype, exposome (including gastrointestinal microbiome), milieu (immuno-inflammatory and metabolome), human genetics and their interactions. It would enable a patient's position, to be understood in terms of drivers, perpetuators and mediators, and a future position, with and without intervention, predicted. Even the cardinal facets of PD may have different drivers: halting one may allow escape down subordinate pathways. Peptic ulceration is prodromal to PD. In our randomised placebo-controlled trial, hypokinesia improved over the year following biopsy-proven Helicobacter pylori eradication and rigidity worsened. This was independent of any (stable, long t½) antiparkinsonian medication. There are pointers to an autoimmune process: for example, surveillance-confirmed hypokinesia effect was indication specific. During surveillance, successive antimicrobial courses, other than for Helicobacter, were associated with cumulative increase in rigidity. Exhibiting laxatives appeared to stem the overall temporal increase, despite antiparkinsonian medication, in rigidity. Thus, intestinal dysbiosis may be a major source of bystander neuronal damage. There are biological gradients of objective measures of PD facets on circulating inflammatory markers and leucocyte subset counts. Moreover, lactulose hydrogen breath test positivity for small-intestinal bacterial overgrowth (present in two thirds of PD patients) is associated with the same subsets: higher natural killer and total CD4+ counts and lower neutrophils. With greater aetiopathogenic understanding, relatively low cost and on-the-shelf medication could have a major impact. A new generation of animal models, based on the gut microbiome, is envisaged.

Significantly higher frequency of Helicobacter suis in patients with idiopathic parkinsonism than in control patients

BACKGROUND

There is increased proportional mortality from Parkinson's disease amongst livestock farmers. The hypokinesia of Parkinson's disease has been linked to Helicobacter pylori. H. suis is the most common zoonotic helicobacter in man.

AIM

To compare the frequency of H. suis, relative to H. pylori, in gastric biopsies of patients with idiopathic parkinsonism (IP) and controls from gastroenterology services.

METHODS

DNA extracts, archived at a Helicobacter Reference Laboratory, from IP patient and gastroenterology service biopsies were examined anonymously for H. suis, using species-specific RT-PCR.

RESULTS

Relative risk of having H. suis in 60 IP patients compared with 256 controls was 10 times greater than that of having H. pylori. In patients with IP and controls, respectively, frequencies of H. suis were 27 (exact binomial 95% C.I. 15, 38) and 2 (0, 3)%, and of H. pylori, 28 (17, 40) and 16 (12, 21)%. Excess of H. suis in IP held when only the antral or corporal biopsy was considered. Of 16 IP patients with H. suis, 11 were from 19 with proven H. pylori eradication, 3 from 17 pre-H. pylori eradication, 2 from 24 H. pylori culture/PCR-negative. Frequency was different between groups (P = 0.001), greatest where H. pylori had been eradicated. Even without known exposure to anti-H. pylori therapy, H. suis was more frequent in IP patients (5/41) than in controls (1/155) (P = 0.002). Partial multilocus sequence typing confirmed that strains from IP patients (6) and control (1) differed from RT-PCR standard strain.

CONCLUSIONS

Greater frequency of H. suis in idiopathic parkinsonism appears exaggerated following H. pylori eradication. Multilocus sequence testing comparison with porcine strains may clarify whether transmission is from pigs/porcine products or of human-adapted, H. suis-like, bacteria.

Antimicrobial surveillance in idiopathic parkinsonism: indication-specific improvement in hypokinesia following Helicobacter pylori eradication and non-specific effect of antimicrobials for other indications in worsening rigidity

BACKGROUND

Following Helicobacter pylori eradication in a placebo-controlled trial, the hypokinesia of idiopathic parkinsonism improved but flexor rigidity worsened.

METHODS

We surveyed the effect of all antimicrobial prescriptions in 66 patients with idiopathic parkinsonism over a median of 1.9 (interquartile range 0.4, 3.5) years. Initial Helicobacter screening was followed (where positive) by gastric biopsy. Serial lactulose hydrogen breath tests (364 tests) for small intestinal bacterial overgrowth monitored the need to encourage fluid intake and bulk/osmotic laxatives. We measured hypokinesia (401 assessments of mean stride length at free walking speed in 58 patients) and upper limb flexor rigidity (396 assessments in 49).

RESULTS

Following successful H. pylori eradication (12 cases) but not failed (2), stride increased in entire group (including those receiving levodopa), core group (those receiving only longer-t½ antiparkinsonian medication or untreated) and untreated (p = .001 each case). The effect was greater with less antiparkinsonian medication (19 (95% CI, 14, 25) cm/year in untreated). Flexor rigidity was unchanged. Following antimicrobials for other indications (75 courses), hypokinesia was unchanged. However, flexor rigidity increased cumulatively. It increased in core group only after a first course (by (10 (0, 20)%/year, p = .05)), but then in entire, core and untreated after a second course (18 (6, 31), 33 (19, 48) and 29 (12, 48)%/year respectively; p = .002, .001 and .001) and further still after a third (17 (2, 34), 23 (8, 41) and 38 (15, 65)%/year; p = .02, .003 and .001). Initially, 40/66 were lactulose hydrogen breath test positive. Odds for positivity fell with time (by 59 (46, 75)%/year, p = .001) and tended to be lower with Helicobacter positivity (28 (8, 104)%, p = .06), but were unrelated to other antimicrobial interventions.

CONCLUSIONS

Improved hypokinesia following antimicrobials appeared unique to Helicobacter eradication. Rigidity increased following successive antimicrobial exposures for other indications, despite diminishing lactulose hydrogen breath test positivity.

Leukocyte-subset counts in idiopathic parkinsonism provide clues to a pathogenic pathway involving small intestinal bacterial overgrowth. A surveillance study

BACKGROUND

Following Helicobacter pylori eradication in idiopathic parkinsonism (IP), hypokinesia improved but flexor-rigidity increased. Small intestinal bacterial-overgrowth (SIBO) is a candidate driver of the rigidity: hydrogen-breath-test-positivity is common in IP and case histories suggest that Helicobacter keeps SIBO at bay.

METHODS

In a surveillance study, we explore relationships of IP-facets to peripheral immune/inflammatory-activation, in light of presence/absence of Helicobacter infection (urea-breath- and/or stool-antigen-test: positivity confirmed by gastric-biopsy) and hydrogen-breath-test status for SIBO (positivity: >20 ppm increment, 2 consecutive 15-min readings, within 2h of 25G lactulose). We question whether any relationships found between facets and blood leukocyte subset counts stand in patients free from anti-parkinsonian drugs, and are robust enough to defy fluctuations in performance consequent on short t½ therapy.

RESULTS

Of 51 IP-probands, 36 had current or past Helicobacter infection on entry, 25 having undergone successful eradication (median 3.4 years before). Thirty-four were hydrogen-breath-test-positive initially, 42 at sometime (343 tests) during surveillance (2.8 years). Hydrogen-breath-test-positivity was associated inversely with Helicobacter-positivity (OR 0.20 (95% CI 0.04, 0.99), p<0.05).In 38 patients (untreated (17) or on stable long-t½ IP-medication), the higher the natural-killer count, the shorter stride, slower gait and greater flexor-rigidity (by mean 49 (14, 85) mm, 54 (3, 104) mm.s-1, 89 (2, 177) Nm.10-3, per 100 cells.μl-1 increment, p=0.007, 0.04 & 0.04 respectively, adjusted for patient characteristics). T-helper count was inversely associated with flexor-rigidity before (p=0.01) and after adjustment for natural-killer count (-36(-63, -10) Nm.10-3 per 100 cells.μl-1, p=0.007). Neutrophil count was inversely associated with tremor (visual analogue scale, p=0.01). Effect-sizes were independent of IP-medication, and not masked by including 13 patients receiving levodopa (except natural-killer count on flexor-rigidity). Cellular associations held after allowing for potentially confounding effect of hydrogen-breath-test or Helicobacter status. Moreover, additional reduction in stride and speed (68 (24, 112) mm & 103 (38, 168) mm.s-1, each p=0.002) was seen with Helicobacter-positivity. Hydrogen-breath-test-positivity, itself, was associated with higher natural-killer and T-helper counts, lower neutrophils (p=0.005, 0.02 & 0.008).

CONCLUSION

We propose a rigidity-associated subordinate pathway, flagged by a higher natural-killer count, tempered by a higher T-helper, against which Helicobacter protects by keeping SIBO at bay.

Prescribing aids for gentamicin

1 A nomogram and a digital computer program have been developed to calculate dosage schedules of gentamicin for individual patients. The minimum input data consist of the patients' age, sex, body weight and serum creatinine concentration. 2 These prescribing aids have been evaluated in 36 patients with severe Gram negative infections. Renal function ranged from normal to complete anuria. Nomogram dosage schedules gave serum concentrations of gentamicin within the chosen therapeutic limits. Physician dosage schedules gave serum concentrations which sometimes exceeded and sometimes fell below these limits. The validity of the computer program was demonstrated by its ability to predict serum concentrations of gentamicin whatever the dosage schedule. 3 Half the patients recovered from the bacterial infection but seven remained infected and eleven died. Pseudomonas aeruginosa was the most difficult organism to eradicate. 4 Four of the patients who survived developed ataxia and two developed hearing loss at high frequencies. The risk of ototoxicity was a function of mean trough serum gentamicin concentration and duration of treatment. Ototoxicity was only detected in patients with serum creatinine concentrations above 3 mg/100 ml who tended to have higher trough concentrations. When treatment was prolonged beyond 8-10 days the risk of ototoxicity was increased without evidence of further substantial therapeutic benefit.

Towards defining a rigidity-associated pathogenic pathway in idiopathic parkinsonism

Helicobacter pylori eradication has a differential effect on the facets of idiopathic parkinsonism (IP): brady/hypokinesia improves, but rigidity worsens. Small intestinal bacterial overgrowth is common in IP and has been described as a sequel to Helicobacter eradication. The hyperhomocysteinaemia of IP is, in part, explained by serum vitamin B(12), but the concentration is not explained by Helicobacter status. Moreover, Helicobacter-associated gastric atrophy is uncommon in IP. However, overgrowth both increases B(12) utilization and provides a source of inflammation to drive homocysteine production. It is not a bystander event in IP: clouds of lysosomes are seen in duodenal enterocytes. Its candidature for causality of a rigidity-associated pathway is circumstantial: there are biological gradients of rigidity on natural killer and T-helper blood counts, both being higher with hydrogen breath test positivity for overgrowth.

Differential effect of Helicobacter pylori eradication on time-trends in brady/hypokinesia and rigidity in idiopathic parkinsonism

BACKGROUND

We examine the effect of eradicating Helicobacter in idiopathic parkinsonism (IP). Marked deterioration, where eradication-therapy failed, prompted an interim report in the first 20 probands to reach de-blinding. The null-hypothesis, "eradication has no effect on principal outcome, mean stride length at free-walking speed," was rejected. We report on study completion in all 30 who had commenced post-treatment assessments.

METHODS

This is a randomized, placebo-controlled, parallel-group efficacy study of eradicating biopsy-proven (culture and/or organism on histopathology) Helicobacter pylori infection on the time course of facets of IP, in probands taking no, or stable long-t(1/2), anti-parkinsonian medication. Persistent infection at de-blinding (scheduled 1-year post-treatment) led to open active eradication-treatment.

RESULTS

Stride length improved (73 (95% CI 14-131) mm/year, p = .01) in favor of "successful" blinded active over placebo, irrespective of anti-parkinsonian medication, and despite worsening upper limb flexor rigidity (237 (57-416) Nm x 10(-3)/year, p = .01). This differential effect was echoed following open active, post-placebo. Gait did not deteriorate in year 2 and 3 post-eradication. Anti-nuclear antibody was present in all four proven (two by molecular microbiology only) eradication failures. In the remainder, it marked poorer response during the year after eradication therapy, possibly indicating residual "low-density" infection. We illustrate the importance of eradicating low-density infection, detected only by molecular microbiology, in a proband not receiving anti-parkinsonian medication. Stride length improved (424 (379-468) mm for 15 months post-eradication, p = .001), correction of deficit continuing to 3.4 years. Flexor rigidity increased before hydrogen-breath-test positivity for small intestinal bacterial overgrowth (208 (28-388) Nm x 10(-3), p = .02), increased further during (171 (67-274), p = .001) (15-31 months), and decreased (136 (6-267), p = .04) after restoration of negativity (32-41 months).

CONCLUSION

Helicobacter is an arbiter of progression, independent of infection-load.

Helicobacter hypothesis for idiopathic parkinsonism: before and beyond

We challenge the concept of idiopathic parkinsonism (IP) as inevitably progressive neurodegeneration, proposing a natural history of sequential microbial insults with predisposing host response. Proof-of-principle that infection can contribute to IP was provided by case studies and a placebo-controlled efficacy study of Helicobacter eradication. "Malignant" IP appears converted to "benign", but marked deterioration accompanies failure. Similar benefit on brady/hypokinesia from eradicating "low-density" infection favors autoimmunity. Although a minority of UK probands are urea breath test positive for Helicobacter, the predicted probability of having the parkinsonian label depends on the serum H. pylori antibody profile, with clinically relevant gradients between this "discriminant index" and disease burden and progression. In IP, H. pylori antibodies discriminate for persistently abnormal bowel function, and specific abnormal duodenal enterocyte mitochondrial morphology is described in relation to H. pylori infection. Slow intestinal transit manifests as constipation from the prodrome. Diarrhea may flag secondary small-intestinal bacterial overgrowth. This, coupled with genetically determined intense inflammatory response, might explain evolution from brady/hypokinetic to rigidity-predominant parkinsonism.

Role of inflammation in gastrointestinal tract in aetiology and pathogenesis of idiopathic parkinsonism

Idiopathic parkinsonism (IP) is a common disorder, conventionally regarded as neurodegenerative. Its cardinal features, poverty and slowness of movement, muscle rigidity, postural abnormality and a characteristic tremor, are associated with loss of dopaminergic neurones in the substantia nigra of the brain. Genetic factors explain only a minority of cases, and a common toxic environmental insult remains elusive. We propose that IP is a systemic disorder resulting from a ubiquitous peripheral infection, and that only the tip of the iceberg comes to diagnosis. There is evidence for inflammatory/immune activation peripherally and in the brain. We have used statistical modelling to explore links with non-specific and specific systemic markers of inflammation/infection in IP probands, and explore whether their partners and siblings have a frank or pre-presentation parkinsonian state. Critical to this approach is continuous objective measures of the facets of IP. Hypotheses on causality and mechanism are based on the statistical models. There is pathological and clinical evidence for direct involvement of the gastrointestinal tract in IP. The candidacy of Helicobacter pylori infection as a trigger event or driving infection is relatively high. We have found that eliminating infection in late parkinsonism with cachexia, a stage usually considered intractable, can result in a U-turn. However, eradication therapy may not provide a complete solution. Persistence of antibody against cytotoxin-associated antigen (CagA), increases the predicted probability of being labelled as having parkinsonism. Evidence for autoimmunity and immunocompromise is used to build schemes for the natural history. We conclude that current classifications of neuropsychiatric disease may not prove the best with respect to defining sub-clinical disease, prophylaxis or halting progression.

Role of chronic infection and inflammation in the gastrointestinal tract in the etiology and pathogenesis of idiopathic parkinsonism. Part 3: predicted probability and gradients of severity of idiopathic parkinsonism based on H. pylori antibody profile

BACKGROUND

Eradicating Helicobacter may convert rapidly progressive idiopathic parkinsonism to quieter disease, however only a minority of probands have evidence of current infection.

AIM

To explore the cross-sectional fit of parkinsonism as an extra-alimentary consequence of Helicobacter pylori, using the serum antibody profile.

METHODS

A discriminant index for parkinsonism was based on the Western Blot pattern of IgG antibodies against electrophoretically separated H. pylori antigens in 124 subjects with idiopathic parkinsonism, 196 without. In parkinsonism, association was assessed between index and 1, anthropometric measures; 2, current and 3, increase over 4 years in hypokinetic and psychomotor/psychometric disability; and 4, a global score of current severity.

RESULTS

Predicted probability of being labeled parkinsonian was greatest with cytotoxin-associated-gene-product (CagA) positivity and vacuolating-toxin negativity (p = .03 and .004, respectively, for antibody-age interactions), and urease-B negativity (p = .03, irrespective of age). In this circumstance, the odds for parkinsonism increased fivefold by age 80 years (p = .001). Helicobacter status, according to anti-urease enzyme-linked immunosorbent assay (ELISA), did not complement the model. Gradients, of clinically relevant size, were found between index and disease burden, despite the potentially confounding effect of antiparkinsonian medication. The higher the index 1, the worse was posture, as gauged by forward displacement of occiput (p = .04), 2, the shorter mean stride-length (p = .003), longer reaction time (= .002) and lesser cognitive efficiency (= .03), 3, the greater their deterioration (p = .006, .002, and .03 respectively), and 4, the greater the overall severity of parkinsonism (< .001).

CONCLUSION

The apparent importance of H. pylori in the etiology/pathogenesis of idiopathic parkinsonism is not confined to those with evidence of current infection.

Role of chronic infection and inflammation in the gastrointestinal tract in the etiology and pathogenesis of idiopathic parkinsonism. Part 1: eradication of Helicobacter in the cachexia of idiopathic parkinsonism

BACKGROUND

Neuronal damage in idiopathic parkinsonism may be in response to ubiquitous occult infection. Since peptic ulceration is prodromal, Helicobacter is a prime candidate.

AIM

To consider the candidature of Helicobacter in parkinsonism with cachexia.

METHODS

We explore the relationship between being underweight and inflammatory products in 124 subjects with idiopathic parkinsonism and 195 controls, and present the first case-series evidence of efficacy of Helicobacter eradication, in parkinsonism advanced to the stage of cachexia.

RESULTS

Association of a low body mass index with circulating interleukin-6 was specific to parkinsonism (p = .002), unlike that with antibodies against Helicobacter vacuolating-toxin and cytotoxicity-associated gene product (p < .04). Marked reversibility in both cachexia and disability of idiopathic parkinsonism followed Helicobacter heilmannii eradication in one case, Helicobacter pylori eradication in another, follow-up being > or = 3.5 years. The latter presented with postprandial bloating, and persistent nausea: following eradication, radioisotope gastric-emptying returned towards normal, and upper abdominal symptoms regressed. Reversibility of their cachexia/disability contrasts with the outcome of anti-Helicobacter therapy where eradication repeatedly failed (one case), and in non-Helicobacter gastritis (three cases). Anti-parkinsonian medication remained constant. Intestinal absorption and barrier function were normal in all.

CONCLUSION

Categorization, according to presence or absence of Helicobacter infection, was a useful therapeutic tool in late idiopathic parkinsonism.

Role of chronic infection and inflammation in the gastrointestinal tract in the etiology and pathogenesis of idiopathic parkinsonism. Part 2: response of facets of clinical idiopathic parkinsonism to Helicobacter pylori eradication. A randomized, double-blind, placebo-controlled efficacy study

BACKGROUND

Links between etiology/pathogenesis of neuropsychiatric disease and infection are increasingly recognized.

AIM

Proof-of-principle that infection contributes to idiopathic parkinsonism.

METHODS

Randomized, double-blind, placebo-controlled efficacy study of proven Helicobacter pylori eradication on the time course of facets of parkinsonism. Intervention was 1 week's triple eradication therapy/placebos. Routine deblinding at 1 year (those still infected received open-active), with follow-up to 5 years post-eradication. Primary outcome was mean stride length at free-walking speed, sample size 56 for a difference, active vs. placebo, of 3/4 (between-subject standard deviation). Recruitment of subjects with idiopathic parkinsonism and H. pylori infection was stopped at 31, because of marked deterioration with eradication failure. Interim analysis was made in the 20 who had reached deblinding, seven of whom were receiving antiparkinsonian medication (long-t(1/2), evenly spaced) which remained unchanged.

RESULTS

Improvement in stride-length, on active (n = 9) vs. placebo (11), exceeded size of effect on which the sample size was calculated when analyzed on intention-to-treat basis (p = .02), and on protocol analysis of six weekly assessments, including (p = .02) and excluding (p = .05) those on antiparkinsonian medication. Active eradication (blind or open) failed in 4/20, in whom B-lymphocyte count was lower. Their mean time course was: for stride-length, -243 (95% CI -427, -60) vs. 45 (-10, 100) mm/year in the remainder (p = .001); for the ratio, torque to extend to flex relaxed arm, 349 (146, 718) vs. 58 (27, 96)%/ year (p < .001); and for independently rated, visual-analog scale of stance-walk videos (worst-best per individual identical with 0-100 mm), -64 vs. -3 mm from anterior and -50 vs. 11 lateral (p = .004 and .02).

CONCLUSIONS

Interim analysis points to a direct or surrogate (not necessarily unique) role of a particular infection in the pathogenesis of parkinsonism. With eradication failure, bolus release of antigen from killed bacteria could aggravate an effect of ongoing infection.

Downward shift in serum IgM with Helicobacter pylori seropositivity

OBJECTIVE

To determine whether Helicobacter pylori infection is associated with premature immune ageing, with respect to circulating immunoglobulins.

METHODS

Serum immunoglobulin classes and H. pylori anti-urease antibody were measured in 205 subjects (aged 30-89 years), obeying inclusion/exclusion criteria.

RESULTS

IgM decreased (P<0.001) by 0.9 (95% C.I. 0.3, 1.4)% per year, H. pylori seropositivity having an effect equivalent to 25 years of ageing (P<0.02). IgA increased by 0.5 (0.1, 0.8)% per year (P<0.007), IgG being unaffected by age. Seropositivity had no effect on IgA or IgG.

CONCLUSIONS

Increasing age and H. pylori seropositivity are each associated with a downward shift in circulating IgM. If clinical extrapolation is justified, H. pylori eradication may be important in combating susceptibility to infection in old age.

Parkinsonism: differential age-trend in Helicobacter pylori antibody

BACKGROUND

Parkinsonism is associated with prodromal peptic ulceration. Dopamine antagonists provoke experimental ulcer, dopaminergic agents protect, and might inhibit growth of Helicobacter pylori.

OBJECTIVE

To describe the relationship between H. pylori serology and parkinsonism.

METHODS

Serum H. pylori anti-urease-IgG antibody was measured in 105 people with (idiopathic) parkinsonism, 210 without, from same locality. None had received specific eradication therapy.

RESULTS

Controls showed a birth-cohort effect: antibody titre rose from 30 to 90 years (P < 0. 001). Parkinsonism obliterated this (disease status. age interaction, P < 0.05), the differential age trend not being attributable to social class. Those with diagnosed parkinsonism were more likely to be seropositive (odds ratio 2.04 (95% CI: 1.04, 4.22) P < 0.04) before 72.5 years. Overall, titre fell (P=0.01) by 5 (1, 9)% per unit increase in a global, 30-point rating (median 14 (interquartile range 10.5, 17)) of disease severity. No individual category of anti-parkinsonian medication (92% taking) had a differential lowering effect.

CONCLUSIONS

Higher prevalence of seropositivity in parkinsonism, before 8th decade, may be due to host susceptibility/reaction, or, conversely, infection with particular H. pylori strain(s) lowering dopaminergic status. Absence of a birth cohort effect in parkinsonism, despite similar social class representation, may be consequent on eradication, spontaneous (gastric atrophy) or by anti-parkinsonian medication.

Link between Helicobacter pylori infection and idiopathic parkinsonism

The conventional concept for an environmental cause of idiopathic parkinsonism is an insult (e.g. neurotoxin or encephalitis), superimposed on age-related attrition of nigral dopaminergic neurons, and temporally remote from neurological diagnosis. To the contrary, we describe the fit of Helicobacter pylori. This commonest of known bacterial infections, usually acquired in childhood, persists, and has been linked with peptic ulcer/non-ulcer dyspepsia, immunosuppression and autoimmunity. Acquired immunosuppression, predisposing to auto-immunity, is assessed as a model for the pathogenesis of parkinsonism and parkinsonian-like attributes of ageing. Eradication of a trigger has potential to change the approach to parkinsonism, just as it did to peptic ulcer. The tenet of inevitable age-related attrition of dopaminergic neurons may also require revision.

Psychometric properties of the Boston Qualitative Scoring System for the Rey-Osterrieth Complex Figure

Interrater and internal consistency reliabilities were computed for the Boston Qualitative Scoring System, a newly developed system for scoring the Rey-Osterrieth Complex Figure. Subjects (N = 108) included males with right hemisphere stroke (n = 46), left hemisphere stroke (n = 20), dementia (n = 21), and normal controls (n = 21). Interrater reliability coefficients for all scales except asymmetry, which had a reliability coefficient of .2013, ranged from .6342 to .9919, with most in the good to excellent range. Internal consistency reliabilities ranged from .7774 to .9128, also with most in the good to excellent range. Discriminant indices of visuospatial accuracy scales found the scoring system to be useful in distinguishing between individuals based on visuospatial scores.

Association of circulating TNF-alpha and IL-6 with ageing and parkinsonism

INTRODUCTION

We propose that the increase in TNF-alpha and IL-6 in the brain in idiopathic parkinsonism is in response to a peripheral immune/ inflammatory process, so ubiquitous as to be responsible for the resemblance between ageing and parkinsonism.

METHODS

Circulating cytokine was measured in 78 subjects with idiopathic parkinsonism and 140 without, aged 30 to 90 years, all obeying inclusion/exclusion criteria.

RESULTS

Serum TNF-alpha increased (P<0.0001) by 1.37 (95% CI 0.75, 2.00)% x y(-1), IL-6 by 2.63 (1.75, 3.52) (P<0.0005). TNF-alpha appeared elevated in parkinsonians whose postural and psychomotor responses were abnormal, being suppressed where they were normal: trends which contrasted with those in controls (P = 0.015 and 0.05, respectively). Parkinsonism appeared (P = 0.08) to have an effect on IL-6, equivalent to that of >10 years of ageing (28(-3, 69)%), but was not immediately related to between-subject differences in performance.

CONCLUSION

Ageing and pathogenetic insult may be confounded, age being a progression, not a risk, factor.

Parkinsonism: siblings share Helicobacter pylori seropositivity and facets of syndrome

OBJECTIVE

Given a history of peptic ulcer is more frequent in parkinsonism, to investigate the role of Helicobacter pylori in its pathogenesis and of cross-infection in familial aggregation.

METHODS

Facets of parkinsonism were quantified in 33 elderly subjects with idiopathic parkinsonism and in their 39 siblings with double the number of controls, all obeying inclusion/exclusion criteria. Specific-IgG antibody was assayed.

RESULTS

Siblings, compared with controls, had brady/hypokinesia of gait (P< or =0.002), bradykinesia of hands (P = 0.01), abnormal posture (P = 0.001), rigidity (P < 0.001) and seborrhoea/seborrhoeic dermatitis (P = 0.02). Both parkinsonians and siblings differed from controls in the odds of being H. pylori seropositive [odds ratios 3.04 (95% C.I.: 1.22, 7.63) and 2.94 (1.26, 6.86) respectively, P < 0.02], seropositivity being found in 0.70 of sufferers.

CONCLUSION

Familial transmission of chronic infection plus part of syndrome links Helicobacter with causality. Seropositivity not being universal throughout parkinsonism, consequent on gastric atrophy +/- sporadic antibiotic exposure, might explain less aggressive disease in older sufferers.

Cortisol is higher in parkinsonism and associated with gait deficit

INTRODUCTION

We propose an active pathogenic mechanism, involving circulating cortisol, in parkinsonism.

MATERIALS AND METHODS

Serum cortisol was measured in 96 subjects with idiopathic parkinsonism, 170 without, and in 17 spouses and 36 siblings of elderly sufferers with double the number of controls, all obeying inclusion/exclusion criteria.

RESULTS

Cortisol, adjusted for sampling time, was greater (17%, on average, P<0.001) in parkinsonians, but not in relatives. The central cortisol lowering effect of anti-muscarinics was seen (P=0.025). Selegiline may attenuate the disease, and parkinsonism is less frequent in tobacco smokers. Selegiline was associated with a lower cortisol (P=0.03): chronic smoking appeared (P=0.08) to be, irrespective of parkinsonism. Bowel stasis has been implicated in the pathogenesis: cortisol was higher in parkinsonians requiring laxatives (P=0.05). In controls, cortisol was lower, the longer the stride (P=0.02): in parkinsonians, this relationship was numerically reversed. A similar (P=0.01) group performance interaction was seen for deterioration, over 4 years, in gait.

CONCLUSION

Cortisol is doing harm or mirroring something which is. A common pathway for neuronal protection/rescue emerges.

Breadth of base whilst walking: effect of ageing and parkinsonism

BACKGROUND

The effect of healthy ageing and of parkinsonism on breadth of base whilst walking had not been adequately documented.

DESIGN

Height-specific reference ranges for mean foot separation at mid-swing were derived for males and females, age not proving to be a significant influence.

METHOD

Normative data were obtained from 164 healthy volunteers, and foot separation in idiopathic parkinsonism (99 patients) was characterized by comparison.

RESULTS

Parkinsonism was associated with significantly greater within- and between-subject variability in foot separation. There was a linear trend from increased separation in those with bilateral signs but little functional impairment, to decreased separation in the severely impaired but not yet chair or bed bound. Foot separation was best explained by two clinical signs, rigidity and anatomical postural abnormality. A flexed posture was associated with increased separation, rigidity with decreased, the separation manifested being determined by the net effect.

CONCLUSION

In early idiopathic parkinsonism, falling may depend on abnormal posture, and increased breadth of base be compensatory. Later, the decrement in foot separation may become a primary determinant of falls.

Objective measurement of activation of rigidity: diagnostic, pathogenetic and therapeutic implications in parkinsonism

1. Quantification of the effect on rigidity of its 'activation', by isometric grip, of standardized pressure, of the contralateral hand, was explored. Torque required to move the forearm through a fixed angle of 40 degrees, at a controlled rate of 0.5 Hz, in a horizontal plane about a pivotal axis aligned to the elbow joint, was recorded before (12 'baseline' recordings), during (10), and after (> or = 8) activation. Work required per unit displacement was calculated. 2. Specificity: Pilot serial daytime measurements gave an overall mean ratio, work required on activation over baseline, of 2.94 (95% CI 2.53, 3.42) in two elderly untreated parkinsonians, and 3.19 (2.75, 3.71) in two elderly subjects with isolated, clinically activation phenomenon, compared with 1.90 (1.64, 2.21) in two elderly without (P < 0.001), whilst two young adults did not activate, 0.98 (0.85, 1.14). In elderly subjects, work required under activation decreased during the day in health (-10 (-5, -14)% h-1, P = 0.0002), showed no significant change in those with clinical activation (4 (-1, 9)% h-1), and increased in parkinsonians (6 (0, 12)% h-1, P = 0.05): there appeared to be a transitionary state. 3. Validation of methodology: Quantifying the same work ratio on a single occasion in 20 aged parkinsonians (P), their spouses (Ps), 20 index controls (C) without parkinsonism, matched to (P), and their spouses (Cs) gave corroborative evidence of a pre-clinical state, defined by other measurements, in the spouses of sufferers. Values for C, Cs and Ps, 1.89 (1.42, 2.52), 2.38 (1.79, 3.17) and 2.93 (2.20, 3.90) respectively, were in consecutive positions, from health to (P, 2.96 (2.22, 3.95)) disease (P = 0.001 for Ps c.f. C; P = 0.1 for Ps c.f. Cs). Data on change over the day may enhance discrimination. 4. Sensitivity to medicines was illustrated, in two parkinsonians, by randomised, placebo balanced and controlled challenges: 1 and 2 tablets, Sinemet CR (Du Pont Pharmaceuticals, each levodopa 200 mg/carbidopa 50 mg) and 1 tablet, Sinemet-Plus (levodopa 100 mg/carbidopa 25 mg), then two 2 mg tablets, benzhexol. The dopaminergic effect (P < 0.001) was selective for activation (treatment.test-condition interaction, P = 0.004), and showed the expected time profiles. The effect of benzhexol (P = 0.008) lacked such selectivity. Its onset (> 4, < or = 6 h) was delayed, compatible with a gastrointestinal anti-muscarinic action and the subjects' ages. 5. Reliability (Fleiss's criterion) was shown to be good in 30 untreated parkinsonians.

Time course of physical and psychological responses to selegiline monotherapy in newly diagnosed, idiopathic parkinsonism

RATIONALE

Poor specificity of face-value endpoints and the poor sensitivity of gross clinical examination may have militated against demonstrating prophylaxis by selegiline.

METHODS

Objective measures of the four cardinal signs were used as primary outcome criteria in a randomised, double-blind, placebo-controlled, parallel group study of selegiline monotherapy in 25 newly diagnosed elderly sufferers from idiopathic parkinsonism, stratified for sex and Hoehn and Yahr functional staging.

RESULTS

There was a significant interaction between time and nature of treatment with respect to rigidity. The effect of time during active treatment was highly significant: rigidity decreased by 1.3% per week. The worsening of rigidity on placebo was not statistically significant. Neuronal rescue is a possible explanation for the long term, progressive improvement produced by selegiline. No significant treatment effect was seen on the other cardinal signs. However, there was a significant quadratic time trend for arousal on active treatment suggesting tolerance to this effect.

CONCLUSION

The difference in time course between the psychostimulant and physical effects suggests more than one mode of action.

Could seborrhoeic dermatitis be implicated in the pathogenesis of parkinsonism?

The spouses of a group of aged sufferers have been demonstrated to have multifarious differences relevant to parkinsonism from matched controls, which were difficult to explain by selective mating, learned or reactive behaviour. Could parkinsonism be transmissible? The frequency of inflammation and scaling on head or neck was greater (P = 0.05) in these spouses (19 available) than in controls (36), the best discriminating site of inflammation being scalp (P = 0.02). Both seborrhoeic dermatitis and overt, or pre-clinical, parkinsonism occurred in sufferers and spouses: to presume they are not causally related is to accept multiple entities. In favour of seborrhoeic dermatitis being causal for parkinsonism, rather than vice versa, is the involvement of a known organism, Pityrosporum ovale, in the dermatitis, and that the evidence of parkinsonism in the spouses indicated that they were only part way down the path towards the clinical condition.

Hypothesis: the bradyphrenia of parkinsonism is a nosological entity

Reaction time was studied in 103 subjects with idiopathic parkinsonism and 144 without. Central processing time, as measured by the response to a warning, had a component which could be explained by the presence or absence of parkinsonism, but not by the ageing process, a mental test score, or consumption of exogenous substances. Depression did not influence the efficiency of response. Cigarette smoking and anti-parkinsonian medication were associated with greater efficiency.

Defining small differences in efficacy between anti-parkinsonian agents using gait analysis: a comparison of two controlled release formulations of levodopa/decarboxylase inhibitor

1. Stride length is highly relevant to mobility and is sensitive to the effects of levodopa in Parkinsonism. Its selection as the primary outcome criterion allowed comparison of two levodopa/decarboxylase inhibitor formulations using a small number of subjects. 2. It is also desirable to improve stability. An instrumental method, based on infrared telemetry, has been developed which obtains both distance/time measures of gait and broadness of base, as measured by foot separation at mid-swing. The latter was used as a subsidiary outcome criterion. 3. Nine patients (aged 57 to 77 years) then receiving maintenance therapy for idiopathic Parkinsonism with Sinemet CR alone, but who had previously experienced end of dose effect within 4 h of receiving a dose of a conventional formulation of levodopa/decarboxylase inhibitor, were studied. 4. They received, in random order and at least 4 days apart, single doses of one tablet of Sinemet CR (200 mg levodopa/50 mg carbidopa) and of two capsules of Madopar CR (each 100 mg levodopa/25 mg benserazide), with placebo balance, at 10.00 h. Gait analysis was carried out immediately before and half-hourly for 7 h after a challenge. No routine doses of Sinemet CR were taken between 22.00 h on the night before and 17.00 h on the day of a challenge. 5. Analysis of variance showed a highly significant difference in mean stride length (P < 0.001) and in mean foot separation (P = 0.01) between serial time points, irrespective of the nature of treatment. There appeared to be a useful therapeutic response to both challenges.(ABSTRACT TRUNCATED AT 250 WORDS)

Assessment of the bradyphrenia of parkinsonism: a novel use of delayed auditory feedback

Sufferers from parkinsonism have difficulty shifting or developing an appropriate mental set. Delayed auditory feedback may, therefore, disrupt their speech more than that of healthy controls. This was the case when 104 subjects with idiopathic parkinsonism and 144 without were compared. Moreover, the disruptive effect was complementary, in discriminating between those with and without clinical parkinsonism, to the response in reaction time to a warning. Unlike the latter, the disruption caused by delayed auditory feedback appeared independent of mental test score results and uninfluenced by consumption of tobacco or anti-parkinsonian therapy. Neither were influenced by a rating of affect. More precise delineation of the mental disorders of parkinsonism is needed in clinical practice, set against background information on prognosis and drug responsiveness.

Quantification of the cardinal signs of parkinsonism and of associated disability in spouses of sufferers

Work on the causation of idiopathic parkinsonism is limited by relying on gross clinical definition and lack of studies in the old. A prognostic index for parkinsonism, based on hypo/bradykinesia of gait, had considerably higher values in spouses of 20 aged suffers, who had been cohabiting for about half a century, than in 40 controls. Postural abnormality, measured by standing sway and foot separation during walking, was also greater in these spouses. Marked differences remained after correction for relevant covariates. A blinded rigidity rating was greater in the spouses of sufferers, tremor rating was not. The differences found are difficult to explain by selective mating, learned or reactive behaviour. This suggests that environmental causative influences operate in adult life.

Gait in relation to ageing and idiopathic parkinsonism

Distance/time measures of gait in 105 sufferers from idiopathic Parkinsonism, who were able to walk unaided, and 144 healthy controls were examined systematically. Those sufferers with overt fluctuations in control were assessed during their "therapeutic window". Free walking speed was lower for a given cadence in the sufferers, but reached a plateau whilst cadence could still be increased. Age, cognitive function and the range of passive hip flexion were important determinants of gait in them. Even minor degrees of cognitive impairment were associated with reduced free walking speed in sufferers: it appears unwise that they were prescribed more sedatives than the controls. The potential benefit of physiotherapy in maintaining joint flexibility was noted. The deficits in speed of individual sufferers, and hence the estimated potential for prophylaxis and treatment, were unrelated to age at presentation. There was no evidence for a limited period of responsiveness to levodopa therapy in this cross-sectional study.

Objective evidence for tolerance, against a background of improvement, during maintenance therapy with controlled release levodopa/carbidopa

We have investigated whether the potential benefits of a controlled release formulation of levodopa (200 mg)/carbidopa (50 mg), Sinemet CR, are realised during maintenance therapy. Eight sufferers from idiopathic Parkinsonism, mean age 69.9 y, were studied: all exhibited "end of dose" effect within 4 h of a dose of their maintenance therapy with levodopa (100 mg)/carbidopa (25 mg) in a conventional release formulation, Sinemet Plus. They received, in random order, initial single dose challenges with one tablet of Sinemet Plus, one and two tablets of Sinemet CR and placebo alone, each on a separate day. After a mean of 21 weeks on maintenance therapy with Sinemet CR, subsequent single dose challenges with Sinemet CR and placebo were made. Objective measures of performance and blood sampling for assay of plasma concentrations of levodopa and the major peripheral metabolite, 3-0-methyldopa (30MD) were carried out immediately before (10.00 h) and serially until 6 h after each challenge. The overall mean stride length was significantly greater in relation to the subsequent (679 mm) than the initial (517 mm) placebo challenge. Moreover, stride length immediately before the challenges was significantly greater on the subsequent occasions. Improved performance, also seen for free walking speed, was not explained by plasma levodopa or 30MD concentrations. In the initial challenges, the mean increment in stride length achieved by active treatment, as compared with placebo, did not differ significantly between the one (210 mm) and two (235 mm) tablet doses of Sinemet CR: a maximal response had been obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Gait on a shoestring: falls and foot separation in parkinsonism

A novel device for monitoring gait, which can be used in confined spaces, is described. In addition to distance/time assessment of gait, it measures foot separation whilst walking. A field trial illustrates its potential in the investigation of falls.

Reduced axial rotation in the spouses of sufferers from clinical idiopathic parkinsonism

Axial rotation during recumbency was used to quantify the tendency towards parkinsonism with respect to one cardinal sign, brady/hypokinesia. Twenty-four elderly sufferers from idiopathic parkinsonism, their spouses, and 40 control subjects were studied. Significant differences in total angular displacement over 7 h were found between sufferers and their spouses (83% of grand mean) and between spouses of sufferers and controls (31%). These differences could not be accounted for by age or cognitive function. Moreover, the total angular displacement of the spouses was independent of whether they shared a bed with the sufferer. Neither the sufferers and their spouses, nor the 20 couples who constituted the control group, showed any relationship between partners with respect to angular displacement. These findings do not favour learned behaviour, or selective mating as an explanation of reduced movement in spouses of sufferers. Significantly more of the control couples had a single cardinal sign in both partners than expected on the basis of the frequency of a single sign in one partner. Environmental factors operating in adult life could be involved in the pathogenesis of parkinsonism.

Hypothesis: age-associated changes in gait represent, in part, a tendency towards parkinsonism

In 144 healthy, active, asymptomatic volunteers (aged 30-88 years), age explained 33% of the variance in free walking speed. This could not be ascribed simply to differences in physique at maturity, since height had a more important effect on speed (p less than 0.0001) than did leg length (p less than 0.01). Multiple linear regression was used to fit models for speed, by selection from four sets of variables: common physical, body sway, functional anatomy of spine and lower limbs, and psychometric. The best model (which included age) explained little more of the variance (41%) than did age alone. Moreover, incorporation of age into the alternative model, built in its absence, still contributed significantly (p less than 0.0001) to the variance explained. The effect of age on gait appeared to be complex, with an increment in double support time disproportionate to the reduction in speed. We formulate by exclusion, the hypothesis that age-associated changes in gait represent, in part, a tendency towards parkinsonism.

Effect of captopril on functional, physiological and biochemical outcome criteria in aged heart failure patients

1. Captopril was evaluated as an adjuvant to diuretic and digoxin therapy in heart failure in old age, using walking ability, minute ventilation and oxygen consumption and plasma atrial natriuretic factor (ANF) concentration as measures of outcome. 2. Twenty patients, mean (s.d.) age 81 (6) years, entered a double-blind, randomised, crossover study of three treatments, a twice daily regimen of captopril (AA), at a dosage established by titration against serum angiotensin converting enzyme (ACE) activity, the same dosage in the morning with placebo at night (AP), and twice daily placebo (PP). Each treatment lasted 3 weeks. A 2 week run-in period on triple therapy, with AA captopril, was used to assess stability and compliance. Seventeen completed all treatments: three completed two. 3. Any benefit of captopril was modest and there was deterioration in gait on the titrated dosage 3 months afterwards (P = 0.04). Efficacy in the old may be greatest when the titrated dose (25 or 50 mg) is given once daily: the multiple daily doses recommended may be unnecessarily demanding. 4. Walking performance was measured by gait analysis (GA) at free walking speed and by a simple walking test (SWT), in which patients stopped at the first relevant symptom. There was a consistent tendency for four measures of performance (GA: speed, stride length and double support time; SWT distance) to be best on the AP treatment, next best on AA, and worst on PP but for the fifth, SWT speed, AP and AA were similar. The trend appeared most marked for SWT distance, mean (s.e. mean) values for AP, AA and PP being 123 (15), 94 (16) and 75 (16) m, respectively. However, the treatment effect did not reach statistical significance at the 0.05 level. 5. There was no significant difference between treatments in minute ventilation, minute oxygen consumption, or their ratio, either at rest or on exercise. 6. Resting ANF concentrations were nearly four times higher (P = 0.0001) in the patients than those, mean (s.e. mean) 66 (5) pmol l-1, in eleven healthy volunteers of mean age 80 (6) years, and the increase on exercise, seen in the controls (P less than 0.01), was absent. In the patients the resting plasma ANF concentration was significantly affected by treatment (P = 0.03), being less on both AP, 245 (9), and AA, 214 (9) than on PP, 264 (10) pmol l-1 (P = 0.02 and 0.03, respectively). 7. Baseline serum ACE activity was induced on active treatment. The change in ACE activity at 3 h post an active dose was significantly greater on AP than AA (P = 0.005). The increased sensitivity to inhibition during once daily administration was reflected in mean arterial pressure. The pre-dose standing pressure was less on AP than on PP (P less than 0.05), and the change in postural fall (pre-dose minus 2 h post), was greater (P = 0.004), but AA and PP were similar in these respects.(ABSTRACT TRUNCATED AT 400 WORDS)

Objective outcome criteria in trials of anti-parkinsonian therapy in the elderly: sensitivity, specificity and reliability of measures of brady- and hypo-kinesia

1. We compare the sensitivity and specificity of chosen outcome criteria in a placebo-controlled, randomised cross-over study of the efficacy of maintenance therapy with the levodopa/carbidopa combination (Sinemet Plus) alone. Patients were characterised by having idiopathic Parkinsonism with no overt fluctuations in control in relation to individual doses of medication. 2. The effect of omission of a morning dose of maintenance therapy on simple timed tests of mobility and manual dexterity, and on distance/time parameters of gait was studied in fourteen patients (aged 64 to 88 years). Measurements made 2, 4 and 6 h after morning active and placebo treatments were standardised by taking the pre-treatment measurement on that day as baseline. 3. In a linear model, which allowed for the structure of the study, neither the total time taken by each patient to get up from a chair, walk an individually set distance, turn, return to and sit in the chair, nor the rate of progress at fastening the same set of buttons, was sensitive to the treatment effect. 4. Three of the gait parameters, free walking speed, mean stride length and mean double support time, were sensitive to the treatment effect. Correction for the speed of each walk, caused some reduction in the sensitivity of stride length to treatment effect, but that of double support time remained. Speed, and double support time or stride length, appeared to be complementary in defining the treatment effect. 5. The linear modelling revealed the complexity of the treatment effect. Although active treatment, by comparison with placebo, increased free walking speed (P = 0.019), the more levodopa found in the plasma following treatment, (P = 0.0005) and the greater the increment in the concentration of its peripheral metabolite, 3-O-methyldopa (P = 0.006), the less the beneficial effect. This model may reflect reduced uptake into the brain and/or an adverse effect of parent drug or a metabolite. 6. The specificity of free walking speed for the treatment effect was good, as was that of mean stride length, after it had been corrected for speed of each walk, and of mean double support time, after correction for speed and incorporation of the change in lying blood pressure accompanying treatment into the model. 7. The measurements of gait parameters were ranked according to reliability.(ABSTRACT TRUNCATED AT 400 WORDS)